Re: Earthquakes and oil fields
Posted by chris in suburbia on June 29, 2006 at 05:56:21:

Hmmm...not easy to answer but I'll take a partial shot. You need sedimentary basins to have oil. You need these basins to be preserved....not thrust so deep that they are metamophosed. There is not much oil in the old cores of continents...the cratons. Plate boundaries, where there are lots of quakes, also have lots of vertical motions that can make sedimentary basins. But, these can be destroyed by subduction or other tectonic processes. The Middle East would not be considered part of the ring of fire...and not sure if there is any tectonic activity in Saudia Arabia/Kuwait/southern Iraq....but there is folding and thrusting in part of Iran. There is a lot of oil around part of the active Pacific margin...Los Angeles, Indonesia, points north..
You also need something to trap the oil, and to help it migrate into the traps...these would be folds and faults (although there are some big fields in non structural (stratigraphic) traps. One of the biggest oil provinces of of the US, maybe the biggest, is the Gulf of Mexico coast and offshore...and the Niger Delta and offshore is another big one...these are due to massive sedimentation, with the faults and folds being mainly mega-landslides (but seated at 6 km depth): these are normal growth faults driven by gravity.

Another question is whether oil and gas production can trigger earthquakes. The answer is "makes sense" in certain areas.
Chris


Follow Ups:
     ● Re: Earthquakes and oil fields - Canie  20:48:54 - 6/29/2006  (38907)  (0)
     ● Re: Earthquakes and oil fields - Barbara  07:00:51 - 6/29/2006  (38884)  (1)
        ● Re: Earthquakes and oil fields - chris in suburbia  14:46:56 - 6/29/2006  (38896)  (1)
           ● Thanks ... - Cathryn  16:37:09 - 6/30/2006  (38945)  (0)