(a) Agulhas Current, West Australia Current (b) Brazil - SCIN - 136 View Full Document This is the end of the preview. Sign up to access the rest of the document. Unformatted text preview: (a) Agulhas Current, West Australia Current (b) Brazil Current , Benguela Current (c) Canary Current, Gulf Stream (d) Kuroshio Current, California Current (e) Labrador Current, Humboldt Current E. Labrador Current, Humboldt Current During winter months, monsoon winds over the Indian Ocean __________. (a) flow from land to sea and are dry (b) flow from land to sea and are wet A. Flow from land to sea and are dry (c) flow from sea to land and are dry (d) flow from sea to land and are wet (e) the direction of airflow is unchanged but precipitation increases Thermohaline circulation patterns are caused by variations in ___________. (a) evaporation (b) precipitation (c) land runoff (d) heat exchange with the atmosphere (e) all of the above E. All of the above The densest water in ocean currents is the ___________.

(a) warmest and saltiest (b) coldest and saltiest (c) warmest and freshest (d) coldest and freshest B. Coldest and saltiestB.... Week 4 competetion of the Arctics American Public University In the Hayes expedition he kept going towards the furthest north pole because "the th Week 4 competetion of the Arctics What are the major currents in the world's oceans? - Quora Quora Surface currents make up only 8% of all water in the ocean. See list below. Some current like Peru current are also called by other names like Humboldt current. Meanwhile, deepwater current are the thermohaline circulation Alphabetical list: Great South Australian Coastal Upwelling System Guinea Current Three most important currents are Gulf stream, Kuroshio and Equatorial under current. There are other currents such as California current, west wind and east wind drifts in the south. 131 Views Written Oct 29 The best villain ever (in my opinion) - The Joker This was yesterday, since there was a Halloween party going on..

The makeup is supposed to look like the one Heath Ledger wore in The Dark Knight and the hairstyle is taken from the new Joker (Jared Leto) from Suicide Squad. So it's kind of a mixture of both jokers, which I personally like. Also had a few rings on fingers and a suite (which can't... JetStream MAX - An Online School for Weather: Major Ocean Currents South Atlantic Western Australia This image will help identify the top 25 of the world's wind driven ocean currents. To view each current individually, uncheck the "All Currents" box then toggle on/off each of the other currents. Currents indicated by the red color are considered "warm" currents as they transport warm water (and heat) toward the poles. The blue colored currents indicate the transport of cold water toward the equator. One set of currents that are not directly related to the wind are the "counter" currents. Like the name implies, these currents run counter to the prevailing wind direction but usually only in regions where the winds are weak. These currents are located along the equator and are a result of the water returning east after it was pushed west by the equatorial currents.

The reason for their motion "counter" (opposite) to the wind flow is because the northern and southern equatorial currents, pushed westward by the trade winds, pile up water in the western portion of each ocean basin. This results in a sea surface is about 0.5 meter (18 inches) higher in the western Pacific near Indonesia than it is in the eastern Pacific near South America. Because of the pile of water, gravity causes it to flow back eastward across the ocean basin in the area where the winds are weak, which is along the equator. The same is true for the coast of Antarctica as well with the East Wind Drift current. The Agulhas Current The average ship-drift derived surface velocity plot shows two major source regions for the Agulhas current: (1) from the Mozambique channel to the north and along the coast; and (2) from the east including a major contribution from the Madagascar current. The average SST image shows the Agulhas current bringing warm water poleward.

On the average, the Agulhas current retroflects and returns eastward with part of the flow recirculating in the counter-clockwise flowing subtropical gyre and part of the flow feeding the Antarctic Circumpolar Current. There is also a component of the Agulhas current that feeds the Benguela current and advects relatively warm and salty water into the South Atlantic as part of the Global "conveyor belt" circulation. Click here for example plots of seasonal averages . The Agulhas Current is the western boundary current of the South Indian Ocean. It flows down the east coast of Africa from 27°S to 40°S (Gordon, 1985). The source water at its northern end is derived from Mozambique channel eddies (de Ruijter et al., 2002) and the East Madagascar Current, but the greatest source of water is recirculation in the southwest Indian Ocean sub-gyre (Gordon, 1985; Stramma and Lutjeharms, 1997). There are temporal and latitudinal variations in the depth, path, and transport of the current.

From synoptic measurements, the Agulhas Current was found to extend throughout the water column in March, but in a later survey during June it was limited to the upper 2300 m (Donohue et al., 2000). Its depth tends to increase with latitude to offset the increase in planetary vorticity (Boebel et al., 1998). In addition, there is seasonal oscillation in the sea surface height variability of the Agulhas Current. It is at a maximum during the austral summer and at a minimum during the austral winter. The magnitude of this seasonal change is about 30% of the mean value (Matano et al., 1998). The dominant mode of variability of the Agulhas Current is in the form of natal pulses (Bryden et al., 2003). These are large solitary meanders containing a cold-core cyclone on the inshore side of the current (Lutjeharms and Roberts, 1988). Natal pulses occur about 6 times per year and propagate downstream at approximately 10 km/day (Lutjeharms et al., 2003).

The passage of nearly all natal pulses is followed by the spawning of an Agulhas ring (Van Leeuwen et al., 2000). Like other western boundary currents, the Agulhas Current is quite fast. At the surface, it can reach maximum speeds of 200 cm s-1 (Boebel et al., 1998). Beal and Bryden (1999) examined the deep velocity structure by using Lowered Acoustic Doppler Current Profiles (LADCP) and found that their results were different from those of previous studies that used geostrophic estimates. Beal and Brydenfound that the level of no motion across the Agulhas Current displays a V-shaped pattern. They were also able to detect an Agulhas Undercurrent at 800 m depth. The undercurrent is directly beneath the surface core of the poleward flowing Agulhas Current, and it flows equatorward with maximum speeds near 30-40 cm s -1 (Beal and Bryden, 1999; Donohue et al., 2000).

As one of the major currents in the Southern Hemisphere, the Agulhas Current system transports large volumes of water. One of the earliest measurements of the geostrophic volume transport of this current came from Gordon (1985), who found it to be 67 Sv (1 Sv = 1 x 106 m3 s-1). Several years later, Toole and Warren obtained a much higher estimate 85 Sv. However, several researchers pointed out that the geostrophic reference level that Toole and Warren used did not resolve the counter-flowing Agulhas Undercurrent. Beal and Bryden (1999) found the geostrophic volume transport as referenced to LADCP to be 73 Sv, which was only 3% different from the direct LADCP transport estimate. Then, Donohue et al. (2000) attempted to refine previous transport calculations by removing barotropic tides and by estimating instrumental and sampling errors. The two LADCP sections that they used yielded a net southward transport of 78±3 and 76±2 Sv. The latest estimate comes from Bryden et al.

(2003) who find an average volume transport, calculated from year-long moored current meter measurements of 69.7±4.3 Sv. As the Agulhas Current reaches the southern tip of the continental shelf of Africa, it begins to turn toward the west. Once it reaches the Southern Ocean, the current retroflects, or turns back on itself, and flows eastward as the Agulhas Return Current (Quartly and Srokosz, 1993). The Agulhas Return Current flows eastward and exhibits a quasi-stationary meandering pattern of wavelength 500 km between 38° and 40° S. Its core width is about 70 km with an associated transport of 44±5 Sv in the upper 1000 m (Boebel et al., 2003). On average, the Agulhas Retroflection has a loop diameter of 340 km and can be found between 16°E and 20°E (Lutjeharms and van Ballegooyen, 1988).

Altimeter data suggest that during the austral winter months there is an early retroflection of the current near 25°E (Matano et al., 1998) and there is greater mesoscale variability (Quartly and Srokosz, 1992). However, satellite studies of the Agulhas Retroflection based on feature-tracking rather than area-averaging (Lutjeharms and van Ballegooyen, 1988; Goni et al., 1997; Quartly and Srokosz, 2002) find that "ring-shedding events" dominate the variability, which are found to be neither continuous, nor periodic. The retroflection gradually extends westward prior to ring-shedding and quickly retrogrades eastward after an Agulhas Ring is spawned. Upstream, the dominant mode of variability within the Agulhas Current is in the form of large, solitary meanders, known as Natal Pulses (Bryden et al., 2003).

There is evidence that these meanders may prompt ring-shedding as they propagate downstream and interact with the retroflection loop (Leeuwen et al., 2000). An interesting aspect of the Agulhas Retroflection is that it periodically sheds pinched-off anticyclonic rings 320 km in diameter at its westernmost extension. These rings enclose pools of relatively warm and saline Indian Ocean water whose temperature is more than 5°C warmer and and salinity 0.3 psu greater than South Atlantic surface water of similar density (Gordon, 1985). The rings keep their distinctive thermal characteristics as far west as 5°E and as far south as 46°S, and they drift into the South Atlantic at approximately 12 cm s -1 (Lutjeharms and van Ballegooyen, 1988). This warm-water link between the Atlantic and Indian oceans is likely to have a strong influence on global climate patterns (Gordon, 1985). Van Ballegooyen et al.

(1994) studied the Agulhas Retroflection region and counted 14 new rings over a 2-year period. They also found that the heat anomaly contained in a ring could be as much as 2.4 x 1020 J, and the salt anomaly could be as much as 13 x 1012 kg. Lutjeharms and Cooper (1996) went on to calculate that the heat flux into the South Atlantic could be 0.0075 PW per ring, and the estimated salt flux could be 13 x 1012 kg per ring. Although climatologically important exchange between the Atlantic and Indian Oceans occurs mostly via Agulhas rings, there are also Agulhas filaments that make a minor contribution when they occasionally escape into the South Atlantic. These filaments are present 56% of the time and are on average 50 km wide and 50 m deep. Each filament carries excess heat of about 3.5 x 10 19 J and excess salt amounting to about 1-5 x 1011 kg.

Since most of the heat is rapidly lost to the atmosphere, the main contribution to interbasin exchange by the filaments is a 3-9 x 10 12 kg annual salt flux (Lutjeharms and Cooper, 1996). Recent float and model experiments reveal that Agulhas Rings are as deep as 1200 m and salt and heat exchange at intermediate depths is important. They also show that the Agulhas retroflexion region not only spawns large (200 km) anti-cyclonic Agulhas Rings, but also smaller (120 km) cyclones (Boebel et al., 2003). The interaction of these cyclones and anti-cylcones results in vigorous mixing and stirring of Indian Ocean and Atlantic Ocean water masses to the northwest of the retroflexion within a region dubbed the "Cape Cauldron". References Beal, L.M. and H.L Bryden, 1999: The velocity and vorticity structure of the Agulhas Current at 32°S. Journal of Geophysical Research, 104, C3, 5151-5176.

Boebel, O., T. Rossby, J Lutjeharms, W. Zenk, and C. Barron, 2003: Path and variability of the Agulhas Return Current. Deep-Sea Research II, 50, 35-56. Boebel, O., J. Lutjeharms, C. Schmid, W. Zenk, T. Rossby, and C. Barron, 2003: The Cape Cauldron: a regime of turbulent inter-ocean exchange. Deep-Sea Research II, 50, 57-86. Boebel, O., C.D. Rae, S. Garzoli, J. Lutjeharms, P. Richardson, T. Rossby, C. Schmid and W. Zenk, 1998: Float experiment studies interocean exchanges at the tip of Africa. EOS, 79, 1, 1, 7-8. Bryden, H.L. and L.M.

Beal, 2001: Role of the Agulhas Current in Indian Ocean circulation and associated heat and freshwater fluxes. Deep-Sea Research Part I, 48, 8, 1821-1845. Bryden, H.L., L.M. Beal, and L.M. Duncan, 2003: Structure and transport of the Agulhas Current and its temporal variability. submitted to the Journal of Oceanography. Donohue, E.A., E. Firing and L. Beal, 2000: Comparison of the three velocity sections of the Agulhas Current and the Agulhas Undercurrent. Journal of Geophysical Research, 105, C12, 28585-28593. Gordon, A.L., 1985: Indian-Atlantic transfer of thermocline water at the Agulhas Retroflection. Science, 227, 1030-1033. Leeuwen, P. J., W. P. M. de Ruijter, and J. R. E.

Lutjeharms, 2000: Natal pulses and the formation of Agulhas Rings. J. Geophys. Res., 105, 6425-6436. Lutjeharms, J.R.E and R.C. van Ballegooyen, 1988: The Retroflection of the Agulhas Current. Journal of Physical Oceanography, 18, 11, 1570-1583. Lutjeharms, J.R.E. and J. Cooper, 1996: Interbasin leakage through Agulhas Current filaments. Deep-Sea Research Part I, 43, 2, 213-238. Lutjeharms, J.R.E., O. Boebel, and H.T. Rossby, 2003: Agulhas cyclones. Deep-Sea Research II, 50, 13-34. Lutjeharms, J.R.E., and H.R. Roberts, 1988: Tha Natal Pulse: an extreme transient on the Agulhas Current.

Journal of Geophysical Research, 93, 631-635. Matano, R.P., C.G. Simionato, W.P. Ruijter, P.J. van Leeuween, P.T. Strub, D.B. Chelton and M.G. Schlax, 1998: Seasonal variability in the Agulhas Retroflection region. Geophysical Research Letters, 25, 23, 4361-4364. Quartly, G.D. and M.A. Srokosz, 1993: Seasonal variations in the region of the Agulhas Retroflection: Studies with Geosat and FRAM. Journal of Physical Oceanography, 23, 2107-2124. de Ruijter, W.P.M., H. Ridderinkhof, J.R.E. Lutjeharms, M.W. Schouten, and C. Veth, 2002. Observations of the flow in the Mozambique Channel.

Geophysical Research Letters , 29, 140.1-140.3. Stramma, L. and J.R.E. Lutjeharms, 1997: The flow field of the subtropical gyre in the South Indian Ocean into the Southeast Atlantic Ocean: a case study. Journal of Geophysical Research, 99, 14053-14070. Toole, J.M. and B.A. Warren, 1993: A hydrographic section across the subtropical South Indian Ocean. Deep-Sea Research I, 40, 10, 1973-2019. Van Ballegooyen, R.C., M.L Grundlingh and J.R.E. Lutjeharms, 1994: Eddy fluxes of heat and salt from the southwest Indian Ocean into the southeast Atlantic Ocean: A case study. Journal of Geophysical Research, 99, 14053-14070. Van Leeuwen, P.J., W.P.M. de Ruijter, and J.R.E.

Lutjeharms, 2000: Natal pulses and the formation of Agulhas Rings. Journal of Geophysical Research, 105, 6425-6436. The Benguela Current The Benguela current as represented by the Mariano Global Surface Velocity Analysis (MGSVA). The Benguela Current is the eastern boundary current of the South Atlantic subtropical gyre. The Benguela Current flows through a strong, biologically productive upwelling region, and advects cool waters to the tropics. This water is warmed and is one of the source waters for the South Equatorial Current. Click here for example plots of seasonal averages . The Benguela Current is the eastern boundary current of the South Atlantic subtropical gyre (Peterson and Stramma 1991, Wedepohl et al. 2000). It begins as a northward flow off the Cape of Good Hope, where it skirts the western African coast equatorward until around 24°S-30°S. Here most of it separates from the coast as it bends toward the northwest.

However, two branches of the current do continue along the coast, and one of them joins the Angola Current at the Angola-Benguela front near 16°S (Wedepohl et al. 2000; see the description of the Angola Current for more information on the Angola-Benguela front). One of the earliest descriptions of the Benguela Current came from James Rennell. In 1832, he described what he called the South Atlantic Benguela Current as flowing north along the western coast of Africa until it reached the equator, where it turned sharply west to become the (South) Equatorial Current. He made a chart of the Atlantic Ocean, but it did not show the current running up to the equator; instead, it showed the current separating from the coast at around 30°S, much like in modern illustrations of the Benguela Current. Apparently Rennell did not discuss this depiction of the current because he would later suggest that cool waters at the equator were transported there by the Benguela Current from cold southern latitudes (Peterson et al. 1996). Modern observations and theory indicate that the cool equatorial waters are due to upwelling induced by divergent Ekman transport.

The sources of the Benguela Current include Indian and South Atlantic subtropical thermocline water; saline, low-oxygen tropical Atlantic water; and cooler, fresher subantarctic water. In the area between the continental shelf and Walvis Ridge it was found that 50% of the source water came from the central Atlantic, 25% came from the Indian Ocean, and 25% came from the Agulhas Current and the tropical Atlantic (Garzoli et al. 1996). The Benguela Current has a well-defined mean flow that is mostly confined near the continent and a more variable transient flow on its western side. The transient flow is dominated by large eddies shed from the Agulhas Retroflection. Barotropic and baroclinic components are equally important for the mean flow, while the variability is mostly barotropic (Garzoli et al. 1996). Conceding that the definition of the seaward boundary of the Benguela Current is ambiguous and variable, Shannon (1985) nevertheless observed that there is a well-developed oceanic front in the south. Shannon thus estimated that the Benguela Current was 200-300 km wide.

Wedepohl et al. (2000) found that in the south the current indeed has a width of 200 km, but as it flows northward it widens rapidly, becoming as wide as 750 km in the north. The generally weak current flow makes it difficult to precisely locate its seaward edge and strong seasonality in the wind-forcing causes estimates of mean speed and transport, based on in-situ measurements, that can vary by a factor of two. Shannon (1985) gathered all available information about surface speed from previous studies and calculated the mean speed of the Benguela Current to be 17 cm s-1. Wedepohl et al. (2000) found that the mean speeds of the current vary from <11 cm s-1 to a maximum of 23 cm s-1. Apparently the highest speeds occur in the south during summer and in the north during winter, a pattern that corresponds with seasonal wind fields. The prevailing winds are responsible for strong Ekman transport and the resulting coastal upwelling of cool, nutrient-rich water that stimulates primary productivity (Boyer et al. 2000, Skogen 1999).

There have been several varying estimates of the transport of the Benguela Current. Sverdrup et al. (1942) estimated it to be 18.7 Sv at 30°S relative to 1200 m; Fu (1981) calculated the geostrophic transport at 500 m across 32°S to be 20 Sv; Shannon (1985) obtained the value of 15 Sv; Stramma and Peterson (1989) found it to be 21 Sv at 32°S and 18 Sv at 30°S away from the coast; and Garzoli and Gordon (1996) concluded that it was 13 Sv on average. The value obtained by Garzoli and Gordon (1996) was lower than previous estimates because there is a strong variation of the flow that in a 16-month average results in a lower value. It had been widely thought that the avearge Benguela transport across 30°S is about 20-25 Sv.

However, these values were obtained during hydrographic cruises that only provided a snapshot of the actual flow (Garzoli et al. 1996). The amount of transport across the current is not very variable on a large scale. An analysis of three years of geostrophic transport data from a large-scale array showed that the transport did not change interannually by more than 20% . Greater variability is observed on smaller spatial scales and shorter time scales, especially if there are Agulhas rings nearby (Garzoli et al. 1997). As a complement to the BEST program (Benguela Source and Transport; Garzoli et al., 1996), and to directly measure the northward flow of intermediate water in the southeastern Atlantic, a new experiment, the Benguela Current Experiment, was conducted during 1997-1999 by P. L. Richardson and S. L. Garzoli.

Thirty RAFOS floats were launched in intermediate water at a nominal depth of 750 m across the full width of the Benguela Current near 30°S, across the Benguela Current Extension just upstream of the mid-Atlantic ridge near 7°W, and in three Agulhas rings. The float trajectories (Richardson and Garzoli, 2002) reveal an active, regional mesoscale eddy field consisting of cold-core cyclonic features and large, warm-core, anti-cyclonic Agulhas rings. The mean westward speed of the Benguela Current Extension intermediate water is 2 to 2.5 cm s-1. The boundaries of the Benguela Current Extension were clearly defined at 750 m; the Benguela Current Extension was bounded on the south by 35°S, and on the north by an eastward current located between 18°S and 21°S. Other recent float measurements suggest that this eastward current originates near the Trinidade Ridge, close to the western boundary, and extends across most of the South Atlantic, limiting the Benguela extension from flowing north of approximately 20°S.

The westward transport of the Benguela Current Extension is estimated to be 15 Sv. Roughly 1.5 Sv of this is transported by the approximately 3 Agulhas rings that cross the mid-Atlantic ridge each year. Geostrophic shear in the Benguela Current and its extension was very small (1-2 cm s-1), suggesting that this current is only weakly baroclinic. The total westward transport in the Benguela Current Extension above 1000 m and between 18°S-33°S is estimated to be 29 Sv. A noteworthy phenomenon that can be encountered in the Benguela Current system is the Benguela Niño. Like Pacific El Ninos, Benguela Niños are thought to be a result of anomalous atmospheric conditions in the western tropical Atlantic (Boyer et al. 2000). Every year there is a southward intrusion of warm Angolan water into the northern Benguela, but during a Benguela Niño the Angola-Benguela front is displaced south, causing the advection of warm, highly saline water as far as 25°S (Shannon et al. 1986, Boyer et al.

2000). Three Benguela Niños have been recorded. They occurred in 1934, 1963, and 1984. During the 1963 event temperatures off the coast of Namibia were 2-4°C higher than normal, and the pressure adjusted sea level was 4 cm above the mean. Although Benguela Niños do occur, they are less intense and less frequent than Pacific El Niños (Shannon et al. 1986). References Boyer, D., J. Cole, and C. Bartholome, 2000: Southwestern Africa: Northern Benguela Current region. Marine Pollution Bulletin, 41, 123-140. Fu, L.L., 1981: The general circulation and meridional heat transport of the subtropical South Atlantic determined by inverse methods. Journal of Physical Oceanography, 11, 1171-1193. Garzoli, S.L. and A.L. Gordon, 1996: Origins and variability of the Benguela Current.

Journal of Geophysical Research, 101, 897-906. Garzoli, S.L., A.L. Gordon, V. Kamenkovich, D. Pillsbury, and C.Duncombe-Rae, 1996: Variability and sources of the south eastern Atlantic circulation. Journal of Marine Research, 54, 1039-1071. Garzoli, S.L., G.J. Goni, A.J. Mariano, and D.B. Olson, 1997: Monitoring the upper southeastern Atlantic transports using altimeter data. Journal of Marine Research, 55, 453-481. Peterson, R.G. and L. Stramma, 1991: Upper-level circulation in the South Atlantic Ocean. Progress in Oceanography, 26, 1-73. Peterson, R.G., L. Stramma, and G. Kortum, 1996: Early concepts and charts of ocean circulation. Progress in Oceanography, 37, 1-115. Richardson, Phil .L., and Silvia L.

Garzoli, 2002: Characteristics of Intermediate Water Flow in the Benguela Current as measured with RAFOS floats. In press Deep Sea Research. ( ) Shannon, L.V. 1985. The Benguela Ecosystem, I., Evolution of the Benguela, physical features and processes. Oceanography and Marine Biology, 23, 105-182. Shannon, L.V., A.J. Boyd, G.B. Brundrit and J. Taunton-Clark, 1986: On the existence of an El Nino-type phenomenon in the Benguela system. Journal of Marine Research, 44, 495-520. Skogen, M.D., 1999: A biophysical model applied to the Benguela upwelling system. South African Journal of Marine Science, 21, 235-249. Stramma, L. and R.G. Peterson, 1989: Geostrophic transport in the Benguela Current region. Journal of Physical Oceanography, 19, 1440-1448.

Sverdrup, H.U., M.W. Johnson, and R.H. Fleming. The Oceans, 1087 pp., Prentice Hall, Englewood Cliffs, NJ. 1942. Wedepohl, P.M., J.R.E. Lurjeharms, and J.M. Meeuwis, 2000: Surface drift in the south-east Atlantic Ocean. South African Journal of Marine Science, 22, 71-79. Third MEA Test // Cramberry: Create & study flash cards online Front Back 1. Fig. 1 illustrates the surface currents of the global ocean. Which of these currents was named after a famous naturalist, i.e., a scientist (biologist-geologist) who discovered new volcanoes and hundreds of new species? Choose among the … [A] Kuroshio current … /B] Agulhas current … /C] Benguela current … /D] Humboldt current … /E] Canary current. /D] Humboldt current 4. Hundreds of millions of dollars are being spent on beach replenishment in North Carolina.

What is the source of most of this sand and what are the consequences of using that source of sand? Choose from among ....... [A] The sand is mostly quarried from coastal sandstone and this decreases the amount of sandstone available for construction near the beach. ........./B] The sand is quarried from crushed granite in the Piedmont and this sand is trucked to the coast, causing lots of motorists to lose windshields due to flying sand grains............/C] The sand is mostly pumped from offshore, producing dark beaches (due to admixed mud), and steeper offshore gradients, hence faster erosion. B] The sand is quarried from crushed granite in the Piedmont and this sand is trucked to the coast, causing lots of motorists to lose windshields due to flying sand grains 25. A geologic example of elastic behavior involves the transmission of earthquake energy from California to North Carolina. Sensitive instruments at NCSU can detect vibrations from earthquakes in California. From Los Angeles to Raleigh, this earthquake energy is transmitted elastically through about ... [A] 2200 km (1366 miles). …. /B] 2700 km (1677 miles).

… /C] 3600 km (2236 miles). …. /D] 4200 km (2608 miles). … /E] 4600 km (2857 miles). /C] 3600 km (2236 miles). 27. Fig. 5 illustrates a set of strike-and-dip measurements along the surface of a folded sedimentary bed. A strike-and-dip symbol records the orientation of any arbitrary plane in space. The orientation is given relative to that of the horizontal plane, i.e. the plane of the Earth's surface. Each strike-and-dip symbol has a number attached to it. The number which is associated with each strike-and-dip symbol is .... [A] the compass direction of any line within the arbitrary plane. .../B] the compass direction of the line within the arbitrary plane which lies closest to true north. .../C] the maximum angle between the arbitrary plane and the plane of the horizontal. .../D] the minimum angle between the arbitrary plane and the plane of the horizontal. .../C] the maximum angle between the arbitrary plane and the plane of the horizontal. 30.

Most of the motion along the San Andreas fault has been roughly horizontal and parallel to the fault plane. A fault with this type of motion is called a strike-slip fault. As one looks across a strike-slip fault plane, the motion of the opposite block is either toward the right or toward the left of the observer, as shown in Fig. 7. In the case of the San Andreas, the motion has mostly been toward the .. [A] left...... .../B] right. .../B] right. 34. Fig. 8 illustrates orthogonal views of a plunging fold. The plunge on this fold is about.. [A] 5o ...../B] 11 o ....../C] 21 o ... .../D] 70 o ..... .../E] 80 o ...../B] 11 o 37. Engineers are trained to predict whether fracture or ductile deformation will occur during the application of stress to a particular type of solid, e.g. the support pier of a skyscraper. Geologists make the same type of prediction for rocks deep within the Earth. Geologists generally predict that all rocks will exhibit at least minor folding and/or faulting if they lie deeper than ……….

[A] 10 cm……… /B] 100 cm………. /C] 100 m ……… /D] 1 km ………. /E] 10 km. E] 10 km 40. A continental shield is an assemblage of cratons. The largest shield in North America is the Canadian shield. Which of the following is the most common rock type in the Canadian shield? Choose among … [A] marble. .../B] shale. .../C] sandstone. .../D] granitic gneiss. D] granitic gneiss. 44. A line on the Earth's surface along which all points have the same inclination of magnetic domains is called a line of .... [A] magnetic latitude. ... /B] magnetic longitude… . /C] magnetic lineation… . /D] magnetic striation. [A] magnetic latitude 47. The magnetized stripes in Fig. 18 indicate that ... [A] plate velocity toward the right is roughly the same as toward the left. ... /B] plate velocity toward the right is roughly ten times as fast as toward the left.

.../C] the Earth's magnetic field is fluctuating much more rapidly at the moment than it did a couple of billion years ago. .../D] the Earth's magnetic field is fluctuating much less rapidly at the moment than it did a couple of billion years ago. A] plate velocity toward the right is roughly the same as toward the left 2. Like the moon, the Sun induces tides on Earth. The influence of the Sun is a little less than half that of the moon. As illustrated in Fig. 3, the Sun's influence … [A] constantly augments that of the moon. … /B] constantly detracts from that of the moon. … /C] seasonally augments or diminishes the lunar effect. /C] seasonally augments or diminishes the lunar effect. 11. Many types of structures have been built worldwide to protect beaches from erosion. Probably the most common of these is a slightly-submerged offshore barrier which is designed to induce the initiation of the surf zone farther from shore than it would occur naturally. This type of manmade barrier is called a ... ... /A) ballastmaker... /B) holdfast... /C) surfstarter... /D) breakwater... /E) barbreaker.

/D) breakwater 14. Depletion of ozone within the stratosphere by chlorofluorocarbons is a hazard to humans largely because it will probably lead to an increased incidence of skin cancer. In contrast, an augmentation of ozone at the Earth’s surface will probably lead to an increased incidence of .. [A] lung cancer …. /B) stomach cancer. .. /C) cholera. .. /D) meningitis. [A] lung cancer 23. Engineers are trained to predict whether fracture or ductile deformation will occur during the application of stress to a particular type of solid, e.g. the support pier of a skyscraper. Geologists make the same type of prediction for rocks deep within the Earth. Geologists generally predict that all rocks will exhibit at least minor folding and/or faulting if they lie deeper than ………. [A] 10 cm……… /B] 100 cm………. /C] 100 m ……… /D] 1 km ………. /E] 10 km /E] 10 km 24. Stress makes rocks bend and break. Geologists classify all of the following as types of stress.

The type of stress which created the Triassic Basin under Research Triangle Park was mostly tensional stress. The prime stress that produced the San Andreas Fault .. (A) also was tensional stress. .. (B) was uniformly-directed compressional stress .. (C) was differential compressional stress . .. (D) was shear stress (D) was shear stress 26. Sir Robert Hooke demonstrated that within the stress range of elastic behavior, strain is directly proportional to stress. However, at higher degrees of stress, strain .. [A] is inversely proportional to stress......./B] cannot be measured unambiguously......./C] does not exist......./D] increases at a higher rate than the stress which is inducing that strain. D] increases at a higher rate than the stress which is inducing that strain 43. After correcting for elevation and the volume of underlying rock, geophysicists still detect variations in gravity around the globe (Fig. 16). These variations are called residual anomalies. Lateral variation in corrected gravity measurements is primarily due to lateral variation in.. [A] rock temperature. .../B] rock density. .../C] rock ductility. .../D] poor calibration among instruments. .../B] rock density 1.

Surface currents in the ocean are driven by unequal heating of the Earth by the Sun. In the northern hemisphere, warm surface currents move northward along the western edges of both the Atlantic and Pacific Oceans. The Pacific current is called the Kuroshio and the Atlantic current is called the Gulf Stream. The origin of the name, Gulf Stream, is obvious. The name, "Kuroshio" comes from ... [A] the Philippine term for cloudy water. .../B] the Korean word for curry powder. .../C] the Japanese term for black tide. …/D] the Taiwanese word for curds in ship’s milk. .. /E] the Portuguese word for kinky ships. C] the Japanese term for black tide 9. As illustrated in Fig. 4, the salinity of polar seawater (at the sea surface) is lower than anywhere else in the ocean. This is primarily due to .. [A] the large rivers which discharge voluminous water in this area. .../B] the rapid flow of glaciers into the sea, and melting of the resultant icebergs. .../C] the sinking of salty seawater which has become denser due to cooling while flowing poleward.

.../D] the extremely high rate of rainfall in this area, higher than anywhere else on Earth. C] the sinking of salty seawater which has become denser due to cooling while flowing poleward 15. Ozone which occurs in the upper atmosphere, i.e. the stratosphere, is good for us because it helps to protect us from.. (A) cosmic rays …. /B) infrared radiation …. /C) radioactive radiation …. /D) ultraviolet radiation. D) ultraviolet radiation 17. Although the concentration of atmospheric carbon dioxide is low, it is greater than that of all of the following atmospheric gases except .. (A) argon.. .. /B) neon …. /C) methane …. /D) nitrous oxide .... /E) ozone. (A) argon 20. To mitigate against global warming due to anthropogenic gas emission, one may hope for a large volcano to erupt. Eruption of the volcano, Pinatubo, on the Philippines in June of 1991 lowered the world-average temperature by 0.5 o C to 1.0 o C for a few years. Immediate cooling was expected because Pinatubo emitted a large volume of fine-grained dust into the stratosphere.

This dust circled the globe within days and partially reflected sunlight. Along with dust, Pinatubo emitted gas which also impeded solar heating of the Earth. The crucial chemical element in this Earth-cooling gas was .. (A) sodium . .. /B) sulfur . .. /C) selenium . .. /D) cesium. B) sulfur 31. Stress obviously exists along the San Andreas Fault. For example, the rapid release of stress resulted in a magnitude-6 earthquake along the San Andreas, about half-way between Los Angeles and San Francisco, on Sept. 28, 2004. Of the following types of stress, the principal type of stress along the San Andreas (according to Plate Tectonic Theory) is … [A] tensional stress ........ /B] compressional stress ....... /C] shear stress. /C] shear stress. 28. Fig. 7 illustrates a pair of normal faults. Production of these normal faults could include all of the following types of stress at different times and places within the illustrated area. However, the one essential type of stress to produce this type of structure would be .... [A] compressional stress ....... /B] shear stress ....... /C] tensional stress. /C] tensional stress. 33.

The Rhine is a famous river in Germany that flows through a graben like that illustrated in Fig. 8. The graben is wide enough for some uses but too narrow for other uses. Moveover, some uses have been in place for a couple of centuries and are not easily usurped by newcomers. Imagine that you were traveling on a boat down the Rhine. Which of the following would you not expect to see within the graben? You would not expect to see ... [A] an autobahn (four-lane highway)....... /B] a main-trunk railroad....... /C] barges longer than 30 m (98 feet)....... /D] vineyards. …. /E] cabbage patches. [A] an autobahn (four-lane highway) 34. Fig. 9 illustrates orthogonal views of a plunging fold. The plunge on this fold is about .... [A] 5o ... /B] 12 o .... /C] 22 o .... /D] 32 o ...... /E] 72o /B] 12 o 35. In most introductory textbooks, rock deformation is discussed primarily at the scale of a hand sample or an outcrop. This scale is called ... [A] escalalarga.

.../B] escalapequena. .../C] macroscopic. .../D] macromedial. .../E] micromedial. C] macroscopic 36. Fig. 10 illustrates portions of two anticlines and two synclines. If you were to see the rocks which lie to the right and left of the illustrated scene, you would expect to find... [A] only synclines. . ..../B] only anticlines. . ..../C] both anticlines and synclines, as in this sketch. … /D] neither anticlines nor synclines. C] both anticlines and synclines, as in this sketch 37. Ductile deformation may occur during any natural deformation event. However, it must occur during only one of the following deformation events. The example which certainly is ductile is .. [A] impact of a falling boulder upon the base of a cliff. .../B] displacement of the Earth's surface along the San Andreas fault. .../C] folding of a bed of shale adjacent to the San Andreas fault, at a depth of several kilometers. …/D] dropping a ceramic duck onto a stack of tiles.

.../C] folding of a bed of shale adjacent to the San Andreas fault, at a depth of several kilometers 49. According to Plate Tectonic Theory, seafloor spreading annually ... [A] consumes more basaltic crust than one sees in all of Iceland. .... /B] creates about as much new surface area globally as subduction destroys. ..... /C] causes rocks that lie adjacent to spreading ridges to become so compressed (so much denser) that this compression accommodates all the expansion. B] creates about as much new surface area globally as subduction destroys 42.Fig. 12 is a paper record (a seismogram) of an earthquake. The zigzag line has been drawn by an oscillating pen which dangled downward onto the slowly rotating drum of a seismograph. Horizontal lengths in Fig. 12 correspond to known time intervals because.. [C] the drum on the instrument rotates at a fixed speed. 10.Fig. 1 includes some distortions. Which of the following is the greatest distortion? It is.. B] the maximum height of the tidal bulge compared to the radius of Earth. 8.If you were a drop of water at the bottom of either trough in Fig.

3, you would be moving.. A] horizontally to the left 12.For pure liquid H2O, the temperature of maximum density is. D] +4 Degrees C 50.There is tremendous friction within a subduction zone as the downgoing plate rubs against both the overlying and underlying surfaces, generating powerful earthquakes. Rocks which abut against the plate become sheared and mixed with rocks dragged from other layers within the deep Earth. The result is a heterogeneous rock which contains highly variable rock fragments. This heterogeneous rock is called a. D. Me'lange

Question: Agulhas, Kuroshio, Benguela, Canary and Humboldt are?
Answer: Ocean currents