geology of Colorado final

Dr. Vince Matthews

-author of our textbook -former state geologist of Utah

In the Colorado national Monument, a major unconformity exists between the Precambrian rocks (1.4 billion years old) and the triassic chicle formation (200 million years old). the hiatus represented by this gap is?

1,200 million years

Scientific method sequence

1. Construct a Hypothesis. 2.Test Your Hypothesis by Doing an Experiment. 3.Analyze Your Data and Draw a Conclusion. 4.Communicate Your Results.

The correct sequence of foliated metamorphic rocks that will form as time passes as heat and pressure are applied to shale?

1. slate 2. phyllite 3. schist 4.gneiss

to create a sedimentary rock, what is the correct sequence?

1. weathering 2. transportation 3. deposition 4. Lithification

the oldest rocks in Colorado are approximately _______ old.

2.7 billion years

How old are the earth and the solar system?

4.6 billion years

based on the atomic number how many naturally occurring elements are on the periodic table?

92

James hutton

Considered the father of modern geology

Denver is located on the western edge of the_______ physiographic province

Great Plains

Lithosphere

Most massive component of the earth (greatest volume and weight)

the plate-tectonic formation of the supercontinent called _______ was the trigger for creation of the ancestral Rocky Mountains

Pangaea

You are driving on interstate 70 over the front Range near the Eisenhower tunnel and your car spiders to a stop. As you wait for help to arrive you start looking at rocks in the nearby road cut which of the following will you observe?

Precambrian metamorphic and igneous rocks

which of the following statements best summarizes Colorados history during phase 2 (Cambrian-mississippian periods)?

The seas came in and the seas went out

what is required for contact metamorphism to happen

a magma body cooling at depth

if sedimentary rocks are deformed into a "sag" shaped fold (cross sectional view) the structure is called:

a syncline

if sedimentary rocks are deformed into an "arch" shaped fold (cross-sectional view) the structure is called:

an anticline

igneous rock type (magma type) that is created by partial melting of oceanic crust in a subduction zone

andesite

this partially molten layer of igneous rock underlies the lithosphere

asthenosphere

the largest igneous pluton is called a ______

batholith

which of the following is not a physiographic province in Colorado

cascade mountains

rock salt (halite)

chemical sedimentary rock

grand junction is located in the ________ physiographic province

colorado plateau

The last time the area now known as Colorado was flooded by ocean water was?

cretaceous period (phase 4)

from the surface of the earth downward to the center, the earths internal zones are:

crust, mantle, outer core, inner core

Numerous Paleo graphic maps were shown during Prof. Coles lectures. The geologist/artist who constructed these maps is__________

dr. ron Blakey, recently retired from northern Arizona university

Geologic eras have longer time durations (more years in them)than geologic eons true or false

false

The pliocene is a geologic period true or false

false

We are currently living in the mesozoic era true or false

false

extrusive igneous rocks have large crystals and intrusive igneous rocks have small crystals true or false

false

mineraloids have well-defined crystalline structure true or false

false

there are 3 types of strain (deformation): elastic, plastic, spastic true or false

false

phyllite

foliated metamorphic rock

what is not a basic type of heat transfer

gravity

Precambrian includes the following time units

hadean, archaen, and Proterozoic

what chemical element is diamond composed of?

halite

the energy that drives the "tectonics engine" (plate movement) comes from:

heat, which comes from radioactive decay of uranium, thorium, and potassium, plus hat left over from the earths formation

what oxide mineral has a rusty color

hematite

the driving force behind the formation of sediment at the surface of the earth

hydrologic cycle

rhyolite belongs to this rock group

igneous

concept of superposition

in a stack of undeformed sedimentary rocks, the oldest layer will be at the bottom

andesite

intermediate volcanic rock

the earths core is thought to be composed of mainly _____

iron and nickel

If we could use a time machine to visit the grand junction Area during late phase 3 (jurassic) when the wind gate Sandstone was being deposited, we would see:

large migrating sand dunes

the crystallization of what forms igneous rocks

magma

during contact metamorphism a limestone becomes a __________

marble

gneiss belongs to this rock group

metamorphic

heat, pressure, and chemical alteration of a preexisting rock in the subsurface are required to form this group of rocks

metamorphic

by definition, the rocks below a nonconformity consist of:

metamorphic and/or igneous rocks

muscovite

mica mineral

a spectacular fold called a______ can be seen in the sedimentary rocks along the front of Colorado national monument

monocline

regarding quantitative(numerical) age dates for precambrian igneous rocks in Colorado, what is the correct statement

none of the above

the footwall block moving up with respect to the hanging wall block

normal fault

igneous rock with a glassy texture

obsidian

term used to define a period of mountain building in the geologic past

orogeny

Pennsylvanian

period in the Paleozoic era

triassic

period in the mesozoic era

When did glaciation significantly impact Colorado?

phase 6

Academic disciplines that are major components of geology

physics, astrology, and astronomy

an igneous rock that has both large and small crystals is said to have a ______ texture

porphyritic

argon-40 is the radioactive decay product (daughter) of __________

potassium-40

contact metamorphism of sandstone will produce a ____

quartzite

the hanging wall block moving up with respect to the footwall block

reverse fault

The giant phase 6 "crack" (divergent plate boundary) in Colorado is called the:

rio grande rift

chemical and physical weathering at the earths surface are required to form this rock group

sedimentary

limestone and sandstone belong to this rock group

sedimentary

the orogeny took place in Utah, Arizona, and Nevada

sevier

summarize the occurrence of silurian sedimentary rocks

silurian sedimentary rocks are are only found in diatremes of north-central Colorado

biochemical sedimentary rock composed of sea shells

skeletal limestone

the largest physiographic province in Colorado is :

southern rocky mountain

where is the new ocean crust created?

spreading ridges at divergent plate boundaries

the time required for one half of the radioactive parent atoms to decay to their stable daughter atoms is called:

the half life

describe the velocity at which tectonic plates move

the move at about the same rate that you fingernails grow(inches per year)

Define Uniformitarianism

the present is the key to the past

Geochronology

the scientific study of time as it applies to the earth

What are two sedimentary rock units that are in the preCambrian age?

the uinta mountain and uncompahgre groups

The assigned video was produced by geologists and graphic artist from where?

the university of Colorado boulder

Phanerozoic

the youngest geologic eons

Geologic periods have longer time durations (more years in them) than geologic eons true or false

true

The boundary between the mesozoic and Cenozoic eras is 65.5 million years ago true or false

true

an arkosic sandstone has more than 25 percent feldspar grains true or false

true

igneous dikes cut across the layering found in the sedimentary rocks true or false

true

silicate minerals that contain iron such as biotite are usually dark grey to black true or false

true

the Miocene is a geologic epoch true or false

true

the most common rock-forming mineral in earths crust is quartz True or false

true

toadstool(mushroom) shaped intrusive igneous bodies (plutons) are called laccoliths. True or false

true

volcanic cinders, ash, and bombard called "pyroclastic'' true or false

true

peridotite

ultramafic igneous rock

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

if an igneous dike cross-cuts a sandstone bed, the dike is ______ the sandstone

younger than