Geo106 Module 11 Quizzes

What percentage of seawater, on average, consists of dissolved salt ions? a. 1.5% b. 3.5% c. 6.5% d. 5.5%

b. 3.5%

Coastal processes are of interest to geologists, but affect relatively few people because less than 10% of the world's population lives within 10 km of a sea coast. a. True b. False

b. False

Rip currents flow ________. a. directly toward the shoreline b. directly away from the shoreline c. parallel to the shoreline

b. directly away from the shoreline

Locally tidal reach will be greatest during ____________. a. full or last quarter moon b. full or first quarter moon c. full or new moon d. first quarter or last quarter moon

c. full or new moon

The dissolved cations sodium, potassium, and calcium are ____________.

introduced to the ocean by the inflow of rivers

Which statement is NOT true about living coral reefs?

Coral reefs are generally restricted to depths of 60 m below sea level.

____________ make up a majority of the ocean floor worldwide. a. Abyssal plains b. Continental shelves c. Continental rises d. Continental slopes

a. Abyssal plains

For the Earth as a whole, ocean water temperatures vary more than surface-air temperatures. a. False b. True

a. False

High tides occur simultaneously at all coastlines around the world, except for minor effects on bays. a. False b. True

a. False

The form and topography (depth profile) of the ocean floor is termed ____________. a. bathymetry b. aquitopography c. allocthony d. orogeny

a. bathymetry

As waves approach shore in shallow water their speed ____________. a. decreases b. increases

a. decreases

The width of a beach in winter is typically ____________ its width in summer. a. less than b. more than c. same

a. less than

Bioturbation is the ____________. a. mixing of the sediment by burrowing organisms b. formation of biochemical sedimentary rocks c. mixing of sediment by plankton d. generation of turbidity by sea creatures

a. mixing of the sediment by burrowing organisms

Longshore currents flow ____________. a. parallel to the shoreline b. directly away from the shoreline c. directly toward the shoreline

a. parallel to the shoreline

The most prominent force inducing tides on Earth is the ____________. a. Sun's gravitational pull b. Moon's gravitational pull c. electromagnetic attraction between Earth and the Sun d. gravitational attraction between ocean waters and the continents on Earth

b. Moon's gravitational pull

The density of seawater increases with ___________. a. increasing temperature and increasing salinity b. decreasing temperature and increasing salinity c. increasing temperature and decreasing salinity d. decreasing temperature and decreasing salinity

b. decreasing temperature and increasing salinity

If currents are largely directed toward shore, the area is likely to experience ____________. a. upwelling b. downwelling

b. downwelling

Because of wave refraction, erosion along an irregular coastline is ____________. a. even along the length of the coast; b. greatest along headlands c. greatest in bays

b. greatest along headlands

When the sea level rises, the ocean may invade a river valley, producing a nearshore body of water of mixed and variable salinity termed a(n) ____________. a. atoll b. lagoon c. estuary d. jetty

b. lagoon

The oldest oceanic crust is approximately ____________ years old. a. 50 thousand b. 4 billion c. 200 million d. 2.5 million

c. 200 million

The shallowest portions of ocean found along the margins of continents are the ____________. a. Abyssal plains b. Continental rises c. Continental shelves d. Continental slopes

c. Continental shelves

Which trench includes the world's deepest sea floor (more than 11 km below sea level)? a. Peru-Chile Trench b. Puerto Rican Trench c. Marianas Trench d. Kamchatka Trench

c. Marianas Trench

Major oceanic surface currents travel ____________. a. parallel to the prevailing direction in the region b. in direct opposition to prevailing winds as a result of the Coriolis effect c. at an angle to prevailing winds as a result of the Coriolis effect d. at an angle to prevailing winds as a result of the Doppler effect

c. at an angle to prevailing winds as a result of the Coriolis effect

The magnitude of tidal effect (lateral extent of the intertidal zone between low and high tides) is affected by the ____________. a. steepness of the intertidal beach b. position of the Sun c. bathymetry of the region d. A and C are correct

c. bathymetry of the region

Sand groins _______. a. have solved the problem of beach drift b. increase erosion rates in the region up current from the groin c. increase erosion in the region down current from the groin d. increase depositional rates in the region downcurrent from the groin

c. increase erosion in the region down current from the groin

Saline ocean water is ____________ than fresh water, and provides ___________ to objects floating in it. a. less dense; more buoyant b. less dense; less buoyant c. more dense; more buoyant d. more dense; less buoyant

c. more dense; more buoyancy

Waves ___________. a. reflected directly backward from the angle at which they approached the shoreline b. are reflected off the shoreline, but never refracted c. refract (bend) so as to impact the shore in a nearly parallel manner d. refract so as to impact the shore nearly perpendicular to the shoreline

c. refract (bend) so as to impact the shore in a nearly parallel manner

Compared to continental lithosphere, oceanic lithosphere is ____________. a. approximately the same thickness b. thicker c. thinner

c. thinner

Which portion of the sea floor is most steeply sloped? a. abyssal plains b. continental shelves c. continental rises d. continental slopes

d. continental slopes

Most of the igneous rocks within oceanic abyssal plains are ____________. a. covered by limestones made up of the fragments of large invertebrate shells b. covered by sand and gravel introduced by rivers at deltas c. exposed at the surface of the sea floor d. covered by clay and the skeletal remains of microplankton

d. covered by clay and the skeletal remains of microplankton

Which type of coastline would most likely contain estuaries or fjords? a. emergent coastline b. subductive coastline c. diergent coastline d. submergent coastline

d. submergent coastline

On a bathymetric map, contour lines connect points of equal ____________.

depth of the sea floor below sea level

A guyot is a(n) ____________.

flat-topped seamount