بنك الاسئلة ESR 2010 1ST 412

ANSWER THE FOLLOWING QUESTIONS:-

Part I "essay" "20 points"

1)    What is the Wilson Cycle, and why it is significant with regard to plate tectonics and ocean basins?

2)     There are two types of lithosphere, oceanic and continental, so there are three possibilities at a convergent boundary: (explain, mention the 3 types with example for each). In which of these cases can subduction occur.

3)     What is an ophiolite?

4)     Arabian shield is divided into 5 microplates (terranes) separated by 4 suture zone, explain with simple map showing the location.

Part II (short answer) "13 points"

5) Continental lithosphere never subducts (True or False)…True

6) Because of its relatively low density, continental crust cannot subduct. (True) or (False). True

7). The asthenosphere is partially melted and capable of slow, plastic flow. (True) or (False). True

8)- Deep ocean trenches occur over divergent (rift zone) boundaries. (True) or (False).False

9) Collision zones always involve two continental plates. (True) or (False). True

10) Which plate boundaries have the largest magnitude earthquakes? One answer

(     ) divergent and convergent

(  Yes   ) Transform and convergent

12)  What is the San Andreas Fault in southern California an example of?
(      ) Active continental margin
(      ) Convergent plate boundary
(      )  Divergent plate boundary
(      ) Passive continental margin
(   yes   ) Transform plate boundary

13) As a result of seafloor spreading:

(   )  new ocean crust is generated at ridges to accommodate the spreading plates

(  ) continents attached to the plates on each side of the ridge slowly move apart

(     ) The age of ocean crust increases with increasing distance away from the ridge

(   ) A record of paleomagnetic reversals is recorded in rocks that formed at the ridge

(    yes  )   All of the above

14). The three types of tectonic plate boundaries are:

(    ) Normal, reverse, and strike-slip

(    ) Active, passive, and extinct

(   yes ) Divergent, convergent, and transform

(    ) Seismic, volcanic, and subducting

(    ) Ocean-ocean, ocean-continent, and continent-continent

15) What does plate tectonic theory predict about the distribution of volcanoes and earthquakes?
(    ) They should be evenly distributed throughout the earth.
(   yes ) They should occur primarily along plate boundaries.
(    ) They should occur primarily in deep ocean basins.
(    ) They should occur primarily on continents.
(    ) They should only occur along continental margins.

16) What major lithospheric plate is composed primarily of oceanic lithosphere? Pacific plate

17) Match the geologic features with the type of plate boundaries they are  associated with. "5 points"

18) Match each mountain/island system with the kind of convergent plate boundary that formed it (if any). "4 points"

19)  What is a transform fault?     

(   yes) A strike-slip fault that forms the boundary between tectonic plates

(     )  A dip-slip fault connecting an anticline with a syncline

(     )   A reverse fault that steepens into a thrust fault

(     )  The rift-bounding faults on a mid-ocean ridge

Part III "Complete" "8 points"

(1)   Iron, copper, zinc sulfides, +/- manganese, gold, and silver formed in (rift zones; convergent boundaries, island arcs, transform faults)

(2)  Tungsten, copper, lead-zinc-silver ore bodies formed in (rift zones; convergent boundaries, island arcs, transform faults)

(3)   Chromite in ophiolites & massive sulfide ore deposits formed in (rift zones; convergent boundaries, island arcs, transform faults)

(4)  The two dominant features associated with subduction zones are……………………….and ……………………………..: