ESC1000 EXAM 3
What is the source of natural carbon-14?
Cosmic ray collisions and neutron-capture involving atmospheric nitrogen
Which of the following is the best measure of the wetness or dryness of a region?
Difference between annual precipitation and evaporation potential
Which of the following denotes the divisions of the geologic time scale in correct order of decreasing lengths of time beginning with the longest time interval and ending with the shortest?
Eon, era, period, and epoch
Which feature represents a former meltwater channel or tunnel in glacial ice that was filled with sand and gravel?
Esker
In what zone of the ocean does photosynthesis occur?
Euphotic
What is the typical cross-valley profile of canyons and valleys eroded and deepened by alpine or valley glaciers?
U-shaped
What is another name for a typhoon?
Hurricane
Which of the following is an erosional feature specifically produced by alpine glaciation?
U-shaped valley
Which of the following is formed from the abrasion of rocks by windblown sand?
Ventifacts
Which one of the following statements concerning rock weathering is true?
Warm temperatures and high soil moisture accelerate chemical weathering
When does a deep-water wave become a shallow-water wave?
When the wavelength is about twice the water depth
Which of the following statements concerning dry lands is FALSE?
Wind is the dominant agent of erosion and sediment transport
Subduction of oceanic lithosphere at the trenches can act like a bulldozer to produce ________.
an accretionary wedge
How are sand grains transported by the wind?
by saltation in the first few meters above the land surface
Which one of the following is determined by the angle of repose for dry sand?
Inclination angle of a dune slip face
What term describes the area where the land and ocean meet and overlap?
Intertidal zone
Which one of the following features forms when stagnant, glacial ice melts after being buried by drift?
Kettle
What fundamental concept states that, "in a horizontal sequence of conformable sedimentary strata, each higher bed is younger than the bed below it"?
Law of superposition
What is the final stable breakdown product of the radioactive isotopes uranium-238, uranium-235, and thorium-232?
Lead
What type of deposit consists of glacial rock flour from blowing winds?
Loess
In what part of the global ocean do thermoclines best develop?
Low latitudes
Which of the following characteristics would a cT air mass exhibit?
MT
What type of moraine is formed by the merging of two lateral moraines at a junction of two valley glaciers?
Medial
"Black smokers" are associated with ________.
Mineral-rich waters oceanic ridges hot water *all of these*
Which two Paleozoic periods used in North America are combined into the Carboniferous period in Europe and elsewhere?
Mississippian and Pennsylvanian
What term describes animals capable of moving independently of the ocean currents by swimming or other means of propulsion?
Nekton
What zone exists seaward of the low-tide line?
Neritic zone
Who made the first clear statement of the law of superposition? When?
Nicolas Steno, 17th century
Assume that man's recorded history can be stretched back to 4600 years before the present. This is approximately what fraction of geologic time?
One millionth
Which of the following respond(s) to the Coriolis effect?
Only wind direction
In addition to the chemical weathering of rocks on the continents, where did the dissolved materials in seawater originate?
Outgassing of elements from Earth's interior
What depositional feature would logically be situated next to a large end moraine or a terminal moraine?
Outwash plain
Which of the following pairs of features are deposited by meltwater streams?
Outwash plains and valley trains
In what units is the proportion of dissolved substances in seawater expressed?
Parts per thousand (‰)
What term describes the open ocean at any depth where animals swim or float freely?
Pelagic
In which process of fossilization are the internal cavities and pores of the original organism filled with mineral matter?
Petrification or petrifaction
What term describes the layers of the ocean into which sunlight penetrates?
Photic
What is the official term that describes algae?
Phytoplankton
Which group of organisms includes algae and bacteria that drift with ocean currents?
Plankton
What is the name of the force that causes wind to blow?
Pressure gradient force
What term describes the amount of carbon fixed by organisms through the synthesis of organic matter that uses energy derived from solar radiation?
Primary productivity
What concept states that "ancient life forms succeeded each other in a definite, evolutionary pattern and the contained assemblage of fossils can determine the geologic age of the strata"?
Principle of faunal succession
What plane defines a rapid change in density with depth in the ocean?
Pycnocline
Which one of the following concerning desert lands is FALSE?
Running water has little effect on shaping the landscape
What term describes the total amount of solid material dissolved in water?
Salinity
What term refers to the "bouncing" mode of sand transport in a windstorm or stream?
Saltation
Which factors determine productivity in temperate oceans?
Seasons
Which of the following best describes the term glacial drift?
Sedimentary materials, outwash and till
Which of the following is often associated with a cirque basin in high, mountainous terrain?
Tarn lake
In what type of oceans would productivity be highest?
Temperate oceans
Where are rain shadow deserts common?
The dry valleys of eastern California and Nevada
What happened to create an unconformity?
The older strata below were eroded before the younger layers were laid down
Which of the following is an essential characteristic of an index fossil?
The organism only lived for a short period of geologic time over a broad area
Which of the following best characterizes an angular unconformity?
Tilted strata lie below the unconformity; bedding in younger strata above is parallel to the unconformity
The gently sloping submerged surface extending from the shoreline toward the deep ocean is termed the ________.
continental shelf
Which one of the following is not part of the continental margin?
continental trench
Manganese nodules are an example of ________.
hydrogenous sediment
Minerals that crystallize directly from seawater are examples of ________.
hydrogenous sediment
An echo sounder operates by measuring the time required for a ________
sound pulse travels from a ship to the seafloor and back
Sediments derived primarily from the products of weathering on the continents are called ________.
terrigenous sediment
What is the most abundant salt in seawater?
*NaCl* (Sodium chloride)
What is the age of Earth accepted by most scientists today?
4.6 billion years
Complex, invertebrate life forms are common as fossils beginning with marine strata of Cambrian age. How long ago did the Cambrian period begin?
542 million years
What is the maximum limit on carbon-14 dating?
70,000-75,000 years
Which one of the following describes a valley glacier that lengthens (extends its terminus downslope) over a period of many years?
Accumulation exceeds wastage
How would air flow if Earth did not rotate?
Air would move directly from high to low pressure.
The ________ Ocean has more extensive abyssal plains than the Pacific Ocean because it has fewer trenches to trap sediments moving down the continental slope
Atlantic
What mature desert landscape feature consists of coalesced alluvial fans?
Bajada
Which dune is crescent-shaped with its tips pointing downwind?
Barchan
Why do most marine animals live near the surface of the ocean?
Because of sunlight
What are inselbergs?
Bedrock hills in a highly eroded desert landscape
Visualize five horizontal, sedimentary strata exposed in a cliff or canyon wall identified by consecutive numbers, 1 being the lowest bed and 5 being the highest. Which of the following statements concerning the strata are true?
Beds 1 and 3 are older than bed 4
Between which latitudes do most dry lands lie?
Between 20 and 30 degrees north and south of the equator
The percent of remaining parent isotope in a radioactive decay process is 40 percent. How many half-lives have elapsed since the material was 100 percent parent atoms?
Between one and two
What is the mass of all living organisms on Earth called?
Biomass
What factors influence density in seawater?
Both temperature and salinity
What is each feeding stage in the food chain called?
Trophic level
Which of the following is not a very long-lived, radioactive isotope?
C-14
Which process occurs when a glacier enters the sea?
Calving
What erosional features are produced at the heads of valley/alpine glaciers?
Cirques
Which of the following processes involve(s) heat transfer between, within, or through a mass or substance?
Conduction, convection, and radiation
Which of the following investigative processes do geologists use to identify and match sedimentary strata and other rocks of the same ages in different areas?
Correlation
Submerged, flat-topped seamounts are known as guyots.
true
What is a deep-water wave?
A wave where the water depth exceeds one-half the wavelength
Which pair of terms describes the circumstances when salinity in the ocean would be highest?
High evaporation; low precipitation
What is standard sea level pressure in inches of mercury?
29.92 inches
What would the daily range of temperatures be if the maximum temperature for a particular day is 26°C and the minimum temperature is 14°C?
12°C
Which of the following describes a drumlin?
A smooth, tapering ridge of till formed and shaped beneath a continental ice sheet
What type of unconformity is an erosional contact between tilted, older strata below and horizontal, younger strata above?
An angular unconformity
Where is the world's largest ice sheet currently located?
Antarctica
When and where does a sea breeze originate and blow?
During the day; blows toward the land
When and where does a land breeze originate and blow?
During the evening; blows toward the water
Where is the world's second-largest continental ice sheet?
Greenland
Which of the choices below is an irregular, usually thin till layer laid down by a retreating glacier?
Ground moraine
What term refers to the nearly vertical cliff left alongside a U-shaped valley where a tributary glacier entered at a high position on the valley wall?
Hanging valley
The North Pole has a higher noon Sun angle than New York City on this date.
The North Pole will not have a higher noon Sun angle than New York City on any date.
Which of the following geologic observations would not bear directly on interpreting the sequence of geologic events in an area?
The feldspar and quartz content of a granite
Sandstone strata and a mass of granite are observed to be in contact. Which of the following statements is correct?
The granite is older if the sandstone contains pebbles of the granite.
In the names of geologic eras, what does the suffix "zoic" mean?
The suffix "zoic" means life (i.e., living things)
What plane defines a rapid change in temperature in the depths of the ocean?
Thermocline
