Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
5 geologic principles
|
1. Original Horizontality
2. Stratigraphic superposition 3. Unconformities 4. Cross-cutting 5. Inclusions |
|
disconformity
|
unconformity between parallel starta or lave flows. most are very irregular surfaces, and piences of the underlying rock are often included in the strata above them.
|
|
angular unconformity
|
unconformity between nonparallel strata
|
|
nonconformity
|
unconformity gormed when stratified sedimentary rocks are deposited on eroded igneous or metamorphic rock
|
|
Unconformity
|
rock surface that represents a gap in the geologic record
|
|
Conformities
|
rocks on both sides of these planar features fomred in a continual sequence
|
|
Modes of preservation
|
1.preservation without alteration (frozen, mummified, entrapment- liquid)
2.preservation with alteration (prevalent mode of preservation: permineralization, replacement, carbonization, recrystallization) 3.Casts and Molds 4.Trace fossils |
|
Premineralization
|
ie- petrified wood- water and chemicals can go through
|
|
Carbonization
|
occur when plant debris or soft-bodies animals die and are buried. remains are decompressed and the volatile constituents are released, leaving a thin carbon silhouette behind.
|
|
Recrystallization
|
occures to creat a fossil when the substances that comprise the original organism (shell and bone) are converted to a more stable substance. ie- conversion of aragonite, a less stable form of calciium carbonate into calcite, a more stable from which occurs in same shell fish
|
|
Biodiversity
|
examination of the fossil record indicates that as organisms evolved the number of species increased.
|
|
Phyletic gradualism
|
hypothesis involving gradual changes in organisms over a long period of time and involving numerous generations
|
|
Punctuated equilibrium
|
no chnage occurs for extended periods and then, due to some sudden environmental change, a species must evolve rapidly to adjust to the new conditions
|
|
fossil assemblage
|
group of preserved organisms that cohabited a specific place at the same time
|
|
geologic map
|
topographic map with added info about the location and orientation of rock units and structures present in the area.
|
|
cross section
|
topographic profile with added info about the rock units and structures, depicted with the smae colores and symbols used in the geologic map
|
|
quaternary map
|
graphic representation of the distribution and identity of unconsolidated sediments which were deposited during the quaternary period
|
|
surficial map
|
combination of both the geologic and quaternary maps and shows the surface material whether it is bedrock or sediment
|
|
stratigraphy
|
study of the rock layers within the earth
|