Geog 431 Book Review: John Mcphees Rising Through the Plains PDF

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This is a detailed essay covering John Mcphees book, 'Rising Through the Plains". It is one of the books offered in the class that students may choose to discuss. ...

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John McPhee: Rising from the Plains Book Review 1.) John McPhees book “Rising through the Plains” tells the journey of him traveling through Wyoming with a Rocky Mountain geologist, David Love. While McPhee drives, Love is in the passenger seat lecturing about the geology of the Wyoming landscape. The first geologic event that Love talks about is the Rawlins uplift. The Rawlins uplift happened on the eastern side of the Great Divide Basin and the southeastern end of Western Wyoming. It is a small Laramide Uplift *(8) that has many of the characteristics of larger Wyoming ranges. As they continue through Wyoming, they travel and stop at many road cuts that extend through the highway. Continuing through the road cuts Love discusses some of the rock formations and types that are exposed, such as frontier sandstone, bentonite, which is a volcanic tuff-decomposed and devitrified, and Mowry shale. These road cuts serve as portals to long digressions of the geologic history of Wyoming and these rock types are found all throughout Wyoming and the Rocky Mountains. Another landform that stands out that Love mentions is the Crowheart Butte, which rises 1000 feet above the surrounding landscape and is capped flat with sandstone. As we dive a little farther into the book, they drive into the Laramie Range, which is a prominent part of the books geology. The foreland ranges of the rocky mountain region, the Wind Rivers, Uinta’s, Bighorns, Medicine Bow, Snake River Range, and the Grand Tetons all came into the world with the tectonic interpretation of Laramide orogeny. Mostly, throughout this book, Love discusses the geology through a lens that provides the reader with a more humanized view of geology. Someone interested in Landforms would appreciate the structure of this book and how it provides an easier understanding for the reader to put geologic time periods into perspective. McPhee uses Loves information and transforms it into a story of time. The way McPhee humanizes the geology provides the reader with a greater advantage of understanding the physical geography and topography. In general, the reader will learn specific terms, different rock types, periods, and age names, and events that caused the Wyoming landscape today, being able to relate all of them together forming a story. 2.) One of the main sections that interested me that McPhee discusses is the Grand Teton National Park. The Teton Range is forty miles long and less than ten miles across. McPhee discusses several different glaciated landforms, and river networks within the Teton Mountains, as well as, the history of there existence. The Teton Mountains are North-South trending and rise between 5000 and 7000 feet higher than Jackson Hole. Grand Teton rises to 13,747 feet, which is the highest out of the Mountain range. There are a vast number of stream networks that flow throughout the Tetons; however McPhee mentions two: Spread Creek and Fish Creek. Spread Creek, on the eastern side is a tributary creek with two mouths, with the stream flows three miles apart from each other. Fish Creek which runs along the base of the Teton Mountains is also a tributary of the Snake River and is a formation of snowmelt and tributary streams. In the middle of Spread Creek and Fish Creek runs the Snake River which is about 15 feet higher in elevation and is seen flowing down the center of Jackson Hole, which also contains levees that keep it from spilling west. The Tetons contain alpine glaciation, alluvium and outwash deposits flowing out of the canyons and there are a number of lakes that are seen throughout the Tetons at altitudes up to 10,000 feet, such as, Snowdrift Lake, Leigh Lake, and Icefloe Lake. (Pg 130). Each lake is located at the foot of the Tetons, which is evidence of Alpine glaciation and moraines. The Tetons also contain a number of glaciers, such as Teton, Middle Teton and Mount Owen. All of these glacial features formed during the recent ice ages. McPhee describes different features that could explain history of the Tetons. Love noticed the mountain asters are always facing towards the east, the boulders far from the

bedrock from where they originated, and how he discovered many faults through the valley floor. McPhee also mentions two different Buttes with location adjacent to the mountains and were formed from two different episodes of Volcanism, and all the streams that flowed downward and then looped in different directions. With the topographic features residing in the landscape, McPhee attempts to explain the history and formation of these landforms through the history of the uplift of the Tetons (Pg 131). 3.) The Laramide Revolution is what created the Teton Mountain Range. The Teton Mountain range was formed between 6 and 9 million years ago, creating the youngest range of the Rocky Mountains. The Teton Fault lies west of the Jackson Lake and runs along the eastern base of the Tetons, which faulted vertically and dips east. The Tenton fault is also an important feature that is a part of a larger region of seismic activity, called the Intermountain Seismic Belt, which extends through western Montana to Northern Arizona. The Snake River, which McPhee talks about, runs down through Jackson Hole. Snake River is an antecedent river and was started as a moisture channel fed by rains that eventually made its way cutting down through the Tetons. It is a meandering River, with many tributary streams flowing into from the Teton Mountains. These mountains contain many features which are mostly glaciated, and have played a key role in forming the Tenton landscape. The Tetons have gone through two different glacial periods, the Pleistocene ice age and Pinedale. Each ice age played a part in the carving and formation of valley lakes, created by moraines and fluvial activity. In the Book, McPhee talked about boulders far away from their original bedrock, which is also evidence of the glacial activity. All of the glaciers lie on the eastern slope of the Teton Range, which is most likely due to the decreased solar radiation and western winds.

Mount Moran, Leigh Lake -glacially formed lake

Jenny Lake -Glacially formed lake

Seismic Belt, Teton Fault The arrow is pointing to the Intermountain Seismic Belt

Normal Fault

*The Laramide orogeny is the process that is responsible for the creation of the Rocky Mountains. They conclude that the Rocky Mountains were formed when an oceanic plate was subducted underneath a wide mantle plume and hot spot. This created the wide and distinct location of the formation. Due to the hot spot underneath the continental plate, there was a warming and melting of continental crust, which caused the density of the plate to decreaseThis sketch shows the plate tectonic setting during the growth of the Rocky Mountains (Laramide orogeny). The angle of the subducting plate is significantly flatter, moving the focus of melting and mountain building much farther inland than is normally expected....