Petroleum geology
Raining hydrocarbons in the Gulf
Below the Gulf of Mexico, hydrocarbons flow upward through an intricate network of conduits and reservoirs. They start in thin layers of source rock and, from there, buoyantly rise to the surface. On their way up, the hydrocarbons collect in little rivulets, and create temporary pockets like rain filling a pond. Eventually most escape to the ocean. And, this is all happening now, not millions and millions of years ago, says Larry Cathles, a chemical geologist at Cornell University.
"We're dealing with this giant flow-through system where the hydrocarbons are generating now, moving through the overlying strata now, building the reservoirs now and spilling out into the ocean now," Cathles says.
He's bringing this new view of an active hydrocarbon cycle to industry, hoping it will lead to larger oil and gas discoveries. By matching the chemical signatures of the oil and gas with geologic models for the structures below the seafloor, petroleum geologists could tap into reserves larger than the North Sea, says Cathles, who presented his findings at the meeting of the American Chemical Society in New Orleans on March 27.
This canvas image of the study area shows the top of salt surface (salt domes are spikes) in the Gas Research Institute study area and four areas of detailed study (stratigraphic layers). The oil fields seen here are Tiger Shoals, South Marsh Island 9 (SMI 9), the South Eugene Island Block 330 area (SEI 330), and Green Canyon 184 area (Jolliet reservoirs). In this area, 125 kilometers by 200 kilometers, Larry Cathles of Cornell University and his team estimate hydrocarbon reserves larger than those of the North Sea. Image by Larry Cathles.
Cathles and his team estimate that in a study area of about 9,600 square miles off the coast of Louisiana, source rocks a dozen kilometers down have generated as much as 184 billion tons of oil and gas — about 1,000 billion barrels of oil and gas equivalent. "That's 30 percent more than we humans have consumed over the entire petroleum era," Cathles says. "And that's just this one little postage stamp area; if this is going on worldwide, then there's a lot of hydrocarbons venting out."http://www.geotimes.org/june03/NN_gulf.html
Raining hydrocarbons in the Gulf
Below the Gulf of Mexico, hydrocarbons flow upward through an intricate network of conduits and reservoirs. They start in thin layers of source rock and, from there, buoyantly rise to the surface. On their way up, the hydrocarbons collect in little rivulets, and create temporary pockets like rain filling a pond. Eventually most escape to the ocean. And, this is all happening now, not millions and millions of years ago, says Larry Cathles, a chemical geologist at Cornell University.
He's bringing this new view of an active hydrocarbon cycle to industry, hoping it will lead to larger oil and gas discoveries. By matching the chemical signatures of the oil and gas with geologic models for the structures below the seafloor, petroleum geologists could tap into reserves larger than the North Sea, says Cathles, who presented his findings at the meeting of the American Chemical Society in New Orleans on March 27.
This canvas image of the study area shows the top of salt surface (salt domes are spikes) in the Gas Research Institute study area and four areas of detailed study (stratigraphic layers). The oil fields seen here are Tiger Shoals, South Marsh Island 9 (SMI 9), the South Eugene Island Block 330 area (SEI 330), and Green Canyon 184 area (Jolliet reservoirs). In this area, 125 kilometers by 200 kilometers, Larry Cathles of Cornell University and his team estimate hydrocarbon reserves larger than those of the North Sea. Image by Larry Cathles.
Cathles and his team estimate that in a study area of about 9,600 square miles off the coast of Louisiana, source rocks a dozen kilometers down have generated as much as 184 billion tons of oil and gas — about 1,000 billion barrels of oil and gas equivalent. "That's 30 percent more than we humans have consumed over the entire petroleum era," Cathles says. "And that's just this one little postage stamp area; if this is going on worldwide, then there's a lot of hydrocarbons venting out."http://www.geotimes.org/june03/NN_gulf.html