In the early 1970s I developed a hydraulically powered portable submersible drill for collecting cores from coral-reef substrates ranging from the exposed reef flat to the deep fore reef. A marked improvement over earlier electric and pneumatic drilling techniques and destructive blasting, this new coring tool enabled scientists to at last obtain detailed information on the growth history of modem reef structures and their postdepositional processes. It consisted of an underwater hydraulic wrench fitted with standard drilling pipes and barrels, a hydraulic power source at the surface, and a Pump to circulate water around the cutting edge of the core bit. For optimum results, the operation required a three-man crew. In the past two decades, this drill and similar have been used sucessfully by numerous coral-reef researchers in the United States, Australia, Japan, and Germany. A classic example of the application of this equipment can be seen in a study of the growth history of a fringing reef off Galeta Point, Panama. Thirteen closely spaced core holes across this reef, extending from inshore mangroves to the outer fore-reef slope, produced valuable data on reef community succession, rate of framework construction, and postdepositional processes.
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原文发布时间:2009/5/6
引用本文:
Ian G. Macintyre.A DIVER-OPERATED SUBMERSIBLE DRILL FOR STUDYING THE GEOLOGICAL HISTORY OF CORAL REEFS.http://hftc.firstlight.cn/View.aspx?infoid=686901&cb=qinweinaxg.
发布时间:2009/5/6.检索时间:2024/12/14