Term
| When did Pangea start to break up? |
|
Definition
|
|
Term
|
Definition
mountain building activity Jurassic-Cenozoic
Includes Nevadan, Sevier, and Laramide. |
|
|
Term
|
Definition
| Located in California; during the Triassic-Jurassic; granite intrusion obduction |
|
|
Term
|
Definition
| Located in Eastern Nevada and Western Utah; during the Jurassic-Cretaceous; Thrust belt |
|
|
Term
|
Definition
| Located in Eastern Utah and Western Colorado; during late Cretaceous-early Tertiary; uplifted blocks Anticlines. Formed present-day Rocky Mountains |
|
|
Term
|
Definition
| Caused by thrust faulting; when the crust gets filled in because of thrusts, you get more depressions. |
|
|
Term
| What is Sea-level the most influenced by? |
|
Definition
|
|
Term
|
Definition
| A major fault in the Sevier overthrust belt. It is exposed west of Las Vegas. |
|
|
Term
|
Definition
| Typically there are layers of clay, soot, ash, very rich. The Oridian anomoly there implies that it was from a meteorite; thought to be on the Yucatan peninsula. |
|
|
Term
| What percent of species have to be lost in order for there to be an extinction? |
|
Definition
| 50%. At the end of the Permian, we lost 90% of species on earth at the time. Greatest extinction ever. |
|
|
Term
| What are the rift valleys in Eastern NA from? |
|
Definition
| The rift valleys are caused by extension, specifically the break up of Pangaea. We see the remnants of Pangaea ripping apart in Eastern NA. |
|
|
Term
| What kind of changes occur because of rifting? |
|
Definition
| Changes in the ocean and climate |
|
|
Term
| When did a major shift occur towards cooler and drier climates? |
|
Definition
|
|
Term
| How long did the ice age in NA last? |
|
Definition
| It began 2.5 million years ago and ended 10,000 years ago. |
|
|
Term
|
Definition
| Glaciations cause depressions in the crust, but after the move out, the crust slowly comes back up. |
|
|
Term
| What kind of radiometric dating is used for recent events? |
|
Definition
|
|
Term
|
Definition
| Formed from magma (molten rock); hardens in or on the earth's crust. |
|
|
Term
| volcanic rocks or extrusive igneous rocks |
|
Definition
| those that formed at the surface |
|
|
Term
| plutonic rocks or intrusive igneous rocks |
|
Definition
| those that formed below the surface |
|
|
Term
|
Definition
happens when rapid cooling in a lava flow results in fine-grained texture and individual minerals are too small to see without magnification.
|
|
|
Term
|
Definition
| coarse-grained, the outcome of comparatively slow cooling that takes place in plutons. |
|
|
Term
|
Definition
| the cooling happened so rapidly that that the atoms in lava have too little time to form the 3-D frame-work of minerals. |
|
|
Term
|
Definition
In the rock cycle, weathering processes disintegrate rocks at or near the surface. Rocks are broken into smaller particles of gravel, silt, sand, and clay. These solid or dissolved materials are commonly transported elsewhere and deposited as sediment.
|
|
|
Term
|
Definition
| the geologic phenomenon of converting sediment into sedimentary rock. |
|
|
Term
| Detrital Sedimentary rocks |
|
Definition
| made of of detritus, that is, the solid particles such as gravel, sand, and mud derived from preexisting rocks. They have clasts and they include sandstone. |
|
|
Term
| Chemical Sedimentary Rocks. |
|
Definition
made up of minerals derived from materials in solution and extracted by either inorganic chemical processes or the activity of organisms.
|
|
|
Term
|
Definition
Any rock altered in the solid state from preexisting rocks by any combination of heat, pressure, and chemically active fluids. (sedimentary rocks followed by igneous rocks are most susceptible to metamorphism.) Metamorphic changes can be compositional (new minerals form) or textural (minerals become aligned) or both.
|
|
|
Term
|
Definition
| takes place when heat and chemical fluids from an igneous body alter adjacent rocks. |
|
|
Term
|
Definition
| takes place over large but elongated areas as the result of tremendous pressure, elevated temperatures, and fluid activity. |
|
|
Term
|
Definition
| much more restricted in its extent being confined to zones adjacent to faults (fractures along which rocks have moved) where high levels of differential pressure develop. |
|
|
Term
|
Definition
| Plate boundary along which adjacent plates slide past one another and crust is neither produced nor destroyed. |
|
|
Term
| Convergent Plate boundary |
|
Definition
| When two plates collide and one of the plates descends beneath the margin of the other plate and is subducted into the asthenosphere and eventually heated and incorporated into the mantle. |
|
|
Term
|
Definition
| when two oceanic plates converge, one is subducted beneath the other. The subducting plate bends downward to form the outer wall of an oceanic trench. |
|
|
Term
| What is the doppler effect? |
|
Definition
| The change in frequency of a sound wave caused by movement of its source relative to an observer. |
|
|
Term
| Oceanic-continental boundary |
|
Definition
| When an oceanic and continental plate converge, the denser oceanic plate is subducted under the continental plate along this boundary. The descending oceanic plate forms the outer wall of the oceanic trench. |
|
|
Term
| Continental-continental boundary |
|
Definition
| When continents collide, they are too dense for one to sink beneath the other. They are instead welded along a zone marking the former site of subduction. At this boundary, an interior mountain belt is formed. |
|
|
Term
|
Definition
| When you're actually looking at the elements to date (carbon-14). |
|
|
Term
|
Definition
| when you look at the rocks, sequences, and fossils to date. |
|
|
Term
|
Definition
| number of protons in the element |
|
|
Term
|
Definition
| have multiple broad, shallow channels in which mostly sheets of gravel and cross-bedded sand are deposited. Not well-sorted. |
|
|
Term
|
Definition
| deposition where river or stream enters the sea yields this body of sediment; mostly mudrocks and sandstone coarsening in upward sequence. |
|
|
Term
|
Definition
| The stable portion of the continent that has not been deformed. It includes the shield and stable platform. It is made up of metamorphic basement. |
|
|
Term
|
Definition
| The exposed portion of the craton; an example-the Canadian shield. |
|
|
Term
|
Definition
| the covered part of the shield. |
|
|
Term
|
Definition
| Mountain ranges, an area that is currently or recently being deformed by tectonics. |
|
|
Term
|
Definition
| No nucleus; first organisms had these and they consisted of archaea and bacteria. |
|
|
Term
|
Definition
| much larger than prokaryotes, have internal membrane-bound nucleus that contains chromosomes, and other internal structures not found in prokaryotes. |
|
|
Term
|
Definition
| Best preserved earliest form of life. A biogenic sedimentary structure, especially in limestone, produced by entrapment of sediment grains on sticky mats of photosynthesizing bacteria. Because of stromatolites free oxygen became available in our atmosphere. |
|
|
Term
|
Definition
| Six craton-wide sequences in NA. Each represents a transgression and regression. Defined as a large-scale lithographic unit representing a major transgressive-regressive cycle, bounded by craton-wide unconformities. |
|
|
Term
| What is the significance of the Burgess shale and how old is it? |
|
Definition
| Its a preservation of soft-bodied organisms. Its from the middle Cambrian |
|
|
Term
| Name some Cambrian biota. |
|
Definition
| Trilobites, brachiopods, archaeocyathids (cambrian reef-builders), and fish appeared too in this era. |
|
|
Term
| What are the layers of the earth? |
|
Definition
| Inner core (solid), outer core (liquid), mantle, and the crust. The crust is mad out of the lower mantle, asthenosphere, and upper mantle. The lithosphere consists of the upper mantle with the oceanic and continental crust. |
|
|
