Artistic portrayal of the Makanaka-age glacier on Hawai’i as it advanced towards its maximum extent — all on top of the Mauna Kea volcano. Art work by ASU student Alexis Ruiz, using Google Earth imagery.

Lab Title Fire and Ice on the Big Island of Hawaii: Volcanic Hazards and Volcano Modification by Landform Processes

Lab Summary The sculpting of Earth’s relief by volcanic processes and the erosion of that relief is a major topic in physical geography’s study of earth surface processes. The Big Island of Hawaii experiences both sets of processes on timescales that can be studied in a basic physical geography class. Thus, you will observe how the Hawaiian volcanoes evolve and evaluate a case of volcanic hazard for the Hualalai Volcano. You will also explore how glaciers work to erode the tallest of the volcanoes – all within a geovisualization where you interact with the physical geography as an avatar in a video game.

Reason to select this lab

In addition to providing points in the multi-step lab category, it uses an innovative way to analyze landforms: a geovisualization that is like a video game. There is a cost, though, of $15. Also, you will need a laptop or a desktop Windows or Mac Computer that has at least 4 GB RAM (ideally 8 GB).

Useful maps to download – these are not

National Park Service map of the Big Island:https://www.nps.gov/carto/hfc/carto/media/HAVOmap4.jpg

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required, but helpful to some students

NPS map of Kilaueahttps://www.nps.gov/carto/hfc/carto/media/HAVOKilaueamap.jpg

Computer program used in this lab

You will be given instructions later on how to purchase the geovisualization game environment in canvas. In the geovisualization, you are an avatar character able to investigate volcanic, river valley and glacial features to complete the lab. Since this lab is optional, you do not have to purchase the geovisualization for this course.

SQ general studies learner objectives

Students analyze geographical data using the scientific method, keeping in mind scientific uncertainty. Students also use mathematics in analyzing rates to change in the landscape. Students also work to enhance their understanding of fundamental principles of dynamics and mechanics governing the behavior of matter in physical systems.

Science & Society learner objectives

This lab meets three learner goals for this requirement in the context of volcanic hazards. In studying volcanic hazards associated with the Hualalai Volcano, they analyze a case study on the reciprocal relationship between science and society. In doing so, they develop a critical understanding western science (e.g. using a statistical distribution to predict a hazard). Then, they formulate and communicate a view of the hazard for the people living downslope of the volcano. Thus, this is local case study whose basic parameters follow other societal hazards associated with the processes studied in this landforms class.

Organization of the lab

Section 1. Preface: Fire and Ice on the Big IslandSection 2. Overview of the labSection 3. Extra background materials.Section 4. Geovisualization purchasing and playing

TABLE OF CONTENTS OF THIS DOCUMENT1. Preface: Fire and Ice on the Big Island: a case study in how volcanic and glacial processes reshape the surface of Earth?

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2. Geovisualization: purchasing and playing 53. Overview of lab activities 64. Background information 85. Step-by-Step Guidance in answering questions for the laboratory. 29

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Space shuttle view of Hawai’i

1. Preface: Fire and Ice: Volcano hazards, glaciation, and valley development on the Big island of Hawai’i

The Big Island of Hawai’i is a special place for physical geographers to study. There exists such a wide range of climates, all while the geology of basalt lava rock type remains pretty constant. For example, warm desert conditions exist on the western sides of the Hualalai, Mauna Kea, and Kohala shield volcanoes, and cold desert conditions on top of Mauna Kea and Mauna Loa volcanoes. Physical geographers have studied everything from coastal erosion to incision of stream valleys using the variety of conditions on the Big Island. Since physical geographers typically love fieldwork, a plus is the lack of poisonous snakes.

Unlike other sciences that task you with analyzing one focused field such as cellular biology, inorganic chemistry, or physics – physical geography concentrates on six general areas of science to try to understand better the great variety of environmental conditions that exist at Earth’s surface. Physical Geography was the world’s first environmental science field, well before everything split off, and it remains focused on interconnections as displayed in the following diagram.

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Image compiled by Ron Dorn to show how all of the elements of physical geography come together to analyze the nature Earth’s surface

A very large part of geography involves connections between science & society. This is true for geomorphology as well. In the context of the Big Island of Hawaii, this lab has a large component where you examine volcanic hazards associated with the Hualalai Volcano that towers over the Kona coast. You use a scientific approach to study these volcanic hazards and think about their implications for people in the pathway of possible future lava flows. These questions are of a scale appropriate for a videogame geovisualization that encompasses the entire Big Island of Hawaii. The geovisualization looks and plays like a videogame.

There is a caveat about the lab: There is no doubt that an online lab about the Big Island is missing out on our five traditional sense of sight (and the changes in lighting), smell and feel the trade winds on your face, the taste of trail and camping food, the smell of plants, and touching of different volcanic rock textures. In the end, you will just have to experience these in Hawai’i for yourself.

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2. The video game geovisualization: purchasing, downloading, and playing

There is a page for this lab in canvas that explains about how to purchase, download and play the geovisualization. However, there are a few issues that I want to emphasize right away:

YOU DO NOT HAVE TO DO THIS LAB – please understand that you do not have to do this lab. It is not a requirement for the class. This lab is just one of the assignments in the multi-step lab category.

THERE IS A COST – The geovisualization was developed by Two Bent Coppers, and it will cost you $15 to purchase and download the geovisualization.

YOU MUST HAVE A GOOD COMPUTER (laptop or desktop) to play the geovisaulization – Window 8 and El Capitan are the lowest operating systems that will work. Your computer must have AT LEAST 4 GB of RAM and be a 64-bit machine.

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3. Overview of lab activitiesThe purpose of this section is to provide you an overview of the activities you will

complete. Before you dig into the lab, you are also welcome to learn extra background information about the Big Island of Hawai’i in the next section. The developers of this lab assume that you have this background knowledge already. Thus, if you are not familiar the material in section 3, you will need to read that section to complete the lab successfully.

3.1 Parts of this lab. This lab has questions divided into different parts.

Part 1: Volcano Basics

Part 2: Volcanic Hazards

Part 3: Science & Society Essay on Volcanic Hazards

Part 4: Glaciation of Mauna Kea: Will there be another one?

Part 5: River Valley Incision: how long does it take to make a river valley in Hawai’i?

3.2. The study area and the scale of study

The entirely of the Big Island is too much to analyze at a scale where you can see the sorts of features that would be of interest to you on the ground. It just is not possible to include everything in a videogame at a large scale of even 1:100 (1 length on the ground to 100 lengths on the map). There is just too much detail. Besides, sometimes its possible to lose sight of the forest if you are too buried in the roots of the trees. The big-area (small scale) patterns in physical geography would get lost.

Thus, all of the laboratory activities will be at a scale where you can only zoom in just so close. High spatial resolution is not what this laboratory covers, but rather bigger-sized features and processes.

The two graphics below show a wonderful map designed and produced by the National Park Service and a famous Landsat 7 mosaic produced by NOAA. Both of them show the study area of this lab.

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4. Background material related to the lab

The developers of this lab piloted the lab activities with students, who ended up asking a lot of questions about different aspects of the Big Island and who found the material in this section useful in completing the lab. While some wanted to know more about topics not covered in this lab like coral reefs and rainforests, most of the questions were asking for details that they needed to answer the questions in the lab. While the information in this section occurs in GPH 111 lectures and readings, the relevant information is concentrated in this section covering information about volcanoes and the glacial history of Hawai’i.

4.1. Background on Volcanoes on the Big Island

The Big Island has five major shield volcanoes, where this map is courtesy of the National Park Service.

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There are thousands of smaller volcanoes, for example the Pu‘u ‘O‘o volcano. This volcano grew on the flank of Kilauea volcano and it grew and collapsed over decades. These repeat images show the basaltic cone in 1992 the reached 255 m above the surrounding topography. It then collapsed and developed a lava shield that continued to accumulate.

However, this lab focuses on the five major shield volcanoes on the Big Island.

Image courtesy of the National Park Service and the USGS.

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All of the “big 5” volcanoes are called shield volcanoes, because they have the shape (in profile) of a shield used in battle. The shape is evident in this famous painting of a Kilauea lava lake and a snow-capped Mauna Loa shield in the background:

Image courtesy of the National Park Service.

The Hawaiian Islands are in the middle of the Pacific plate, as shown in this National Park Service graphic. Whereas most volcanic activity is associated with divergent and convergent boundaries, the Hawaiian Islands sit on a hot spot in the mantle.

Image courtesy of the National Park Service.

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This graphic from the U.S. Geological Survey shows how the Kilauea volcano is “plumbed” to this hot spot

The Pacific Plate has been moving over this hot spot for tens of millions of years, producing first the Emperor chain and then the Hawaiian chain of volcanoes.

Image courtesy of the National Park Service and the USGS.

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This is another perspective that shows the topography of the Pacific floor in relationship to these two volcanic chains. The reason for the sudden shift in direction has to do with when the Laramide mountain building phase ended about 50 million years ago and plate motion changed. The Laramide orogeny was when the Colorado Plateau (and the area of the Grand Canyon) was uplifted from its former position as an inland sea.

Image courtesy of the National Park Service and the USGS.

Almost all of the volcanoes in these chains have sunk below the surface when they have been disconnected from the hotspot. The Hawaiian Islands are also sinking, but the Big Island is still growing from new lava.

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STAGES OF HAWAIIAN VOLCANOES: This lab tasks you with virtual “field work” to find evidence of the stage of evolution of the different volcanoes on the Big Island with the following graphics by the U.S. Geological Survey to illustrate the stages.

The preshield stage is when a volcano starts to build from the ocean floor, slowly and infrequently. The Lo‘ihi seamount to the south of Kilauea volcano is an example.

Images courtesy of the USGS.

The second stage is called the shield-building stage. It has the most voluminous volcanic eruptions that grow the volcano well above sea level. Over 90% of a Hawaiian volcanoes volume is produced in this stage. There’s so much lava erupting that it depresses the ocean crust. In this graphic, the depression is shown by arrows and also former sea level evidence (strandline) that has been pushed beneath the ocean surface.

In addition to the shield-shape and the big volume, the shield stage has rift zones. A nice picture of an eruptive rift zone is this March 25, 1984 image of the eruption of Mauna Loa.

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https://volcanoes.usgs.gov/observatories/hvo/hvo_volcano_watch.html?vwid=385

This U.S. Geological Survey map shows some of the major rift zones of Mauna Loa and Kilauea volcanoes.

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Images courtesy of the USGS.

The fourth stage or post-shield stage is where the volcano stops producing voluminous eruptions and starts to generate the sorts of volcanic features that make the volcano a bit steeper on top. Mostly, the post-shield features are lots of cinder cones and thick a’a lava flows that pile up near the summit and in flank rift zones.

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This is a famous picture taken at the International Space Station of Mauna Kea with the lightning showing the Cinder Cones.

https://earthobservatory.nasa.gov/images/87059/mauna-kea-volcano-hawaii The last known time that Mauna erupted was about 4500 years ago, but neighboring Hualalai volcano erupted historically, as seen in this USGS map.

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Images courtesy of the USGS

A post-shield Hawaiian volcano typically goes dormant for awhile (tens to hundreds of thousands of years) and then gets active in the 4th stage called “rejuvenated stage”. The volcano has moved well away from the mantle hot spot, and eruptions are isolated, relatively small, and infrequent. Diamond Head Crater on O’ahu Island, about a half-million years old, is an example. This is the last stage involving volcanic activity.

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After the rejuvenated stage comes the Erosional Stage.

Hawaiian volcanoes erode and also subside due to the weight of the lava on the ocean crust. The erosion involves rock decay (weathering), the development of spectacular river valleys, and landsliding as illustrated here where the basic shape of the shield volcano is hard to recognize.

Image courtesy of TM Oberlander

Sometimes, the landsliding can be spectacularly large where the sides of the volcanoes collapse out onto the ocean floor. This is a map of some of these collapses from the U.S. Geological Survey. The islands also sink in response to the loading of lava on the ocean crust, and hence the fate of a Hawaiian volcano is always to sink beneath the surface.

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Image courtesy of USGS.

Just before the volcano goes under, it can become a coral atoll. As the volcanoes sink, coral reefs can form on top of the sinking volcano. Coral then forms on tops of older dead coral, as the islands continue to sink. This is Jure atoll, 6 miles wide and the oldest part of the Hawaiian Island chain.

Image courtesy of the USGS.

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This is a complicated diagram that summarizes the stages of Hawaiian volcanoes from the U.S. Geological Survey. It is sideways here so you can see more detail.

Image courtesy of the USGS.

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4.2. Background on the Glacial Ice Cap on Mauna Kea

The Big Island had glaciers on top of its highest peaks several times during the last 200,000 years. It may have had glacial ice caps earlier, but the evidence has been lost. Any aliens visiting Earth might about 20,000 years ago might have looked down at Mauna Kea, and the scene might have looked like this artistic reconstruction:

Artistic vision of what Mauna Kea may have looked like as the glacier was expanding near its maximum during last glaciation around 20,000 years ago, created by ASU student Alexis Ruiz on a base map from Google Earth.

The study of past glaciations and their impact on the planet is an important topic in physical geography, because the ice ages left a major imprint all over Earth. In the last 2.5 million years, our planet experienced many different glacial advances, followed by warms ups and an interglacial period. We are now in one of those interglacial periods.

One way that physical geographers study past glaciations is to reconstruct the change in the Equilibrium Line Altitude (ELA) of a glacier in the past compared to today. The ELA is the elevation where accumulation of snow is balanced by the ablation (loss of ice by melting, sublimation (ice to water vapor), or calving (icerbergs into the ocean or lake). Above the ELA, more snow accumulates than ablates, and loss of ice below the ELA is faster than accumulation.

The elevation of the ELA is sensitive to climatic change. A change to a drier and warmer climate will raise the ELA, while a change to a wetter and cooler climate will lower the ELA. The graphic below illustrates the basic idea of the ELA in A, while

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graphics B and C illustrate how ELAs get lower the further you get to the poles and also how they lowered in elevation during the Last Glacial Maxima (LGM) that took place about 20,000 years ago.

https://www.researchgate.net/profile/Patricia_Ciccioli

Another way to think about the Equilibrium Line Altitude is in terms of the processes that lead to glacial accumulation and loss. The accumulation of glacial ice requires snow. This does occur at present, as evidenced by the International Space Station photograph of Mauna Kea after a winter snow storm below. However, such snowfall events are rare today. However, for glaciers to grow on Mauna Kea, they must have been much more frequent in the last ice age.

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Image courtesy NASA.

There is no calving (iceberg loss into oceans and lakes) at Mauna Kea, so the loss of glacial ice would be by melting and sublimation (or transfer directly from solid ice to gaseous water vapor). This diagram might get you thinking about the processes of warming up the glacier by solar radiation, and then the movement of long-wave infrared radiation back and forth between the atmosphere and the glacier. Also, with warm air, the sensible heat flux could also melt the ice.

The following diagrams should be a review of what you learned about glaciers in your physical geography lecture and readings. They serve to emphasize the importance of the study of the elevation of the equilibrium line as an indicator of climatic change that leads to glacial growth and ablation.

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https://www.americanscientist.org/sites/americanscientist.org/files/20085291216246708-2007-07MoteF2.jpg

https://www2.bc.edu/kenneth-galli/anatomyofglacierthumb2.jpg

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The present-day ELA at the Big Island is about 4715 meters or about 15,470 feet. The elevations of Mauna Kea (4207 m) and Mauna Loa (4169 m) are far below the modern ELA. However, there exists very clear evidence of glacial deposits. This screenshot from Google Earth shows the whitish color of glacial deposits from the last glacial period called Makanaka till (till means glacial deposit). The glaciation before the Makanaka deposited more extensive deposits at further elevations, and this has been named Waihu.

Google Earth Image

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A direct overhead view from the International Space Station of the top of Mauna Kea shows the same thing, but only over the entirety of the top of the mountain. So you can see the same locations, Makanaka and Waihu have been placed in the same locations as the Google Earth image above.

NASA Image

The reason for the light color is an accumulation of a natural rock coating called silica glaze. Silica glaze coats all of the rocks in Hawaii, and it even changes the color of fresh lava flows turning them brown. Even a coating as thin as your hair (lower left) turns a black lava flow light brown. On top of Mauna Kea, it turns the glacial boulders whitish.

Images from Ron Dorn and NASA

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A journal article about how silica glaze forms (in case you are interested, you don’t need to know this information) can be found here: http://www.public.asu.edu/~atrid/Langworthy_ESPL_2010.pdf

A project funded by the National Geographic Society, led by Dr. Fred Phillips and Dr. Ron Dorn used different dating methods to examine the ages of glacial deposits of the last three glacial periods. The very oldest, preserved in only a few places, is the Pohakaloa between 135,000 and 163,000 years ago. The Waihu glacial deposits are between 60,000 and 70,000 years old. The Makana glacial deposits are the best preserved, and glaciers were on top of Mauna Kea between 40,000 and 13,000 years ago. The maximum extent of the Makanaka was reached about 20,000 years ago. This graphic was from their article in National Geographic Research and Exploration journal.

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What you will do in this lab is to learn about how ancient glaciations are studied. You will learn a bit about the dating of glacial deposits, estimate the ELA of the Makanaka glaciation, and predict whether or not Mauna Kea will be glaciated again. You will use visual clues to estimate the terminus (variety of lowest elevations) of the Makanaka glacier at its maximum extent, and the use the half-way point between these and the summit. Then, you will account for the depression of the crust over the last 20,000 years and add that to your ELA. Lastly, you’ll determine the ELA drop 20,000 years ago.

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DETAILS ON DOING THE LAB

Part 1: Making basic observations related to the volcanoes of the Big Island

WARNING: These questions are intended to be on the easy side, and you can probably get away with doing them not in the geovisualization. That would be a BIG MISTAKE. The idea is for you to get used to the geovisualization (fast travel, moving camera angle above for a bigger view, etc…) with easier questions. You will make it difficult for yourself later on if you skip this orientation.

Question 1: Three of the big five volcanoes on the Big Island of Hawai’i have generated historic lava flows. This question asks you to match a historic lava flow to the volcano. You are given a location at the lower end of the lava flow and in the geovisualization, walk up to its source and figure out the volcano it came from.

Yes. This is an easy question. Yes, you could determine the origin outside of the geovisualization. But you should not. One of the purposes of this question is to get you used to the game, including moving and seeing the position of the avatar in the inset map to help locate the volcano.

These are the locations in order of latitudeLocation: 19.3422, -155.8821Location: 19.4204, -155.2583Location: 19.8482, -155.9460

INSTRUCTIONS: Use Fast Travel in the game environment to travel to the locations. Then, walk (or hop) your avatar up to the top of the volcano to determine the flow’s source.

Question 2: The five big volcanoes of the island of Hawai’i have very different characteristics at their summit. Visit the summits of these volcanoes in the geovisualization, have your avatar walk around and match the summit location to the characteristics that you see. Again, the hope is that this question is not difficult. Again, the reason for the relative ease is to allow you time to get used to Fast Travel and moveing around in the game, learning to move the camera angle back and above the rabbit (using your mouse or game controller) to look around at a broader view. Here are the locations:19.4055, -155.284019.4780, -155.588519.6890, -155.8648

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19.8209, -155.475020.0866, -155.7175

These are the descriptions of the summits for matching sorted by alphabetical order

This summit has a few cinder cones to the north, but there’s no clear evidence of volcanic activity at the summit. Also, the summit is not very steep. Its more of a ridge that extends off to the northwest.

This summit is occupied by a large caldera. Multiple historic basalt flows have emerged from vents to begin to fill in the caldera. Like other large calderas, it developed when the earth collapses into a magma chamber void that has emptied out. This caldera can be distinguished from the other caldera in that it exists atop the plateau of a still-building shield volcano.

This summit is occupied by a large caldera. Multiple historic basalt flows have periodically flowed out into the caldera, that sometimes collapses when the magma chamber underneath empties out. This caldera can be distinguished from the other one in that it rests on top of a very high shield volcano.

This summit is occupied by a mix of cinder cones and glacial deposits. There’s no evidence of lava flows at this summit, which has the steepest slopes of an of big volcanoes.

This summit is occupied by a mix of volcanic craters, cinder cones and lava flows. Another characteristic of this summit is that it is steeper than the volcanoes topped by calderas.

Question 3. What distinguishes the appearance of lava flows as they age over time? That is the general idea of this question.

BACKGROUND INFORMATION: Before you can begin to assess this question, first familiarize yourself with the different ages of lava flows of the Hualalai volcano – at least in a very general way. The U.S. Geological Survey has done extensive work trying to understand the ages of these lava flows through radiocarbon dating of charcoal dug out from underneath lava flows. In the map below, you can see the general pattern of ages by color grouping.

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Lava flows on the rainforest side of the Big Island change at a very different rate. Within 400 years, they can get completely covered by a rainforest. In contrast, the lava flows on the desert side of Hualalai Volcano, undergo a color change from historic to 5000 years old because of the the accumulation of the rock coating known as silica glaze. Silica glaze will turn a lava flow that is normally dark black (basalt) into a light brown color in what you will see on the Landsat image draped on the topography in the geovisualization game.

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These are electron microscope images of silica glaze on older lava flow sufaces (top row) and more recent surfaces (bottom row) on the Big Island. The scale bars are in micrometers. The gray material is the silica glaze, and the brighter material underneath is the basalt rock. Silica glaze does get thicker over time and also it spreads over more of the basalt surface and lightens the appearance. It’s the main reason why you can see ages of lava flows visually in the geovisualization.

THE QUESTION: You are given the following locations to visit via Fast Travel in the geovisualization. The locations have a similar microclimate in terms of the annual precipitation received (very low). They are only different in their age. Four different locations have lava flow ages that are historic (19th century), between 1.5 and 3.0 thousands of years (ka), between 3-5 ka, and between 5-10 ka. Go to these locations in the geovisualization – and simply rank them from darkest to lighest in appearance. Then, with that ranking, you will be able to the matching question – that has you match the coordinates to the age grouping.

19.8454-155.9609

19.7816-156.0273

19.8486 -155.9453

19.7534-156.0092

Question 3. Match the location to the age range of the lava flow, ranking them in order from darkest (youngest) to lightest (oldest) apperance in the geovisualization.

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Question 4. Rank the volcanic hazard of the three different areas of Mauna Loa’s northeast rift zone from most to least hazardous.

Volcanoes in the shield-building phase like Mauna Loa and Kilauea are characterized by rift zones, or places where there’s extension allowing a lot of lava to reach the rift and flow downhill. The shield volcano in a rift zone has lots of fractures where its easiest for magma to make its way to the surface. Kilauea’s southwest and east rift zones are fairly easy to access. There are roads in the national park that cross-cross the southwest rift zone, and people life along the east rift zone. However, Mauna Loa’s rift zone is much harder to access, especially on the upper elevations above 9000 feet. Thus, you can take advantage of the video game environment to explore the normally in accessible rift zone on the northeast flank.

Step 1: Go to the top of Mauna Loa ( 19.4722, -155.5921 ) and head downhill down the axis of the ridge (the northeast rift zone). Look around and get a sense for the three basic ways that the lava is flowing downhill from the rift. There’s a group of lava flows moving northeast towards Hilo. Then, there’s a group of lava flows heading southeast towards Volcano. The last grouping heads north in the direction of the saddle between Mauna Kea and Mauna Loa.

Step 2: Based on the visual impression you have of the dark black historic lava flows, what flank of this rift zone appears the most hazardous, least hazardous, and then in the middle of the hazard spectrum. Remember, volcanologists in Hawaii consider the percent cover of historic lava flows to be the primary indicator of hazard.

Yes. Slope steepness is important, but that factor in a volcanic hazard is not part of this question.

Your choices are:

southeast , northeast, north north, southeast, northeastnortheast, southeast, north There are no clear differences between the

three zones, and hence this is the best answer.

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Question 5 Determine the stage of evolution of Hawaiian volcanoes. Specifically select the best match between the volcano and its stage.

Step 1: To prepare for these questions, you should go back and review the different stages of evolution of Hawaiian volcanoes presented in the background information section of this lab. If you did not read it carefully and if not sure, then now is the time to review.

Step 2: Find Mauna Loa, Mauna Kea, Kilauea, and Kohala in the geovisualization. Go to these mountains. Look around. Look for the sorts of evidence you read about. Match what you see with the information on stages. This is a chance to free-range over a lot of territory and make observations compared to the theory presented here. [Hualalai is not part of this matching question. You will get to know that volcano much better in Part 2 of the lab, when you evaluate its volcanic hazards.]

Match these four volcanoes to the best stage.

Early shield-building stage without a distinct volcano shapeLater shield-building stage with a classic shield volcano shapePost-shield stageErosional stage

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Part 2. Volcanic Hazards. Evaluating the volcanic hazard of Hualalai Volcano to the Kailua-Kona area on the western flank of this volcano. Hualalai volcano has fairly steep slopes on its side, especially compared to Kilauea or even Mauna Loa. Also, the distance from the Hualalai summit to development along the Kona coast is not very far, especially compared to how far a lava flow would need to travel from the summit of Mauna Loa down towards development on its lower flanks. Steepness is definitely one aspect of assessing the volcanic hazard of a volcano. Another aspect of volcanic hazards is the severity of eruption. Does the volcano erupt with small cinder cones, small lava flows, medium-volume lava flows, or high volume lava flows, and in what combination of eruption severity. However, perhaps the key aspect of assessing the hazard is the age of the eruptions – focusing on its frequency. Kilauea is considered to be the most hazardous, because it has erupted most recently with the greatest frequency. The U.S. Geological Survey map below puts Hualalai volcano in the middle of the hazard range and hence is a perfect candidate for you to study in this lab. You get to evaluate the evidence for yourself and reach your own conclusion about the nature of the Hazard for the Kailua-Kona area.

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Question 6 in this part tasks you with evaluating the stage of volcanic evolution of Haualalai volcano. Question 7 has you evaluate whether a person could outrun a Hualalai lava flow moving down the steep western flank of the volcano towards Kailua-Kona. Question 8 has you analyze the ages of every lava flow on Haulalai volcano that has an age (either historic or radiocarbon). You decide if eruptions are becoming more likely, less likely, or staying the same level of likelihood over time.

Question 6: What stage of volcanic evolution is Hualalai in right now, based on your observations in the geovisualization? Select the best answer.

Shield stage In a transition between the shield-building stage and the post-shield stage

Post-shield stage In a transition between the post-shield stage and the eroding stage

Question 7. Hawaiian lava flows can move as fast as 6 miles per hour (the 1950 Mauna Loa lava flow), and this was because it moved down a steep slope. However, once the 1950 lava flow path was established, it started to flow much faster down established channels and flowed up to speeds of 60 miles per hour. Thus, this brings up this question.

Can a person outrun a Hualalai lava flow if you are out of shape and can only walk 16 kilometers per hour (3.73 miles per hour) and a wide lava flow (too wide to head to the side) is heading towards you at 28 km/hour (17.4 mph)? or, how long will it be before the lava flow overtakes this person?

Assume that the person has a 2 kilometer head start when s/he gets notice that the lava is heading towards them.

Select the answer that is closest to what you calculate.

The potential answers are:5 minutes 10 minutes15 minutes 20 minutes

INSTRUCTIONS:

You have different ways to solve this question. You can do this incrementally, step-by-step (perhaps also using excel) You can also use algebra.

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BACKGROUND AND SAMPLE PROBLEM USING THE INCREMENTAL APPROACH

The U.S. Geological Survey produced this map showing research on volumes of lava produced per day (in millions of cubic meters) and how much time it took different flows to each the coast. This is only for the Mauna Loa volcano.

https://volcanoes.usgs.gov/observatories/hvo/hawaii_lava_flows.html

The speed (and hence travel time) depends on a lot of factors, including the eruption rate (how fast is the lava pouring out), the slope steepness, whether the flow is ‘a’a or pahoehoe, and the sorts of topography that its flowing over. As learned in Stage A, the fastest flow known moved at about 6 miles per hour for a 1950 Mauna Loa flow when it was first advancing – or the speed of a slow jogger. Then, the lava sped up once its course was established to as fast as 60 mph.

There’s a “fun” algebra exercise of whether or not you can outrun a Hawaiian lava flow. The answer depends on how fast the flow is moving and how fast you assume a person can move.

INCREMENTAL APPROACH:

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For example, if you use the 60 mph velocity of the flow (60 mph is the same as 97 kilometers per hour, and that’s the same as 1.6 km per minute) and 11.2 mph for a human who is running (that’s 18 kph or 0.3 km/minute), then the answer depends on the starting distance. In this scenario, just take it bit by bit, minute by minute, and you’ll discover that the human will die at just after 1.5 minutes if it has a 2 km headstart.

Think about it in terms of minute and half-minute increments.In 1 minute, the human will have traveled 0.3 km or reached 2.3 km away from

the lava’s start. However, the lava will have traveled 1.6 km.In 2 minutes, the human will have traveled 0.6 km or reached 2.6 km away from

the lava’s start. However, the lava will have traveled 2.3 km. OOPS! You now figured out that the answer has to be between 1 and 2 minutes,

so try a half minute.In 1.5 minutes, the human will have traveled 0.45 km and reached 2.45 km away

from the lava’s starting position. However, the lava will have traveled 1.6 km in the first minute and 0.8 in the second halfminute or a total of 2.4 km. At the 1.5 minute mark, the human can feel the heat just 50 meters (or 54 yards) away. Doomed.

ALGEBRA APPROACH: The algebra approach is shown on this website:https://mathspig.wordpress.com/2014/11/07/volcano-survivor-2-mauna-loa-volcano-hawaii-1950/

You can take this graphing strategy, but using the information in this question.

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Or you can take this simultaneous equation strategy:

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Question 8. Evaluate the data for the age of lava flows on Hualalai. The data you will gather and analyze is a listing of every known age for different lava flows of Hualalai, ranging from historic to over 10,000 years old. These data were gathered by scientists of the U.S. Geological Survey through a lot of difficult field work, digging at the margins of lava flows and looking for charcoal (burned plants) for radiocarbon dating. You will make a histogram of these lava flow ages and decide whether you think the frequency of volcanic eruptions is speeding up (becoming more hazardous), slowing down (becoming less hazardous), or staying about the same in the last 15,000 years. You will compile the number of lava flow ages in the following age categories:

Less than 1000 yearsBetween 1000 and 3000Between 3100 and 5000Between 5100 and 10,000Older than 10,000

Step 1: Download from Canvas the HualalaiRadiocarbon.kml file. This file can be found in the instructions to the quiz. It is a resourcebext to this PDF file.

Step 2: Within the geovisualization Fast Travel menu, simply click on the Load KML button (look at the upper screenshot to the left). Find the kml file (putting it on your desktop is the easiest location), and the Fast Travel menu will turn to all of the radiocarbon ages.

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Step 3. Visit the different radiocarbon sites. You do not have to visit them all. Just visit a random selection of about 10 of them. Take screenshots for your use in writing the paragraph for this question.

Step 4. Write down ALL OF THE RADIOCARBON AGES and count how many there are in each of the 5 age categories. Then, make a histogram of all of the Hualalai radiocarbon ages. You can make the histogram by hand or you can use a program like excel … and there are lots of tutorials on how to do this… for example in this Google search link.https://www.google.com/search?q=how+to+make+a+histogram+in+excel

Then, answer this question 8 (it will be an essay question format in canvas):

For 10 pointsWrite a paragraph telling your observations regarding the visual appearance of how the lava flows change in appearance (in the Landsat Composite layer) over time and also how their appearance is influenced by precipitation (using the precipitation layer in the game). In the words of this paragraph, use specific examples from the game, providing the radiocarbon age and the latitude/longitude coordinates in the examples. A full point answer will include at least four examples that provide a range of ages and a range of climates (from low to high precipitation amounts).

For 10 points Then, upload your histogram in the canvas essay.

For 5 points:Lastly, write a paragraph interpreting the histogram. Specifically, in this second paragraph – answer the question of whether you think the frequency of volcanic eruptions is staying the same over time, increasing, or decreasing. You should also explain your confidence (or lack of confidence) in your assessment.

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Part 3. Science & Society Essay – QUESTION 9

In this essay, you are an independent consultant, hired by a wealthy investor who is wanting to know whether the Kailua-Kona area will be too hazardous to create a major real estate development. The investor is thinking of spending over a billion dollars in this development and the person wants an independent assessment from you. The scoring for this essay is simple. You are expected to write at least three “beefy” paragraphs that have a minimum amount of word fluff. Stuff the paragraphs with information GATHERED DOING THIS LAB. Do not try to find material to plagiarize from the internet. It is not worth the risk. If you plagiarize material, you will automatically receive a ZERO for this ENTIRE LAB. Plus, when we read essays, we are focusing on how you analyze the material that you learned in doing this lab – not in doing outside readings. Your paragraphs should accomplish all of the following for full credit: (i) explain the stage of Hualalai and what that stage means for your hazard analysis; (ii) explain your observations on the frequency of lava flows over time; (iii) explain your thinking about whether the investor would be able to remove mobile investment resources (e.g. vehicles, supplies) before a lava flow reached the property, thinking about the speed of lava flows and the steepness of the volcano; (iv) make an overall recommendation on whether there is a risk to the development in the next 100 years – the anticipated life expectancy of the development.

ADDITIONAL INFORMATION The Big Island of Hawaii is divided up into different real estate districts. The northern part of the Kona District, including Kahaluu-Keauhou, Kaillua-Kona and Waikoloa Village, are all under the steep western flank of Hualalai Volcano.

Real Estate Districts GoogleEarth views of Development on Hualalai, Volcano

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Digital portrayal of topography, showing steep western slopes.

Ground photograph of Hualalai from the airport, showing steep western slopes.

Hualalai Volcano does not get the publicity of some of the other Hawaiian volcanoes, such as Kilauea and Mauna Loa, but it has seen eruptions in the last couple hundred years. Hualalai is the third youngest of the volcanoes of the Big Island. Its steep slopes towers above above Kailua-Kona. The most recent eruptions of Hualalai Volcano occurred in 1800-1801 and covered an area shown on the map below.

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Artistic portrayal of how Mauna Kea might have looked at the last glacial maxima, when the Makanaka glacial till would have started to be deposited. Art by ASU student Alexis Ruiz using Google Earth imagery.

Part 4: Will Mauna Kea ever be glaciated again?

There part of the lab has three questions that are designed for you to figure out if the next glaciation of our planet will put another ice cap on top of a Hawaiian volcano.

Question 10: How far down in elevation did the lobes of the Mauna Kea’s glacier (Makanaka age) extend at the end of the last ice age?

BACKGROUND: Starting at the top of Mauna Kea (19.8206, -155.4681), there are three main lobes to the ancient Mauna Kea glaciers, like a 3-leaf clover: to the north, to the southeast, and to the southwest. If you jump down to the elevation around 3300-3400 meters, and pull the camera angle back away from the rabbit (using your mouse or game controller) – you will see a change in color. The glacial till boulders are coated with silica glaze, giving a much lighter color to the area that was covered by ice. You can see

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this lighter coloration in the space station and other imagery in the background section of the lab

Step 1: In the game, visit the following six places via Fast Travel or just running around. Write down the elevation you see in the game. [Do not use Google Earth. Google Earth has a smoothing algorithm that uses the same elevation data as the game, but it smooths it between 30 m grid cells.]

Latitude Longitude Elevation in the game

19.8207 -155.418419.8629 -155.441719.8512 -155.504519.7977 -155.510419.7756 -155.473319.7978 -155.4184

Step 2: Calculate an average (mean) of these elevations.

Step 3. Select the closest answer when you answer the canvas quiz question.

Question 11: What was the equilibrium line altitude of Mauna Kea in the last glaciation of the mountain, called the Makanaka glaciation?

Reminder: Above the ELA, snow accumulates and ice builds up. This ice pushes out and downhill on Mauna Kea into the elevation where the ice melts and also

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sublimates (ice directly into water vapor. To determine the ELA on Mauna Kea, you find the half-way point from the top of the glacier (estimated by the top elevation of Mauna Kea) and the lowest point on the glacier. If you are unfamiliar with the idea of equilibrium line altitude of glaciers, then you need to go back to the part of this lab that provides this background. Just scroll back in this PDF file and read that material about glacier ELAs. Then, continue reading this section. There are lots of different ways that geomorphologists use to estimate the ELA of a past glacier. Some involve modeling the ice cap. Some use the elevation of glacial cirques. Others use the maximum altitude of a lateral moraine (that deposits only below the ELA). However, for tropical ice caps like Mauna Kea, there is a simpler way to approximate the ELA.

Step 1: Measure the top of Mauna Kea in the game

Step 2: Using your answer to question 10, calculate the half-way point. All you do is add the two numbers together (average elevation of the maximum extent and the summit), and then divide by 2.

Step 3: Next, you have to account for the isostatic depression of Mauna Kea. The GPH 111 lecture class covered the concept that as the Hawaiian volcanoes kept growing, magma from the mantle was deposited on top of ocean crust. This heavy load has led to the gradual lowering of the ocean crust over time. The diagram below from the U.S. Geological Survey was made to explain how evidence of past sea levels (called strandlines) have been dragged down by this isostatic depression. The same is true for the glacial deposits of Mauna Kea.

Specifically, use a rate of lowering of 2.5 meters per thousand years, and the age of the last Makanaka Ice Cap of 20 thousand years before the present. Yes. Just multiply 25 m/ka by 20 ka, and the result is 50 m.

Step 4: Add this 50 m of isostatic lowering to what you calculated in step 3, and that is your answer.

These are your choices in canvas in numerical order: 3325 m, 3782 m, 3822 m, 4237 m

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QUESTIONS 12 and 13 ask the question of whether there will ever be another situation of ice on fire, or will there ever be another glacial ice cap on Mauna Kea?

Question 12. When will the next big glacial event take place? and what will be the elevation of Mauna Kea at this time?

To answer this question, you need to read a graph carefully from research modeling changes in Earth’s orbit by Professors Randall Cerveny (ASU) and John Shaffer (Maricopa Community Colleges). You have to read this graph carefully. There is a lot going on in explaining past glacial cycles and past glacial collapses (called terminations).

Step 1: Look at the top of the graph for when glacial maxima times occurred (the down arrows). Maxima occurred when the sun’s noontime insolation (radiation) was at is maximum in winter at the latitude where moisture would be evaporated (20˚N) for snowstorms, and was at its minimum in summer (37˚N) so as to not melt the glaciers. Thus, when the redlines are high and the blacklines are low, glaciers advanced.

Step 2: The end of an ice age (a termination) takes place when the peaks of solar radiation align in summer and in winter. These are the up arrows called glacial terminations.

Step 3: Look at the time scale in thousands of years with 0 being the present. You’ll notice two down arrows for the next two predicted glacial maxima. Look carefully at the time scale.

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Step 4: Starting with the present elevation at the top of Mauna Kea in the game, determine the rate of subsidence of Mauna Kea of 2.5 m per thousand years. Just multiple 2.5 m times the prediction for the next glacial maxima. That is the amount that Mauna Kea will probably be lowered by the time the next glacial maximum takes place.

Step 5. Multiply the rate of subsidence by when the next global glacial event will occur. This will give you the amount that Mauna Kea will have lowered by that time in the future. So just subtract this amount of subsidence from the elevation of Mauna Kea in the video game. That is your answer.

Your choices are3992 m at 10,000 years in the future 3992 m at 60,000 years in the future4188 at 10,000 years in the future 4202 m at 60,000 years in the future

Question 13. Will there ever be another ice cap on Mauna Kea in the future?

Artistic portrayal of the Makanaka-age glacier on Hawai’i’ as it advanced towards its maximum extent — all on top of the Mauna Kea volcano. Art work by ASU student Alexis Ruiz, using Google Earth imagery.

GUIDANCE: You know the ELA that you calculated for the last glaciation in the answer to question 11. You know how high the top of Mauna Kea will be when the next ice age is supposed to occur. Thus, the answer should be pretty simple. Will the summit of Mauna Kea still be above the equilibrium line altitude in the next glaciation? Yes, this assumes that the conditions of the next glaciation will produce a similar ELA to the last glacial event.

You will have three choices:

No ----- or Yes ----- or

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The top of Mauna Kea is very close to the Makanaka ELA (within a few tens of meters), and given the big uncertainties involved in all of these calculations, the best answer is that more detailed research and analysis will be needed to figure this out. Basically, its too close to call in this introductory laboratory exercise.

Part 5: How fast does it take to erode a river valley in Hawai’i?

BACKGROUND: The river valleys that erode into tropical island shield volcanoes are spectacularly deep and steep-sided. Their development requires torrential rainfall that causes landsliding of the valley sides (ripping out tropical rainforest trees and plummeting them down into the canyon bottom). The rainfall also results in big flood events that can move even giant boulders and these rainforest trees. This process takes time and heavy rainfall, and its characteristics are diagramed below in an image crafted by T.M. Oberlander of Cal Berkeley.

For this last part of the lab, you will be using the volcano of Kohala, because it stopped being in the shield stage about a million years ago and its volcanism almost all stopped then. Thus, in 1 million years, it has developed these river valleys on the side facing the trade winds that receive a lot of rainfall.

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However, on the older side, the western slope of Kohala, there is a rainshadow that keeps precipitation down to much lower level. The rainshadow side has not seen the development of these deep river valleys, but very shallow ones. Thus, with the age of when Kohala stopped its lava flows known at 1 million years, you are able to estimate the rate of valley creation on the windward rainy and the leeward rainshadow sides of this volcano. All you need to do is estimate the VOLUME of the lava that has eroded away. The names of the two rivers you will explore are indicated in geovisualization screenshots below

Honokoa Gulch Honokane Nui

For Fast Travel to Honokane Nui valley jump to (20.1887, -155.7229)Or Fast Travel to Honokoa Gulch jump to (20.0524, -155.8386)

Volume is a calculation that most students learned in elementary school or middle school. It’s the length times the width times the depth. The length of the very deep section (that you will be measuring) of the Honokane Nui valley is 10,000 meters long. The valley ends at a cliff face, and it will grow “backwards” into Kohala’s shield surface over time. But right now, the valley you are measuring is just the very deep part. The length of the Honokoa Gulch extends all the way up to the top of Kohala, and that is 13,000 meters long. So now, all you need to do is estimate the average depth and average width of these very different river valleys. Once you have this estimate, you can calculate and estimate of the volume. The questions you will be answering ask you to then estimate the RATE OF EROSION of each of these river valleys in cubic meters per year. Thus, the calculation is volume (cubic meters) divided by the number of years (a million)

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Question 14: What is the rate of erosion of the Honokoa Gulch in cubic meters per year? Your choices will be: 40 m3/year, 4000 m3/year, 40,000 m3/year, and 40 million m3/year.Question 15: What is the rate of erosion of the Honokane Nui valley in cubic meters per year? Your choices will be 460, 4600, 55,000 or 4.6 million m3/yearQuestion 16: How much faster is the Honokane Nui valley eroding compared to Honokoa Gulch? Your choices will be that Honokane Nui valley is eroding about 15, 55, 85 or 115 times faster than Honokoa Gulch.

HOW TO ESTIMATE VALLETY DEPTH:You will need to make this estimate at the following elevations as you walk up the valley.The elevation you will see could be a range, depending on where you stand, but try to stand in a place that gives you an elevation somewhere in the range you see. Elevation floor of Honokane Nui valley (meters)

Elevation above the valley

Depth Width

3590-110 215278-333345-368500-515

AVERAGEIt is okay if you cannot get the rabbit to the exact valley bottom elevation. Even a difference of 10 m won’t make a difference in you getting the correct answer.

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To estimate the depth, just go to the elevation in the chart above in the Honokane Nui valley, and then write down the elevation at the top. Below you can see a screenshot above of the rabbit at 90-110 m in the Honokane Nui valley bottom. Then, you can hop to the top (or Fast Travel being careful), the elevation is about 455. Thus, the depth at this place is about 350 m deep. PRECISION IS NO IMPORTANT. JUST DO YOUR BEST. The range of answers at the end does not require super high precision on elevation measurements. The width estimate requires that you be careful with your depth measurement, because you will DOUBLE your depth measurement as an approximation of the width. Let’s assume for the moment that the AVERAGE of these five cross-sections you are measuring is 2000 m wide, and let’s assume that the average depth is 1000 m deep, and you know the length is 10,000 meters. When you multiply the above rounded and not correct numbers together, you will come up with a volume of 20,000,000,000 m3. Check your math quickly. Remember when you multiple values like these, just count the number of zeroes (3+3+4) to make sure that you didn’t mess up.

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Now, divide 10 trillion cubic meters by a million. That is a rate 20,000 cubic meters per year. If you can picture a cube of basalt lava 43 m by 43 m by 43 m, which is the same as 140 ft x 140 ft x 140 ft. THIS IS NOT THE ANSWER TO QUESTION 15!!! Remember, this example using width and depth values that are not correct. But this example will help you see if your calculations are way far off.

HOW DO YOU DO THIS FOR THE Honokoa Gulch? You can use this table to fill it inElevation floor of Honokoa Gulch (meters)

Elevation above the Gulch

Depth Width

3590-110 215278-333345-368500-515

AVERAGE

Start by looking an example location along this small river valley on the next page. That is what a river valley looks like in the game. Just like in a contour map, the river is identified by the “V” shape pointing up Kohala mountain. Notice that right at this V notch, the avatar’s elevation is 455 m. By hopping up to the top, the elevation reads 515. Thus, the river valley’s depth at this spot is about 60 m deep. To estimate the width, use the same value as the depth, and in this cross-section it would be 60 m wide. So let’s assume that the average of the 5 depths you measure at 105 m 200 m, 315 m, 350 m, and 500 m is one hundred meters deep. Thus, the volume calculation would be 100 m (depth x 100 m (width) x 13,000 m (length). Again, count the zeroes to make sure that you didn’t do a typo on your calculator. 130,000,000 m3. Then, if you divide 130 million cubic meters by a million years, that is 130 cubic meters per year for an erosion rate. THIS WILL NOT BE THE CORRECT ANSWER, BECAUSE THE DEPTH IS WRONG. However, it will be in the ballpark. By the way, the cube root of 130 is about 5, and so picture a cube 5 m x 5 m x 5 m (or 16x16x16 feet).

Question 16: How much faster is the Honokane Nui valley eroding compared to Honokoa Gulch? Just divide your answer for question 14 by question 15.

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So in the example above that would be 20,000 m3/year divided by 130 m3/year or about 150 times faster (rounded from 154). Again, this example is just for illustration purposes. It will not be the right answer.

Question 17: Compare the answer to question 16 (how much times faster is Honokane Nui valley eroding compared to Honokoa Gulch) to the annual rainfall received in their drainage basins. Step 1: You can get a good estimate of average annual rainfall in these drainage basins by fast traveling to these coordinates and changing to the isohyet display.

Coordinates Mean Annual Precipitation at the coordinates

Honokane Nui valley: 20.1190 -155.7132Honokoa Gulch: 20.0070 -155.8029

Step 2: Then, divide these valleys to figure out how much more annual precipitation is received in the Honokane Nui valley. Step 3: Compare your answer to question 16 to the answer of Step 2. Look at the numbers. You will divide the larger by the smaller number, and you’ll have your answer.

HINT: The answer may surprise you, because the enhancement in erosion is not reflected in the enhancement in precipitation. You might have expected that, for example, 2 times more rainfall would produce 2 times more erosion. This is not always the case in geomorphology! In fact, it is rarely the case. The reason is that the processes that erode these river valleys are very different. Jump to the start of Part 5, and remember how valleys like Honokane Nui erode: by landsliding and massive flooding during extreme rain events. Its these extreme rainstorms that do the vast majority of the erosion, and small daily rain events do very little.

These are your choicesThe Honokane Nui valley is eroding about 15 times faster than Honokoa Gulch. However, only about 10 times the amount of rainfall (5000 mm vs. 500 mm) falls over Honokane Nui valley (compared to over Honokoa Gulch)

While Honokane Nui valley is eroding about 115 times faster than Honokoa Gulch. However, only about 14 times the amount of rainfall falls over Honokane Nui (~4200 mm) valley compared to over Honokoa Gulch (about 300 mm)

The Honokane Nui valley is eroding about 20 times faster than Honokoa Gulch. However, only about10 times the amount of rainfall (5000 mm vs. 500 mm) falls over Honokane Nui valley (compared to

The Honokane Nui valley is eroding about 85 times faster than Honokoa Gulch. However, only about 8 times the amount of rainfall (4000 mm vs. 500 mm) falls over Honokane Nui valley (compared to over

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over Honokoa Gulch). Honokoa Gulch)

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