As I mentioned in a previous post (Young family), in 1847 Brigham Young had recently ascended to the presidency of the LDS church. In an effort to escape religious persecution in the eastern United States, Young lead the first band of Mormons west to settle in the Salt Lake Valley, which was not yet part of the United States. The settlers arrived in the Salt Lake Valley on July 24, 1947, a date now celebrated as Pioneer Day in Utah, and under Young's guidance strove to become a self sufficient colony. In 1848, after suffering some earlier minor setbacks due to a late frost, a plague of crickets descended on the settlers crops causing severe damage and threatening the survival of the settlers. On June 9, 1948 legions of gulls are said to have appeared, gobbling up the hordes of crickets and saving the settlers remaining crops. Many mormons viewed the arrival of the gulls as a miracle and the incident is prominent in Mormon folklore. To ths day the Califonia Gull is the state bird of Utah.
I don't know if the Miracle of the Gulls has anything to do with the naming of the Cricket Range but crickets are clearly important in Mormon early history.
Of course I was in the Cricket Range to look at rocks. At this location I was looking, for the first time, at the Cambrian Prospect Mountain Formation and the underlying Mutual Formation. These units had been mapped in the area and I found them precisely where they had been mapped. Here's a shot of the Mutual Formation (foreground) with the overlying Prospect Mountain in the background.
Immediately west of the Cricket Range is Sevier Lake, an endorheic lake. Endorheic lakes are lakes with no outflow where all the water that enters the lake basin either evaporates or seeps into theground. Some of the worlds largest inland water bodies such as the Aral and Caspian seas are endorheic. Sevier Lake has, for the majority of recorded history, been a dry lake bed but occasionally during periods of higher than average rainfall the lake temporarily fills. I didn't note any water while I was there.
The majority of the land within the Cricket Range is BLM land (see explanation here: Summary of US Land Administrators) and therefore the peoples land. You are permitted to camp almost anywhere with a few restrictions regarding proximity to water sources. I met a very interesting and older couple who were camping near my sample location. It is not unusual for people, once the find out you're a geologist, to want to have you look at their rock collections. Normally I try to express some enthusiasm for the rocks in the collection as I try to support the general public's interest in the geosciences whenever I can. However, the first rock I was handed was about as boring a sandstone as you could imagine. Part of me wanted to ask "what exactly possessed you to pick up this rock?". However, I dutifully pulled out my hand lens and went about describing the mineraology and texture of the rock. Thanfully the next rock in the collection was a limestone with abundant bivalve shells and I was saved the awkwardness of having to feign interst in rocks that are uninteresting.
One last piece of geology before I move on from the Cricket Range. Unlike my earlier stops in the eastern part of my thesis area, these western mountains are not the direct result of contractional or compressive plate tectonic processes (a.k.a mountain building). These mountains were formed as part of Basin and Range extension which began in this area around the Early Miocene (~23 million years ago) and are therefore much younger than the mountains to the west which formed in the late Cretaceous and early Paleocene (>55 million years ago). One fo the faults associated with this recent extensional phase of deformation occurs immediately west of the sample area and is the reason Sevier Lake exists. This fault clearly affected the rocks in the sample area and several smaller faults were present in the section. Here's a cataclastic rock or a rock that has been shattered by stress associated with the nearby faulting. The right side of the boulder is undeformed Mutual Formation. The left side is the same formation but broken up by the stresses associated with the fault.
After finishing my work in the Cricket Range I headed over to Fillmore, Utah for the night. I am staying in a KOA and will go sample some rocks near here tomorrow before heading to the eastern Uinta Mountains tomorrow.
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