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RECENT GEOLOGY OF COASTAL LOUISIANA
[摘要] Recent, in a technical geological sense, refers to the latest episode of geological time. Definitions vary. Northern European geologists are likely to refer to about the last 10,000 years for the reason that only the sedimentary deposits of such an interval are available for study. Geologists in the United States commonly regard the Recent as a post-glacial period of somewhat longer duration. Studies of materials containing the carbon isotope, C14, are resulting in time determinations in years. Louisiana geologists define Recent as that period of time during -which sea level made its last general rise. This may have lasted about 30,000 years. Sedimentary layers deposited during that period are regarded as Recent in age.
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[效力级别]  [学科分类] 建筑学
[关键词] Louisiana coastal geology;coastal landforms;land reclamation [时效性] 
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