Samples of earth extracted from deep beneath the sea, off the coast of Spain and Portugal, show climate shifts as early as 6 million years ago.
But a 小蝌蚪APP researcher said other clues revealed in those samples may be even more significant, especially for the oil and gas industry.
Dr. Carl Richter, a geologist in the 小蝌蚪APP小蝌蚪APP檚 School of Geosciences, is one of 35 scientists from 14 countries who participated in Integrated Ocean Drilling Program Expedition 339. From November 2011 to January 2012, they worked on board "JOIDES Resolution," a research vessel.
The team小蝌蚪APP檚 findings are published in the June 13 issue of "Science" magazine.
During the expedition, the scientists took core samples from a three-mile stretch near the Strait of Gibraltar, which is a gateway between the Atlantic Ocean and the Mediterranean Sea. They then examined the sedimentary record produced there by strong ocean currents, commonly called Mediterranean outflow water.
小蝌蚪APP淥ur initial goal was to understand how the Strait of Gibraltar acted first as a barrier and then as a gateway over the past 6 million years as the currents passed through the area,小蝌蚪APP Richter said. 小蝌蚪APP淏ecause the Mediterranean outflow water is saltier and heavier than the Atlantic waters, it plunges more than 3,000 feet downslope, carving deep-sea channels, and building up mountains of mud in these unique underwater landscapes. We now have first results for understanding the history of these currents through the Gibraltar gateway.小蝌蚪APP
The scientists also found new evidence of 小蝌蚪APP渁 deep-earth tectonic pulse小蝌蚪APP in the region. Shifts in the Earth小蝌蚪APP檚 crust are believed to be a major cause of environmental change.
Richter said the sediments collected during the expedition indicate that 小蝌蚪APP渙ceans and climate are closely linked.小蝌蚪APP
Further analysis showed that the sediments contained far more sand than expected. A sheet of sand extends about 60 miles from the Gibraltar gateway; it is evidence of the strength and velocity of Mediterranean currents.
The research team小蝌蚪APP檚 findings could impact future oil and gas exploration, according to the geologist.
小蝌蚪APP淭he thickness, extent, and properties of these sands make them an ideal target in places where they are buried deeply enough to allow for the trapping of oil and gas,小蝌蚪APP he said.
The research team小蝌蚪APP檚 abstract notes: 小蝌蚪APP淭hese sands represent a completely new and important exploration target for potential oil and gas reservoirs.小蝌蚪APP
Expedition 339 was funded by the U.S. National Science Foundation and implemented by the Integrated Ocean Drilling Program 小蝌蚪APP U.S. Implementing Organization. The research was partially supported by European grants and the Continental Margins Research Group at Royal Holloway 小蝌蚪APP of London.
For more information about this IODP Expedition, visit
Photo credit: John Beck, IODP/TAMU
Expedition 339 started in Ponta Delgada, Azores, in November 2011. An international team of scientists was on board the JOIDES Resolution, the research vessel shown.