6,8,10 Flashcards
What mineral particles are the dominant coloring agents in reddish, brownish and yellowish soils
Dust sizes grains of iron oxides
Which term describes soil formed by weathering of the underlying bedrock
Residual
What portion of an angular, fracture bounded granitic block shows the highest rate of weathering?
The edges and corners
Which two factors speed up rates of chemical rxn and weathering in rocks and soils?
Warm temps, very moist
Clay minerals formed from gabbro or diorite bedrock illustrate which kind of weathering
Chemical
In terrain with steep hill slopes, which crop and cultivation technique will minimize soil erosion
Apples; land between trees is planted in grass and not cultivated
Which of the following best describes the dust bowl
Areas of severe wind erosion on the Great Plains, 1930s
Under similar warm, moist climatic conditions, why would basalt and gabbro generally have higher chemical weathering rates then rhyolite and granite
The ferromagnesian minerals in the gabbro and basalt are subject to oxidation and chemical breakdown
Which term best describes an accumulation of angular rock fragments at the base of a steep, bedrock slope or cliff
Talus slope
Which of the following best describes the process eluviation
Removal of very fine sizes silt and clay particles from the A and E horizons
In which setting would regional metamorphism be most likely
At great depths in the crust where two continents are colliding
Amphibole is a foliated metamorphic rock composed principally of hornblende and plagioclase. How does it form?
By regional metamorphism of volcanic rocks such as andesite and basalt
What foliated, metamorphic is texturally intermediate between slate and schist
Phyllite
What is the major source of heat for contact metamorphism
Heat from nearby magma body
What platy, parallel, mineral grains are the most visual aspect of foliated metamorphic rocks
Micas
What term describes the zones of contact metamorphism surrounding an intrusive magma body
Aureole
Which of the folllowing forms at the highest grade of regional metamorphism
Schist
Which of the following lists the rocks in order of increasing grain size and increasing grade of metamorphism
Slate, Phyllite, schist
Which of the following statements concerning slate is not true
Has abundant, coarse grained mica
T or f: partial melting is an important process in the formation of migmatites
True
___ is typically formed by metamorphism of a sandstone
Quartzite
Calcite is the main mineral constituent of the sedimentary rock limestone and the metamorphic rock marble
True
A graben is characterized by
Hanging wall block that has moved down between two normal faults
A Horst is
An uplifted block bounded by two normal faults
The michigan geologic map show older, Paleozoic strata( in roughly circular patterns) surrounding the cores area of Pennsylvania rocks,. What is this structure?
Basin
a ____ fault has little or no vertical movements of the two blocks
Strike slip
A reverse fault is one which
The hanging wall block has moved up relative to the footwall block along an insulated inclined fault
A sync line is __
Fold in which the strata dip toward the axis
A ___ is a defined, recognizable, mapable, rock unit with a known age
Formation
Brittle deformation would be favored over plastic deformation in which of the following conditions
Cooler temps
The mountains and valleys of the basin and range province of the western untied states formed in response to
Tensionsal stress and normal fault movements
Which one of the following best describes the geology of the black hills region in South Dakota
An elongate dome cored by Proterozoic igneous and metamorphic rocks
Which one of the following is true for anticlines but not synclines
The seeker strata are buckled upward along the fold axis
__ are the products of horizontally directed, Tensionsal stresses
Normal faults
Along oblique slip faults, not blocks have horizontal and vertical components of movement
True
The oldest sedentary rock strata are exposed along the axial parts of deeply eroded anticlines
True
The Navajo and Dakota sandstones are
Mesozoic, sedimentary rock formation in Utah, Colorado, and neighboring states
Normal faults form in response to horizontal , Tensional stresses that stretch or elongate the rocks
True
The great Rift Valley of east Africa is characterized by ___
Mainly normal faulting as east Africa begins to fragment
