Word: sediments
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...discover and map the 47,000-mile-long globe-girdling system of ridges and rifts-a landmark in geology. Heezen also studied the role of turbidity currents (underwater rivers of mud) in shaping the contours of the sea floor, and theorized that glassy particles called tektites in the ocean sediment were the result of the collision of meteorites or comets with the earth. Heezen co-authored a book titled The Face of the Deep...
...international consortium of scientists is compiling a record of the earth's climate. Climatologist Lamb and his colleagues have assembled an accurate historical record of the seasons going back as far as 1400 A.D.-based on parish registers, government documents, monastery records, and such physical evidence as sediment deposits in lakes and growth rings in trees. Says Lamb: "The more we know about cycles of the past, the better we can work with the highly detailed and sophisticated observations we have of our weather today." Geophysicist Willi Dansgaard of the University of Copenhagen is studying cores taken from...
...Geological Survey of Egypt and holds a seat in the Egyptian Parliament, bases his theory on evidence he found while doing test borings for the Aswan High Dam in 1961. In some of his core samples, Said was puzzled to find a layer of alluvial (deposited by running water) sediment at a depth of 450 ft., well below the level of the modern Mediterranean Sea. Convinced that such deposits could not have been left by today's Nile, Said began looking into the possibility that they were traces of an earlier river...
...Egypt's population, it should be noted that this project was not an unmitigated benefit. Although the dam made possible the cultivation of 1.3 million acres of formerly arid land, it stands accused of several disasters. The Egyptian Mediterranean fisheries have been virtually wiped out because the nutritional sediment washing downstream that formerly sustained sea life is now silting up the dam. In addition, salt water is moving upstream in the Delta, eroding farm land or making it saline. There has been an alarming spread of schistosomiasis. Also, a water weed is growing so fast in Lake Nasser behind...
Though this scenario for the beginning of the ice age has been well documented by fossil records, scientists have long been uncertain about what caused the cooling. Now, after studying cylindrical-core samples of ocean sediment dug up by the deep-sea drilling ship Glomar Challenger, two University of Rhode Island researchers have found evidence that may help provide the answer. The telltale position of layers of volcanic ash found in the cores by Geologists James Kennett and Robert Thunell suggests that the first great ice age could have been set off by a worldwide series of volcanic eruptions...