Geology test 1
In the Colorado National Monument, a major uncomformity exists between the precambrian rocks and the triassic chinle formations. The hiatus represented by this gap is
1,200 million years
The oldest rocks in Colorado are approximately __________ old
2.7 billion years
Igneous rock type that is created by partial melting of oceanic crust in a subduction zone
Andesite
What is not a physiographic province of Colorado?
Cascade mountains
Which of the following academic disciplines are major components of Geology?
Chemistry, Physics, and Biology
Grand Junction is located in the ______ physiographic province
Colorado Plateau
The last time the are now known as Colorado was flooded by ocean water
Cretaceous period (phase 4)
Numerous paleogeographic maps were shown during Prof. Cole's lectures. The geologist-artist who constructed these maps is
Dr. Ran Blakey, recently retired from Northern Arizona University
What isn't a basic type of heat transfer?
Gravity
Denver is located on the western edge of the _____ physiographic province
Great plains
Which of the following statements pertains to the concept of superposition?
In a stack of undeformed sedimentary rocks, the oldest layer will be at the bottom
If we could use a time machine to visit Grand Junction area during late phase 3 (jurassic) when the wingate sandstone was being deposited, we would see
Large migrating sand dunes
Term used to define a period of mountain building in the geologic past
Orogeny
When did glaciation significantly impact Colorado?
Phase 6
The rocks in nearby road cut by the Eisenhower tunnel
Precambrian metamorphic and igneous rocks
The giant phase 6 "crack" (divergent plate boundary) in Colorado is called
Rio Grande Rift
This orogeny took place in Utah, Arizona, and Nevada
Sevier
What statement summarizes the occurrence of silurian sedimentary rocks?
Silurian sedimentary rocks are only found in a diatremes of north central colorado
The largest physiographic province in Colorado is
Southern Rocky Mountains
Regarding quantitative (numerical) age dates for precambrian igneous rocks in colorado, what statement is correct
The dates are between 1.8 and 1.0 billion years ago
Uniformitarianism
The present is the key to the past
Which of the following statements best summarizes Colorado's history during Phase 2 (cambrian-mississippian periods)?
The seas came in and the seas went out
What statement is false?
There are 3 types of strain (deformation): elastic, plastic, splastic
Which statement describes the velocity at which tectonic plates move?
They move at about the same rate that your finger nails grow (inches per year)
When an igneous rock is dated by the uranium-lead or other radiometric method, the number (date) that is obtained indicates
When the magma cooled and solidified into rock
"Sag shaped
a syncline
If sedimentary rocks are deformed into an "arch" shaped fold (cross sectional view) the structure is called
an anticline
This partially molten layer of igneous rock underlies the lithosphere
asthenosphere
The assigned video was produced by geologists and graphic artists
at the University of Colorado Boulder
From the surface of the earth downward to the center, the earths internal zones are
crust, mantle, outer core, inner core
The energy that drives the "tectonic engine" (plate movement) comes from
heat from radioactive decay of uranium, thorium, and potassium, plus heat left over from the earths formation
The earths core is composed of what
iron and nickel
By definition, the rocks below a non-conformity consists of
metamorphic and/or igneous rocks
A spectacular fold called a __________ can be seen in the sedimentary rocks along the front of Colorado National Monument
monocline
The plate tectonic formation of the super-continent called _______ was the trigger for creation of the ancestral rocky mountains
pangaea
Argon-40 is the radioactive parent atoms to decay product (daughter) of ______
potassium -40
New oceanic crust is created here
spreading ridges at divergent plate boundaries
These 2 sedimentary rock units are precambrian in age
the Uinta Mountain and Uncompahgre groups
A normal fault is defined by
the foot wall block moving up with respect to the hanging wall block
The time required for one-half of the radioactive parent atoms to decay to their stable daughter atoms is called
the half life
A reverse fault is defined by
the hanging wall block moving up with respect to the foot wall block
If an igneous dike cross cuts a sandstone bed, the dike is _______ the sandstone
younger than