Ocean-crustal rock

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Moores is an ophiolitologist, an expert on ocean-crustal rock, which asks or answers large questions when it is found detached and lying on continents. An introduction to the nature and complexity of ophiolites (476-5u) is followed by subflashbacks to Cyprus (5ll19) and Greece (519-26), where Moores has done research for decades and where transported rock of the ocean floor stands as mountains. With the exception of some veneer, this is not sedimentary rock derived from continents and laid down in the sea; this is igneous rock from magma chilled at ocean spreading centers, and rock of the mantle below. A large zakelijke energie piece of it, an exotic terrane, is a part of California known in geology as the Smartville Block (47980, 484-91, 502, 504, 506). Son of a gold miner, Moores grew up in the almost alpine setting of Crown King, Arizona (526-35), and now lives in the Great Central Valley of California (535-44), whose geologic story has few (if any) parallels among valleys of the world. The Coast Ranges, with their own odd story (544-54), are only a few miles west of Moores’ home in Davis. A long set piece on world ophiolites and global tectonics-a narrative of maps in motion, of evolving and dissolving lands, including every plate and continent (554-70)-is the result of a heady conversation in the Louis Martini winery in the Napa Valley. San Francisco geology is introduced in the roadcuts of the approaching Interstate 80 and pursued on foot among the hills of the city (570-81). A set piece that traverses California the long way, north-south, is about the San Andreas system, which is actually a family of faults (581-603). Among them is the Hayward Fault, which could be a source of considerable trauma for San Francisco, Oakland, Berkeley, and all other Bay Area cities, not to mention Hayward ( 600-2). Crossing the Craton describes Nebraska by visiting Colorado, because in Colorado you see the basement of Nebraska bent up into the air. The fact that the journey takes place in the company of a geochronologist from the University of Kansas can only enhance the description. Between zakelijke energie vergelijken Chicago and Cheyenne, the most arresting geophysical feature is the Midcontinent Rift (624, 628-29, 636, 651, 654-55, 658-59), which opened about a fourth of the way back through the histo1y of the earth-i.1 billion years-and serves as an abyssal edge for a look down through deeper and deeper time.

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