Bárðarbunga_Volcano,_September_4_2014_-_15145866372.jpg

large_Bárðarbunga_Volcano,_September_4_2014_-_15145866372.jpg

medium_Bárðarbunga_Volcano,_September_4_2014_-_15145866372.jpg

small_Bárðarbunga_Volcano,_September_4_2014_-_15145866372.jpg

thumbnail_Bárðarbunga_Volcano,_September_4_2014_-_15145866372.jpg

---
id: '1jIxo_vrUnNTPPAM-2rWlWN_R7hqiM22qgNRfsiBgyr8'
title: '1.Escape Iceland: West Snaefellsjokull and Kirkjufell'
date: '2022-10-09T18:55:07.471Z'
version: 1028
lastAuthor: 'Dianna Gielstra <dianna.gielstra@prescott.edu>'
mimeType: 'text/x-markdown'
links:
  - 'https://translate.google.com/?sl=is&tl=en&text=Sn%C3%A6fellsj%C3%B6kull%0A%0A%0A&op=translate'
  - 'https://translate.google.com/?sl=is&tl=en&text=Sn%C3%A6fellsnes%0A%0A%0A&op=translate'
  - 'https://www.youtube.com/watch?v=Fb9upwbd40A&t=31s'
  - 'https://www.youtube.com/watch?v=rzYAFZPUhZI'
  - 'https://www.youtube.com/shorts/143q3lFTUaU'
  - 'https://commons.wikimedia.org/wiki/File:Snaefellsjokul.JPG'
source: 'https://drive.google.com/open?id=1jIxo_vrUnNTPPAM-2rWlWN_R7hqiM22qgNRfsiBgyr8'
wikigdrive: 'development'
---

Welcome to the West Region!
Welcome to the beginning of your expedition here at Snæfellsjökull stratovolcano and glacier (<em>jökull</em> means glacier in Icelandic)! Your research team's task is to investigate the geodiversity and geoheritage of this site in order to find the clues to escape this location.

**Geodiversity** is defined as the various rocks, minerals, soil, and fossils that are found on the landscape as well as describes the processes that form those patterns. Your team's goal is to learn more about the geodiversity of the Snæfellsnes **Peninsula to be able to look for clues in the virtual landscape to solve the Wordle code to teleport you to the next location.** As the magmatic plume becomes more active, so does the earthquake activity and volcanic activity..Safety is only assured once you ESCAPE Iceland!

# Stop 1: [Snæfellsjökull](https://translate.google.com/?sl=is&tl=en&text=Sn%C3%A6fellsj%C3%B6kull%0A%0A%0A&op=translate)

The [Snæfellsnes](https://translate.google.com/?sl=is&tl=en&text=Sn%C3%A6fellsnes%0A%0A%0A&op=translate) Peninsula is located in the Western region of Iceland, and contains a stratovolcano named Snæfellsjökull with an elevation of 1,446 m.

<img src="/api/images/medium_1000000000000800000005_A80_E9_C59_D2_B85_DF_949_f936dbdb95.jpg" alt="1000000000000800000005A80E9C59D2B85DF949.jpg">

<strong>Fun Fact</strong>: The stratovolcano captured the imagination and interest of Jules Verne who wrote about Snæfellsjökull in his book *Journey to the Centre of the Earth* published in 1864.

Figure: Snæfellsjökull Gla­cier covers the crater of the volcano (Photograph taken by Niccole V. Cerveny).

<img src="/api/images/medium_100000000000080000000600_F6832646731_FE_011_44ddb12acc.jpg" alt="100000000000080000000600F6832646731FE011.jpg">

Typically, Iceland's volcanoes produce basalt with suppressed events that are less destructive as the lava output has greater fluidity. However, stratovolcanoes can be much more explosive like the volcano Eyjafjallajökull that erupted in 2010 and caused international flights to be redirected or grounded. Snæfellsnes is also a stratovolcano and its explosive nature was tempered by the glacier which sits atop it.

Video: [Icelandic volcano fire show](https://www.youtube.com/watch?v=Fb9upwbd40A&t=31s) (ArcticToday, 2022).

The scenario reverses when a volcano erupts under a glacier. Glaciers that are positioned above volcanoes provide water to magma during eruption events…A LOT of water. The presence of water contributes to liquid moving into volcano passages and spaces changing the volcanic system's vapor pressure by increasing it (note - the extreme heat from the volcano causes the water to change phases from liquid to vapor), thus making volcanic events more explosive (Martini et al., 2001). The water and ice dampening of the volcanic chamber creates **hyaloclastic** material, which fills the chambers. As heat from the magma melts glacial ice, it adds more meltwater to the lava creating softer basaltic flows that can accumulate in both height and area below the ice, erupt to the glacier surface, and spread out over the glacier. Once solidified, these physical features are known as **Móberg** or **tuya** features.

Figure: States of volcanic eruption underneath glaciers that form tindars, mounds, and tuyas (Pederson and Grosse, 2014).

<img src="/api/images/medium_10000000000003_F500000307_F95_EA_6_BD_74_EBFA_1_C_9eb07abf99.jpg" alt="10000000000003F500000307F95EA6BD74EBFA1C.jpg">

There is potential for ash to intermix with the water and gasses, creating destructive debris flows known as lahars (Martini et al., 2001). Like <strong>Glacial Outburst Floods</strong>, these types of debris flows move rapidly down the elevation gradient and converge on valley floors in a matter of minutes with great destructive potential. Lahars are a natural hazard that can be damaging to human settlements and infrastructure.

The Snæfellsnes volcano contributed to the geology of this area through eruptions that generated thicker and lighter colored **rhyolitic tephra** layers distributed over the Snæfellsnes Peninsula (Sykora, 2020). Additional material deposits include felsic and mafic igneous rock interspersed with basaltic flows from nearby fissures associated (Kokfelt et al., 2009).

# Stop 2: Mt. Kirkjufell

Congratulations on completing your task at Snæfellsnes volcano! Your research team will now explore another geomorphic feature Mt. Kirkjufell. You might recognize this landform from the popular TV Series <em>Game of Thrones</em>. The unique geomorphology of this feature contributed to the narrative arc of the show as a feature that foreshadowed a premonition, "That is what I saw in the fire, a mountain like an arrowhead." -The Hound. Your new task at this location is to explore the geodiversity of Mt. Kirkjufell.

Mt. Kirkjufell is a notable physical feature in Iceland and is a blend of igneous and sedimentary rock deposited during glacial periods and the warmer, milder periods between glaciation, known as an interglacial (Thordarson and Höskuldsson, 2002; Denk et al., 2011; Sykora, 2020). The pillow lava that is created in **subaqueous** conditions found in subglacial volcanoes is part of the mountain's formation. The glaciers moving around the feature sculpted it into its unique shape.

Figure: Igneous and sedimentary rock deposit layering for Mt. Kirkjufell (Thordarson and Höskuldsson, 2002; Denk et al., 2011; Sykora, 2020).

<img src="/api/images/medium_10000000000003_C3000004_C9_D763926_DFE_0_FC_277_876482b1a9.jpg" alt="10000000000003C3000004C9D763926DFE0FC277.jpg">

<img src="/api/images/medium_100000000000080000000600_AE_32_CA_052_B4475_E3_1b3d881cb5.jpg" alt="100000000000080000000600AE32CA052B4475E3.jpg">

(Photograph taken by Dianna Gielstra)

The Kirkjufell River is another notable physical feature in this area.The origin of the water stream is a source in Helgrindur, which is an eastern mountain ridge. The water moves through the canyon areas contributing to erosion and formation of Proskuldar, or cliffs, as well as the Kirkjufellsfoss, the waterfalls of Kirkjufell.

**Video:** **[Kirkjufellfoss](https://www.youtube.com/watch?v=rzYAFZPUhZI)**

**Video:** **[Kirkjufellfoss in close proximity](https://www.youtube.com/shorts/143q3lFTUaU)**

[Enter VR](/scenes/mt-kirkjufell)

**Hint:** A component of softer basaltic flows that create móberg ortuya features.

<iframe id="player" type="text/html" width="640" height="500"
  src="https://geoepic.app/wordle/play?sol=water&lnk=/lessons/field-trip-escape-iceland/11"
  frameborder="0"></iframe>
  
# GLOSSARY

**Glacier** A body of ice that forms over a long period of time through the compaction and recrystallization (refreezing) of snow over time. The density of the glacial ice allows the glacier to exist throughout the year (even at temperatures above freezing).
**Glacier Outburst Flood** (Jokulhaup in Icelandic) occurs when the glacial lagoon formed at the terminus of the glacier breaches the glacial till deposits and empties the body of water in a flood through the glacial outwash plain.

**Interglacial** A period of time that exists between ice ages; the average length of an interglacial period is 10,000 years

<strong>Móberg</strong>: A mountain of volcanic material that has steep sides and a flattened top formed from a central vent of a volcano that erupted under a thick ice sheet or glacier. The lava can also break through and spread out over the ice.

**Peninsula** An extension of landmass that is surrounded by water on three sides

**Rhyolitic** A silica rich extrusive volcanic rock type that is thick and pasty in consistency

**Subaqueous** Formation or process positioned underwater.

**Tephra** Dust and ash ejecta from a volcano

**Tuya** A volcanic mound that has steep sides and a flattened top because of lava eruptions beneath a thick ice sheet or glacier.

**Stratovolcano** An explosive type of volcano that is large/mountainous in size as it is built from successive layers of violent eruptions over a long period of time

# REFERENCES

ArcticToday. (2022). People gather to watch Icelandic volcano fire show - Reuters. https://www.youtube.com/watch?v=Fb9upwbd40A&t=31s

Oosting, H. (2005). Snæfellsjökulll. [https://commons.wikimedia.org/wiki/File:Snaefellsjokul.JPG](https://commons.wikimedia.org/wiki/File:Snaefellsjokul.JPG)

Pedersen, G.B.M., Grosse, P. (2014), <em>Morphometry of subaerial shield volcanoes and glaciovolcanoes from Reykjanes Peninsula, Iceland: Effects of eruption environment. Journal of Volcanology and Geothermal Research 282</em>, (2014), 115-133.

Sykora, S. (n.d.). Exploring the earth. Retrieved September 28, 2022. http://exploringtheearth.com/2016/07/05/geological-journey-iceland-land-fire-ice-part-1/

Study Area 1: West Region!

---
id: '1hTUz1mAUxGQGBvIgVEuJZerMUFiqdNxfk_QZF2s_BwE'
title: '2.Escape Iceland-Southwest Region-Bridge'
date: '2022-10-09T18:57:00.787Z'
version: 1155
lastAuthor: 'Dianna Gielstra <dianna.gielstra@prescott.edu>'
mimeType: 'text/x-markdown'
links:
  - 'https://500px.com/pixael'
  - 'https://commons.wikimedia.org/wiki/Category:CC-BY-3.0'
  - 'https://en.wikipedia.org/wiki/Fagradalsfjall'
  - 'https://www.youtube.com/watch?v=Fb9upwbd40A&t=31s'
  - 'https://en.wikipedia.org/wiki/J%C3%B6kull_(journal)'
  - 'https://web.archive.org/web/20210320233317/https://www.usnews.com/news/news/articles/2021-03-19/long-dormant-volcano-comes-to-life-in-southwestern-iceland'
  - 'https://opengeology.org/textbook/2-plate-tectonics/#241_Continental_Rifting'
  - 'https://adsabs.harvard.edu/full/1981LPICo.457...56W'
source: 'https://drive.google.com/open?id=1hTUz1mAUxGQGBvIgVEuJZerMUFiqdNxfk_QZF2s_BwE'
wikigdrive: 'development'
---

Welcome to the Southwest Region!
Stay motivated and continue your expedition here at Bridge Between Continents (<em>also known as Leif's Lucky Bridge</em>)! Your research team's task is to investigate the geodiversity and geoheritage of this site in order to find the clues to escape this location. You are learning so much about Iceland's <strong>geodiversity</strong>!

Geodiversity is defined as the various rocks, minerals, soil, and fossils that are found on the landscape as well as describes the processes that form those patterns. Your team's goal is to learn more about the geodiversity of the **continental rift** and <strong>rift zone</strong>. Remember, to be able to look for clues in the virtual landscape to solve the Wordle code to teleport you to the next location. As the magmatic plume becomes more active, so does the earthquake activity and volcanic activity..Safety is only assured once you ESCAPE Iceland!

# Stop 3: Bridge Between Continents

The Bridge Between the Continents is found on the Reykjanes Peninsula and it serves as a representation of the continental rift.

<img src="/api/images/medium_1000000000000800000005_A8_DE_056_CF_4_B7255457_0551333886.jpg" alt="1000000000000800000005A8DE056CF4B7255457.jpg">

Leif's Lucky Bridge is situated as a connection across a small **fissure** along the **rift zone** between the North American Plate to the west and the Euroasian Plate to the east (Photography by Giuseppe Milo). The submarine Reykjanes Ridge extends onto the terrestrial landscape with the mid-Atlantic Ridge visible in the southwestern portion of Iceland.

<img src="/api/images/medium_10000000000007_D000000465_A5_B4_E002_EFCDADED_77215b14b5.jpg" alt="10000000000007D000000465A5B4E002EFCDADED.jpg">

**Photo** of the Bridge Between Continents, Iceland adapted from Giuseppe Milo (2017) [CC-BY-3.0](https://commons.wikimedia.org/wiki/Category:CC-BY-3.0), Self-published work.
The volcanic systems in this area have been classified into five geographic areas, and they are as follows: Hengill, Brennisteinfjöll, Krísuvík, Svartshengi and Reykjanes. The geochemistry for Svartshengi and Reykjanes are similar, so they are sometimes grouped into one category referred to as the Reykjanes Volcanic System (Einarsson, 2008; Einarsson and Saemundsson, 1987; Sigmundsson, 2006).The area is littered with spatter cones (aka cinder cones) and lava fields with perceptible structures of one of the world's major plate boundaries where the North American Plate meets the Eurasian Plate (Photograph taken by Dianna Gielstra).

<img src="/api/images/medium_1000000000000800000006000_E12_C63114_D0_D5_D0_9f0bb716a1.jpg" alt="1000000000000800000006000E12C63114D0D5D0.jpg">

**The volcanic systems and zones found in Iceland.**

<img src="/api/images/medium_100000000000054500000468_BDBFA_9_B67_F0712_C0_6a33c219d6.jpg" alt="100000000000054500000468BDBFA9B67F0712C0.jpg">

The circle in the figure above shows the position of Iceland's mantle plume foci (Wolfe et al., 1997). The displayed dotted line defines the limits and boundary of the East Volcanic Zone (Thordarson and Hoskuldsson, 2008).

**Table: Abbreviations for volcanic systems and zones displayed in the previous figure** \*\*(<strong>Thordarson and Hoskuldsson, 2008).</strong><table><tr><td><strong>Abbreviation</strong></td><td><strong>Name of the System or Zone</strong></td></tr>| ------------ | -------------------------- |
<tr><td>RR</td><td>Reykjanes Ridge</td></tr><tr><td>RVB</td><td>Reykjanes Volcanic Belt</td></tr><tr><td>SISZ</td><td>South Iceland Seismic Zone</td></tr><tr><td>WVZ</td><td>West Volcanic Zone</td></tr><tr><td>MIB</td><td>Mid-Iceland Belt</td></tr><tr><td>EVZ</td><td>East Volcanic Zone</td></tr><tr><td>NVZ</td><td>North Volcanic Zone</td></tr><tr><td>TFZ</td><td>Tjörnes Fracture Zone</td></tr><tr><td>KR</td><td>Kolbeinsey Ridge</td></tr><tr><td>OVB</td><td>Öræfi Volcanic Belt</td></tr><tr><td>SVB</td><td>Snæfellsnes Volcanic Belt</td></tr></table>


Table: Attributes of the figure, Numbers refer to volcanic systems (Thordarson and Hoskuldsson, 2008<strong>).</strong>

<img src="/api/images/medium_10000000000005_C0000004396_AA_02713_F1_F5_C2_C5_79fbb46cbd.jpg" alt="10000000000005C0000004396AA02713F1F5C2C5.jpg">

This area has young geology, and the youngest lava field dated to 1240. The area was covered in glaciers from the Weichselian glacial period that occurred 15,000 to 12,000-years before present. Volcanic activity increased after deglaciation resulting in the Holocene shield volcanoes, which are predominant in this area along with cinder cone volcanoes.
There are also many small craters, called Stampar, and spatter cones found here. After 815 years of inactivity, the Fagradalsfjal[l](https://en.wikipedia.org/wiki/Fagradalsfjall) volcano began erupting again on" or "erupted on March 19, 2021 and remains active.

Video: [Icelandic volcano fire show](https://www.youtube.com/watch?v=Fb9upwbd40A&t=31s) (ArcticToday, 2022).

The Mid Atlantic Ridge is broken up into segments along its length, and rifting occurs at some of these segments. <strong>Rift fissures</strong>, linear fracture<strong>s</strong> in the earth's crust, are the most visible physical feature in this area's geology. The continental rift itself is several kilometers wide, but site visitors can explore\*\*\*\* the continental rifting process where superheated mantle material is lifted up because of the underlying **convective currents** (Salt Lake Community College, n.d.).

<img src="/api/images/medium_1000000000000800000006004_A8_A1_E1_B96479_E0_D_278dac39fb.jpg" alt="1000000000000800000006004A8A1E1B96479E0D.jpg">

These currents create tension in the **lithosphere** that causes **divergent plate boundaries** to separate making the continental lithosphere break-up along the fault lines.

**Fun Fact!** Approximately 75% of the human population lives on the Eurasian Plate (Reykjanes Geopark, Iceland signage at Bridge Between Continents)!

According to the continental drift theory the Eurasian and North American **tectonic plates** are continuously drifting apart because of these great forces under the rifts. As the plates diverge, continued stress is created by the tension that builds up as the plates move away from each other. The mantle plume, commonly referred to as a hotspot, is stationary; however, the sea-floor spreading hypothesis explores how in this area the ocean moves away from the mid-oceanic ridge trending west at a rate of 0.3 cm/year (Einarsson, 2008). The movement is somewhat unique to Iceland in that there is a **continental rift jump.** A continental rift jump occurs when a moving sea-floor spread arcs and migrates back to a hotspot (Wood, 1981). In Iceland, the rift extends from North to South and therein lies a bulk of the activity, but as there is an eastward migration of the mantle plume, quieter rift zones could have some volcanic activity (Wood, 1981).

Reykjanes Peninsula's Bridge Between the Continents is approximately 7 meters high. Bottom of the fissure is filled with soft sediments deposited by aeolian (wind-blown) processes based on the prevailing wind patterns. The sediments blowing across the fissure fall out over and are trapped within the tectonic feature. Coarser than loess,which is larger than sand grain sizes, these sediments show that high wind speeds are blowing in directional pathways across the canyon (Photograph showing the coarse, light sediments taken by Dianna Gielstra).

<img src="/api/images/medium_10000000000006000000080019_A5_FCAE_351_CE_7_FF_a522e6bbbe.jpg" alt="10000000000006000000080019A5FCAE351CE7FF.jpg">

The fissure is an area that is open and flatter than the surrounding landscape. The Bridge Between Continents is a representation of the mid-Atlantic Ridge, which extends up to 5 km wide. This area is just a small fissure, a crack in the side of the larger rift.

Other features in the area include tindars and rounded, smooth to rough basalt. Some areas show the potential for polygonal shapes, but are not hexagonal at this location. The hexagon shape is the most efficient shape in nature and is often found in lava formations throughout Iceland. As lava cools and hardens more uniformly from the inside, the hardening of the outer layer causes contraction fractures in the rock that can form Polygonal shapes (triangular, hexagons, pentagons, and heptagons). There are also a few areas at this site that show mass movement down slope, like a rotational slump.

A nearby feature is found near Lake Kleifarvatn. Landforms that are Mobergs or tuyas are mounds created by subglacial eruptions. The mixing of lava and water creates gravelly material (unconsolidated) with chunks of basalt referred to as a matrix of "hydrated hyaloclastite lava". The layers cool in between eruptions lithify. This creates what looks like sequences of the eruption (Photograph taken by Dianna Gielstra).

<img src="/api/images/medium_100000000000080000000600_AB_4_D4_FA_39950_A4_FC_084ab81127.jpg" alt="100000000000080000000600AB4D4FA39950A4FC.jpg">

These different levels of solidification have different hardness. As seen in the above image, the erosion patterns highlight more resistant layers that maintain their form versus the softer layers that show material eroding and moving downslope. This landform is adjacent to the large lowland area that forms Lake Kleifarvatn and may experience greater erosion from overland flow and runoff.

**[Enter VR](/scenes/bridge-between-continents-iceland)**

**Hint:** The rift zone is positioned between this feature type.

<iframe id="player" type="text/html" width="640" height="500"
  src="https://geoepic.app/wordle/play?sol=plate&lnk=/lessons/field-trip-escape-iceland/12"
  frameborder="0"></iframe>
  
# GLOSSARY

<strong>Cinder Cones/Spatter Cone</strong>: Small volcanoes (less than 450 meters) that form by the ejection of cinders that then fall around the earth fracture in a conical shape

**Continental Drift Theory** Originally proposed by Alfred Wegener in 1915 to describe the movement of the continents; later proven and renamed Plate Tectonic Theory
**Continental Rift**

**Continental Rift Jump:** Since the whole divergent boundary does not move at a similar rate, the boundary will develop transform faults (slide side by side) so that the part that is opening can move independently of the entire boundary. This causes "jumps" within the rift. On a tectonic map, these appear like stitches in a nonlinear cut.

**Convective Currents** Between the core and crust of the earth with relatively hotter and colder areas that create circulation cells within the molten asthenosphere/mantle of the earth

**Divergent Plate Boundaries** Location in which the tectonic plates are pulling apart from one another

**Fault:** Cracks or fissures within the earth's crust

**Lithosphere** The solid surface of the earth, above the mantle

**Mantle Plumes/Hot Spots** Fixed areas within the earth's mantle in which hotter magma rises to the surface and thins the lithosphere to the point of volcanic activity.

**Móberg** Palogonite tuff, basalt that has undergone transformation because of contact with water. The exposure can create lighter colored, thinner material.

**Rift Zone** Area of the earth's crust where divergent motion is taking place and the tectonic plates are pulling apart

**Rift Fissures** cracks along the rift zone

**Rotational Slump** A form of mass wasting or movement in which gravity helps to pull down or "slump" earth materials at the surface in a rotation supported by underlying bedrock

**Tectonic Plates** Individual lithospheric plates the move through divergence, convergence, or transform motion

**Tindars** A small mound of volcanic material that collects in the void space beneath the ice as the volcanic activity melts the underside of the glacier.

# REFERENCES

Andrews, R. (2015). Why is the Giant's Causeway hexagonal. https://www.iflscience.com/why-columnar-basalt-almost-always-hexagonal-31278

Bindeman, I. N.; Deegan, F. M.; Troll, V. R.; Thordarson, T.; Höskuldsson, Á; Moreland, W. M.; Zorn, E. U.; Shevchenko, A. V.; Walter, T. R. (29 June 2022). "Diverse mantle components with invariant oxygen isotopes in the 2021 Fagradalsfjall eruption, Iceland". <em>Nature Communications</em>. **13** (1): 3737. doi:10.1038/s41467-022-31348-7.

Einarsson, P. (2008). "Plate boundaries, rifts and transforms in Iceland". <em>[Jökull](https://en.wikipedia.org/wiki/J%C3%B6kull_(journal))</em>. **58** (12): 35–58.

"Long dormant volcano comes to life in southwestern Iceland". <em>US News</em>. Associated Press. 19 March 2021. [Archived](https://web.archive.org/web/20210320233317/https://www.usnews.com/news/news/articles/2021-03-19/long-dormant-volcano-comes-to-life-in-southwestern-iceland) from the original on 20 March 2021. Retrieved 20 March 2021.

Pedersen, G.B.M., Grosse, P. (2014), <em>Morphometry of subaerial shield volcanoes and glaciovolcanoes from Reykjanes Peninsula, Iceland: Effects of eruption environment. Journal of Volcanology and Geothermal Research 282</em>, (2014), 115-133.

Salt Lake Community College. (n.d.). An Introduction to Geology: 2.4.1. Continental Rifting. [https://opengeology.org/textbook/2-plate-tectonics/#241_Continental_Rifting](https://opengeology.org/textbook/2-plate-tectonics/#241_Continental_Rifting)

Thordarson, T, & Larsen, G. (2007). Volcanism in Iceland in historical time: Volcano types, eruption styles and eruption histories. Journal of Geodynamics, 43: 118-152. https://pages.mtu.edu/\~raman/papers2/Thordarson%20and%20Larsen%202007%20-%20Volcanism%20in%20Iceland.pdf

Wood, (1981). Continental rift jumps?Abstracts of Papers presented to the conference on Processes of Planetary Rifting. A Lunar and Planetary Institute Topical Conference held December 3-5, 1981, in Napa Valley, CA. Co-sponsored by LPI, the American Geophysical Union, the National Science Foundation, and NASA. LPI Contribution 457, published by the Lunar and Planetary Institute, 3303 Nasa Road 1, Houston, TX 77058, 1981, p.56. [https://adsabs.harvard.edu/full/1981LPICo.457...56W](https://adsabs.harvard.edu/full/1981LPICo.457...56W)

Study Area 2: Southwest Region!

---
id: '1tfZ1Vw1vt5axr7akzFm-IYsGy7Tavg7sWUh8ytpENBA'
title: '3.Escape Iceland-Geysir'
date: '2022-10-09T18:58:19.160Z'
version: 322
lastAuthor: 'Dianna Gielstra <dianna.gielstra@prescott.edu>'
mimeType: 'text/x-markdown'
links:
  - 'https://commons.wikimedia.org/wiki/Category:CC-BY-3.0'
  - 'https://www.youtube.com/watch?v=3NSMHxv_dmU'
  - 'https://volcanicbenefitstomankind.weebly.com/geyser-processes.html'
  - 'https://www.youtube.com/watch?v=Jt7qF-2kgdw'
  - 'https://commons.wikimedia.org/wiki/File:Geysir-iceland-1.jpg'
  - 'https://commons.wikimedia.org/wiki/Geysir_Geothermal_Field#/media/File:2005-05-31_Geysir_01.jpg'
  - 'https://volcano.si.edu/volcano.cfm?vn=371803'
source: 'https://drive.google.com/open?id=1tfZ1Vw1vt5axr7akzFm-IYsGy7Tavg7sWUh8ytpENBA'
wikigdrive: 'development'
---
Welcome to the South Central Region!
Congratulations! Your research team is making its way across Iceland! You have now reached the central portion of the island country. Here you will explore the geodiversity found within geothermal areas. Your research team's task is to investigate the geodiversity and geoheritage of this site in order to find the clues to escape this location. Keep learning about Iceland's **geodiversity**!
Geodiversity is defined as the various rocks, minerals, soil, and fossils that are found on the landscape as well as describes the processes that form those patterns. Your team's goal is to learn more about the geodiversity of the** geothermal system. Remember, to be able to look for clues in the virtual landscape to solve the Wordle code to teleport you to the next location.** As the magmatic plume becomes more active, so does the earthquake activity and volcanic activity..Safety is only assured once you ESCAPE ICELAND!


# Stop 3: Geysir

Geysir geothermal area is located at 700 meters of elevation at the site of what used to be a basaltic volcano with rhyolitic lava domes (Smithsonian Institution, n.d). Geology in this area formed during the ice age (**Pleistocene** <0.8 m.y.) and includes **hyaloclastite**, **pillow lava**, **breccia** and associated sediments.


<img alt='1000000000000800000005A86D459A07C3CA1EC8.jpg' src='/api/images/medium_1000000000000800000005_A86_D459_A07_C3_CA_1_EC_8_f336bd0748.jpg' height=600 width=800/>

There has not been a volcanic eruption here since the Pleistocene, but Geysir is found within **Móberg** formations, or landforms that formed when **lava** is extruded beneath a glacier during the Pleistocene (less than 0.8 .y.).  When bedrock formed beneath the glacial ice, the geology became structurally weaker, softer, and more susceptible to the effects of erosion. 

<img alt='1000000000000800000000C9D32C308210A8A5DB.jpg' src='/api/images/medium_1000000000000800000000_C9_D32_C308210_A8_A5_DB_ff56863397.jpg' height=600 width=800/>

Panorama of the Geysir geothermal area. Photo by Hansueli Krapf (2005).[CC-BY-3.0](https://commons.wikimedia.org/wiki/Category:CC-BY-3.0), Self-published work.


The Geysir area contains extinct underlying volcanic chambers from the Haukadalur Valley geothermal activity and from volcanic vents that provide residual heat from the Laugarfjall system.  The geothermal system is contained by **basalt** bedrock with water temperatures heated upwards of 200-250°C. The heat is transferred through deeper groundwater flows at 1-2 km depth moving through northeastern trending** fractures**. The geothermal activity produces **geysers**, **fumaroles**, and **mudpots**.

<img alt='1000000000000780000005A0CD221588E2EF7502.jpg' src='/api/images/medium_1000000000000780000005_A0_CD_221588_E2_EF_7502_d47fe896a8.jpg' height=600 width=800/>

Looking down from the Laugarfjall lava dome. Photo by Hansueli Krapf (2005) [CC-BY-3.0](https://commons.wikimedia.org/wiki/Category:CC-BY-3.0), Self-published work.


**Fun Fact!** The term geyser originates from the geysers in the Geysir geothermal area. These are the first geysers described in books!


Video:[ Fumarole at Geysir geothermal area](https://www.youtube.com/watch?v=3NSMHxv_dmU)


Great Geysir, once the only known geyser in the west, is one of the largest geothermal features in the world. Though the visitor area is limited to 0.2 km2 , the area of the **geothermal vent** is approximately 3 km2. This physical feature was the original geyser for which all other geothermal water **spouts** are named. Today, Geysir is classified as dormant with little activity since the early 1900s. Mentioned in historical documents since 1294, Geysir's activity typically follows earthquake activity.


Figure: Geothermal pools found in the Geysir area (Photograph taken by Niccole V. Cerveny).

<img alt='100000000000080000000600BA0A531834378B97.jpg' src='/api/images/medium_100000000000080000000600_BA_0_A531834378_B97_645b393bef.jpg' height=600 width=800/>

There are several phases to creating a geothermal eruption. The subsurface ground structures include a maze of conduits that support groundwater flow convergence to a single vent that leads to the surface. Water found in the upper area of drainage consists of runoff from precipitation and ranges in temperature just below the boiling at 85-95°C.  Deeper in the conduit network and closer to geothermal heat, temperatures can exceed 120°C, but the pressure from the water above keeps these deeper waters from boiling. Activity that mixes the upper and lower water sources, such as shaking resulting from an earthquake, allows the upper water to reach the boiling point while relieving the pressure on the water stores below. The redistribution of pressure and water achieving boiling points causes steam formation in the system and forces the overlying water to explode through the vent. Several hours between geyser eruptions are needed to recharge the system as groundwater refills the conduits. 

![](/api/images/100000000000017_E0000014_E1_E357_F436_A5_DEC_08_48e9e56048.jpg)

Shapes of geyser conduits that can influence geyser behavior ([https://volcanicbenefitstomankind.weebly.com/geyser-processes.html](https://volcanicbenefitstomankind.weebly.com/geyser-processes.html))
The Geysir geyser is impacted by tourism, and conservation efforts are used to protect this feature. Past tourist activity included depositing pebbles, trash, and turf into the geyser's central vent to encourage an eruption. Unfortunately, these artifacts within the central vent formed a substrate for silica deposits, or **sinter**. The sinter halted eruptive activities. Iceland officials drilled the sinter bowl to encourage more eruptions. Efforts increased with additions of soap to the sinter bowl on special occasions to reduce the water's surface tension and encourage eruptive behavior from the geyser. 


Figure: The inactive Geysir impacted by tourism shows signs of plant growth and succession  (Photography taken by Niccole V. Cerveny).

<img alt='10000000000006000000080012BA0C49B7731C91.jpg' src='/api/images/medium_10000000000006000000080012_BA_0_C49_B7731_C91_a4e22c29dc.jpg' height=600 width=800/>

Figure: Strokkur Geyser is still active in this area (Photograph and video taken by Niccole V. Cerveny).

<img alt='100000000000080000000600F6DCD101A22F7EF2.jpg' src='/api/images/medium_100000000000080000000600_F6_DCD_101_A22_F7_EF_2_1eabac54b2.jpg' height=600 width=800/>

[Video of Strokkur Geyser erupting](https://www.youtube.com/watch?v=Jt7qF-2kgdw).
Now tourists are provided footpaths clear of rocks and debris. The paths reduce trampling to these geothermal areas.  Signs are distributed throughout the area to educate tourists and locals of the sensitive nature of the environment and these features.
Conservation efforts to protect the Geysir geothermal area and Hvítá River watershed include more management of tourist movement and activity. Trails are provided for intentional movement to navigate to features to reduce trampling and erosion, and overall damage to natural features. These paths secure safety for visitors, as do barriers in the form of chain fencing to maintain safe distances within the geothermal site while communicating the variability of temperatures within the site. Signage improves awareness and discourages visitors from throwing debris into the vents to reduce harm to natural features. Maintaining natural water flow has helped to protect thousands of acres of land containing farms and native vegetation which needs natural volumes and rhythms of water flow.  Estimates are that 50% of the vascular plants native to Iceland are found in this area (Icelandic Institute of Natural History, n.d.). 
Figures: Barriers and signage to keep both tourists and physical features of the Geysir are safe (Photographs taken by Dianna Gielstra and Niccole V. Cerveny).

<img alt='10000000000008000000060024DE4B61865316CE.jpg' src='/api/images/medium_10000000000008000000060024_DE_4_B61865316_CE_6c3acaf6e4.jpg' height=600 width=800/>
<img alt='10000000000008000000060032C4148A436FF262.jpg' src='/api/images/medium_10000000000008000000060032_C4148_A436_FF_262_d5745b3a3d.jpg' height=600 width=800/>


<img alt='100000000000060000000800D34C8D784573AE6E.jpg' src='/api/images/medium_100000000000060000000800_D34_C8_D784573_AE_6_E_1357250dd1.jpg' height=600 width=800/>
<img alt='100000000000060000000800CA0FB4105FD6F66C.jpg' src='/api/images/medium_100000000000060000000800_CA_0_FB_4105_FD_6_F66_C_6bae82b4a9.jpg' height=600 width=800/>

Haukadalur Field also includes additional geysers (Strokkur, Blesi, Konungshver, Fata, Ópperishola, Smíd(th)ur), fumaroles, hot springs, mud pots. Although Geysir is no longer regularly active, Strokkur is dependable and erupts every 5-10 minutes. The high temperature location continues to support the mobilization of amorphous silica that creates sinter deposits and artificial drilling of the sinter bowls is still a regular practice. 


[Enter VR](/scenes/geysir)


**HINT:**  A product of the geyser.

<iframe id="player" type="text/html" width="640" height="500"
  src="https://geoepic.app/wordle/play?sol=steam&lnk=/lessons/field-trip-escape-iceland/13"
  frameborder="0"></iframe>


# GLOSSARY

**Basalt** An igneous rock with fine grains and contains plagioclase feldspar, olivine, and pyroxine minerals.

**Breccia** Rock composed of coarse, angular pieces. It can be formed through sedimentary rock processes, or created with grinding forces around faults.

**Fracture** A rock that has a crack, tear, or fault because of stress forces.
 
**Fumarole** A vent in areas with volcanic activity in which gasses escape.

**Geothermal System** A geological setting where earth's internal heat flows to the surface and creates hot water and steam.

**Geothermal** **Vent** A crack or hole in the earth through which hot water and gasses can escape.
**Geysers** A natural water source that is heated by geothermal energy resulting in release as a fountain of water and steam into the air. This release may occur with regular intervals.
**Hyaloclastite** Tuff-like deposit. Material created as basalt flowed under water from the melted glacier.

**Lava** Molten rock that escapes is transported to earth's surfaces when it is extruded through vents and fissures.

**Móberg** Palogonite tuff, basalt that has undergone transformation because of contact with water. The exposure can create lighter colored, thinner material.

**Mudpot** hotspring that contains mud and is found in geothermal areas. Sulphurous and rich in minerals that can create multiple colors. Sometimes these are referred to as "painted pots".

**Pillow Lava** Lava formed under water, cools into ellipsoidal shape near the vent. Looks more rounded and smooth.

**Pleistocene** geologic epoch of the Quaternary period of the Cenozoic representing approximately 0.8 million years before present. 

**Sinter** Precipitate from mineral springs that create hard deposits of silica.

**Spouts** Liquid under force and pressure that spews from a vent.

# REFERENCE

Joaoleitao. (2008). The Great Geysir in the Haukadalur Valley, Iceland. [https://commons.wikimedia.org/wiki/File:Geysir-iceland-1.jpg](https://commons.wikimedia.org/wiki/File:Geysir-iceland-1.jpg)
Hansueli Krapf (2005). Laugarfjall lava dome. Views of the whole geothermal field.  CC BY-SA 3.0
[https://commons.wikimedia.org/wiki/Geysir_Geothermal_Field#/media/File:2005-05-31_Geysir_01.jpg](https://commons.wikimedia.org/wiki/Geysir_Geothermal_Field#/media/File:2005-05-31_Geysir_01.jpg)
 Krapf, H. (2005) Laugarfjall lava dome. Panorama of the Geysir geothermal area. Views of the whole geothermal field.  CC BY-SA 3.0 https://commons.wikimedia.org/wiki/Geysir_Geothermal_Field#/media/File:2005-05-31_Geysir_01.jpg
Hansueli Krapf (2005) Geysir geothermal area[CC-BY-3.0](https://commons.wikimedia.org/wiki/Category:CC-BY-3.0), Self-published work.https://commons.wikimedia.org/wiki/Geysir_Geothermal_Field#/media/File:2005-05-31_Geysir_01.jpg
Smithsonian Institution National Museum of Natural History. (n.d.). Geysir. [https://volcano.si.edu/volcano.cfm?vn=371803](https://volcano.si.edu/volcano.cfm?vn=371803)
Volcanic activity and its benefits to mankind. (n.d.). Shape of geyser conduits that can influence geyser behavior.  Retrieved on October 2, 2022.. ([https://volcanicbenefitstomankind.weebly.com/geyser-processes.html](https://volcanicbenefitstomankind.weebly.com/geyser-processes.html))




Study Area 3: South Central Region!

---
id: '1OfVa-v4IUAC6pmtmMUMSJP23rPmCVhjJeU2-Zt_XTdM'
title: '4.Escape Iceland-Solheimajokull'
date: '2022-10-09T18:59:32.040Z'
version: 384
lastAuthor: 'Dianna Gielstra <dianna.gielstra@prescott.edu>'
mimeType: 'text/x-markdown'
links:
  - 'https://translate.google.com/?sl=is&tl=en&text=M%C3%BDrdalsj%C3%B6kull%0A%0A%0A&op=translate'
  - 'https://notendur.hi.is/mtg/pdf/2021_Jokull71_MTGetal_Katla1918_II.pdf'
source: 'https://drive.google.com/open?id=1OfVa-v4IUAC6pmtmMUMSJP23rPmCVhjJeU2-Zt_XTdM'
wikigdrive: 'development'
---
Welcome to the South Region and Sólheimajökull!
Your research team has reached the third of five stops to escape the lava flows of Iceland. This journey has gotten you closer to the coast where emergency personnel await your team with rescue ships. At this site you must explore the geodiversity and geomorphological diversity found within outlet glacier geological settings to find the clues to escape this location. Please reflect on all that you are learning about Iceland's **geodiversity**!
Geodiversity is defined as the various rocks, minerals, soil, and fossils that are found on the landscape as well as describes the processes that form those patterns. Your team's goal is to learn more about the geodiversity of these glacier-influenced systems**. Remember, to be able to look for clues in the virtual landscape to solve the Wordle code to teleport you to the next location.** As the magmatic plume becomes more active, so does the earthquake activity and volcanic activity..Safety is only assured once you ESCAPE ICELAND!

# Stop 4: Solheimajökull

Sólheimajökull is a receding tongue of an outlet glacier located on the South Coast of Iceland. The outlet glacier originates from the much larger [Mýrdalsjökull](https://translate.google.com/?sl=is&tl=en&text=M%C3%BDrdalsj%C3%B6kull%0A%0A%0A&op=translate) Icecap that is 590 kilometers2, which covers the volcano Katla (Gudmundsson et al., 2021).The feature is 2 kilometers wide and has a length of 8 kilometers (Guide to Iceland, n.d.). 

<img alt='1000000000000800000005A8E06C849CBA318E07.jpg' src='/api/images/medium_1000000000000800000005_A8_E06_C849_CBA_318_E07_21d2c7acbd.jpg' height=600 width=800/>

Oblique aerial photograph of Sólheimajökull, Iceland.  Photo *taken by* Oddur Sigurðsson (1985), Icelandic Meteorological Office. *Adapted from the USGS (n.d.).*

<img alt='100000000000080000000552FF2485B912E30A72.jpg' src='/api/images/medium_100000000000080000000552_FF_2485_B912_E30_A72_b6be746966.jpg' height=600 width=800/>


View of the outlet glacier from the ground (Photograph by Dianna Gielstra).

<img alt='10000000000003EB00000539FBFDE5C07EFB59F5.jpg' src='/api/images/medium_10000000000003_EB_00000539_FBFDE_5_C07_EFB_59_F5_2e95645d57.jpg' height=600 width=800/>

There is a **proglacial lagoon** at the base that is formed from **glacier melt water** captured by the boundaries of the **lateral moraines**, **terminal moraines**, and **glacial till**. The importance of these glacial features on the landscape serve as an indicator for climate change with the Solheimajokull melting approximately 50 meters in length each year, which is similar to the length of an Olympic-sized swimming pool (Guide to Iceland, n.d.).

<img alt='10000000000006F60000053826CB88FA3EF45BE4.jpg' src='/api/images/medium_10000000000006_F60000053826_CB_88_FA_3_EF_45_BE_4_ff0f83f5eb.jpg' height=600 width=800/>

The glacier is covered in black ash from prior eruptions and black **tephra** originating from a 1918 eruption of Katla volcano, and historic photography from 1919 show that the original tephra thickness found on the ice after the eruption was 20-30 meters thick (Gudmundsson et al., 2021) (Photograph by Dianna Gielstra). That thickness is reduced at present to 30-35 cm with the tephra is visible in the lower outlet **glacier ablation** area, or the area where glacier melt and **recession** is found. (Gudmundsson et al., 2021). It should be noted that the black ash atop the glacial ice aids melting of the ice due to increased absorption of heat based on the **albedo** change (ice reflects solar energy while black rock absorbs solar energy).

<img alt='10000000000007680000058EEE6856F95ADBEA4F.jpg' src='/api/images/medium_10000000000007680000058_EEE_6856_F95_ADBEA_4_F_cede8ca0c0.jpg' height=600 width=800/>

Other notable physical features present are created by spatial variation of **longitudinal stresses**, or the forces pulling on the glacier (See figure below). That tension within the glacier in which the ice is being stretched creates longitudinal stress gradients. The **tensional stresses** of the ice movement and direction exceed the "brittle strength of ice" and **crevasses** form (Martini et al. 2001). Glacial geomorphology influenced by that tensional stress includes **bergschrund, transverse crevasses, marginal crevasses** as well as **ice ridges** and **ice caves**. 
Figure: Stresses within ice masses. Adapted from AntarcticGlaciers.org (n.d.)

![](/api/images/10000201000001160000012_CA_42_C27_F81_A1495_BD_f858ef198e.png)


<img alt='100002010000080000000509AD80434A892D25CA.png' src='/api/images/medium_100002010000080000000509_AD_80434_A892_D25_CA_3751599165.png' height=600 width=800/>

"Crevasse formation on valley glaciers"*.* Adapted from AntarcticGlaciers.org (n.d.)
As the glacial ice flows, it abrades the back face of the bedrock upstream of the bedrock slope (Martini et al., 2001). Embedded clasts on the stoss side (upslope) abrade the rock creating **striations** (Martini et al., 2001) (Photograph taken by Dianna Gielstra).

<img alt='100000000000058200000478F4E64C2F253A7D02.jpg' src='/api/images/medium_100000000000058200000478_F4_E64_C2_F253_A7_D02_55b359469c.jpg' height=600 width=800/>

Striations are visible on the rock in the foreground. The field leaders are pointing in the direction the glacier moved across the landscape as it advanced. 
The base of the proglacial lagoon has a river, Jökulsá á Sólheimasandi. The river empties into a **glacial outwash plain** with braided streams that empty into the ocean. 
Glacier Moraine Terminal moraines are composed of unsorted **till** moved by the glacier.The image below shows the material of the lateral moraine along the valley wall.(Photograph taken by Dianna Gielstra).



<img alt='10000000000003EB00000539083EC2F71EE3EB9E.jpg' src='/api/images/medium_10000000000003_EB_00000539083_EC_2_F71_EE_3_EB_9_E_b45ea4b8c0.jpg' height=600 width=800/>
The black sediments that are deposited are referred to as Sólheimasandur, or black sand desert. The movement of this material is in part a result of glacier outburst floods from the higher elevation mountain environments. The potential for geomorphic and **glacial hazards** in South Iceland's outlet glacier areas are higher as a bulk of the glacier has melted, forming hydrostatically sealed lakes trapped by ice and glacial till. A **Glacier Lake Outburst Flood (GLOF)** could result from an icefall/rockfall. Should this type of mass wasting event be large enough to send a tsunami-like wave, it would degrade the ice and moraine that currently dams the lake on the downhill slope (Gielstra et al., 2021). The wave might travel down the valley impacting both ecological and human communities. These flood events are known as *Jökulhlaup*, Icelandic word for GLOF and can result in death for anyone unfortunate enough to be present in the area when the glacial outburst flood occurs.

[Enter VR](/scenes/solheimajokull-iceland)

**Note:** The outwash from outlet glaciers empty into these landforms positioned in front of glaciers and valleys.

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  src="https://geoepic.app/wordle/play?sol=plain&lnk=/lessons/field-trip-escape-iceland/14"
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# GLOSSARY

**Ablation Zone** The section of a glacier or snowfield in which the melt exceeds accumulation.
**Accumulation Area** The part of the glacier located above the firn line. Accumulation of snow exceeds its melt. Known also as zone of accumulation or firn field.
**Albedo** The amount of Surface reflection of light.
**Braided Stream** A stream of multiple channels interwoven as the channels bifurcate and converge with flow. These streams are found in more shallow and broad channels that receive variability in flow and discharge.
**Chatter Marks** Crescentic gouges of fractured material removed from the bedrock because of rock fragments dragged under the ice of the moving glacier.
**Cirque** A deep, steep-walled basin formed by an alpine glacier, often circular or bowl-shaped
**Crevasse** Are cracks found at the glacier surface where the tensional stress generated with extended flow is greater than the strength of the ice.
**Firn**, a German term, translates to "last year snow", are more rounded ice crystals, compacted, and denser.
**Firn Line** Represents the transition between glacial ice and snow.
**Glacier** is a moving body of ice that formed on land from snow accumulation that transforms into dense glacial ice over a number of years.
**Glacial Ablation T**he lessened volume of a glacier because it melts.
**Glacial Forefront** The leading position on the landscape of glacier movement.
**Glacial Hazards** Hazards like mass wasting (rock fall), glacial flooding, etc. associated with glacier earth system processes.
**Glacial Melt Water** Water produced by glaciers melting.
**Glacial Hazards** Hazards like mass wasting (rock fall), glacial flooding, etc. associated with glacier earth system processes.
**Glacial Till** Rock debris formed from the process of plucking and grinding of the bedrock beneath a moving glacier
**Glacier Lake Outburst Flood (GLOF)** Flooding from a glacial lake created by melted glacial ice and associated with a breach of a glacier moraine.
**Glacial Outwash** Plain Sediments, sands, and gravel transported my meltwater from glaciers and deposited downstream in valleys that spread out over the landscape.
**Ice Caves** Caves that are made of, or contain, ice year round.
**Ice Ridges** Form landform that occurs when ice packs converge and pile up ice, ridges form.
**Head Wall** The steep cliff directly above a glacial cirque valley floor.
**Igneous (Magmatic) Rock** A type of rock formed by cooling magma/lava.
**Lateral Moraine** Composed of unsorted glacial till found at the sides margins of valley glaciers. 
**Lee Side** The downslope side
**Lithology** The study of rock types.
**Longitudinal Stress** forces pulling on the glacier that create longitudinal stress gradients. 
**Marginal Crevasse** Cracks in the glacier surface that form with a difference in speed of glacier movement from the sides of the glacier and its middle. These features exhibit rotation and chaotic morphology that is known as seracs (ice falls).
**Moraine** Accumulation of glacial sediment and rock moved and deposited by glaciers.
**Proglacial Lagoon** The water feature that forms just beyond the outer margin of the glacier.
**Proglacial Stream** The stream that forms from the meltwater just beyond the outer margin of the glacier.
**Recession** The glacier retreat because of melt.
**Serac** The ice falls that form at the glacier surface. 
**Splaying Crevasses** Cracks in the glacier surface that form when the glacier spreads out at the wider parts of the valley. The pattern tends to be radial at the tip of the glacier tongue.
**Stoss Side** The upslope side Glacial Striations Linear abrasions of the rock caused by the movement of rocks trapped in the underside of glacial ice when glaciers move over bedrock.
**Striations** Grooves or striations left on rocks caused by glaciers as they move across the surface.
**Tensional Stress** Stress from ice movement and direction that exceeds the "brittle strength of ice".
**Tephra** All pyroclastics produced by a volcano.
**Terminal Moraine** Composed of unsorted glacial till found at the glacier forefront at the maximum extent of the glacier.
**Terminal Moraine** Composed of unsorted glacial till found at the glacier forefront at the maximum extent of the glacier.
**Transverse Crevasse** Cracks in the glacier surface that form where a faster part of a moving glacier pulls away from a slower part of the glacier.
**Tyndall Effec**t Visible light scatters passes through a system containing discontinuities.

#### References:

Gudmundsson, M.T., Janebo, M.H., Larsen, G.P., Högnadóttir, T., Thordarson, T., Gudnason, J., &  Jönsdóttir, T. The explosive, balsaltic Katla eruption of 1918, south Iceland II. Isopach map, ice cap deposition of tephra and layer volume. Jökull, 71. [https://notendur.hi.is/mtg/pdf/2021_Jokull71_MTGetal_Katla1918_II.pdf](https://notendur.hi.is/mtg/pdf/2021_Jokull71_MTGetal_Katla1918_II.pdf)

Martini, P.I., Brookfield, M.E., & Sadura, S. (2001). Principles of Glacial Geomorphology and
Geology. Prentice Hall.

United States Geological Survey. (2016). Chapter A–2 (Figure 22B), Professional Paper 1386-A. https://pubs.usgs.gov/pp/p1386a/gallery2-fig22b.html





Study Area 4: South Region and Sólheimajökull!

---
id: '1csoIYmUI43Jw2mccSBbYyYtGC5DCcYjf-CgcSX_y7N8'
title: '5.Escape Iceland  Jökulsárlón'
date: '2022-10-09T13:21:34.733Z'
version: 263
lastAuthor: 'Dianna Gielstra <dianna.gielstra@prescott.edu>'
mimeType: 'text/x-markdown'
links:
  - 'https://beta.geoepic.app/lesson/field-trip-geodiversity-of-grinnell-sexton-%20and-sperry-glacier-basins'
  - 'https://www.wired.com/2011/01/vatnajokull-and-the-volcanoes-under-the-glacier-in-iceland/'
source: 'https://drive.google.com/open?id=1csoIYmUI43Jw2mccSBbYyYtGC5DCcYjf-CgcSX_y7N8'
wikigdrive: 'development'
---
Escape Iceland-Eastern Region
Gielstra, D., Cerveny, N.V., Gielstra, J. & Moorman, L.

## Welcome to the Southeastern Region and Jökulsárlón!

Your research team has made it to the southern region of Iceland! Great Job!! You have completed 4 out of 6 challenges toward your escape from the lava flows! At this site you will investigate a proglacial lagoon that empties into the Atlantic Ocean. Your team's task is to…

### Stop 5: Jökulsárlón

Jökulsárlón is positioned at the margin of Vatnajökull National Park, and is a **proglacial lagoon** with several **receding tongues** of **outlet glaciers** feeding into the lagoon proper. This area is found on the Southeastern Coast of Iceland with an outlet to the Atlantic Ocean and is susceptible to **tides** making these features **tidewater glaciers**. The surrounding outlet glaciers originate from the massive Vatnajökull Icecap that has an area of 8,100 kilometers2, and it has an estimated 3,300  kilometers3 of glacier ice covering the volcanoes: Grímsvötn, Öraefajökull and Bardarbunga (Gielstra, 2022; Klemetti., 2011). Vatnajökull is the largest remaining icecap in Iceland.

<img alt='1000020100000800000005A830B5ABF7D56F74FD.png' src='/api/images/medium_1000020100000800000005_A830_B5_ABF_7_D56_F74_FD_ea1b618992.png' height=600 width=800/>

(Map by Dianna Gielstra, 2022)
**Proglacial streams** are fed by the meltwaters of the glaciers, and the discharge is variable and punctuated by intervals of rapidity. The force of these waters can move large amounts of sediments and clasts. If the disturbance is frequent, then vegetation has greater difficulty covering these deposits making them vulnerable to wind and water erosion. Proglacial streams create complex networks of braided streams, referred to as a "valley train" within the outwash plain (Martini et al., 2001). 

Figure: Material deposited by proglacial streams. Map adapted from Martini et al.(2001).

<img alt='10000000000006750000048977A2E1392761EAD5.jpg' src='/api/images/medium_10000000000006750000048977_A2_E1392761_EAD_5_8409e78fab.jpg' height=600 width=800/>

These braided channels feed into the marine deltas forming subaqueous outwash fans (Photograph taken by Dianna Gielstra) (Martini et al., 2001). 

<img alt='10000000000006D6000001F76C6ECE20C0E9BCAA.jpg' src='/api/images/medium_10000000000006_D6000001_F76_C6_ECE_20_C0_E9_BCAA_ea914f1f67.jpg' height=600 width=800/>


Proglacial streams are composed of clasts of variable sizes, but source material determines the type, such as igneous, metamorphic, or sedimentary rock. Larger clasts tend to be abraded by the glacial and fluvial transport, thus "worked" with greater rounding (Martini et al., 2001). Glaciers pick up material and entrain it in the ice, moving the material along in the ice flow until the ice melts and the material is deposited.
Those **clasts** exposed to frost process and fracturing will have more angular and irregular shapes, or sharper shapes. These **outwash** deposit variability in terms of sizes and shapes are quite the assortment, and the stream flow strength determines the sorting; however, clay particles are not as prevalent in these areas (Martini, 2001).
Figure from Martini et al. (2001) showing A) deposit structuring along the outwash, B) outwash that ends in a delta and the structures of **foresets** versus **bottomsets**, and C) outwash underwater at the forefront of the glacier terminus.

<img alt='10000000000006C600000800AC7E1099AE927D18.jpg' src='/api/images/medium_10000000000006_C600000800_AC_7_E1099_AE_927_D18_eb446b5bfd.jpg' height=600 width=800/>

Adjacent to the glacier interface there are coarse deposits, gravel-sized are dominant. Where ice blocks may be dislodged from the glacier as it retreats and becomes buried. As these blocks melt, they form **kettles (**Photograph taken by Dianna Gielstra**)**. 
Figure: the image shows a kettle feature near the Jökulsárlón area. The excellent drainage of the porous rock in the area allowed the melted ice to drain leaving behind the depression. The individual at the bottom center of the feature shows the size and scale.

<img alt='100000000000080000000600D2CCE0A146CC76D3.jpg' src='/api/images/medium_100000000000080000000600_D2_CCE_0_A146_CC_76_D3_fec7c8173d.jpg' height=600 width=800/>

Further along the streams where the meanders split into the braided pattern, there is mixing of sand, gravel, and sediment. As the streams become broad in the outwash pain and steam power declines, sand and sediment are the dominant material. Some rippling occurs just under the water flow. At the end of the stream flow where stream power is at the weakest, the smallest particles of silt and clay are deposited in the **deltas** (Photograph by Dianna Gielstra).

<img alt='1000000000000659000004774FB073B8FB7B6696.jpg' src='/api/images/medium_1000000000000659000004774_FB_073_B8_FB_7_B6696_8bb0ea03fd.jpg' height=600 width=800/>

Because Jökulsárlón is a proglacial lagoon at the base of a tidewater glacier, the glacier terminus is partially underwater, or **subaqueous terminus**. The ice forms a cliff and **calves** into the water. As the glacier floats and is free of the bed, then it has extended beyond the** grounding line**. The glacier floats toward the sea and becomes thinner until it **calves** creating **icebergs**. 

<img alt='10000000000006D9000006815FE3442BC87CCB1A.jpg' src='/api/images/medium_10000000000006_D9000006815_FE_3442_BC_87_CCB_1_A_a6a8f04936.jpg' height=600 width=800/>

Image adapted from Martini et al. (2001) showing the difference between a floating and a tidewater terminus.
Because the tidewater glaciers are partially surrounded by ocean waters and exposed to the tides through the open outlet, waves generated by both the **calving** glaciers and by wind lead to further erosion. Such activity contributes to further weakening of the ice adjacent to, and within, the lagoon basin forming **icebergs** (Photographs taken by Dianna Gielstra). The glacial blue color of the ice is created by the Rayleigh Scattering (Tyndall Effect) as the ice crystals of the glacier absorb the visible spectrum colors of longer wavelengths, but allow the shorter wavelengths found in the blue part of the visible spectrum to pass through. Air bubbles and other disconformities in the glacier ice can further scatter the blue color.

<img alt='10000000000006F6000005382BA2618F97DC719B.jpg' src='/api/images/medium_10000000000006_F6000005382_BA_2618_F97_DC_719_B_8f0a575ab4.jpg' height=600 width=800/>


<img alt='100000000000080000000600531A87025B0A1BDB.jpg' src='/api/images/medium_100000000000080000000600531_A87025_B0_A1_BDB_ff5d4244eb.jpg' height=600 width=800/>

As the ice melts, **ice-rafting** of sediments leads to **glacio-lacustrine deposition**. Tidal currents and winds move icebergs toward the ocean, and during rapid glacier outburst flood events (GLOFs) additional erosion such as icefalls or accelerated melt, can lead to flooding events that**** push large amounts of water and icebergs through the channel, which have been known to repeatedly destroy the suspension bridge over the Jökulsárlón Lagoon (Photography by Dianna Gielstra).

<img alt='100000000000080000000600B7E10978F46368E1.jpg' src='/api/images/medium_100000000000080000000600_B7_E10978_F46368_E1_98cbc53c68.jpg' height=600 width=800/>

**[Enter VR](/scenes/diamond-beach)**

**HINT:** Material that is entrained in glaciers.

<iframe id="player" type="text/html" width="640" height="500"
  src="https://geoepic.app/wordle/play?sol=clast&lnk=/lessons/field-trip-escape-iceland/15"
  frameborder="0"></iframe>


### GLOSSARY

**Bergschrund** A crevasse located at the top of a mountain glacier adjacent to the head wall.
**Braided Stream** A stream of multiple channels interwoven as the channels bifurcate and converge with flow. These streams are found in more shallow and broad channels that receive variability in flow and discharge.
**Bottomsets** Sediment layers that are gently inclined and horizontally positioned. Formation occurs when finer sediments are carried out to the front of a delta.
**Calves** In marine or lacustrine environments it is the breaking away of icebergs from a glacier.
**Clasts** An individual fragment of rock (grain, constituent, or fragment) created by mechanical weathering of the rock.
**Delta** Alluvial deposits found at the mouth of a river or stream.
**Foresets** inclined and symmetrically positioned layers which are cross-bedded. Formation occurs when sediments are deposited after rolling down steep frontal slopes of a delta.
**Glacier** is a moving body of ice that formed on land from snow accumulation that transforms into dense glacial ice over a number of years.
**Glacier Blue** Ice crystals of the glacier absorb the visible spectrum colors of longer wavelengths found in the yellow to red part of the spectrum. The crystals allow shorter wavelenght\s to of the blue part of the spectrum to pass through. Air bubbles and other disconformities in the glacier ice can further scatter the blue color.
**Glacial Forefront** The leading position on the landscape of glacier movement.
**Glacial Hazards** Hazards like mass wasting (rock fall), glacial flooding, etc. associated with glacier earth system processes.
**Glacial Till** Rock debris formed from the process of plucking and grinding of the bedrock beneath a moving glacier
**Glacier Lake Outburst Flood (GLOF)** Flooding from a glacial lake created by melted glacial ice and associated with a breach of a glacier moraine.
**Grounding Line** The point inland where the glacier works on the bed, and the point toward the bay where the tidewater glaciers floats free of its bed.
**Kettle** A depression made from glacial drift deposition that is shaped like a bowl. The bowl had housed ice that melted leaving behind the depression.
**Icebergs** Land ice mass that detaches in water environments.
**Ice Cap** A cover of ice that forms a dome over the summits of mountain areas or flat areas. The feature spreads out radially because of the weight of the glacier ice. Size is limited to under 25,000 square kilometers.
**Igneous (Magmatic) Rock** A type of rock formed by cooling magma/lava.
**Outlet Glacier** An ice stream position between the ice cap and the ocean.
**Outwash** the sand and gravel moved by meltwater to be deposited at the terminal moraine or in the low-relief, plain beyond. The larger, coarser material is deposited nearest the glacier. The smaller, finer material, is deposited the farthest from the glacier.
**Proglacial Lagoon** The water feature that forms just beyond the outer margin of the glacier.
**Proglacial Stream** The stream that forms from the meltwater just beyond the outer margin of the glacier.
**Rayleigh Scattering** (Tyndall Effect) Visible light that scatters passing along a beam's path through an object or system containing discontinuities.
**Subaqueous Terminus** The conditions and processes occurring underwater that the end of the glacier is subject to the action. 
**Tidewater Glacier** Glacier that terminates into the ocean and has ice cliffs and ice falls.

### REFERENCE

Gielstra, D., Resler, L.M., Butler, D.R., Cerveny, N.V., & Gielstra, J. (2021). GeoEPIC: Field Trip:
Geodiversity of Grinnell, Sexton, and Sperry Glacier Basins. (2021). Geoheritage Pardee Keynote Symposium:  Geoheritage Pardee showcase of geodiversity, *Geological Society of America,* October 10-12, 2021. [https://beta.geoepic.app/lesson/field-trip-geodiversity-of-grinnell-sexton- and-sperry-glacier-basins](https://beta.geoepic.app/lesson/field-trip-geodiversity-of-grinnell-sexton-%20and-sperry-glacier-basins)
Klemetti, E. (2011). Vatnajökull and the volcanoes under the glacier in Iceland. Wired. [https://www.wired.com/2011/01/vatnajokull-and-the-volcanoes-under-the-glacier-in-iceland/](https://www.wired.com/2011/01/vatnajokull-and-the-volcanoes-under-the-glacier-in-iceland/)
Martini, P.I., Brookfield, M.E., & Sadura, S. (2001). Principles of Glacial Geomorphology and
Geology. Prentice Hall.






Study Area 5: Southeastern Region

---
id: '1eOqe6MQS9tfQu00lHzgRETw9fAC92b7va3tnTXtVKVQ'
title: '6. Escape Iceland -South: Hálsanefshellir sea cave, Reynisfjara Beach, and the Gardar cliff'
date: '2022-10-09T14:22:36.324Z'
version: 241
lastAuthor: 'Dianna Gielstra <dianna.gielstra@prescott.edu>'
mimeType: 'text/x-markdown'
links:
  - 'https://www.youtube.com/shorts/PFoG3PGYPN0'
  - 'https://www.youtube.com/watch?v=qmUP6l1I2Z4'
  - 'https://www.katlageopark.com/geosites/reynisfjall-reynisdrangar-reynisfjara/'
  - 'https://pubs.usgs.gov/pp/0131c/report.pdf'
source: 'https://drive.google.com/open?id=1eOqe6MQS9tfQu00lHzgRETw9fAC92b7va3tnTXtVKVQ'
wikigdrive: 'development'
---

Escape Iceland-Southern Region
Gielstra, D., Cerveny, N.V., Gielstra, J. & Moorman, L.

## Welcome to the Southern Region - Reynisfjara and the Hálsanefshellir Cave!

Your research team has made it to the southern region of Iceland! You have completed 5 out of 7 challenges toward your escape from the lava flows! At this site you will investigate a black sand beach and cave. The surf is too rough for the Iceland Search and Rescue (ICE SAR) teams to evacuate you from Reynisfjara and the Hálsanefshellir Cave, so your team has to make their way to the beach. Please be careful as volcanic events are not the only danger in this area. Your team's task is to learn as much as you can about the geodiversity of the final stop. Once you reach safety, your team will write a reflection about Iceland's geodiversity, and the processes that influence this diversity, to present your findings to your team leader. ***The stakes are high at these last two stops! Can you solve the Wordle code to reach safety and advance knowledge of this region? Good luck to you as you ESCAPE ICELAND!***

### Stop 6: Reynisfjara and the Hálsanefshellir Cave

In South Iceland a black sand beach called Reynisfjara is the site to what is considered one of the most beautiful sea caves. The geology is interesting because a subvolcanic eruption created a 340 m high tuff mountain (Katla Geopark, n.d.). The layering of the surrounding geology is more complex with variation in deposits of tuff, pillow lava, and columnar basalt features (Katla Geopark, n.d.).

<img src="/api/images/medium_1000000000000800000005_A83_A9131040_AD_19780_342bd46ce9.jpg" alt="1000000000000800000005A83A9131040AD19780.jpg">

The black sand beach is produced from the ocean processes of wave action and erosion of the basalt in the area that was produced by the Katla volcanic eruption. The basalt parent material characterizes the beach material and color. Beach pebbles are produced from the igneous rock and wave action moving the rock fragments back and forth produce flat, elliptical shapes (Wentworth, 1922) (Photographs taken by Dianna Gielstra).

<img src="/api/images/medium_10000000000006000000080019_FA_40_A68_F994_D85_29f9adac02.jpg" alt="10000000000006000000080019FA40A68F994D85.jpg">
<img src="/api/images/medium_100000000000060000000800_BC_2_CD_20_A164_C90_C1_90782faa75.jpg" alt="100000000000060000000800BC2CD20A164C90C1.jpg">

The beach is sorted with the uppermost portion of the beach having a greater amount of the larger sized-smoothed pebbles.The material becomes finer as the waves draw the finder material to the lower parts of the shore (Photograph by Dianna Gielstra)..

<img src="/api/images/medium_10000000000008000000060041_ABCEB_5_C6_C24_D1_C_c73d7b9a04.jpg" alt="10000000000008000000060041ABCEB5C6C24D1C.jpg">

The Gardar Cliff has a pyramidal structure formed by the **columnar basalt** at this location (Photograph by Dianna Gielstra). As magma cools. Slower cooling of the magma over time causes the surfaces of the columnar joints to contract and crack along the surfaces. The contraction takes the form of one of the most efficient shapes in nature, polygons.

<img src="/api/images/medium_10000000000006000000080009155_E548_F3_B1_FAC_0162b798b7.jpg" alt="10000000000006000000080009155E548F3B1FAC.jpg">

**Fun Fact:** Columnar basalt may result in pentagon (5-sided structures) or hexagon shapes (6-sided structures), but natural forms can vary with triangular, or wedge shapes (3-sided) or even seven sides sides but have as few as 3 and heptagon (7-sided shape) (Volcano World, n.d.).

This structure and definition in the columnar basalt that is more even and straight is often referred to as a colonnade. In this location the colonnade is influenced by repetitive wave action that eroded the rock and formed a cave, known as Hálsanefshellir (Photograph taken by Dianna Gielstra).

<img src="/api/images/medium_10000000000008000000060081_F28_C7340_ADFD_2_C_ae35ee7ee7.jpg" alt="10000000000008000000060081F28C7340ADFD2C.jpg">

It is one of the most beautiful examples of this type of cave. The structure of the cliff is an important habitat for seabird colonies.

[Wave action along the beach near Renisfjara](https://www.youtube.com/shorts/PFoG3PGYPN0)

Inside the Hálsanefshellir Cave offers a unique view of the basalt structure. (Photograph taken by Niccole V. Cerveny)

<img src="/api/images/medium_10000000000008000000060017_DBFA_5_A66_D1_F44_C_2edcd011ea.jpg" alt="10000000000008000000060017DBFA5A66D1F44C.jpg">

[Enter VR](/scenes/halsanefshellir-cave)

These tidal environments are high energy, and the **waves** create a large array of features. The consistent impact of waves against the joints and cracks in the rock loosens the material and forms <strong>sea caves</strong>. Continued erosion forms <strong>arches</strong>, and when these collapse only the\*\* pillars\*\* remain (National Park Service, n.d.). Reynisdrangar **stacks** have similar geology as Reynisfjara Beach. The features are approximately 66 meters in height (Katla Geopark,n.d.).
Figure: Physical features created by **coastal erosion** (National Park Service, n.d)

<img src="/api/images/medium_10000000000005_EE_000003_AF_8_E8_E4_C0_AD_615_A8_C0_f8998474e5.jpg" alt="10000000000005EE000003AF8E8E4C0AD615A8C0.jpg">

<img src="/api/images/medium_100000000000080000000600_D66077_CD_06_D8_F56_C_af845dcd60.jpg" alt="100000000000080000000600D66077CD06D8F56C.jpg">

Humans have attached stories to these <strong>sea stacks</strong>(Photograph by Niccole V. Cerveny). **Trolls** are a part of the story-telling tradition in Iceland to describe and explain these <strong>physical features</strong>. In this area, it is said that these stacks are two trolls frozen in place by sunlight as they worked to move a ship to shore.

Figure: Signage warning tourists of sneaker waves at Renjiasfara Beach (Photograph by Dianna Gielstra).

<img src="/api/images/medium_100000000000060000000800_CE_8_D4_D3942_CC_2_ABD_99bf46c8a8.jpg" alt="100000000000060000000800CE8D4D3942CC2ABD.jpg">

Through the ocean processes of wave action, the waves crash into the shores and the cliff creating a narrow beach making this area dangerous with the presence of "<strong>sneaker waves</strong>" (Video from Katla Geopark, n.d.).

# [Waves Sneak Up Reynisfjara Beach in Iceland and Knock Over Tourists](https://www.youtube.com/watch?v=qmUP6l1I2Z4)

[Enter VR](/scenes/reynisfjara-beach-and-the-gardar-cliff)

Your team has finished collecting the information you need to report on Iceland's geodiversity as you navigated to safety. Congratulations! The vessel is just off shore to collect you. BEWARE! Reynisfjara is Iceland's most dangerous beach. Please don't get swept out to sea. Stay alert, solve the final Wordle code, and get you and your team to safety.

### Solve this Final wordle code and you have ESCAPED ICELAND!

**Hint:** The erosional forces that shape coastlines.

<iframe id="player" type="text/html" width="640" height="500"
  src="https://geoepic.app/wordle/play?sol=waves&lnk=/lessons/field-trip-escape-iceland/17"
  frameborder="0"></iframe>

## GLOSSARY

**Arch** A natural landform influenced by weathering and erosion processes to form an arch.

**Columnar Basalt** Basalt that has columnar jointing and polygonal shapes.

**Colonnade** A more uniform pattern of columnar structure, normally found at the bottom of the lava flow that is known as the entablature.

**Physical Feature** An abiotic feature on the surface of the earth.

**Pillar** A natural rock feature that is shaped like a pillar.

**Sea Stacks** A natural rock feature/ landform created when the foreland is eroded by coastal wave erosion.

**Sneaker Wave** A wave with greater energy that can surge onto shore with great force extending far beyond normal foam line. These waves have carried people out to see.

**Trolls** A mythical lifeform of Norse and Icelandic folklore at odds with humans and lives in remote, rocky places.

**Wave Action** Wave energy that works on coastal shorelines through erosion and deposition processes.

## REFERENCE

# Katla Geopark. (n.d.). Reynisfjall, Reynisdrangar, Reynisfjara. [https://www.katlageopark.com/geosites/reynisfjall-reynisdrangar-reynisfjara/](https://www.katlageopark.com/geosites/reynisfjall-reynisdrangar-reynisfjara/)

Katla Geopark. (n.d.). [Waves Sneak Up Reynisfjara Beach in Iceland and Knock Over Tourists](https://www.youtube.com/watch?v=qmUP6l1I2Z4)
https://www.katlageopark.com/safe-travel-in-iceland/

National Park Service. (n.d.). Sea cave development. https://www.nps.gov/subjects/caves/sea-or-littoral-caves.htm#:\~:text=Sea%20caves%20or%20littoral%20caves,nearly%20every%20type%20of%20rock.

Wentworth, C.K. (1922). The shapes of beach pebbles. <em>U.S. Geological Survey Bulletin</em>, 730:91-114. [https://pubs.usgs.gov/pp/0131c/report.pdf](https://pubs.usgs.gov/pp/0131c/report.pdf)

Volcano World. (n.d.). Columnar jointing. https://volcano.oregonstate.edu/columnar-jointing

Study Area 6: South Region Reynisfjara and Hálsanefshellir Cave

---
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# GLOSSARY

**Accumulation Area** The part of the glacier located above the firn line. Accumulation of snow exceeds its melt. Known also as zone of accumulation or firn field.
**Arch** A natural landform influenced by weathering and erosion processes to form an arch.
**Glacial Ablation T**he lessened volume of a glacier because it melts.
**Ablation Zone** The section of a glacier or snowfield in which the melt exceeds accumulation.
**Albedo** The amount of Surface reflection of light.
**Ash Deposits** A mix of ash, glass, and fragments of rock ejected from the volcano depositing on the landscape.
**Basalt** An igneous rock with fine grains and contains plagioclase feldspar, olivine, and pyroxene minerals.
**Bergschrund** A crevasse located at the top of a mountain glacier adjacent to the head wall.
**Bottomsets** Sediment layers that are gently inclined and horizontally positioned. Formation occurs when finer sediments are carried out to the front of a delta.
**Braided Stream** A stream of multiple channels interwoven as the channels bifurcate and converge with flow. These streams are found in more shallow and broad channels that receive variability in flow and discharge.
**Breccia** Rock composed of coarse, angular pieces. It can be formed through sedimentary rock processes, or created with grinding forces around faults.
**Chatter Marks** Crescentic gouges of fractured material removed from the bedrock because of rock fragments dragged under the ice of the moving glacier.
**Cirque** A deep, steep-walled basin formed by an alpine glacier, often circular or bowl-shaped
**Columnar Basalt** Basalt that has columnar jointing and polygonal shapes.

**Colonnade** A more uniform pattern of columnar structure, normally found at the bottom of the lava flow that is known as the entablature.
**Continental Rift** An opening in the lithosphere formed as plate boundaries thin as the plate boundaries pull apart.
**Continental Rift Jump:** Since the whole divergent boundary does not move at a similar rate, the boundary will develop transform faults (slide side by side) so that the part that is opening can move independently of the entire boundary. This causes "jumps" within the rift. On a tectonic map, these appear like stitches in a nonlinear cut.
**Convective Currents** Between the core and crust of the earth with relatively hotter and colder areas that create circulation cells within the molten asthenosphere/mantle of the earth
**Crevasse** Are cracks found at the glacier surface where the tensional stress generated with extended flow is greater than the strength of the ice.
**Divergent Plate Boundaries** Location in which the tectonic plates are pulling apart from one another.

**Fault:** Cracks or fissures within the earth's crust
**Firn**, a German term, translates to "last year snow", are more rounded ice crystals, compacted, and denser.
**Firn Line** Represents the transition between glacial ice and snow.
**Fissure Swarms** Individual volcanic fissures arranged so that these appear to emerge from volcanic centers out among the rift zone (within 100 km, bi-directionally).
**Folds** Deformation of rock or strata that creates bending.
**Fracture** A rock that has a crack, tear, or fault because of stress forces. 

**Fumarole** A vent in areas with volcanic activity in which gasses escape.
**Geology** The study of the earth through rocks, including geologic features, geologic time for history, formations, and processes.
**Geodiversity**  The various rocks, minerals, soil, and fossils that are found on the landscape as well as describes the processes that form those patterns.
**Geoheritage** Geological features that have value to humans in terms of science, education, aesthetic, and culture.
**Geomorphic Features** Landforms found on both the bathymetric and topographic surface of the earth.
**Geomorphology** The study of physical features found on earth's surface and the processes that formed these secondary geological structures.
**Geothermal System** A geological setting where earth's internal heat flows to the surface and creates hot water and steam.

**Geothermal** **Vent** A crack or hole in the earth through which hot water and gasses can escape.
**Geysers** A natural water source that is heated by geothermal energy resulting in release as a fountain of water and steam into the air. This release may occur with regular intervals.
**Glacier** is a moving body of ice that formed on land from snow accumulation that transforms into dense glacial ice over a number of years.
**Glacier Blue** Ice crystals of the glacier absorb the visible spectrum colors of longer wavelengths found in the yellow to red part of the spectrum. The crystals allow shorter wavelenght\s to of the blue part of the spectrum to pass through. Air bubbles and other disconformities in the glacier ice can further scatter the blue color.
**Glacial Geomorphology** The study of how glacial masses (ice sheets, alpine glaciers, valley glaciers, etc.) influence landforms and the processes that form them.
**Glacial Forefront** The leading position on the landscape of glacier movement.
**Glacial Hazards** Hazards like mass wasting (rock fall), glacial flooding, etc. associated with glacier earth system processes.
**Glacial Melt Water** Water produced by glaciers melting.
**Glacial Till** Rock debris formed from the process of plucking and grinding of the bedrock beneath a moving glacier
**Glacier Lake Outburst Flood (GLOF)** or **_Jökulhlaup_** Flooding from a glacial lake created by melted glacial ice and associated with a breach of a glacier moraine.
**Grounding Line** The point inland where the glacier works on the bed, and the point toward the bay where the tidewater glaciers floats free of its bed.
**Kettle** A depression made from glacial drift deposition that is shaped like a bowl. The bowl had housed ice that melted leaving behind the depression.
**Head Wall** The steep cliff directly above a glacial cirque valley floor.
**Hot Spots/Mantle Plumes** Fixed areas within the earth's mantle in which hotter magma rises to the surface and thins the lithosphere to the point of volcanic activity.

**Hyaloclastite** Tuff-like deposit. Material created as basalt flowed under water from the melted glacier.
**Icebergs** Land ice mass that detaches in water environments.
**Ice Cap** A cover of ice that forms a dome over the summits of mountain areas or flat areas. The feature spreads out radially because of the weight of the glacier ice. Size is limited to under 25,000 square kilometers.
**Ice Caves** Caves that are made of, or contain, ice year round.
**Ice Ridges** Form landform that occurs when ice packs converge and pile up ice, ridges form.orm landform that occurs when ice packs converge and pile up ice, ridges form.
**Igneous (Magmatic) Rock** A type of rock formed by cooling magma/lava.
**Lava** Molten rock that escapes is transported to earth's surfaces when it is extruded through vents and fissures.
**Lava Domes** Mounds formed from slow-moving, viscous lava protrusions.
**Lava Flows** Molten rock streams that are released during eruptions from volcanic vents.
**Lateral Moraine** Composed of unsorted glacial till found at the sides margins of valley glaciers. 
**Lithology** The study of rock types.
**Lithosphere**The solid surface of the earth, above the mantle
**Longitudinal Stress** forces pulling on the glacier that create longitudinal stress gradients. 
**Mantle Plumes/Hot Spots** Fixed areas within the earth's mantle in which hotter magma rises to the surface and thins the lithosphere to the point of volcanic activity
**Marginal Crevasse** Cracks in the glacier surface that form with a difference in speed of glacier movement from the sides of the glacier and its middle. These features exhibit rotation and chaotic morphology that is known as seracs (ice falls).
**Mid-Ocean Ridge** A mountain range found on the ocean floor formed by seismic activity. Elevation of the range is approximately 1 to 3 km and has a width of 1500 km in height. Length for the total range is 84,000 km (Parker, 1994).
**Móberg** Palogonite tuff, basalt that has undergone transformation because of contact with water. The exposure can create lighter colored, thinner material.
**Moraine** Accumulation of glacial sediment and rock moved and deposited by glaciers.
**Mudpot** hotspring that contains mud and is found in geothermal areas. Sulphurous and rich in minerals that can create multiple colors. Sometimes these are referred to as "painted pots".
**Outlet Glacier** An ice stream position between the ice cap and the ocean.
**Outwash** the sand and gravel moved by meltwater to be deposited at the terminal moraine or in the low-relief, plain beyond. The larger, coarser material is deposited nearest the glacier. The smaller, finer material, is deposited the farthest from the glacier.
**Peninsula** Land extending into the water from the mainland; mostly surrounded by water.
**Pillar** A natural rock feature that is shaped like a pillar.
**Pillow Lava** Lava formed under water, cools into ellipsoidal shape near the vent. Looks more rounded and smooth.
**Pleistocene** geologic epoch of the Quaternary period of the Cenozoic representing approximately 0.8 million years before present. 
**Outlet Glacier** An ice stream position between the ice cap and the ocean.
**Outwash** the sand and gravel moved by meltwater to be deposited at the terminal moraine or in the low-relief, plain beyond. The larger, coarser material is deposited nearest the glacier. The smaller, finer material, is deposited the farthest from the glacier.
**Physical Feature** An abiotic feature on the surface of the earth.
**Proglacial Lagoon** The water feature that forms just beyond the outer margin of the glacier.
**Proglacial Stream** The stream that forms from the meltwater just beyond the outer margin of the glacier.
**Pyroclastics** Rocks and rock fragments formed and ejected from volcanoes during explosive volcanic events.
**Pyroclastic Flows** Ash flow ejected from volcano that moves down slope with speed.
**Rayleigh Scattering** (Tyndall Effect) Visible light that scatters passing along a beam's path through an object or system containing discontinuities.
**Rift Segments** A series of separate segments of the rift. These share a geometry based on the downward placement of the crust at these locations.
**Rift Valley** The central valley in the crest of the mid-oceanic ridge.
**Rotational Slump** A form of mass wasting or movement in which gravity helps to pull down or "slump" earth materials at the surface in a rotation supported by underlying bedrock

**Sea Stacks** A natural rock feature/ landform created when the foreland is eroded by coastal wave erosion.
**Serac** The ice falls that form at the glacier surface. 
**Sinter** Precipitate from mineral springs that create hard deposits of silica.

**Sneaker Wave** A wave with greater energy that can surge onto shore with great force extending far beyond normal foam line. These waves have carried people out to see.
**Splaying Crevasses** Cracks in the glacier surface that form when the glacier spreads out at the wider parts of the valley. The pattern tends to be radial at the tip of the glacier tongue.
**Spouts** Liquid under force and pressure that spews from a vent.
**Stoss Side** The upslope side Glacial Striations Linear abrasions of the rock caused by the movement of rocks trapped in the underside of glacial ice when glaciers move over bedrock.
**Subaqueous** Formation or process positioned underwater.
**Subglacial Volcano** A volcano positioned beneath a glacier or ice sheet.
**Subaqueous Terminus** The conditions and processes occurring underwater that the end of the glacier is subject to the action. 
**Striations** Grooves or striations left on rocks caused by glaciers as they move across the surface.
**Tectonic Plates** individual lithospheric plates move through divergence, convergence, or transform motion.
**Tensional Stress** Stress from ice movement and direction that exceeds the "brittle strength of ice".
**Tephra** All pyroclastics produced by a volcano.
**Tidewater Glacier** Glacier that terminates into the ocean and has ice cliffs and ice falls.
**Tindars:** a small mound of volcanic material that collects in the void space beneath the ice as the volcanic activity melts the underside of the glacier.
**Terminal Moraine** Composed of unsorted glacial till found at the glacier forefront at the maximum extent of the glacier.
**Transverse Crevasse** Cracks in the glacier surface that form where a faster part of a moving glacier pulls away from a slower part of the glacier.
**Trolls** A mythical lifeform of Norse and Icelandic folklore at odds with humans and lives in remote, rocky places.

**Tyndall Effect** (Rayleigh Scattering) Visible light that scatters passing along a beam's path through an object or system containing discontinuities.
**Volcanism** Magma and gas movement from earth's interior to earth's surface.
**Wave Action** Wave energy that works on coastal shorelines through erosion and deposition processes.


## REFERENCE


Parker, S.P. (1994). *McGraw-Hill encyclopedia of science & technology.* New York :McGraw-Hill



GLOSSARY

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