Word: layers
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...Tranquility Base, 150 miles to the northeast). Far more significant is the geological diversity of the landing area. It may contain three basically different types of material: 1) original crustal rock dating back to the moon's birth some 4.6 billion years ago; 2) a layer that was melted and then hardened after the great asteroid impacts that created such large features as the Sea of Rains nearly a billion years later; and 3) more recent lava flows, possibly produced by the eruption of volcanoes. Explains Caltech Geologist Eugene Shoemaker: "The geology of the lunar highlands is incredibly difficult...
...roughly the size of three football fields. At least 47 were killed and 56 injured, either in the blasts or in the fires that leveled every shack and lean-to in the area. By late morning, cabled TIME Correspondent Stanley Cloud, "nothing was left but a smoldering, stinking layer of ashes littered with the charred corpses of chickens, pigs and people. I learned that it is sometimes difficult to distinguish the petrified, ashen remains of a pig from those of a human being, particularly if the human being was a child whose lower limbs were blown off in the explosions...
...answer may lie in a theory suggested by Astronomer Bradford A. Smith of New Mexico State University and others long before Mariner 9 took off. Smith says that water may be stored as ice in the planet's northern polar cap under a thin layer of frozen carbon dioxide, or dry ice. That hidden water, he says, may be released periodically into the Martian atmosphere, producing regional rains and perhaps floods to erode the arid Martian surface. Bemused scientists at Caltech's Jet Propulsion Lab are now calling Smith's rains Martian "monsoons...
...GOOD DIGGER, one supervisor explained, does not require constant attention. He learns quickly, can be trusted to recognize what he is looking for, and will not accidentally slice through a deeper layer while scraping the top off an earlier layer. Discipline on the sites was strict, and it was no easy trick to slough off. It could be done, and diggers were caught napping in deep graves or sunbathing in trenches. Those who were languid, or in some manner troublesome, were asked to leave town. Some volunteers never caught on, and the worst ones were legendary. One year a particularly...
...Winchester sites involved three processes fundamental to any excavation. The first consists of making a complete record of an individual site. At critical or conclusive stages, the site was photographed for documentation of the evidence. Actual digging produced finds for phasing. A phase is a group of layers which belong together chronologically. The relationship of these finds to a layer helps date the layer and suggests the chronological development of that structure or area being investigated...