For a wrong word, underline
the wrong word and write the correct one in the blank provided at
the end of the line. For a missing word,
mark the position of the missing word with a "∧" sign and
write the word
you believe to be missing in the blank
provided at the end of the line. For an unnecessary word,
cross the unnecessary word with a stash "—" and put the word in the
blank
provided at the end of the line.
The ocean bottom—a region nearly 2.5 times greater than the
total land area of the earth—is a vast frontier that even today is largely
unexplored and uncharted. Until about a century ago, the deep-ocean floor was
completely accessible, hidden
(1) ______ beneath waters averaging over 3,600 meters deep. Totally
without light and subjected intense pressures hundreds of times greater
(2) ______ than at the Earth’s
surface, the deep-ocean bottom is a hostile environment to humans, in some
ways as forbidding and remote as the void of out space.
(3)
______ Therefore researchers have been taking samples of
(4)
______ deep-ocean rocks and sediments for over a century, the
first detailed global investigation of the ocean bottom did actually
(5) ______ start until 1968, with
the beginning of the National Science Foundation’s Deep Sea Drilling Project
(DSDP). Used techniques first developed for the offshore, oil
and (6) ______ gas
industry, the DSDP’s drill ship, the Glomar Challenger, was able to maintain
a steady position on the ocean’s surface and drill very deep waters,
extracting samples of sediments
(7) ______ and rock from the ocean floor. The Glomar
Challenger’s core samples have allowed geologists to reconstruct that the
planet looked like hundreds (8)
______ of millions of years ago and to calculate what it will
probably look like millions of years in the future. Today largely on
the strength of evidence gathered during the Glomar Challenger’s voyages,
nearly all earth scientists agree with
(9) ______ the theories of plate construction and continental
drift that explain many of the geological processes that shape on the
(10)
______ Earth.