Term
|
Definition
| Make no more assumptions than needed. Often the simplest answer is more likely to be the right one. |
|
|
Term
| Basic Steps In Scientific Method |
|
Definition
1. Make Observation
2. Invent Hypothesis to explain
3. Test Hypothesis --> Theory
4. Test Theory --> Law |
|
|
Term
| What are the Four Spheres? |
|
Definition
1. Biosphere
2. Geosphere
3. Hydrosphere
4. Atmosphere |
|
|
Term
| What drives Earth's processes? |
|
Definition
|
|
Term
| How do we tell geologic time and why is geologic time important for geologic processes? |
|
Definition
Absolute Time- putting a date/age on something (Using radioactive dating processes)
Relative- Age compared to other things (Steno’s Laws) |
|
|
Term
|
Definition
| Naturally occurring, inorganic crystalline solids with a definite chemical structure and internal structure |
|
|
Term
| What are rocks and how do we classify them? |
|
Definition
Material consisting of the aggregate of minerals like those making up the Earth's crust
Igneous, Sedimentary, and Metamorphic |
|
|
Term
| Which was the first NP and when was it ordained? |
|
Definition
| Yellow Stone NP, March 1, 1872 |
|
|
Term
| Difference between NP and NM |
|
Definition
| A NP is a large land area with a variety of attributes, while a NMs are landmarks, structures, and other objects of historic or scientific significance on government controlled prop. |
|
|
Term
| What are some of the reasons why protection, preservation, and maintenance of parks and monuments established early on was inefficient? |
|
Definition
| They viewed the NPs as “keeping it around so we can use it later”. |
|
|
Term
|
Definition
| Roosevelt 1906. The President, by executive order, can restrict the use of public land which is owned by the government in order to preserve historic sites. |
|
|
Term
| National Park Service Organic |
|
Definition
| Wilson 1916. Created the NPS. Protect from abuse in NP and NM. |
|
|
Term
| What are physiographic (geomorphic) provinces? How do you distinguish different provinces? |
|
Definition
| a geographic region with a specific geomorphology and often specific subsurface rock type or structural elements |
|
|
Term
| What is the ‘Rainshadow’ effect? How does it apply to the Colorado Plateau area? |
|
Definition
| is a dry region of land that is leeward of a mountain range or other geographic feature, with respect to prevailing wind direction. The mountains block the passage of rain-producing weather systems, casting a "shadow" of dryness behind them. Not quite sure how it “applies” to the Colorado Plateau area |
|
|
Term
| What kind of geologic contacts exist? How would you recognize them? |
|
Definition
1. Depositional Contact-
(a) Conformable- Layers deposited cleanly and evenly, leading to flat/even layering.
(b) Unconformable- Layers experienced weathering/erosion during deposition, leading to uneven layering
Intrusions
Faults |
|
|
Term
| Know relative dating principles and how to apply them. |
|
Definition
1. Principle of Superposition
2. Principle of Original Horizontality
3. Principle of Lateral Continuity
4. Cross-cutting Relationships
5. Unconformities
6. Inclusions
7. Fossil Correlation |
|
|
Term
|
Definition
| An unconformity is a buried erosion surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous Nonconformity- Two different rock types making a contact Disconformity- Same rock type making contact Angular Unconformity- Rocks contacting at a tilt or angle |
|
|
Term
How can you distinguish units resistant to erosion vs. those that erode easily?
(Apply it to Grand Canyon NP) |
|
Definition
| Depending on rock type (composition) and climate, rocks vary in their resistance to weathering. In the arid environment of the Grand Canyon, shales and other finer-grained sedimentary rocks weather easily and form talus slopes with lots of weathered material, whereas sandstones and limestones are more resistant and commonly form cliffs. |
|
|
Term
| What is meant by facies and the facies concept? |
|
Definition
Involves lateral rock changes which can he explained by changes in the depositional environment.
Thus, a facies is a distinct kind of rock for that area or environment. Each depositional environment grades laterally into other environments. We call this facies change when dealing with the rock record. |
|
|
Term
|
Definition
| Represent elevation. The closer the spacing the greater the slope of the increase in elevation. |
|
|
Term
| What are Index fossils? What are good characteristics of them? |
|
Definition
| Ideally a good one would be: common, easily preserved, lived for a short time before dying off, widespread/broad distribution, easily id’d. |
|
|
Term
|
Definition
| Protons, neutrons, and electrons |
|
|
Term
| How do we determine atomic numbers? How do we determine atomic weight? |
|
Definition
| The number of protons govern the atomic number, It is the weighted average of the masses of naturally-occurring isotopes. |
|
|
Term
| What are isotopes? What is meant by ‘stable’ vs. ‘unstable’ isotopes? |
|
Definition
| Elements of the same atomic number, but with a different atomic mass. (ie. neutrons) |
|
|
Term
| What is half-life? Why is the assumption that the half-life for a particular radiogenic isotope is a constant important? |
|
Definition
| How long it takes for an element to decay to wear the parent daughter ratio is 50/50. This is important for dating rocks and minerals. |
|
|
Term
| Why are we able to measure half-lives for isotopes with half-lives of several billion years? |
|
Definition
| Scientists analyzed the time for material to decay and theorized that it does so at a constant rate. |
|
|
Term
| What are common forms of radioactive decay? |
|
Definition
| Alpha Emission, Beta Emission, Electron Capture |
|
|
Term
| What rocks are best for radiometric dating? Which are worst? Why? |
|
Definition
| Igneous rocks are best because of the large number of minerals, Metamorphic is worst due to the changing, baking, and pressure changes associated with them. |
|
|
Term
|
Definition
| In order to use minerals for absolute dating, we have to assume that they are closed systems (i.e. no elements are added or removed). For certain minerals and certain dating techniques there are certain temperatures (blocking temperatures) at which the minerals are considered "closed" and the parent-daughter isotope ratio has not been altered at elevated temperatures. If the blocking temperature for a certain mineral or isotope system is exceeded, the parent or daughter isotopes can leave the mineral and the age that is derived from the would be either too old or too young |
|
|
Term
| • Why are some parent-daughter pairs easier to understand than others? In other words, why is U-Pb dating so much more complex than many other isotope pairs? What are some advantages of the U-Pb dating method? |
|
Definition
| U-Pb dating is extremely complex due to the length of time it takes to achieve Pb and the variety of different elements involved |
|
|
Term
| What are some general sources of uncertainty for absolute dating techniques? |
|
Definition
| It is not 100% sure that these isotopes decay at a constant rate, the release and addition of parent-daughter material over time. |
|
|
Term
|
Definition
| The theory that Earth’s crust is broken into sections (Plates) that are continually moving at very slow rates. The ways in which each plate interacts with its surrounding plates determines the geologic features of the region. This can be measured by dating/analyzing rocks at the MORs and the reversal in polarity |
|
|
Term
| Transgressions and Regressions |
|
Definition
| Inconsistencies in the deposition of a layer due to changing sea levels |
|
|
Term
| What would you see in the geologic record that documents either a transgression or regression? |
|
Definition
| Interfingering of adjacent layers |
|
|
Term
| What is the relationship between topography and horizontal geologic units? |
|
Definition
| As a general rule, areas of equal elevation represent similar layers of rock |
|
|
Term
| What is Stratigraphic correlation? How do you do it? What are Paleogeographic reconstructions? |
|
Definition
| Paleogeographic reconstructions use known information about the rocks in an area to paint a picture of what that area was like in the past, used often for determining changes in sea levels. |
|
|
Term
|
Definition
| deals with the relationship between burning fossil fuels and C14 concentrations |
|
|
Term
|
Definition
| states that since water that is deep below the surface does not react with the atmosphere readily, taking C14 readings from water will provide an inaccurate date |
|
|
