Some of the direct consequences of this change in ecological balance relates 

 to man's use of the areas under attack by Acanthaster planet. Reefs and 

 atolls are havens for numerous fish species and are zones of high organic 

 productivity. Destruction of the coral material of the reefs would upset the 

 productivity of the reef, especially the productivity of fish useful to the 

 local inhabitants. 



Understanding of the long-term effects of the predatory action of the 

 "Crown of Thorns" is still rudimentary. For this reason, the Department 

 of the Interior is examining the results of several independent reports ^" 

 in order to formulate further research into the nature of the infestations 

 and future action in controlling or modifying the destruction of these 

 important natural resources. 



Global Deep Drilling Investigations 



An outstanding example of a major U.S. research program, which relates 

 to a global research problem, is the National Science Foundation's ocean 

 sediment coring program.^ Recovery of cores from areas where the water 

 depths are over 20,000 feet has demonstrated the great potential of the 

 drilling ship Glomar Challenger. By determining the ages of the oldest 

 sedimentary material in the cores the validity of the sea-floor spreading 

 concept can be tested — if the continents are drifting apart, the sea floor 

 sediments should be progressively younger in age near the proposed central 

 area from which tectonic motion emanates. Preliminary shipboard examina- 

 tion of the samples indicated that this systematic shift in the age of sediments 

 does occur, lending support to this hypothesis. A reconstruction of the 

 opening and formation of the Atlantic Ocean is now possible as a result 

 of the direct evidence recovered by deep sea drilling. 



Other signal discoveries from early examination of the corings have shown 

 that the rates of sedimentation in the deep ocean basins vary with time 

 and location by orders of magnitude. Corings taken in the Gulf of Mexico 

 from the Sigsbee Knolls and related buried structures of the deeper portions 

 of the Gulf revealed that these formations consisted of salt diapirs having 

 associated hydrocarbon deposits. 



Since much of our previous information concerning the igneous and 

 sedimentary material of the ocean bottom was inferred from indirect seis- 

 mic methods, the recovery of in situ rocks has answered questions of inter- 

 pretation of geophysical information. However, the drilling has also opened 

 up a multitude of problems relating to sequences of deeper sediments not 

 heretofore predicted from analyses of previous oceanographic and geo- 

 physical sediments. 



^" "Acanthaster planet — Impact on Pacific Coral Reefs," final report to U.S. Depart- 

 ment of the Interior, Research Laboratories, Westinghouse Electric Corp., Pittsburgh, 

 Pa., October 1969. ("Crown of Thorns" Workshop, University of CaHfornia, San 

 Diego, Scripps Institution of Oceanography, October 1969.) 



' Plans for the ocean sediment coring program were described in the Marine 

 Sciences Council's third annual report, "Marine Science Affairs — A Year of Broad- 

 ened Participation." 



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