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Alchemy in the AbyssUSGS Public Lecture on Deep-Ocean Minerals
U.S. Geological Survey (USGS) marine geologist James Hein introduced listeners to the mysteries of deep-ocean minerals in a public lecture titled "Alchemy in the Abyss" on May 31 at the USGS center in Menlo Park, California. The demand for metals is increasing dramatically, especially in Asia, and nations are exploring to see whether mineral deposits in the deep ocean can help supply the new markets. Jim described the three main types of deep-ocean deposits:
The audience was fascinated by Jim's tales of deep-sea exploration using manned submersibles and remotely operated vehicles (ROVs). The lecture incorporated videos taken during some of Jim's cruises, including footage shot from an ROV of the first deep-sea volcanic eruption to be caught on film. The scientists thought they were filming a sulfur-rich hydrothermal plume until they saw dark rock fragments being ejected. The ROV was quickly retrieved and, once back on deck, was seen to be spattered with blobs of elemental sulfur from the eruption ejecta. (Read more about this expedition in "Exciting New Discoveries in Submarine Hydrothermal Systems," Sound Waves, July 2004.) Nautilus Minerals, Inc., based in Canada and Australia, plans to begin mining polymetallic sulfides (for gold and copper) from extinct hydrothermal mounds in the Exclusive Economic Zone (sea floor within 200 nautical miles) of Papua New Guinea in 2009, a fact that sparked questions about possible environmental impacts. Not much is known about deep-ocean ecosystems outside those at active vent sites, but other deep-ocean ecosystems are beginning to receive increasing attention through major international cooperative programs. The talk ended with a lively question-and-answer session, and many audience members lingered to speak to Jim afterwards. To see an archived video of the lecture, visit URL http://online.wr.usgs.gov/calendar/2007.html (scroll down).
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in this issue:
Public Lecture: Alchemy in the Abyss USGS at Florida's Marine Quest College Students Introduced to USGS Studies Potential Impacts of Future Sea-Level Rise Onshore-Offshore Geologic Map Workshop High-Resolution Map Merges Tampa Bay Bathymetry and Topography |