Post by
OILFINDER on Oct 12, 2006 1:46pm
Observations from field trip yesterday.
I added shares today.
No one has posted about the field trip yesterday, so I will do the honors.
The road, location, and drilling rig are all impressive. I was impressed with the drilling rig, drilling contractor, company man, mud loggers, etc. They are currently drilling at approximately 3500 feet.
From a geologist perspective, what impressed me most were the rocks they are currently drilling in, the penetration rate, and the fact they have had no loss circulation to date.
Translation:
The rocks they are currently drilling are massive intervals of arkose sand and/or pebble conglomerate. An arkose sand is composed of both quartz grains and feldspar grains which are cemented together with silica, calcite, but predominately clay. There has been no porosity intervals or loss circulation internals encountered to date. In other words they are drilling in what I would consider a good top seal.
The current estimate of the thickness of the rocks located in the hanging wall of a major thrust fault (over thrust) varies several thousand feet (personal communication). In other words, it is nearly impossible to determine the interval velocities and the depth to the thrust fault for proper seismic interpretation prior to drilling. All a geologist or geophysicists can do is generate multiple time/depth structure maps with various velocity models to see if the structure closure is real.
Assuming the rocks are hard and dense (cemented with silica), then the seismic data would be skewed by a velocity pull-up. To correct for a velocity pull-up a geologist or geophysicists would lower the depth to the thrust fault and/or formation tops, which would have a negative impact on the structure closure and the size of the structure.
Assuming the rocks are not hard and dense (cemented with clay) then the seismic data would be skewed by a velocity pull-down. To correct for a velocity pull-down a geologist or geophysicists would raise the depth to the thrust fault and/or formation tops, which would have a positive impact on the structure closure (size of the structure).
I'm betting (to date) the formation tops will come in high to prognosis. The shallow anticline axis, that was previously believed to exist north of the drill site, may be located further south. In other words, they may encounter commercial oil and gas below the first major thrust fault in a higher than anticipated structure trap.
At the current drilling penetration rate (fast for this interval), it is possible to encounter the first major thrust at a shallow depth and therefore encounter potential oil and gas zones at a shallow depth. Prior to the field trip I was under the impression that it would take perhaps 120 days before we had any good news. Now I’m under the impression that good news may be much sooner than expected.
OILFINDER