Word: sediment
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...most recent steps to make the vaccine safer. There were "striking differences," said Scheele, in "the degree of clarity of the different fluids" from which the various manufacturers have prepared vaccine. After the virus is grown in a broth of monkey-kidney tissue and left standing, a sediment may appear at the bottom of the flasks. The sediment is like lumps in porridge. When formaldehyde is added to kill the virus, it cannot reach the particles in the middle of the lumps, thus leaving them dangerously infective...
Heezen believes that they are the flood plains and deltas of "turbidity currents": rivers of mud, heavier than clear water, that coursed intermittently down the slopes of the continents and deposited their sediment far out on the bottom of the ocean. Most of the sediment, he thinks, was carried down in remote geological ages. The turbidity currents probably started near land. They cut deep gorges (e.g., the famous Hudson Canyon) in the continental slopes and dumped their silt and sand in deep basins in the irregular ocean bottom. When the nearest basin was full, the mud-river ran across...
Later the climate grew wetter, and the rivers cleared the shallow sea of its heavy brine. Some of the salt on the bottom probably dissolved, but the rest was protected by sediment washed down from the land. As the sediment grew thicker, it pressed on the underlying salt, and the salt (comparatively light and plastic) billowed up through it like slow-motion bubbles rising in a viscous liquid...
These rockbound bubbles of salt, one or two miles across and sometimes taller than the Rocky Mountains, are the famed salt domes of the Gulf Coast. In the eyes of the oilmen, they are lovely things. As the salt pokes through the sediment beds, it bends and breaks them and drags them upward, forming many pockets to trap the oil that has formed from marine organisms buried in the sediments. Best of all, salt domes all but shout, "Here we are!" To an oil geologist using the proper instruments (gravimeters and seismographs), a deeply buried dome stands out like...
...herd of them, searching desperately for water, must have lumbered out on the caked floor of a dried-up lake. The crust broke and lowered them into soft, smothering clay. Then sediment covered their skeletons and preserved them perfectly. There. Dr. Stirton came upon remains of the great, out-of-date beasts, some of them with their legs doubled under them as they waited for death. He hopes that more digging will turn up, among other things, the delicate skeletons of baby diprotodons that were smothered in their mothers' pouches when they sank into...