Solve the “geological killing mystery”? New research links the Wasatchfront earthquake and the end of Lake Bonneville

Editor’s Note: This article is part of a series reviewing Utah and US history for the KSL.com History section.

SANDY – Richard Speedin views himself as a general practitioner who finds himself immersed in all sorts of topics that pique his curiosity.

The geology and canyons of southeast Salt Lake Valley can be considered two of these interests. Since Spedden was venturing into Little Cottonwood Canyon for ski trips, something disturbed him about the terrain. He felt something about it that did not add to the science he had read about it.

In March, lockdowns caused by the emerging coronavirus (Covid-19) forced people to stay indoors, the Sandy resident found himself having more time to focus on and soon began investigating what had become a passionate half-year project.

Although there was no formal education in geology – his educational background was computer science, mechanical engineering, and business – he slowly put together a theory that challenges a 130-year-old belief about how a region and the terrain of an area were formed.

Spedden’s research indicates that the terrain in southeastern Salt Lake Valley was shaped more by a tsunami caused by an earthquake rather than an earthquake itself. It is a new theory that could also rewrite the prehistoric history of Lake Bonneville and give a better understanding of how land moved in Salt Lake Valley.

Spedden is set to present his findings Friday at the American Geological Society’s annual meeting 2020 – a conference featuring some of the world’s leading geological researchers that has been held annually since 1888. In his words, the research is an answer to the “geologist” puzzle the kill “.

Creating a paradigm shift

The research focuses on the southeastern portion of Salt Lake Valley between Big Cottonwood Canyon and Little Willow Canyon. It covers the area at the edge of Cottonwood Heights, Sandy, Draper, and the Wasatch Mountains. This once-submerged area was part of the eastern edge of the large prehistoric Lake Bonneville, which covered most of what is now northern Utah.

The section is also located by the Wasatch Fault, which is a large underground fault line from central Utah north through Idaho. It is an area that has been studied many times over the course of a century.

This map shows where the Wasatch Fault and Lake Bonneville overlapped during the Pleistocene Epoch thousands of years ago. (Photo: Courtesy of Richard Speeden)

The first theories of how the region formed began in the 1890s when the eminent geologist JK Gilbert identified the Earth as an example of a topographical feature known as “capture”. According to Gilbert’s theory, the elevated water level of Lake Bonneville was subject to liquefaction during the earthquake, causing a depression along the earthquake fault line falling as a block. The most distinctive feature is at the Little Cottonwood Canyon estuary.

Map showing areas identified as “grab” near the Wasatch Fault in southeastern Salt Lake County. (Photo: Courtesy of Richard Speeden)

Gilbert’s scientific work in the area is well known, and there is a park in Sandy named after him today. Speeden said the entire area is a standard field trip for students, geologists, and hobbyists alike to study the unique terrain. Some subsequent trench studies conducted since 1890 indicated that a major earthquake occurred in the region causing outcrops and other outcrops sometime between 14,000 and 18,000 years ago during what is known as the Pleistocene Era.

Lake Bonneville’s massive flood is believed to have occurred between 14,000 and 15,000 years ago. The researchers estimated that water flowed at a rate of 15 million cubic feet per second when it occurred.

What Spedden argues from previous studies is that not all geological features of the southeastern Salt Lake County area are in line with the original theory of capture. In an interview with KSL.com, he explained that he believed a major earthquake had occurred – most likely within the timeframe presented in previous studies – and then “physics has started.”

“If there is a big earthquake under a lake, something must be submitted,” he said. “If the Wasatch Fault falls, that suddenly drops an arm of Lake Bonneville down where it should be.”

This map shows the area of ​​Salt Lake County that Richard Speedn searched for and where it relates to Lake Bonneville during the Pleistocene. (Photo: Courtesy of Richard Speeden)

He pointed to the factors of what would happen to a large lake as the earth shook underneath. It starts like a bowl of soup in your hand. If you move one side of the pot down a little, the volume of the pot rises past the uneven area before shooting back and forth and then rests.

The shock waves of what could have been the tsunami also played a role. Speeden likened the shock wave to a water-in-pipe hammer.

“I think what happened here is that there was a rise in the valley and that is what all the evidence indicates,” he said. “Think of a wave on the shore. Think of the force it exerts when that wave begins to recede. It is drawn into the sea.”

He continued, “This is what happened to all this stable, up to land masses in 10 square miles of ice, to land masses here.” “They were on a very weak layer (of sand) underneath. When that rising layer appeared, he dragged it out into the sea to a certain degree.”

The event created distinct deformations in geological features near Little Cottonwood and Bells Canyons, according to his research.

While Spedden studies the area further, he was able to correlate the Bonneville flood – given that he believed it occurred relatively close to the same time frame as the earthquake. He argued in his research that geographical evidence indicates that Lake Bonneville was at a high point within the area being reviewed at a time when an “unusual” earthquake / tsunami would have occurred before it experienced a major drop in the water level.

This could mean that the platform was actually a rift, and that other land features in the area were a result of the sudden drop in the water level. Landmarks in northern Utah and southern Idaho indicate the potential impact of “concentrated” energy.

“The inescapable conclusion is that right after (the prehistoric earthquake), lake levels began to rapidly decline in Bonneville floods,” Speeden concludes during a 12-minute video presentation of the GSA meeting results.

He added that it is possible that the seismic accident “killed” Lake Bonneville and the southeast area of ​​Salt Lake County, which he called the “Gilbert Basin”, was a “smoke gun.”

An unlikely path to search

What might make the look even more fascinating is how it fits. In fact, Spedden is perhaps the most surprising person as he is presenting his findings at the GSA annual meeting this week. Not that he was shocked that scientists were willing to listen and review his results, because geology is not his day-to-day job or his main expertise.

The study became an outlet for an urgent desire to understand how the terrain formed. He did not expect his research to be related to Lake Bonneville in any way when he began.

“It was not my intention to disable anything,” he admitted. “I wasn’t really looking to invent something new. All I was trying to do was understand the Little Cottonwood side rubble because when I looked at it, it didn’t fit the existing explanation of why it was the way it was.”

Screen capture of Richard Spiden from a pre-recorded 12-minute presentation on his geological discovery. Spedden recorded the introduction at GK Gilbert Geologic View Park in Sandy. (Photo: Courtesy of Richard Speeden)

He contacted local geologists with his theory early on but the idea was rejected. A geologist suggested Spedden put together a peer-reviewed paper, which is exactly what he decided to do. For him, the “moral obligation” to inform the scientific community of what it believed it had discovered outweighed what he said was difficult work.

He had heard a mixed bag of comments since finishing the paper. A representative from the United States Geological Survey gave a glowing review. Another reviewer disputed some findings based on previous research – criticism Spedden ignores. For him, his presentation on Friday marked the end of his goal of showcasing what he discovered.

“I have enjoyed others’ work in this field for many years, and if I can get the ball forward, that would be amazing,” he said.

Future studies

If Spedden is correct about his research, he is optimistic that it will lead to future discoveries about land around Intermountain West that were submerged under Lake Bonneville and determine exactly what happened thousands of years ago.

It is not just something that would change history, but it has current implications. For example, it was suggested that this might imply the need to re-evaluate Wasatch Fault’s slip rates for future ground motion. It is also something that may have implications for the land as reservoirs and dams are in the area.

As for his future, Spedden doesn’t expect to do another geological study himself – that’s unless he finds himself in another rabbit hole. He joked that he completed his contribution to the field whether or not geologists wanted to accept it.

As he awaits more comments about his work after his presentation this week, he also hopes that residents will find similar interest in the unique terrain.

He said, “I firmly believe that we all just need to go through our lives and learn as much as possible about everything around us. It makes life more interesting.” “I mean everyone looks at their backyard, and they think it has always been this way; but every time I look at Salt Lake Valley, I imagine a canyon filled with this huge lake with glaciers flowing down the lake.

“It must have been really amazing and that’s fun to think about.”

Carter Williams More stories that may interest you.

What Are The Main Benefits Of Comparing Car Insurance Quotes Online

LOS ANGELES, CA / ACCESSWIRE / June 24, 2020, / Compare-autoinsurance.Org has launched a new blog post that presents the main benefits of comparing multiple car insurance quotes. For more info and free online quotes, please visit https://compare-autoinsurance.Org/the-advantages-of-comparing-prices-with-car-insurance-quotes-online/ The modern society has numerous technological advantages. One important advantage is the speed at which information is sent and received. With the help of the internet, the shopping habits of many persons have drastically changed. The car insurance industry hasn't remained untouched by these changes. On the internet, drivers can compare insurance prices and find out which sellers have the best offers. View photos The advantages of comparing online car insurance quotes are the following: Online quotes can be obtained from anywhere and at any time. Unlike physical insurance agencies, websites don't have a specific schedule and they are available at any time. Drivers that have busy working schedules, can compare quotes from anywhere and at any time, even at midnight. Multiple choices. Almost all insurance providers, no matter if they are well-known brands or just local insurers, have an online presence. Online quotes will allow policyholders the chance to discover multiple insurance companies and check their prices. Drivers are no longer required to get quotes from just a few known insurance companies. Also, local and regional insurers can provide lower insurance rates for the same services. Accurate insurance estimates. Online quotes can only be accurate if the customers provide accurate and real info about their car models and driving history. Lying about past driving incidents can make the price estimates to be lower, but when dealing with an insurance company lying to them is useless. Usually, insurance companies will do research about a potential customer before granting him coverage. Online quotes can be sorted easily. Although drivers are recommended to not choose a policy just based on its price, drivers can easily sort quotes by insurance price. Using brokerage websites will allow drivers to get quotes from multiple insurers, thus making the comparison faster and easier. For additional info, money-saving tips, and free car insurance quotes, visit https://compare-autoinsurance.Org/ Compare-autoinsurance.Org is an online provider of life, home, health, and auto insurance quotes. This website is unique because it does not simply stick to one kind of insurance provider, but brings the clients the best deals from many different online insurance carriers. In this way, clients have access to offers from multiple carriers all in one place: this website. On this site, customers have access to quotes for insurance plans from various agencies, such as local or nationwide agencies, brand names insurance companies, etc. "Online quotes can easily help drivers obtain better car insurance deals. All they have to do is to complete an online form with accurate and real info, then compare prices", said Russell Rabichev, Marketing Director of Internet Marketing Company. CONTACT: Company Name: Internet Marketing CompanyPerson for contact Name: Gurgu CPhone Number: (818) 359-3898Email: [email protected]: https://compare-autoinsurance.Org/ SOURCE: Compare-autoinsurance.Org View source version on accesswire.Com:https://www.Accesswire.Com/595055/What-Are-The-Main-Benefits-Of-Comparing-Car-Insurance-Quotes-Online View photos

Picture Credit!