Ocean Lab Final

Question 1

In a bathymetry map, contours connect lines of equal__

Answer 1

depth

Question 2

In a bathymetry map, in what direction would a ridge be pointing?

Answer 2

Downhill

Question 3

If there were a rapid change in elevation on a bathymetric map, how would the contours be spaced?

Answer 3

Close together

Question 4

On a map, the vertical scale is 2 cm/km, while the horizontal scale is 1 cm/10 km. What is the vertical exaggeration?

Answer 4

Vertical scale = 2 cm/km
Horizontal scale = 0.1 cm/ km
Vertical scale/Horizontal scale = 2/0.1 = 20

Question 5

What underwater feature is shown in the bathymetry map (circles that have greater numbers as they go inward)?

Answer 5

Underwater valley

Question 6

A floating object will displace its ___ in fluid.

Answer 6

Weight

Question 7

A ____ margin is typically located adjacent to a plate boundary.

Answer 7

Pacific/active

Question 8

What are the major chemical layers of the Earth?

Answer 8

Crust, mantle, core

Question 9

What type of rock typically composes the oceanic crust? The continental?

Answer 9

Basalt, granite

Question 10

Why are the crests of mid-ocean ridges higher than the surrounding seafloor?

Answer 10

They are younger and therefore warmer.

Question 11

Mid-ocean ridges are an example of this kind of plate boundary.

Answer 11

Divergent

Question 12

The Himalayas are consequences of THIS kind of plate boundary? Be specific

Answer 12

Continent-Continent convergence

Question 13

Which process ultimately destroys lithospheric material

Answer 13

Subduction

Question 14

You are trying to find the spreading rate along a mid-ocean ridge. You determine that the age of oceanic crust 400 km away from the ridge is 15 million years old. What is the spreading rate in cm/yr?

Answer 14

400 km = 40,000,000 cm

40,000,000/15,000,000 = 2.67 cm/yr

Question 15

In which direction is the plate moving, given that the youngest volcano is North-east?

Answer 15

South-west

Question 16

A manganese nodule is an example of what kind of sediment?

Answer 16

Chemogenic (hydrogenous) sediment.

Question 17

Which type of sediment dissolves below the CCS?

Answer 17

Calcareous Oozes

Question 18

What is the following sediment’s sorting classification (circles of many different sizes)?

Answer 18

Poorly sorted

Question 19

In terms of latitude, where is the CCD the deepest?

Answer 19

Warmer, less acidic water at LOWER latitudes

Question 20

When chalk (CaCo3) is exposed to acid (HCl), it fizzes. Name two of the three products of this reaction.

Answer 20

CaCl2, CO2, H2O

Question 21

Nama a process that can decrease the salinity of seawater.

Answer 21

Precipitation or glacier melt

Question 22

Name one consequence of hydrogen bonding in water.

Answer 22

High latent heat, high heat capacity, high melting point, high boiling point, less dense as solid, etc.

Question 23

At what latitudes are the highest amounts of surface water dissolved CO2 observed? Why?

Answer 23

High latitudes/ the poles. Because CO2 solubility is higher in cold water

Question 24

Give the formula for residence time. What units does residence time have?

Answer 24

T[units of time] = amount of a given element dissolved in the ocean/the flux of the element in or out of the ocean

Question 25

These ions act as a buffer in the ocean, keeping seawater from becoming too acidic or too basic.

Answer 25

Bicarbonate (HCO3-)

Question 26

What is the name of the region of rapid density change in the ocean?

Answer 26

Pycnocline

Question 27

What is the general name of the type of current that flows south on the left of the Pacific Ocean?

Answer 27

Western Boundary Current

Question 28

Name both regions of deep water discussed in lab.

Answer 28

North Atlantic Deep Water (NADW), and Antarctic Bottom Water (AABW)

Question 29

The net motion of water at a 90 degree angle to the prevailing wind direction is known as:

Answer 29

Ekman transport

Question 30

Name the methods of intermediate water formation.

Answer 30

1) Convergence of surface waters in subpolar gyres, causing dense water formation that sinks along isopycnals. 2) Warm, saline water flowing into Atlantic from the Mediterranean

Question 31

Name examples of phytoplankton, and zooplankton.

Answer 31

Phytoplankton: dinoflagellates, coccolithophores, cyanobacteria, diatoms. Zooplankton: copepods, krill, radiolarians, forams.

Question 32

Name examples of limiting nutrients.

Answer 32

Nitrogen, Phosphorous, Silica

Question 33

Name examples of macroplankton.

Answer 33

Krill, Pteropods, Gelatinous Plankton (Jellyfish)

Question 34

What are the three trophic groups?

Answer 34

Producers (autotroph), consumer (heterotroph), and decomposers (seprotroph)

Question 35

Define Euphotic, Dysphotic, Aphotic in terms of the amount of photosynthesis that occurs.

Answer 35

Euphotic: region from surface to critical depth where photosynthesis dominates. Dysphotic: photosynthesis no longer dominant but still takes place. Aphotic: completely dark, no photosynthesis.

Question 36

Periwinkle snails inhabit which tidal zones?

Answer 36

Splash zone to high tide zone

Question 37

Name ways intertidal organisms have adapted to dessication.

Answer 37

Large shell volume to hold water (periwinkle snail), closing up body cavity when tide goes down (mussels/barnacles), secreting mucus (anemone), moves to tidepools (sea urching, sea star), gill changers (crab)

Question 38

How does the large limpet deal with intruders in its space?

Answer 38

It bulldozes other organisms off the rock

Question 39

Why can red algae inhabit deep water environments?

Answer 39

They are better at absorbing blue light, which penetrates deeper in the ocean than other wavelengths

Question 40

What purpose does a kelp's pneumatocyst serve?

Answer 40

They are filled with gas and provide a buoyant upward force to keep the kelp upright

Question 41

What is the name of the wind pattern that drive equatorial currents?

Answer 41

Trade winds

Question 42

In ocean drilling expedition, you pick a site that has a low biological productivity and is far from the edges of any continents, islands or glaciers. What type of sediment do you expect to find at the seafloor?

Answer 42

Red (abyssal) clay

Question 43

Where would there be coastal upwelling

Answer 43

Peru (humbholdt) current

Question 44

How many times larger is the H+ concentration in lemon juice (pH = 2) that in black coffee (pH = 5)?

Answer 44

pH is a logarithmic scale so each step is a 10x difference. Lemon juice has 1,000x H+ than black coffee.

Question 45

Locate NADW and AABW on the T-S plot.

Answer 45

Picture not show, but AABW = D, NADW = C. (AABW has most dense, and coldest water).

Question 46

You have a million dollars due to a lucrative career as a geoscientist. How would you write this dollar amount in scientific notation?

Answer 46

$10^6

Question 47

There are approximately 3.1x10^4 undergraduates at UCLA. How would you write this in standard numeric form?

Answer 47

31,000

Question 48

You measure the salinity of a lagoon and find it to be 42.5 o/oo. How would you express this value in percent?

Answer 48

4.25%

Question 49

You have a yard that is 10mx10m. What is the area in square kilometers?

Answer 49

1 m = 0.001 km; 10 m = 0.01 km | 0.01 km * 0.01 km = 0.0001 sq km (10^-4)

Question 50

You have a piece of basalt (density 3.0 g/cm^3) but don't have a scale. Instead you put it into a beaker filled with water to see how much water it displaces. The rock displaces 4 mL. What is the mass of this rock?

Answer 50

m = d*v 4 mL = 4 cm^3 3.0 g/cm^3*4 cm^3 = 12 g