Intro to Oceanography Test #2 (Chap3-5)

If one follows the Hawaiian Archipelago and Emperor Chain of islands and seamounts, it extends all the way from _____ still using just south of the Big Island all the way to _____ Seamount near the Aleutian Trench far in the Northwestern Pacific.

Loihi, Meiji

What is the most dominant and notable feature of the Atlantic Ocean basin?

Mid-Ocean Ridge

The largest geographical feature or features on the planet are ____

Mid-Ocean Ridges

As continents move on their plates, an area with little or no tectonic activity is called _____.

Passive margin or trailing edge

T/F - "Hydrogenous sediments" are produced in seawater by chemical processes where dissolved minerals precipitate out of the water and sink to the bottom. These "hydrogenous sediments" include phosphorites, manganese nodules, and salt deposits."

True

T/F - "Sonar" stands for "Sound Navigation and Ranging" and is used to find things such as fish, whales, and other objects in the water by directing a beam of sound pulses through the water and measuring the time it takes for the sounds to come back.

True

T/F - Because of hydrogen (H) bonds, water has a high heat capacity and resists temperature change by heating up and cooling more slowly than most other substances.

True

T/F - Coral reefs are important resources for people and the natural environment because they form substantial land masses and provide protection from storm waves, they attack tourists which provides for jobs and other economic benefits, and they provide important food resources and marine life habitat.

True

T/F - Evaporation and precipitation seem to play the largest roles in determining seawater salinity around the globe with lower salinity levels associated with the wet equatorial regions and cool rainy mid latitudes.

True

T/F - Frozen water molecules are more spaces out and less dense than liquid water molecules because the hydrogen bonds lock into a stable structure as compared to constantly breaking and reforming in their liquid phase.

True

T/F - In cold climates, salt can be extracted from seawater by freezing and refreezing seawater. When seawater freezes, only the freshwater freezes and the salt or salty water is mostly left behind. By removing the ice and heating the salty brine, the remaining water can be evaporated and the salt then collected.

True

T/F - In the late 1970s, Bob Ballard and other researchers from Woods Hole Oceanographic Institute started to discover large hydrothermal vents of hot mineral rich waters 2,000-5,000meters (6500-8000feet) below the surface on the Galapagos Rift off the coast of South America. Around these vents they also found large communities of never before seen undersea animals thriving on mineral rich waters and surviving completely without light at the bottom of the oceans along areas of sea-floor spreading.

True

T/F - Rift zones like the Red Sea and Great Rift Valley in Africa occur where upwelling of hot mantle rock heats the base of the lithosphere, causing it to thin, stretch, and split as new crustal material intrudes into the crack or rift

True

T/F - So far from what scientists know about these new deep-sea hydrothermal vent ecosystems is that the organisms are full of or feed on specialized bacteria that derive their energy from the sulfides and/or methane, in what is known as chemosynthesis, that is seeping and flowing from the hot water vents and/or cold seeps on the deep sea floor.

True

T/F - Submarine canyons are steep-sided, deep, v-shaped, canyons that sometimes extend up, into, and across the continental shelf and are thought to have been formed by rivers during lower sea levels and/or by fast moving flows or avalanches of mud, sand, and water called turbidity currents.

True

T/F - The San Andreas Fault that runs most of the length to California in the western United States is an example of a transform fault where two plates are sliding in opposite directions past one another

True

T/F - The mountain ranges under the sea are longer, the valley floors are wider, and the canyons are often deeper than those found on land.

True

T/F - The youngest of the "Main Hawaiian islands" is the Big Island of Hawaii while Kauai and Niihau are the oldest. The Northwestern or leeward Hawaiian islands are even older still and begin with Nihoa and Necker being the youngest of the Northwestern Hawaiian islands. As one continues up the chain, the islands and reefs become older until one reaches Midway and Kure atolls, the oldest and last of the islands. After Midway and Kure, the chain finally disappears underwater at what is called the Darwin Point. The Emperor Chain of Seamounts continue from there as older and older submerged volcanoes and guyots until they finally disappear and get recycled in the Japan-Kuril Trench.

True

A later development in coral reef formation most commonly found across the oceanic islands when the island begins to erode, sink, or subside away, leaving a lagoon between the land and the reef is called a ____.

Barrier reef

The hydrogen atoms of a water molecule are bonded to the oxygen atom by _____ whereas neighboring water molecules are held to each other by _____ bonds.

Covalent bonds, hydrogen

Explosive, composite type volcanoes associated with volcanic island arcs or continental mountain ranges are usually associated with ____

Deep sea trenches and convergent plate boundaries

"Siliceous oozes" are made up of the silica remains of small plants and animals consisting primarily of ______.

Diatoms and radiolarians

"Biogenous oozes" are made up of the calcium carbonate and silica remains of small plants and animals consisting primarily of ___.

Diatoms, foraminifera, radiolarians, pteropods, and coccolithophores

Water's polarity and ability to form bonds with other water molecules is critical to _____.

Evaporative cooling of skin surfaces, the movement of water from the roots of a tree to its leaves, milder temperatures of coastal regions when compared to inland areas, and the ability of certain insects to walk on the surface of water.

Sometimes during volcanic activity, thin slivers or channels of magma intrude into the cracks and slowly harden under the ground. The slow crystalization leads to much harder and denser rock called _____. This type of rock is waterproof and important in holding groundwater. Because it is harder than the surrounding rock it often also makes up the mountain ridges while the less durable surrounding rock erodes away.

Dike rock

T/F - The point in time where corals are on top of an old volcanic seamount can no longer keep up with the rate of subsidence and disappear or drown under the sea surface is called the "Evans Point" named after your infamous professor who devised this theory of coral reef development.

False, it is referred to as the Darwin Point.

T/F - Saltwater is less dense than freshwater because things tend to float more in saltwater as compared to freshwater

False, seawater is denser than freshwater.

T/F The Aleutian Trench is an example of a divergent plate boundary

False, the Aleutian Trench is formed along a convergent plate boundary.

T/F - The Mid-Atlantic Ridge system is an example of a convergent plate boundary

False, the Mid-Atlantic Ridge system is an example of a divergent plate boundary.

The Hawaiian islands and Emperor Seamounts are a series of oceanic volcanic islands and undersea seamounts that formed one-by-one over a molten _____ on the seafloor and have been carried northwestward across the Pacific Ocean by a process known as _____

Hot spot, plate tectonics

Sediments are carried to the oceans by water, wind, ice, and gravity. Fine particles tend to settle out in quiet bays and estuaries or further offshore. Accumulation rates for deep-sea sediments is _____ per 1000 years. Although these rates are extremely slow, sediment layers of ___ have accumulated on the deep-sea floor.

0.5-1.0cm (0.2-0.4in), 500-600m

Seawater absorbs 60% of the sunlight in the first meter and NO sunlight penetrates below _____ meters.

1,000 meters

The spreading rates of the plates are anywhere from _____ per year and tend to be ____ along the gentler East Pacific Rise as compared to other oceanic ridges.

1-20cm (0.4-8 inches), faster

What part of the undersea landscape is between 4000-6000meters (13,000-20,000feet) deep and covers more of the Earth's surface (30%) than all of the exposed continents combined?

Abyssal plains

In ocean-continental collisions, the thin, dense oceanic crust is driven underneath the thick, low density continental crust. As this crust is driven down and recycled, the heated up mixture of granite, basalt, sediments, and water rises to the surface where it often erupts explosively in a series or chain of continental volcanoes. Which of the following is an example or are examples of an ocean-continental collision?

Andes and Cascade Mountains

Most reef building corals are actually colonies of many feeding mouths called polyps which look like sea anemones. Reef building corals require clear, unpolluted, shallow, tropical, warm water. Reef building corals are unique in that they _____.

Are animals but have a symbiotic relationship with single called algae.

The whole region of the sea floor that is closest to the land or shore is called the ___.

Continental margin

The region of the sea floor that begins to rise off of the deep sea floor is called the ____.

Continental rise

T/F - Seawater absorbs all wavelengths of light except the visible light but of the wavelengths that do not penetrate the seawater, the short wavelengths at the blue end of the spectrum are absorbed the most rapidly.

False, the long wavelengths are quickly absorbed and the shorter, blue-green part of the spectrum penetrate to deeper depths.

T/F - Pelagic sediment are coastal sediments usually coming from the land that tend to deposit on the continental shelf and sometimes down the continental slope.

False. Those characteristics fit neritic sediments.

Initial coral reef development growing along the edge of an island or continental land area and are commonly found along coastlines in the Hawaiian islands is called a _____.

Fringing reef

Sound travels _____ and/but ____ water than in air.

Further, faster

In ocean-ocean collisions, the older, thicker, high density oceanic crust is driven underneath the thinner, low density oceanic crust. As the crust goes down and is recycled, the heated mixture of rock, sediments, and water rises toward the Earth's surface. This tectonic activity often leads to explosive, composite type volcanoes that often form a chain of volcanic islands or what is called a "volcanic island arc". Which of the following is an example or are examples of where there is an ocean-ocean collision?

Indonesia, Japan, Philippines

Desalination is the process used to extract freshwater from saltwater. What is NOT necessarily the most economical ($) but is the most rapidly growing form of desalination technology?

Reverse Osmosis

Coral death and disturbance is caused by natural and human disturbances. Natural disturbances on coral reefs occur from storm waves and stream runoff, competition for space by other animals, and predation such as feeding by the crown-of-thorns sea stars. Disturbances that are caused or increased by human activities occur from ____.

Sewage and other pollutants, sedimentation and fresh water flooding, as well as anchor damage and destructive fishing practices.

Water is the only common substance on Earth that naturally exists in all three states: solid, liquid, and gas. Water is held together by covalent bonds where the partners ______ electrons; in an ionic bond like salt (NaCl), the partners _____ electrons.

Share, give or take away

The ________ is an area under the sea about 1000m (3,300ft) where the combination of salinity, water temperature, and pressure cause the water to have a specific density where sound travels at a minimum sound velocity (speed) and sounds can become trapped and travel for great distances.

Sofar channel

Water is a versatile _______ and easily forms many types of solutions because the polar water molecules dissolve or break apart molecules into their individual positively or negatively charged _____.

Solvent, Ions

The oxygen atoms of each water (h2o) molecule ____.

are more electronegative than the hydrogen atoms

Reef building corals can reproduce by ____.

asexual reproduction by budding or cloning, asexual reproduction by fragmentation, sexual reproduction by production of eggs and sperm, sexual reproduction by planulae production