The Marianas Trench
We often learn that top of Mount Everest is the tallest point above sea level (5.49 miles). But what about the lowest point below sea leave? The Mariana Trench-found in the waters of the Mariana (1) Archipelago, or Islands, in Micronesia-holds the record for deepest part of the oceans around the world. The trench, or ditch, can be compared to an underwater valley. Its depth has been recorded to reach over 6.8 miles (over 10.9 kilometers) below the sea surface. If you were (2) to stick Mount Everest in the trench, the top of this tallest mountain in the world wouldn’t touch the surface of the water. In fact, there would be a one-mile gap between the tip of the mountain and the surface’s waves.
Also known as Marianas Trench, The Mariana Trench gets its name from the Mariana Islands due to the (3) proximity of the trench to the Islands. The islands were named after Queen Mariana of Spain by the King’s explorer Fernando Magellan, who claimed the archipelago as a Spanish (4) colony. The trench was discovered in the late-19th century by a British team of scientists and oceanographers who sought to map the ocean floor by dragging lines, also known as sounding. Later, echo sounding was used to acquire a more accurate reading of the oceans’ depths.
The Mariana Trench is found at the (5) boundary of two tectonic plates, the Pacific Plate and the Mariana Plate. For millions of years, the Pacific Plate has been pushed below, or subducted beneath, the Mariana Plate, causing pressures leading to the formation of the Mariana Islands. Because of the formation of these plates, governments have proposed dumping nuclear waste deep into the trench, in hopes that because of the subduction of the Pacific Plate, the waste will be pushed down under this plate and therefore covered up. However, international law prohibits the dumping of nuclear waste in the ocean.
According to the author, which of the following is the reason that the Mariana Trench was discovered?
