Pacific Northwest Seminar Trip

Columbia River Flood Basalts (17 - 6 Ma)

17 million years ago large basalt fissures, similar to that of Hawai'i and Iceland, erupted at the Idaho, Oregon, and Washington border releasing 174,000 cubic kilometers (42,000 cubic miles) of lava. This lava covered 164,000 square kilometers of eastern Washington and Oregon and parts of the western panhandle of Idaho and is known as a large igneous province (LIP). These eruptions occurred for 9 million years with decreasing volumes.

Grande Ronde was the first and largest of all the lava flows that erupted and accounts for 90% of all erupted basalt. The lava flows traveled west across Oregon and Washington until they reached the Cascade mountains where they were diverted to the Columbia River. There they followed the path of the river to the Pacific Ocean.

Several larger LIPs have occurred in Earth's history, Permian-Triassic Siberian Traps which nearly whipped out all life on Earth and the Cretaceous-Tertiary Deccan Traps in India that may have helped kill the dinosaurs. However, scientists are unsure on what causes these large out pouring of basalts across time and space. Some believe that the Columbia River Flood Basalts are the result of magmatism from the upwelling mantle plume that created the Yellowstone Hotspot 17 million years ago.

In satellite view one can see the relatively flat terrain between the northern Rockies in Idaho and the Cascades. Following the end of the ice age, the basalts were covered by wind-blown dust several meters thick in some locations. This area is known as the Palouse and is the largest producer of wheat in the United States.

Pictures by: (1) Sarah Godsey, Idaho State University (2) Jennifer Kasbohm, Princeton University

Mazama Eruption ( ~8000 years ago)

Formation:

• Mount Mazama, a large composite volcano formed over half a million years, features U-shaped valleys carved by glaciers and consists of alternating layers of lava and pyroclastic materials. About 30,000 years ago, it began producing explosive eruptions and thick rhyodacite flows. Its last major eruption, nearly 8,000 years ago, was the largest in the Cascades in the past million years. Composed of basaltic andesite, andesite, dacite, and rhyodacite, Mount Mazama is currently dormant but may erupt again.

Landmarks:  (USGS)

• Mount Scott, formed by the earliest explosions

• Phantom Ships, 400,000 years old, oldest rocks exposed above lake level in the caldera

• Sun Notch & Kerr Notch are preserved glacial valleys that weren't later filled in by lava

• 200 years prior to the caldera collapse, an explosive eruption deposited the white layer of pumice and ash beneath Llao rock

• The orange Pumice Castle was deposited by the older smaller eruptions while the thick  layer of pumice and ash on the caldera rim was from eruptions 8,000 years ago.

The Collapse: (USGS)

• Around 8,000 years ago, a massive eruption from a vent on the northeast side of Mount Mazama sent a pumice and ash column 30 miles high, spreading across the Pacific Northwest and southern Canada. The rapid ejection of magma caused the chamber to collapse, forming a 5-mile-wide, 1-mile-deep caldera. As rain and snowmelt filled the caldera, new vents created volcanic features like Wizard Island and the submerged Merriam Cone.

Snow Hydrology

Snow hydrology is a subset of hydrology that focuses on the composition, dispersion, and movement of snow and ice. Snow hydrology is especially important in semi-arid environments with few other sources of water. Many areas in the west depend on snowmelt as freshwater sources for agriculture and urban use. 

In the crater lake region, snow hydrology plays an important role in the ecosystem balance and landscape formation. Snow pack provides insulation that allows plants and animals to survive through the winter. Some organisms, such as ice worms and green algae, depend on the ice and snow to live. 

Crater Lake has consistent water levels because of the balance between snow, rain, evaporation, and the water table levels. Lake levels fluctuate ~4 feet seasonally, with higher lake levels in the summer due to snow melt and lower lake levels in the winter. On average, the Crater Lake area receives ~43.5 ft of snow which often results in road closures from November to May. Rainfall in these months (rain-on snow) can lead to avalanches due to increased weight if the rain freezes or melting the snow if it is warm. Snowfall records for the past ~100 years have shown that snowfall has been decreasing and expected to continue to decrease.

Pictures by: (1) Ryan Nielsen and (2) Kestrel Hulet

The location was incredibly accessible, allowing you to drive right up to the crater overlook and park conveniently. The views are absolutely breathtaking, showcasing all the features of the lake. Overall, I would rate this experience a 5 out of 5!

Pinnacles and Fossil Fumaroles (7.7 ka)

Pinnacles, or spires, are erosional features that create individual columns completely separated from surrounding landforms. They are often more erosion resistant, so as the surrounding land erodes away they are left standing.

Fossil Fumarole form when a sheet of pumice is cooling and pushes hot, mineral rich gasses up through cracks in the ground (called a fumarole). There was then a pyroclastic flow that filled in the cracks, so when the hot gasses moved through they welded all of the material together. Then, once the setting has changed and the ground eroded away these welded minerals resist erosion and stick up out of the ground. These cone shaped spires can be seen at the Pinnacles Overlook Southeast of Crater Lake.

Pinnacles are different from hoodoos in that hoodoos are generally formed in a sedimentary setting, where an erosion resistant rock sits atop less resistant sediment. This cap rock protects the lower sediment as the rest of the slope erodes away, preserving a tower sticking out of the ground. These are what can be seen in Bryce Canyon, Utah.

The fumaroles could not be seen too well at this location, but the views are spectacular. 1/5 for fumarole observation. 5/5 for views.

Mt. Shasta (300,000 to 500,000 years ago)

Mount Shasta is the most voluminous of the Cascade volcanoes in northern California. It is a stratovolcano, composed of at least four main edifices constructed over at least 590,000 years. A large debris avalanche destroyed an older edifice which filled the Shasta River valley to the NW. 

The magmatic system has evolved for at least 590,000 years, with the current stratovolcano being built through four major cone-building episodes. These eruptions, lasting a few hundred to a few thousand years, produced lavas, dacitic domes, and pyroclastic flows extending up to 20 km (12.4 mi) from the summit.

Over the last 10,000 years, it has experienced eruptions that produced lava flows and domes on and around its flanks. One of them, Shastina, was primarily formed between 9,700 and 9,400 years ago, while the Hotlum cone, which forms the summit and the north and northwest slopes, may overlap in age with Shastina but is likely younger overall.

In the last few millennia, smaller eruptions have occurred at the summit and upper-east flank, with the most recent eruption around 3,200 years ago, producing block and ash flows on the north flank. Despite low earthquake activity and negligible ground deformation over recent decades, real-time monitoring is conducted by a network of nine GPS receivers installed between 2005 and 2007 by USGS and UNAVCO.

Pictures by: (1) Daliedmarie Delgado Maisonet and (2) Kestrel Hulet

While we couldn't see Mt. Shasta from our stop, the drive offered spectacular views of the volcano. Overall, the spot itself rated 2/5, but the views while driving earned a solid 5/5.

Climate Change in Northern California (Present)

Climate change is having a profound impact on Northern California, particularly in terms of snowpack, precipitation patterns, air temperatures, and the increasing frequency and intensity of wildfires. One of the most notable effects is the diminishing snowpack in the Sierra Nevada and other mountainous regions, including Mount Shasta. Snowpack serves as a crucial water reservoir, gradually releasing meltwater during the warmer months to supply rivers and reservoirs. However, rising winter temperatures have led to more precipitation falling as rain instead of snow, reducing the snowpack and causing earlier and faster snowmelt. This shift not only affects water availability for agriculture and urban use but also disrupts ecosystems that rely on consistent water flow from snowmelt. In Northern California, where water resources are already stretched, this reduction in snowpack could increase water shortages in the coming decades.

The changing climate has also altered precipitation patterns in Northern California, leading to more extreme weather events. While overall annual precipitation may not have drastically decreased, it has become less predictable, with more prolonged droughts punctuated by intense, heavy rainfall during storms. This combination of dry periods followed by sudden downpours can lead to flooding, soil erosion, and increased stress on the region's water management infrastructure.

Rising air temperatures have also intensified the impacts of droughts, leading to drier soils and vegetation. Warmer temperatures also create favorable conditions for wildfires, as the drying out of forests and brush increases the likelihood of fires igniting and spreading. Northern California has seen a dramatic rise in the frequency and severity of wildfires in recent years, with devastating fires threatening both natural landscapes and human communities.

We didn't have a specific stop for talking about climate change but it's an important topic to include in trip to California.

Surface Groundwater Interactions-Burney Falls (5.3 to 1.8 Ma)

Burney Falls, located in McArthur-Burney Falls Memorial State Park in Northern California, is an example of the interaction between groundwater and surface water, which is closely tied to the region’s volcanic geology.

The falls are fed by Burney Creek, but much of their year-round water supply comes from underground springs. These springs are sustained by rainwater and snowmelt that percolate through the porous volcanic rock of the Modoc Plateau. The area’s basalt rock, formed from ancient lava flows, allows water to infiltrate deep underground and store in large aquifers. As the water moves through the rock layers, it reemerges at the base of the falls, creating a constant flow of about 100 million gallons of water per day, even during periods of drought. This interaction between surface runoff and groundwater results in Burney Falls' unique appearance, where water cascades not only from the top of the falls but also from the cliff sides through numerous small outlets.

This stop was easily accessible and had beautiful views. Making it a 5 out of 5 star stop!

Mt Lassen Eruptive History

Mt Lassen is the southern most active volcano in the Cascade Volcanic Arc. In 1915, Mt Lassen had the largest volcanic eruption in the Cascades until 1980 when Mt St Helens erupted in Washington.

On May 30, 1914, ground water interacting with hot rocks causing a steam explosion that made a small crater that was then enlarged by following 180 steam explosions at he summit. These steam eruptions lasted until May 1915.

The evening of May 19, 1915 a large eruption launched hot rocks that melted snow on the summit leading to generation of mud flows called lahars to flow down the summit.

May 22, 1915 a large eruption occurred creating a large crater at the summit of Mt Lassen and launched ash and gas 30,000 ft into the atmosphere. Boulders from the eruption can be seen in the devastation parking lot at Mt Lassen National Park.

Chaos Crags (1 Ka)

Lava domes form by the effusive eruption of high-viscosity lava and are inherently unstable and prone to collapse and are thus a significant volcanic hazard. Effusive eruptions are a type of eruption in which lava steadily flows out of the volcano onto the ground. Typically, effusive eruptions consist of runny basaltic magma due to low viscosity. This is also the typical formation process for shield volcanoes. Magma that has a high viscosity typically controls explosive eruptions because the magma is silica rich. But with lava dome formation, high viscosity magma is exhorted as an effusive eruption. This process typically forms after explosive eruptions when the dissolved gas has been released. The slow ascension of viscous magma is what leads to the formation of a lava dome.

Domes are unstable features, and their collapses are grouped into two categories: active and passive. Active collapses are driven directly by lava effusion. Collapses are “pushed” by mechanisms associated with the growth of a lava dome or flow or by gas over pressurization within the lava. Because active collapses are sourced from regions of new growth of the lava, the size of the dome generally correlates with the eruption rate. Passive collapses happen when internal processes (not related to addition of dome volume) occur in situ until failure occurs. Processes include failures caused by internal dome weakening (cooling, fracturing, and/or hydrothermal alteration) until the weight of the dome exceeds its internal strength. Therefore, the size and frequency of passive collapses does not correlate with eruption rate. A small passive collapse can expose the gas-rich interior of a dome, triggering a depressurization explosion that causes a larger dome collapse. Passive collapses have one characteristic that makes them especially dangerous: unpredictability. Because passive collapses do not correlate with effusion rate they can occur with no warning.

Chaos Crags are also the youngest domes in Lassen, forming about 1000 years ago. They formed from a very silicic magma called Dacite. Viscous lava emerged from the ground, and as it cooled, the lava surface contracted, breaking and forming large debris piles adjacent to the cone. Two pyroclastic flows were emplaced (hot dry flow of volcanic rock debris propelled by gravity and lubricated by heated trapped air). After a peaceful period of about 70 years, Dome A was destroyed by a violent eruption that resulted in a pyroclastic flow (active collapse). This violent eruption was followed by the growth of 5 domes (B, C, D, E, F).

Let's say another large eruption with pyroclastic flows were to occur again. This event would be preceded by small-scale activity. Therefore, there would be enough warning to evacuate before a large-scale eruption. A more hazardous situation would involve a passive collapse. A rock fall avalanche would occur with no warning, therefore, velocity would preclude evacuation to prevent loss of life and could extend 5km east/west of the Chaos Crags.

Rating: 2/5. The pullout does not have a view of the Chaos Crags. Therefore, images of the domes were substituted in handouts for visualization.

Image credit: USGS, 2010

Hat Creek and Paradise Meadow (3 Ma)

Alpine meadows are high-altitude ecosystems found in mountainous regions. The meadows are characterized by open spaces, various grasses, and wildflowers that are adapted to cold temperatures.

Often found in alpine meadows are spring ephemerals which include plants first to emerge and bloom in the springtime. Spring ephemerals revert to dormancy in the summer and lie underground as bulbs until the following spring.

Rock and soil in this area are carved and formed by glaciers. Mountain streams that run through the meadows are crucial to biodiveristy of the ecosystem. Various species of trout and mountain lilies depend on meadow streams for survival.

Rating: 4/5. The site is a beautiful example of an alpine meadow where lots of wildlife was observed. Exploration was limited due to wetland terrain and timing was not in favor to observe the spring ephemerals.

Geothermal Activity & Geothermal Energy Potential - Lassen Sulphur Works

Formerly known as Supan's Sulphur Works until the 1950s, Lassen Sulphur Works is one of the most prominent locations to observe hydrothermal activity within Lassen Volcanic National Park. Sitting directly on the remnants of Mount Tehama's central vent, underground magma heats overlying rock and water which creates the geothermal systems seen today. Notable hydrothermal features at the Sulphur Works includes fumaroles (steam and volcanic gas vents), mud pots, boiling pools, and steaming ground. Be prepared for the smell of rotten eggs if you visit though, a very distinct product of the sulfur!

Not only is Lassen Sulphur Works great for viewing geothermal activity, but it is also a suitable place to discuss geothermal energy potential. Geothermal energy is created by using warm places near the earth's surface to warm water and create steam to turn a turbine and make electricity. A majority of northern California's electricity is generated via geothermal energy and the Sulphur Works demonstrate why geothermal energy is so prevalent in this part of the country. The ability to create clean, renewable energy 24/7 hours a day is enticing, but the high costs of development and relatively rare conditions for effective electricity creation hold geothermal energy back from becoming truly widespread.

4/5: Fun and accessible location, just be ready for the smell!

Dixie Fire - Butterfly Swimming Hole

On July 13th, 2021, a felled power line would spark a fire that would become the largest single-source wildfire in recorded California history. The Dixie Fire lasted for more than three months and was not contained until October 25th, 2021. The fire burned just shy of 1,000,000 acres of land and lead to the destruction of multiple towns such as Greenville, CA. Pyrocumulonimbus clouds, smoke, and ash could be witnessed as far away at western Colorado at the greatest extent of the fire. More than $600 million was spent in suppression efforts.

Multiple factors played a part in the severity and scale of the Dixie Fire. High temperatures mixed with low precipitation made for a brutal drought year in 2021. The lack of precipitation led to especially dry soil and vegetation, making a perfect fire-starter. Additionally, fire prevention policies had led to significant buildup of low-lying dry vegetation. Under normal conditions, low-lying vegetation would periodically burn in smaller fires and other plants accustomed to fires, such as Lodgepole Pines, would continue to grow without extreme competition for resources. This "Ecological Memory" that shapes the current ecosystem is disrupted when periodic fires do not take place. As such, the vegetation buildup led to a much larger fire than is normal, one that can even burn through Lodgepole Pines and heavily disrupt recovery of the affected ecosystems. To prevent future fires similar in scale to the Dixie fire new policies are being evaluated for regular, controlled burns to clear out low-lying vegetation.

Rating: 4/5. Fun place to swim with a swing! Not much more than a road pull-off though

Independence Lake

Pleistocene Glacial History of North Sierra Nevada

Glaciers are a slow moving mass or river of ice formed by the accumulation of snow on areas of high altitude and elevation.

Equilibrium Line Altitude (ELA) is the boundary between the accumulation and ablation zone. The accumulation zone is where more snow and ice build up then melt. The Ablation zone is where snow and ice melt faster than accumulate. The flowing ice melts faster than is delivered and disappears at the glacial toe. The ELA moves up hill if average temperatures increase or precipitation decreases, and moves down if temperatures decrease or precipitation increases.

Moraines are the material that is left behind by a moving glacier, they also serve as a boundary for the glaciers. Cirques are bowl shaped depressions that serve as the glaciers source of origin.

Pleistocene Glaciation occurred during the Pleistocene, estimated that glacial ice covered and area of 20,000 square kilometers. Glaciers during this time in the Northern Sierra Nevada's occurred above 1500 meters in elevation. Dating of certain Pleistocene glaciers is difficult due to later glacial moraines.

There are 7,040 lakes in the Sierra Nevada range most of which are glacial in origin and were dammed from landslides, fault scarps, volcanic origin, and moraines. The largest lake is Lake Tahoe which was created by melt of Pleistocene glaciers flowing west and south along with range faulting and lava flow damming.

Sagehen Creek Research Station

Critical Zone & Overview of Sagehen

Sagehen research station was founded in 1951 by A. Starker Leopold and PR Needham. Sagehen was origionally founded as a fisheries and wildlife habitat research center for UC Berkley, and UC Davis. Sagehen research station is located on the historic lands of the Washoe Tribe.

Sagehen is a unique research center due to its methodical approach to scaling observations from individual trees to entire watersheds. Another reason that Sage hen is unique is due to its roughly 70 years of documented research.

Critical Zone is a system of coupled chemical, Biological, Physical, and Geological processes operating together to support life at the earths surface. Earths surface is classified as treetop to bedrock. Critical Zone has 5 main components: Atmosphere, Vegetation, Soil, Surface Water, and Ground Water.

Sagehen is home to many sensors that are currently monitoring many different natural processes. Some of the sensors that are currently installed at Sagehen are: National Atmospheric Deposition Program (NADP), Weather Station Data, SNOTEL, Stream Flow, and Water Quality. The USGS also has a discharge gage that is measuring in cubic feet per second.

Sagehen is home to many different scientific studies, currently there are 6 studies going on at Sagehen: Plant Communication which is looking into Sagebrush Communication. Avian Productivity and Survivorship that is a continental collabrative project for bird conservation. A Lahontan Cutthroat Trout study designing fish barriers. Highway 89 Road Ecology that is radio collar monitoring deer, and 3 undercrossings. A Chickadee study that is looking at the elevation differences with Cognition and memory.

Spring Hydrology at Sagehen Field Station (1950-present CE)

Sagehen Valley is a unique geologic setting which allows for large amounts of groundwater and springs. More than 400 meters of volcaniclastic and lava flows overlie Cretaceous Granodiorite, so water can penetrate into the volcanic rocks, but is confined on the bottom by the granodiorite. This allows the water to penetrate down into the ground and slowly flow downslope as groundwater until it flows back out as a spring. Sagehen receives an average of 89 cm/yr in precipitation, 80% of which is in snow. This is beneficial for groundwater recharge, as snow melts it is much more likely to penetrate into the ground.During large rainfall events, the surface of the ground becomes saturated and creates much more runoff than snow does.

The water in the ground does not all flow in the same path. These flow paths vary in depth, residence times, and water mineral interaction. As groundwater moves through the aquifer, it takes its chemical “fingerprint” with it, so when it comes out as a spring we know when it fell from the sky. It will also interact with the minerals in the ground to help us create a story of its life from precipitation to snowpack to meltwater to groundwater to springwater all the way into the stream.

Because of different chemicals that were in the air at curtain times, we can relate the water that is coming out of springs to years in the past and date how long ago the water fell from the sky. One big marker is Chlorofluorocarbons (CFC) which you might know as what used to be in refrigerators, hairsprays, and more. CFC’s were first banned in the US in 1976 due to the evidence of eating away at our ozone layer. These are great markers because we have documentation of levels of CFCs in the atmosphere, which allows us to use them for dating very effectively. 

The general trend that we see is springs closer to the stream are older and those farther up on the hill slope are younger. This makes sense because the longer flow path and therefore residence time would be water going deeper into the subsurface and flowing out along the bottom. Conversely, the shorter flow path would stay near the surface and flow out at a spring earlier.

This stop has restricted access as a private research station, but there is a campground just outside the property. 4/5 because of access issues.

Magma Chambers

Magma chambers are spaces at depth in the Earth where hot semi-molten rock, known as magma, is stored. This magma can then either erupt from a volcano, like that of Mt St Helens or Hawai’i, or stay underground and cool off to form different rocks like granites, think the Sierra Nevadas.

Magma chambers are not the spherical shapes many people think of, but a combination of vertical and horizontal openings made by the rising magma exploiting weaknesses in the rock layers.

Some magmas come straight from the mantle and have a similar composition to the mantle. These magmas can keep rising to the surface and erupt as basalts with that similar composition like those at Craters of the Moon National Monument. However, if the magma stalls in the crust it can start to “evolve” and change chemically to another magma composition. The most basic form of this is through the formation of minerals in the magma chamber as it cools. This is similar to getting a bag of trail mix. At first you start to eat your favorite pieces first, the trail mix is still trail mix, but now a slightly different kind of trail mix, minus the m&m’s. The same thing happens as minerals crystallize within the magma chamber. The magma chamber can also change chemically by melting the surrounding crustal rock and adding it to the magma. New magma can also be added from below into the chamber. These two ways of adding new magma to the chamber is like going to the store and adding more trail mix to your original bag. It is still trail mix, just a little different.

Pictures by: (1) Jennifer Bourn

Desert Water Management (1900-Present)

Water management in the Western USA has been a hot topic for the past few decades due to the rapid growth of population centers, which are often located in places that dont contain enough natural water to sustain their populations. But these problems are nothing new, and the history of America's attempts to control and divert water in this fragile ecosystem goes back over 100 years.

Lake Lahontan, a now nonexistant lake centered around the western great basin in Nevada, was home to the Lahontan trout and ancestral native American people. The lake dried out in around 7,000 BC, but its remnants can still be seen today in the form of rare, deep lakes and salt flats. Due to the diversion of nearly all the major rivers in the area during the early 20th century, the Lahontan trout became critically endangered thanks to the destruction of their natural habitat. Efforts in the 21s century to reverse the destruction of their habitat have been slightly successful, mostly due to the reintroduction of Lahontan trout to lakes and reservoirs that they naturally existed in, but additional efforts (namely the reversal of diverted streams) are needed to help keep this fragile ecosystem from disappearing.

The Great Salt Lake, located just west of Salt Lake City, is the last remnants of Lake Bonneville, a quaternary lake centered in an endorheic basin. Although the water levels of this massive lake naturally fluctuate, the increasing amount of water diverted from this watershed for human use are creating harmful effects that continue to impact daily life for the citizens of both Salt Lake City and Utah as a whole. The lake sediment, normally contained below the water surface, are high in arsenic and other harmful elements that become airborne when left exposed to the air, which is a problem in an area known for its high winds and pollutions levels. Although the population of Salt Lake City continues to grow, finding a compromise between the amount of water than flows into the lake and the amount of water that is diverted for human use is paramount to the continued human habitation of the area.

The Colorado River is the source of lots of water disputes in the Western USA. From dams to diversions to pipelines, the continued survival of this river is absolutely essential to the longevity of both the human population and the natural ecosystem in this area. Thanks impart to the creation of the Glen Canyon and Hoover dams built on this river, this natural ecosystem's way of life has been completely changed. Changes in water temperature, sediment levels, and erosion rates have decimated native predators and flora especially, but also native prey historically found both in and around the edges of the river. As stated above, the only way forward is to consider natures needs as equally important to the human's needs when it comes to the natural resources available in this area.

There are no easy solutions to the water issues that will continue to plague the Western USA as we deal with both worsening climate change and an ever increasing population, but learning from the mistakes made in the past, both on an individual and governmental level, will help us to prevent causing additional unnecessary ecologic or hydrologic damage to the environment in our attempts to domineer mother nature and her water for our personal use.

"There is no shortage of water in the desert but exactly the right amount, a perfect ratio of water to rock, water to sand, insuring that wide free open, generous spacing among plants and animals, homes and towns and cities, which makes the arid West so different from any other part of the nation. There is no lack of water here, unless you try to establish a city where no city should be" - Edward Abbey

Rye Patch State Recreation Area is a nice place to take a break while driving though Western Nevada, but otherwise it has little to offer. 2/5

Picture by: Caden Anderson