Geology 101 Final Exam - Option A Fall 2002 You can come and take an exam that is open book (you can use any notes or books you wish). This exam will be similar to others we have had, but will be longer. Except for material on Chapters 22 and 23, questions will come from other exams this semester, from the study questions on the old exam page, or from the list of three below. 1. How was the world different during the glacial advances of the Pleistocene ice age? Be sure to mention the relation between glaciations and sea level and describe where glacial ice was located during glacial maximums. 2. We humans have seen a great deal of climate change in modern time (we have experienced it) and the changes also occurred in pre-human time. What is the most important and compelling evidence that allows us to track climate changes in the geological past? After all, there were no people around. 3. Climate change takes place over long periods of time (100s of thousands of years or greater) and over shorter periods of time (from tens of thousands of years down to just a few decades or years). What are the causes of both? How do we know this? Of course you should look at the old exams. I will surely use a lot of the same multiple choice questions. (But, there will be new ones from the lecture and book material.) And, some questions will relate closely to the questions at the end of the Chapters.

Geology 101 Final Exam - Option B Fall 2002 (No true-false, matching, or multiple choice questions only short-long answer.) Below are 12 questions. Some will be on the final; probably less than half of them. I don't know which, yet. Sorry guys, but I don't have the 200 hours (10 minutes x 100 students x 12 questions) it would take to do the grading if you answered all of them. Some of the questions are relatively straightforward, but some of the questions have less specific correct answers. So, you have choices in the way you choose to answer them. However you choose to answer them, make your answers logical and consistent and explain well. Be sure to spell well, and use both verbs and nouns, in proper order, in all sentences. 1. Quartz comes in many different colors. But, when euhedral (look this word up if you don't know it) it is almost always vitreous and crystals have hexagonal shapes. Quartz never shows cleavage, always has a hardness of 7, and its density is always around 2.65 grams/cm3. Explain why almost all properties are identical for all samples of quartz. And, explain why color can be variable. Note that I could have chosen just about any other mineral and asked the same question. 2. Clearly explain to me the difference between elements, rocks and minerals. What are the most common elements in the Earth's crust? Why are they so common? What are the most common rocks (give rock names)? Why are they so common? What are the most common minerals (give mineral names)? Why are they so common? 3. Mineralogists have identified thousands of minerals, yet less than 30 are common, and less than 15 are very common. Why so few common minerals? 4. Basalt, andesite and rhyolite are the three types of igneous rocks I told you to know about. What minerals are in each. Are these rocks volcanic or plutonic? If they are volcanic, what are their plutonic equivalents? If they are plutonic, what are their volcanic equivalents? What are the most significant apparent difference between volcanic and plutonic rocks? What major minerals are contained in each of the three rock types (basalt, andesite and rhyolite)? Why do the different rock types contain different minerals? 5.Why are some volcanoes more violent and dangerous than others? Be specific about the reasons; there are several different ones. Don't just tell me what the different types of volcanoes do, tell me why they behave the way they do. Most of the volcanic material deposited by Mt. Rainier is ash or pumice. Contrast this with the material that is deposited by Hawaiian volcanoes. What sort of volcanic rocks (what is the name of the rock type) are in Hawaii? Why are they different from those in the Cascade Range? 6. What are the most common kinds of sedimentary rocks? Give rock names and tell me what minerals they contain. Why are these kinds of rocks the most common? 7. Some sedimentary rock formations are found over very large areas. The Pierre Shale, for example, is a Cretaceous formation found in many states of the Great Plains and Rocky Mountains. Some formations, however, only crop out in a single state or even a single part of a state. Explain why some formations have wide extent, while others do not. 8. High grade metamorphic rocks are those that form at high temperature. Low grade metamorphic rocks form at lower temperature. Give an example (give me a name and list major minerals) and describe one of each type of metamorphic rock. One thing that controls metamorphic grade is depth in the Earth. Which of these two formed at shallow levels in the Earth and which at deeper levels. Explain why? If we find metamorphic rocks today and determine that they must have formed deep in the Earth, how did they get up to the surface so we can find them? 9. The centers of most continents contain "shields" where very old igneous and metamorphic rocks are exposed in flat lying areas. They also contain platforms - areas of flat lying sedimentary rocks on or adjacent to shields. Why are there shields and platforms only in the middles of continents? We find most mountain belts at the edges of continents. Why do mountains mostly only form at the edges of continents? Every once and a while we find mountain ranges in the interior of continents. The Rockys and the Ural Mountains are examples. Explain how they formed (different for each) and ended up where they are. If you looked at a map of the world showing locations of volcanic activity, you would find that most volcanoes are at the edges of continents - just like most mountain ranges are. A few volcanoes are in the middle of oceans, and even fewer in the middle of continents. Explain why volcanoes occur where they do. 10. If you look in any introductory geology book, there is generally a cross-section drawing of the earth with the crust, mantle and core labeled. This is one way to describe layers in the earth. Often, too, a drawing is shown with the asthenosphere and lithosphere labeled. That is another way to describe layers in the Earth. Why do we have two different schemes for labeling the layers in the Earth. How do the two relate? How do geologists know that those different layers (crust, mantle, core, asthenosphere and lithosphere) exist? What is the key evidence and information? 11. The groundwater of the Red River Valley flows up and out of the ground in many places. Explain why and how water can flow uphill like that. Most of the groundwater in the Red River valley is saline and the recharge area is a long way away. Explain why. Some is freshwater, and the recharge for the freshwater is generally closer to the Valley than the recharge areas for saline water. Explain why? What I am getting at is: where do the two types of water come from and why is some fresh and some saline? 12. Climate change takes place over long periods of time (100s of thousands of years or greater) and over shorter periods of time (from tens of thousands of years down to just a few decades or years). What are the causes of both (long term, and short term changes)? How do we know this? At Glacier Bay, John Muir discovered that glaciers had retreated over 45 miles. Why do glaciers retreat sometimes and advance other times? Be specific about the mechanisms/processes involved. Around the world today, almost all glaciers are retreating. Why do you suppose there was so much retreating at Glacier Bay and elsewhere in the last 150 years? Occasionally glaciers surge (advance very rapidly), even today. Why does this happen?