Operational re-entry accomplished by DSDP


  • Anonymous


The Deep Sea Drilling Project, sponsored by the National Science Foundation, completed successful operational use of the re-entry technique to recover ancient deep-sea sediment beneath the Caribbean Sea.

Operating in water 13,000 feet deep in the Venezuelan Basin of the Caribbean, aboard the drilling research vessel Glomar Challenger, the expedition replaced a worn drill bit after drilling 2300 feet. They then re-entered the same five-inch bore hole at the bottom of the sea with a more-than three-mile drill string and drilled 200 additional feet to recover chert, hard limestone and crystalline rocks previously unattainable even to the DSDP drilling because of layers of chert, or flint-like rock.