02 December, 2013

Predicting Gas Hydrates using Pre-stack Seismic data in Deepwater GOM

 

Gas hydrates, ice-like substances composed of water and gas molecules (methane, ethane, propane, etc.), occur in permafrost areas and in deep water marine environments.

Gas hydrates, ice-like substances composed of water and gas molecules (methane, ethane, propane, etc.), occur in permafrost areas and in deep water marine environments. In the Gulf of Mexico, where water depths are greater than 500 m, hydrates are found in the sediments near the sea floor. Hydrates can be viewed as an unconventional resource, as this concentrated form of natural gas is similar to compressed gas. A unit volume of crystalline methane hydrate contains as much methane as 164 times the unit volume of natural gas at sea level pressure. Worldwide accumulations of gas hydrates have been estimated to be 700,000 TCF of natural gas, of which 200,000 TCF are within the United States.

A promising methodology for predicting saturations of gas hydrates (Sgh), using industry standard 3D seismic data, involves an integrated workflow of seismic interpretation, rock physics analysis and model building, and seismic data inversion. An example study will be shown, which employed the Sgh results for the selection of well locations that would be drilled in 2009 by the Chevron-led Joint Industry Project (JIP) in deepwater Gulf of Mexico. Initial findings indicate that the methodology works well for predicting gas hydrate saturations occurring in thick sand units. Test wells drilled where high Sgh values were predicted consistently encountered high gas hydrate concentrations in massive sands.

The live portion will be followed by a full day of independent study (not a live event). The one-hour live e-symposium can be accessed from any computer anywhere in the world using a high-speed internet connection. After the event is over, you will receive via email information about accessing the asynchronous segment (not live) which consists of your independent study materials, to be accessed and studied at any time. You will be able to email responses to the readings, along with your study question answers for CEU credit (if you sign up for the extended package).