The purpose of this paper is to explain and highlight different aspects of the Powder River Basin to include paleogeography, stratigraphy, maturation history of organic material, vitrinite reflectance data, sulfur content, both historical and current production data, as well as the environmental impact in the basin.
The Powder River Basin is located in southeast Montana and northeast Wyoming. According to Luppens et al. (2008), the Powder River Basin is approximately 22,000 square miles in area. The basin itself trends in a north-to-north west direction. The eastern side of the basin dips gently westward, whereas the western side dips much more steeply towards the east. This forms an asymmetrical syncline with the synclinal axis lying closer to the western margin of the basin (USGS, 2013). The Powder River Basin is structurally separated from other basins by Laramide style tectonic landforms, where large portions of Archean basement rock were thrust upwards during the late Cretaceous and Paleocene (Flores, 2004). In Wyoming the Powder River Basin is surrounded by the Bighorn Mountains to the west, the Black Hills to the East, and the Laramie Mountains, Casper Arch, And Hartville Uplift to the South. To the north, in the Montana portion of the Powder River Basin, the Miles City Arch separates the basin from the Williston Basin in North Dakota. The coal beds that were deposited in the basin are mainly sub-bituminous but can also be lignite in rank and range from Cretaceous to Eocene in age. There are four formations that contain coal beds in the Powder River Basin and include the Mesaverde Formation, the Lance Formation, the Fort Union Formation, and the Wasatch Formation. Each of these formations contains several different coal ...
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...he future with better methods and techniques.
Summary
The Powder River Basin coal beds are some of the thickest in the world helping to make the basin one of the top producers not only nationally but globally as well. Although the coals are low rank and therefore not ideal for producing electricity, the sheer amount of coal in the basin makes it very economical to mine these coals. The low ash and low sulfur content of the Powder River Basin coals also make the coal ideal for the current marketplace. The low ash and sulfur content helps to make these coals relatively environmentally friendly in comparison to coals that are mined from places like Illinois, which have higher sulfur contents. The vast amount of resources that the Powder River Basin contains makes this region of the United States a major player when it comes to supplying energy for the next century.
Marshak, S. (2009) Essentials of Geology, 3rd ed. New York: W.W. Norton & Company, ch. 11, p. 298-320.
Sedimentary rock from the older Silurian Period is further from the river banks (Geological map of Victoria, 1973). Mudstone, inter-bedded shale and greywacke depositions indicate the Maribyrnong River may have previously taken a different shape, and younger sediments have replaced the older sediments in more recent geological periods.
Rising from the Plains by John McPhee is about an influential geologist, John David Love, interpreting the geologic history of Wyoming. The surface area of Wyoming has been subjected to many geological formations from the rise of the Rocky Mountains through the Laramide Orogeny in late Cretaceous time to the deep structural basin known as the Jackson Hole with rock dating back to the Precambrian period. Throughout each time period of the Earth’s history, the surface of Wyoming has experienced significant changes that have affected the physical landscape, as well as living organisms, even to this day. In this story John David Love shares his knowledge of the geologic history of Wyoming with John McPhee as they travel across Wyoming taking in the vastness that the landscape of Wyoming presents.
Glaciers are an integral part of the world’s climate. In fact, as Richard Armstrong of the University of Colorado says, “Glaciers are key indicators in monitoring and detecting climate change” (Univ. of Colorado, Boulder, 2003, p. 1). Not only are they an important part of monitoring current climate, they can hold many keys to the past. Glaciers are in fact, “a source of paleoclimate data…” (Meier and Dyurgerov, 1980, p. 37). This paleoclimate data can give geologists information on the conditions that were present at the time of the glaciers birth, as well as the approximate age. This has an important role in the geologic time scale of the Colorado Rocky Mountains. These Glaciers played a role in the carving of the present day Rocky Mountains in Colorado, which will be the primary focus of this paper. In addition, glacial formations will be discussed to give the reader background information and the future of the Glaciers in Colorado will close this paper.
Removal of the mountaintops causes environmental impacts from blasting. The blasting has caused rocks to be deposited into valleys on the hillsides, burying almost 2,000 miles of streams which feed the Mississippi River. Slurry, the residue which is used to clean the coal can wash into groundwater and may contain arsenic, lead, manganese, iron, sodium, strontium, and sulfate. A recent research study is beginning to link these environmental impacts to the grave health concerns in the Appalachian communities. During most of the Mountaintop removal mining’s history coal industries have been able to obtain permits easily to operate, but once under the Obama administration Environmental Protection Agency (EPA) those permits now take more time to obtain. The permit process requires all applications to be reviewed before being given out to coal
A machine known as a dragline then digs into the rock to reveal the coal, the machines hollow out the tiers of coal and dump millions of overburden, the previous mountaintops, into constricted nearby valleys, thereby producing valley fills. Coal companies have covered over 1,200 miles of biologically crucial Appalachian headwaters streams.
The sharp differences in elevation between the Badwater Basin and the surrounding mountains that include the highest point in the continental US (Mt. Whitney at 14,494 feet) stand as a representation of the regions violent tectonic past. The mountains themselves are considered fault block mountain ranges meaning that they were formed when blocks of rocks were squeezed through the Earth's crust along parallel faults or were loosened from the crust when it separated at a fault. In the valley, both of these methods not only were the cause of the current mountains formation less than four million years ago, but also are causing the mountains to be uplifted while the valley floor drops even further. This phenomenon is one of the reasons why the lowest and highest points in the continental...
Endangered Plants and Animals of Oregon, by the Agriculture Experiment Station at Oregon State University.
Americans today tend to believe that the Colorado River drought has been a recent occurrence, although drought relief strategies have been implemented since early 1997. To summarize, in the book The Colorado River Basin Drought Planning and Organizations, Colorado is named as the original state to acquire a drought relief plan. For instance, various assume water levels are diminutive in the Colorado and blame is due to the previous ten years of drought throughout the United States. Although it is true that water levels are at a record low, initial plans in the early 1920’s to introduce manufactured structures into the water basin is the original reason Colorado’s water system began to be compromised. It follows, then the supplementary natural
Eckel, Edwin B., ed. Nevada Test Site. Memoir 110 Boulder, CO: The Geological Society of America, 1968
although having water available for economic development is important, the growth of industry cannot be allowed to take precedent over protecting the most valuable resource of all, the individuals of each nation.
Valley Region of the Appalachian Mountains and Subsequent Karst Regions in the State of Virginia
...se two tectonic plates generated intense friction and pressure that generated enough heat to melt rocks. The descent of denser oceanic Farallon Plate into the asthenosphere produced magma that was made from basalt or andesite. Which is dark colored rocks with little silica. The buoyant magma pushed through the silica-rich continental crust, partially melting the crust that it moved though, and becoming more granitic in composition. About 100 million years ago, the granitic magma pooled at depths of only 2 to 5 miles beneath the surface (United States of America). The granitic terrain that makes up the Sierra, was once thought to have only local variations but was produced from one large mass of rock. It has been discovered however that hundreds of intrusions caused the variations in the granite that is displayed in Yosemite and in the Sierra Nevada range (Huber).
Blakey, R. C. (1996). Geologic history of western us. Informally published manuscript, Northern Arizona Univ, Flagstaff, AZ, Retrieved from http://www.jan.ucc.nau.edu
Hussey, Russell C. Historical Geology: The Geologic History of North America. New York: McGraw-Hill, 1947. 379. Print