OCE1001 Midterm

The method that is most frequently used to investigate sediment and rock layers of the sea floor is:

sound waves

mid-ocean ridge

spreading center

seafloor spreading

spreading center

island arc

subduction zone

trench

subduction zone

Beach sand is usually well-sorted.

true

Black smokers are hydrothermal vents that discharge superheated water with high concentrations of metal sulfides

true

Fast-moving spreading ridges tend to be more gently sloped than slow-moving ridges

true

Radiolarian oozes form near the equator.

true

Radiometric dating is used to determine the ages of rocks.

true

Tektites are glassy rock fragments of cosmic origin.

true

Underwater avalanches of muddy water mixed with rocks and debris are:

turbidity currents

Continental-continental convergent plate boundaries produce what typical characteristic?

uplifted mountain ranges

The most likely origin of most of the Earth's oceans indicated by current scientific knowledge that was due to:

volcanic outgassing that released water vapor

Black smokers are hydrothermal vents that discharge superheated water with high concentrations of metal sulfides

white smokers

The book The History of Ocean Basins, which contained the idea of seafloor spreading was written by geologist

Harry Hess

Why is Iceland warmer than Greenland?

Iceland is over a mantle plume

Which of the following sediments contain at least 30% of the hard remains of calcareous-secreting organisms?

calcareous ooze

Why is free oxygen in our atmosphere so important to the development and maintenance to life on Earth?

can form ozone and block some UV radiation

The separation of the Earth into layers while it was molten was the result of the

differing densities of the elements that make up the Earth

The Hawaiian Islands-Emperor Seamount Chain was formed:

formed when the Pacific plate moved across a hotspot.

Sediment produced because of chemical reactions in seawater are called

hydrogenous

What two locations could have life began?

hydrothermal vents and hot springs

A tentative, testable statement about the general nature of phenomenon is called a/an

hypothesis

Coral reefs:

include atolls, barrier, and fringing reefs.

Earth's SOLID iron-nickel layer

inner core

Magellan

led voyage that first circumnavigated the globe

Sediment that begins as rocks on continents or islands is called

lithogenous

Turbidite deposits are an example of which type of sediment?

lithogenous

Earth's plates that are involved in plate tectonic motion

lithosphere

The correct order of marine provinces from the coast to the mid-ocean ridge is:

shelf, slope, rise, abyssal plain.

With respect to mid-ocean ridges, transform faults are:

perpendicular to the ridge axis.

The number of organisms present in the surface water above the ocean floor is called

productivity

Which of the following sediments are produced in areas of high primary productivity?

radiolarian & diatom

Distinguish between an ocean and a sea

A sea is usually smaller and shallower than an ocean, composed of salt water, somewhat enclosed by land, and is directly connected to the world ocean.

The first person to advance the idea of mobile continents or continental drift was

Alfred Wegener

What are the names of the four principle oceans(plus an additional ocean) on Earth?

Antarctic, Arctic, Indian, Pacific and Southern Oceans

Compare and contrast neritic and pelagic sediment deposits.

Neritic deposits are found near shore, while pelagic deposits are found in deep ocean. Neritic deposits cover about one quarter of the ocean floor, while pelagic deposits cover the rest. Neritic deposits often consist of coarse lithogenous material and pelagic deposits frequently have biogenous ooze and fine lithogenous clay.

Describe the formation of the magnetic patterns in rocks on the seafloor.

Rocks were first magnetized in normal orientation, then they were magnetized in reverse orientation, now they are once again magnetized in normal orientation. This pattern created the stripes on each side of the mid-ocean ridge

What is one of the most important organisms that changed the atmosphere in Earth's early history?

Stromatolites

Distinguish between a fracture zone and a transform fault.

Transform fault is a seismically active area that offsets the access of a mid-ocean ridge. A fracture zone is seismically inactive area that shows evidence of past transform fault activity.

The most gradual change in slope in the ocean can be found at the:

abyssal plain

The most likely place to find abundant manganese nodules is on the:

abyssal plain far from a continent.

All of the following provide evidence for continental drift except:

age of selected continental rocks

What does the nebular hypothesis suggest?

all bodies in the solar system formed from an enormous gas cloud.

Oceanic-continental convergent plate boundaries produce which of the following characteristic?

andesitic volcanoes

Earth's plastic layer, which flows when a gradual force is applied to it

asthenosphere

Earth's primordial atmosphere most likely included

carbon dioxide, water vapor, sulfur dioxide, and methane

Calcite dissolves more readily in seawater that is ________ in temperature and ________ in pressure.

colder; higher

Which of the following statements regarding oceanic and continental crust is TRUE?

continental crust is thicker and less dense than oceanic crust

All of the following are features associated with active plate margins except:

continental rise

The San Andreas Fault is considered a

continental transform fault

Sediments with an extraterrestrial origin are called:

cosmogenous

Passive continental margins are characterized by all of the following except:

deep-sea trenches.

The dissolution of the thick tests of foraminifers below the CCD is an example of the ________ of biogenous sediment.

destruction

All of the following are lithogenous sediments except:

diatom ooze.

The mid-Atlantic Ridge is an example of a

divergent boundary

lava pillow rocks are formed at which tectonic settings

divergent plate boundary

All continents fit together with the least number of overlaps and gaps when the continents are matched along

edge of the continental shelf

Vikings

established temporary settlement in North America

Seamounts form from ancient tablemounts

false

The Earth formed around 2 billion years ago

false

The deepest portions of the ocean are part of the relatively narrow features called submarine canyons.

false

A very important way to increase the settling rate of fine particles in the open ocean is via

fecal pellets

Eratosthenes

first determination of Earth's circumference

The type of marine sediment that forms the thickest deposits world-wide is:

neritic coarse lithogenous sediment deposits.

The most rapid change in slope in the ocean is found at the

oceanic trench

Earth's LIQUID iron-nickel layer

outer core

Vine and Matthews determined that new ocean floor was being produced at ocean ridges by examining:

the magnetic pattern on the seafloor.

Plate tectonics and evolution, which are held with a high degree of confidence because of rigorous testing and verification, are examples of

theories

Satellites are used to map the ocean floor because:

they are unaffected by surface weather. they can cover areas where ships have not produced surveys. they can "see" large areas of the seafloor at one time. the shape of the ocean surface itself reflects large features on the seafloor below.