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TTC - James F. P. Cotter - Practical Geology


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[b]TTC - James F. P. Cotter - Practical Geology[/b]
Size: 10.34 GB Type: Elearning Year: 2022 Version: 2022


Course Overview

Have you ever picked up a rock and admired its colors, crystals, and texture, and thought, "How did it get this way?" Or have you ever driven by an unusual landform and wondered, "Why is it like that?" These questions have surprisingly deep answers that can encompass a significant fraction of Earth's 4.6-billion-year history. Such revelations come from the science of geology, but you don't have to be a professional geologist to look at a rock or a landscape and read its amazing story.

Geology is probably the most accessible and enjoyable of all the sciences. You can do it almost anywhere. The equipment you need is minimal. It takes you outdoors, often to spectacular places. Best of all, the insights are astonishing-and practical. Consider these geological observations from everyday environments:

Sand: On beaches, playgrounds, golf courses, construction sites, and icy sidewalks, sand is ubiquitous, and it bears close inspection. The mix of minerals that make up the grains can tell you where the sand comes from. It may well derive from now-vanished mountain ranges, volcanoes, or coral beds.
Granite: Many kitchens have granite countertops. But are they really granite? The term is used loosely by contractors. Real granite has three types of visible minerals, all about the same size, without a larger structure or pattern. Other natural surfaces sold as granite might have different properties.
Soil: A garden or yard is a good place to do field geology. You can start by examining the soil profile by using a small shovel to dig down a foot or so to inspect the distinct layers, called horizons. They can tell you the history of the soil, its fertility, and possible deficiencies you may want to correct.

These and a multitude of other observations and insights are presented in fascinating detail in Practical Geology, 24 half-hour lectures that take you from your backyard to geologic sites around the world, through eons of time, and even to another planet. Geologist James F. P. Cotter of the University of Minnesota, Morris, is your instructor. A multi-award-winning teacher, James presents an enlightening guide to elementary geology, expertly conducting you through dozens of on-camera demonstrations, showing off scores of rock samples, and advising you where to go and what to take to make geology an exciting and integral part of your life.

"Learning about the Earth should be participatory," he says. "Like recognizing trees or birds, being able to identify geologic features and different rock types will help you understand and appreciate the world around you."

Dream Destinations for Practicing Geology

The course covers a dream list of geologic destinations, many in North America, including the Grand Canyon, Yellowstone National Park, Washington's Channeled Scablands, Yosemite National Park, Michigan's Upper Peninsula, the Mississippi River Delta, and Alaska's Matanuska Glacier. Not everyone can make such trips, but you can still practice geology in your immediate surroundings, wherever you live.

Every place on Earth's surface is rife with evidence of past events. They may be colliding tectonic plates, volcanic eruptions, continental glaciers, periodic floods, disappearing oceans, asteroid impacts, or now-extinct life-forms. The clues are usually subtle, but Practical Geology teaches you how to read the signs and encourages you to hone your skills in productive settings such as these:

Outcrops: You pass by outcrops all the time, especially on highways where roadcuts are ideal outcrops. They are like X-ray images of the local geology. If state law allows, pull over and see if you can decipher what's going on. Professor Cotter provides safety tips and recommends resources and strategies.
Gravel pits: The poor man's glacier, gravel pits are often ready-made excavations into glacial deposits. Some pits have sediments that represent almost every type of geologic process-rivers, wind, mudslides, glacial tectonics, and lakes. Organized trips are best, due to the inherent risks of open-pit mines.
Caves: Caves are very common in areas underlain by limestone, dolomite, or gypsum. In the United States, many cave formations record the time when North America was covered in ice sheets. Again, safety first! Cave exploration is an activity to be pursued only with an experienced group.

Rocks, Minerals, Gems, and More

Rocks come in three major classes-sedimentary, igneous, and metamorphic-with seemingly limitless variety in each class. From sandstone to shale to hematite, sedimentary rocks reveal processes at work near Earth's surface, such as weathering, transport by wind and water, and deposition and compaction. Igneous rocks range from super-porous volcanic rocks like pumice, which cooled quickly from molten lava, to granite, which took millions of years to cool from magma deep underground. By contrast, metamorphic rocks have undergone a metamorphosis, being transformed by heat, pressure, or other natural forces into something very different from the parent rock. For example, limestone and dolomite turning into marble, or sandstone into quartzite.

Professor Cotter also delves into minerals, which are the substances that make up rocks. And he discusses crystals, the form that minerals take. He explains the conditions that create oil, gas, and coal, and how they are extracted. And he takes you hunting for some highly prized products of geologic forces, including these:

Gold: It's still possible to pan for gold, just like the Forty-Niners during the Gold Rush. But first you need to zero in on streams that are the best bet, which means understanding how gold gets into rivers to begin with. Knowing where igneous rocks and hydrothermal activity have occurred is a big help.
Gems: Gemstones are mostly hard crystalline minerals that can be cut and polished to create jewels. In other words, they're beautiful-but not in the rough, where they often look like ordinary rocks. Learn how different gems form, where they can be found, and fruitful prospecting techniques.
Fossils: Fossils are the preserved remains and traces of ancient life. They are so abundant that it's not hard to find them-if you know where to look. Professor Cotter explains the geologic formations that are most likely to harbor fossils, what life-forms to expect, and the dos and don'ts of fossil collecting.

Be Prepared

Astronomers have their star charts, chemists have their periodic table, and geologists have their maps-both topographic and geologic. Practical Geology tells you how to access paper and electronic versions of these indispensable charts for whatever region you're exploring. Professor Cotter also provides tips for selecting a suitable rock hammer-which costs no more than a carpenter's hammer-and he instructs you how to use it. Along with the rock hammer, you'll want gear that you may already own: outdoor clothing, sample bags, backpack, water bottle, cell phone, GPS device or compass, sunscreen, and it's always a good idea to have a companion or two. He gives further advice for exploring potentially risky sites such as deserts, active volcanoes, and glaciers. All are reasonably safe if proper precautions are taken.

It's hard to think of a more invigorating and mentally engaging activity than geology. Wherever you go, the rewards are fresh air, interesting scenery, and an absorbing puzzle to solve. A century and a half ago, Grand Canyon explorer John Wesley Powell described the glories of field geology: "I climb up the granite to its summit and go away back over the rust-colored sandstones and greenish yellow shales, to the foot of the marble wall. . All about me are interesting geological records. The book is open, and I can read as I run."

After taking Practical Geology, you, too, will be able to contemplate nature's glories and read the gripping story of the geological record.




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