surface of erosion separating younger strata above from older strata below
Catastrophism _________
was a philosophy that was first expounded by the early Greeks
Consider the names of the eras in the geologic time scale. What is meant by "zoic"?
Life; living things
Which of the following geologic observations would not bear directly on working out the sequence of geologic events in an area?
the feldspar and quartz contents of a granite
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
The ______ is the idea or concept that ancient life forms succeeded each other in a definite, evolutionary pattern and that the contained assemblage of fossils can determine geologic ages of strata?
Principle of fossil succession
Which of the following is an essential characteristic of an index fossil?
The organism only lived for a short period of geologic time
By applying the law of superposition _____ dates can be determined
relative
About 88% of geologic time is represented by the time span called the _____.
Precambrian
What is the age of the Earth accepted by most scientists today?
4.5 billion years
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. How old are 1, 3 and 4 relative to each other?
Beds 1 and 3 are older than bed 4
A worm would stand a poor chance of being fossilized because...
worms have no hard parts
Which of the following gases was NOT part of Earth's original atmosphere?
oxygen
During the early Paleozic era, South America, Africa, Australia, Antarctica, India, and perhaps China comprised the vast southern continent of ______
Gondwanaland
Which type of bacteria thrived in environment that lack free oxygen?
anaerobic
Which era of geologic time spans about 88% of Earth's history?
Precambrian
Mammals became the dominant land animals during the ____ era.
Cenezoic
Due to a virtual absence of land plants and certain animals, fossil fuels are notably absent in ____ rocks.
Precambrian
The major source of free oxygen in the atmosphere is from ______
green plants
The process in which plants use light energy to synthesize food sugars from carbon dioxide is called _____.
photosynthesis
Each continents contains large "core areas" of Precambrian rocks referred to as ____
shields
By the close of the Paleozoic, all the continents had fused into the single super continent of _____
Pangaea
The most exonomically important resource in Cenozoic strata of the Gulf Coast is _______
petroleum
Which era is sometimes called the "age of dinosaurs"?
Mesozoic
It is thought that submarine canyons on the continental slope have been generated by _____
turbidity currents
Seamounts are ______
volcanoes that form on the ocean floor
Which of the following is associated with ocean ridges?
Rift zones
mountainous topography
volcanic structures
all of these
Sediments derived primarily from the products of weathering on the continents are called ______
terrigenous sediment
The gently sloping submerged surface extending from the shoreline toward the deep ocean is termed the _____.
continental shelf
An echo sounder operates by measuring the time required for a ______.
sound pulse travels from a ship to the seafloor and back
The oceans cover approximately ____% of Earth's surface.
70
The _____ Ocean is largest
Pacific
Concerning the distribution of land and water, which of the following statements is true?
The Southern Hemisphere has much more water surface than the Northern Hemisphere
"Black Smokers" are associate with ____-
oceanic ridges
mineral-rich waters
hot water
all of these
The total amount of solid material dissolved in water is known as ____
salinity
THe most abundant salt in seawater is _____
NaCl
Salinity in the ocean is highest in regions where ____ is high and ____ is low.
evaporation; precipitation
A rapid change in temperature with depth in the ocean is called the _______
thermocline
Density in seawater is determined by ______
temp and salinity
Most marine animals live near the surface of the ocean becuase of _____, which supports photosynthesis by marine algae that form the basis of the food chain.
sunlight
Organisms, such as algae and bacteria, that drift with ocean furrents are known as ____.
plankton
Animals capable of moving independently of the ocean currents, by swimming or other means of propulsion, are called _____.
nekton
Open ocean of any depth where animals swim or float freely is known as the ____ zone.
pelagic
In the food chain, each feeding stage is called a ____ level.
trophic
T or F
The upper part of the ocean into which sunlight pentrates is called the photic zone
true
T or F
Productivity in the oceans is highest in tropical regions
false
Which of the following is correct regarding a wave in the open ocean?
water particles move in an almost circular path
The movement of water within the surf zone that parallels the shore is termed _____.
long shore current
Which one of the following is a landfrom createdb by wave erosion?
sea arch
A sandbar that completely crosses a bay, sealeing it off from the open ocean is a _____.
sea stanck
tombolo
coastal barrier
none of these
A ridge of sand projecting into a bay and often having a hooked end is a _____
spit
Which of the following is a tidal current?
both flood and ebb tide
The energy that drives surface ocean currents such as the Gulf Stream comes from _____
prevailing winds
Because of the Coriolis effect, surface ocean currents are deflected to the ___ of their path of motion in the Northern Hemisphere.
right
Large estuaries are more common on a ____ coastline.
Submergent
T or F
Although the sun influences the tides, its effect is considerably less that the effect of the moon.
