There are two basic types of glaciers, those that flow outward in all
directions with
little regard for any underlying terrain and those that are
confined by terrain to a
particular path.
Line The first category of glaciers
includes those massive blankets that cover whole
(5) continents, appropriately called ice sheets. There must be over
50,000 square kilometers
of land covered with ice for the glacier to qualify as an ice
sheet. When portions of an
ice sheet spread out over the ocean, they form ice shelves.
About 20,000 years ago the
Cordilleran Ice Sheet covered nearly all the mountains
in southern Alaska, western Canada, and the western United States.
It was about
(10) 3 kilometers deep at its thickest point in northern Alberta. Now
there are only two
sheets left on Earth, those covering Greenland and Antarctica.
Any domelike body of ice that
also flows out in all directions but covers less than
50,000 square kilometers is called an ice cap. Although ice caps
are rare nowadays,
there are a number in northeastern Canada, on Baffin Island, and
on the Queen
(15) Elizabeth Islands.
The second category of glaciers
includes those of a variety of shapes and sizes
generally called mountain or alpine glaciers. Mountain glaciers
are typically identified
by the landform that controls their flow. One form of mountain
glacier that resembles
an ice cap in that it flows outward in several directions is
called an ice field. The
(20) difference between an ice field and an ice cap is subtle.
Essentially, the flow of an ice
field is somewhat controlled by surrounding terrain and thus does
not have the domelike
shape of a cap. There are several ice fields in the Wrangell, St.
Elias, and Chugach
mountains of Alaska and northern British Columbia.
Less spectacular than large ice
fields are the most common types of mountain
(25) glaciers : the cirque and valley glaciers. Cirque glaciers are
found in depressions in the
surface of the land and have a characteristic circular shape. The
ice of valley glaciers,
bound by terrain, flows down valleys, curves around their corners,
and falls over cliffs.
Questions
9. What does the passage mainly discuss?
(A) Where major glaciers are
located
(B) How glaciers shape the land
(C) How glaciers are formed
(D) The different
kinds of glaciers
10. It can be inferred that ice sheets are so named for which of
the
following reasons?
(A) They are confined to
mountain valleys.
(B) They cover large areas of
land.
(C) They are thicker in some
areas than in others.
(D) They have a characteristic
circular shape.
11. According to the passage, where was the Cordilleran Ice Sheet
thickest ?
(A) Alaska
(B) Greenland
(C) Alberta
(D) Antarctica
12. The word “rare” in line 13 is closest in
meaning to
(A) small
(B) unusual
(C) valuable
(D) widespread
13. According to the passage (paragraph 5), ice fields resemble
ice caps in
which of the following ways?
(A) Their shape
(B) Their flow
(C) Their texture
(D) Their location
14. All of the following are alpine glaciers EXCEPT
(A) cirque glaciers
(B) ice caps
(C) valley glaciers
(D) ice fields
15. The word “depressions” in line 25 is closest in meaning to
(A) intrusion
(B) dejection
(C) concaves
(D) convexes
Please tally your answer with the below provided answers and
then comment here how much you got!
Answers
9. D 10. B 11.
C 12. B 13. B 14. B 15. C
Comments
Post a Comment