EXAM 3 GEOL 101 PDF

Geology 101 spring 2022 potential exam questions and word list 1)Describe the differences between absolute dating and relative dating . How are they similar? How are they different? What tools/methods do geologists use for absolute dating? What tools/methods do geologists use for relative dating? Absolute Dating: Is a very specific date or date range. Tools/ Methods: Radioactive Decay (Parent-Daughter Isotopes), and Radiometric Dating. Relative Dating: determining the relative order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age. Tools/Methods: Principle of Superposition and Fossils. BOTH are used to tell an order of events in earths history. 2) Draw a block diagram of an angular unconformity. What are the four geological processes (in order) that would be required to develop that type of unconformity?

1.Sediments were deposited horizontally then compressed to become rock 2.Tectonic forces deforms the rock, causing it to tilt 3. Erosion weathers the rock 4. A second layer of sediment is deposited horizontally and becomes rock 3) What are the similarities and differences between body fossils and trace fossils. Provide an example of each. Body Fossils: Actual remains, may be a "chunk" of an organism, i.e. leaf or a shark tooth Trace Fossils: Imprints, think of what a trace is... Something left behind (indirect evidence), i.e . Tracks and Burrows. Similarities : both can be helpful in relative dating.

5) Examine the geologic cross - section below. Which feature is the youngest? a) H Which feature is the oldest? b) T (A diagram would be provided similar to your mastering geology assignment)

6) Identify and describe the four principles of relative dating that we discussed in class. For each draw a diagram that illustrates the principle. • Law of superposition: Each unit older than one above • Original horizontality: Sedimentary rocks deposited horizontal • Cross cutting relations: Fault or intrusive unit cut another unit, The rock must be older than feature • Inclusions: If a rock contains another, younger than source rock 7) What is an index fossil? Describe three characteristics of a fossil that would make it a useful index fossil. Index Fossil: Fossils widespread, and commonly found, and have a limited span of geologic time. As for Characteristics: A : Short lived. B : Easily Identif i able. C : Widespread. 8) Describe how a geologist could determine the age of a rock by measuring the concentration of certain elements. What makes these specif i c elements special? Depending on what fossils or elements the rock has, you can narrow it down to when each elements lived, and find a frame of time that can tell you when the whole rock might have formed.

- 11) When examining the geology of a region for potential aquifers, what characteristics or factors would you consider? Are there any specif i c rock types you would want? Any to avoid? Also, what areas (based on natural and human factors) would you avoid? - Want: o permeable rock. o high rates of rainfall. o areas of high runoff collection. - Avoid: o areas near septic systems. o areas with too many other drawing off aquifer. o areas of agricultural runoff. o impermeable rock. o areas with unconsolidated sediment. 12) Identify and describe three ways in which running water transports its load. Draw a cross - sectional diagram labeling these methods of sediment transport. 1) Suspended Load: floating silt, clay. 2) Disolved Load: ion solution. 3) Bed Load: bottom level rolling, jumping.

13) Draw a diagram that relates to and outlines the major operating processes in the Hydrologic cycle. Make sure to include all of the processes that were outlined in class. No, Answer. 14) Draw a bird’s eye view of a meandering stream. Label the point bars, cut banks, cut - off channels, and oxbow lakes. No, Answer. 15) Draw a diagram of and discuss the formation of river terraces. Which terraces would you expect to be characterized by the thickest, most mature soils? No, Answer. 16) How would the addition of an artif i cial base level (e.g. a Dam) affect the sediment transport of a stream? What sort of depositional and erosional patterns would you expect to see above and below the base level? What challenges may arise if that base level is then removed (short term? Long term?) -A dam or the artif i cial base would collect the sediment from the upstream erosion. -Dam will become chocked with sediments, and downstream has no soil, so it turns into a bedrock with no soil or vegetation. -Stream will wash out sediments to base level

20) Would earthquakes of similar magnitude and depth in different regions of the Earth cause approximately the same levels of damage necessarily? In your explanation, include both geologic and human - induced factors that may affect the levels of damage. No, it will not have the same levels of damage. Geologic Factors: waves move faster on a solid rock, and would be felt greatly. Human Factors: How close is the human to the epicenter, and is the earthquake hitting a city or a small town or village, would determine the damage amount caused. 21) What is the difference between the intensity and the magnitude of an earthquake? How do we measure these two things? Intensity is the “shaking” felt on the surface during an earthquake, and causes the most damage, and that is measured using the Mercalli scale based on 12 points. Magnitude is the amount of energy released during an earthquake. And is measured using a scale based on 10 points called the Richter scale. Saturated Zone The water table Gaining Stream Losing Stream Recharge Hydraulic

Gradient Springs Aquatard Well Cone of Depression Artesian well Aquifer depletion Land subsidence Groundwater contamination Hot spring Geyser Caverns Speliothems Travertine Karst topography Sinkholes Fault Focus Hydrologic Cycle Inf i ltration Runoff Evaporation Transpiration Global Water Rill Gully Drainage Divide Watershed Erosion Transportation Deposition Velocity Gradient Discharge Dissolved load Suspended load Bed load Saltataion Settling Velocity Braided Streams Meandering Streams Point Bar Cut Bank Base Level F l ood Plain Incised Meanders River Terraces Delta Natural Levee Alluvial Fan Fault Focus Epicenter Elastic Rebound Aftershocks Foreshocks Fault Creep San Andreas Fault *