2: Earth Materials and Processes Flashcards
are formed from mineral grains
Rocks
Assembly of ____________ are not random; they are the result of the rock-forming process
mineral grains
formed by crystallization; composed of several kinds of minerals
Igneous rocks
composed of one kind of mineral
Sedimentary rocks
made up of one or more silicate units
Rocks
possess a crystalline structure
Minerals
Classified according to chemical composition and atomic structure
Minerals
structure based on silicate units.
Silicate minerals
Sedimentary rocks
clastic, chemical, and biogenic
Three types of grains
coarse, medium, and fine
Two types of weathering
physical (mechanical disaggregation) and chemical (Chemical decomposition)
the process of breaking down
Weathering
formed from “clasts”
Clastic rocks
formed from the evaporation of water
Chemical
contain fragments or fossils
Biogenic
Formed from igneous rocks which have undergone mechanical and physical stress
Metamorphic Rocks
occurs when the rocks are in their solid state
Metamorphism
between igneous and metamorphic is marked by the melting point of the rock
Transition
two types of metamorphism
Contact metamorphism
Regional metamorphism
broken rock
Erosion
movement
Transportation
deposited in a new location
Deposition
ice, wind, snow, and water (or even gravity alone)
Geomorphic agents
Exogenic Process
Erosion
Transportation
Deposition
Geomorphic agents
Uses heat from within the earth, Cause earthquakes, metamorphism, volcanic activity, formation of troughs and oceans
Endogenic Process
Endogenic Process is also called?
hypogene processes
form of wave motion that is transmitted through the surface of the earth
Earthquakes
gives rise to oceans, mountains, ridges; called distrophism when it results in building up
Tectonic Movements
matter is transported to the surface of the earth and then erupted; magmatic matter is effused to the surface, otherwise they are called intrusives or plutons
Volcanism
movement of the continents
Plate Tectonics
proposed by Wegener; movement of tectonic plates
Continental Drift Theory
The result of forces strong enough to move ocean sediments thousands of meters above sea level; Changes in volume/shape
Deformation
bend in the rock in response to compressive forces
Fold
caused by internal stresses in the rock that cause fractures
Fault
are key indicators of seafloor spreading
Polarity changes
seafloor moves away from ridges
Seafloor spreading
_________ rises up from fractures, cools on seafloor, causing formation of new seafloor
Basaltic magma
able to place events in their proper order, but unable to precisely identify the number of years
Relative dating
based on the decay of radioactive elements
Absolute dating
