4D points the way to gas recovery
A study based on rock property work in BP Egypt's Ha'py field in the Nile Delta suggests that time-lapse seismic data in the cost-effective management of oilfield reservoirs could equally apply to gas fields.
Time-lapse or 4D seismic surveys could extend the life of gas reservoirs by identifying bypassed accumulations and identifying flow barriers. “Although the 3D effects will be smaller they should still be visible, especially in shallow gas reservoirs,” said the paper's author, Robert Francis Marten, a geophysicist with BP Egypt.
“As oil or gas is produced the reservoir experiences pressure and saturation changes. When these changes are large enough, repeat seismic surveys can track flood fronts and recognize barriers and bypassed pockets, which will have significant commercial benefits,” said Marten.
The modeling studies were carried in relation to Pliocene reservoirs in the Nile Delta where 14 trillion cubic feet of gas has been discovered and current production comes from numerous fields.
Marten's modelling study compiled with co-authors James Keggin and Giles Watts has been awarded the American Association of Petroleum Geologists (AAPG) 2002 Gabriel Dengo Memorial Award, to be presented in Salt Lake City US in May. — (menareport.com)
© 2003 Mena Report (www.menareport.com)