Word: sedimentality
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They are great underground mountains of salt, some of them six miles deep and three miles across. They were formed tens of millions of years ago-some even before the age of the dinosaurs-by the evaporation of ancient saline seas. Layer upon layer of sediment piled atop the dried-up ocean beds. Gradually, columns of the lighter salt were forced upward by the pressure, like putty squeezed through the fingers of a slowly clenching fist. In the U.S. alone, there are more than 500 such salt domes, all of them in or around the Gulf of Mexico...
...effects spread beyond the lakes. In some areas, humans may also be affected. In the Lac la Croix lake system of Ontario, where the Ojibway Indians fish for their livelihood, catches are showing high levels of mercury. Reason: the toxic metal, ordinarily concentrated in sediment, changes into an organic form, methyl mercury, in acid water and is then easily absorbed by the fish. While the threat to plants is not as well understood, acid rain can eat away at leaves, leach nutrients from the soil, interfere with photosynthesis, and affect the nitrogen-fixing capabilities of such plants as peas...
Evidence of this prehistoric jaunt was reported last week by U.S. geologists who had been excavating hillside sediments that were once part of the lake. The geological team, led by Kay Behrens-meyer and Leo LaPorte of the University of California at Santa Cruz, found seven footprints in a layer of sediment dated by radioactive clocks to be 1.5 million years old. All the prints apparently belonged to the same individual. One of them showed unmistakably that he, or perhaps she, had slipped while walking...
...Even in Lake Erie we now expect DDT to disappear completely in a rather short time. In fact, it is now difficult to find it anywhere in the lake except in the sediment...
...Paris of Saurashtra" because of its many green parks and broad avenues. Mud houses were entirely swept away, brick and concrete buildings were smashed, and just about everything else was buried under a layer of ooze almost 4 ft. thick. Rescue workers found bloated bodies half buried in the sediment and hanging from fences and tree branches. By week's end, some 1,100 corpses had been counted, and it seemed probable that the final toll would go even higher, not counting those killed in the 30-odd small villages between Morvi...