Disclaimer: Only one of the locations we visited on this field trip was in Idaho, the other two are in central Utah. However, since the Salt Lake Valley is only 4 hours from East Idaho, I am okay sharing this recent adventure with you all on here!
So, as you can see, we drove to the Salt Lake valley in central Utah as a part of a two-day geology field trip for my Igneous and Metamorphic Petrology class! For those not versed in the language of geology, our studies this semester have been centered on the geologic processes associated with volcanoes and the compression and alteration of rocks well below the surface of the earth. Utah is well-known for its beautiful red-orange sedimentary rock features such as those found in Arches National Park and Moab in southern Utah. To be honest, I hadn't realized just how incredible Antelope Island, found in the Great Salt Lake, truly was until this trip! The Island is made up of rock that formed anywhere from a few billion years ago to only 500 million years, while the islands shape has been altered drastically, folded and faulted by large mountain building events within the last 100 million years, then immersed in the rise and fall of Lake Bonneville which once covered much of Utah and parts of Idaho with depths exceeding 1500 ft. The region tells stories of intense glaciation, powerful eruptions, colossal convergences of rock bodies and so much more! The rocks have locked a few chapters of their long history within each mineral and feature we can see. It is remarkable how much we can gather and interpret from observations made across our planet. Even more incredible is realizing that the recorded rock history we do have access to only accounts for a small fraction of our earth's history! We studied a portion of Antelope Island where almost a billion years of earth history has simply not been recorded and rocks of much younger age sit atop multi-billion year old rocks. This lost record is not unique to just the Salt Lake Valley, but much of the western portion of North America. We have no evidence of the geologic history of this vast area for over a billion years! That is an incomprehensible amount of time.
Now, geology aside, I have to say, this island offers a pristine vista that allows for an unobstructed 360 degree view of much of central Utah! The island rises above the lake level nearly 2500 ft with scattered trails and campgrounds accessible across the island. This is a State Park so general access and camping does require a fee, something like $15 per vehicle and $40 a night for camping. There are essentially no trees on the island, just some super cool, really old rocks! That and a lot of sage brush. The island is home to a herd of bison, rabbits, antelope, coyotes, and more. It is remarkably quiet during the evening hours, and the trails and roads are well maintained. It can be somewhat crowded on the weekends, but we found several areas where we could hike and sit away from people. With near-surreal views, and a unique and stark landscape, this island is well worth the day-trip south!
The two other stops we made include Hell's Half Acre (south Idaho along I-15) and Little Cottonwood Canyon (central Utah). Hell's Half Acre is a somewhat recent lava field associated with Craters of the Moon to the distant west. The multi-flow lava field features intact and collapsed lava tubes, flow features, fractures, and much more distinct features of a basalt lava flow. Little Cottonwood Canyon is famous for many reasons, and deserves a whole post to itself, but our time spent there was short, and I haven't spent the time there that would allow me to do justice to what this canyon has to offer. It is busy, but for good reason! Well worth multiple trips to discover it for yourself!
Below are a few of the 200+ pictures I took this trip, enjoy!!