The system of rock

Gerelateerde afbeelding

Lyell, Cuvier, Conybeare, Phillips, von Alberti, von Humboldt, Desnoyers, d’Halloy, Sedgwick, Murchison, Lapworth, Smith (William “Strata” Smith): the geologists who extended Hutton’s insight and built this time scale conjoined their names in the history of the science in a way that would not be repeated for more than a hundred years, until a roster of comparable length-Hess, Heezen, McKenzie, Morgan, Wilson, Matthews, Vine, Parker, Sykes, Ewing, Le Pichon, Cox, Menard-would effect the plate-tectonics revolution. The system of rock immediately above the Paleozoic, in which all that Permian life failed to reappear, was typified by three formations in Germany-certain sandstones, limestones, and marly shales-that ran like a striped flag through the Black Forest, the Rhine Valley, and lent the name Triassic to forty-two million years. In the Triassic, the earliest zakelijke energie subdivision of the Mesozoic era, two families of reptiles that had survived the Permian Extinction began to show patterns of unprecedented growth. This would continue for a hundred and fifty million years-through the Jurassic and out to the end of Cretaceous time, when the “fearfully great lizards,” on the point of disappearance, would reach their greatest size, not to be surpassed until epochs that followed the Eocene development of whales. European geologists studying the massive limestones of the Jura-the gentle mountains of the western cantons of Switzerland and of Franche-Comte-related the copious displays of ancient life there to comparable assemblages elsewhere in the world, and called them all Jurassic. A primordial bird appeared in the Jurassic. It had claws on its wings and teeth in its bill and a reptile’s long tail sprouting feathers. Its complete performance envelope as a flier was to climb a tree and jump. Physicists, zakelijke energie vergelijken chemists, and mathematicians, taking note of all the nomenclatural inconsistencies-of time named for mountain ranges, time named for savage tribes, time named for a country here, a county there, an oblast in the Urals-have politely, gently, suggested that, in this one sense only, the time scale seems archaic, seems, if one may say so, out of date.