Sea Level History
نویسنده
چکیده
Bilal U. Haq and his co-workers have completed an important update of the chronology of coastal onlap and eustatic fluctuations in Mesozoic and Cenozoic time (1). Seismic stratigraphic results are augmented in the new charts by outcrop and well-log studies to document an impressive total of 119 sea level cycles since the beginning of the Triassic. In addition, the Cretaceous results have been published officially for the first time. However, apart from distinguishing between relative changes of coastal onlap and eustasy, the methodology and assumptions are much the same as those used to construct the first version ofthe "sea level curve" in 1977. In a recent evaluation of the seismic stratigraphic record of sea level change (2), we drew attention to two problems in particular. 1) All of the observed depositional cycles
منابع مشابه
Sea Level Variations over Geologic Time
Sea level changes have occurred throughout Earth history. The magnitudes and timing of sea level changes are extremely variable. They provide considerable insight into the tectonic and climatic history of the Earth, but remain difRcult to determine with accuracy. Sea level, where the world oceans intersect the continents, is hardly Rxed, as anyone who has stood on the shore for 6 hours or more ...
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