[Titanites]

How do you know it was sedimentary rock they drilled through?

There are several ways, including:

1. Cuttings: small pieces of the rock broken off by the drill bit during the drilling operation are returned to surface in the drilling mud being circulated.

2. Coring: a special bit and barrel are run into the ground to cut a piece of the rock for examination on surface.

3. Electrical Logging: special tools are run across the rock face and readings are taken of the rock properties and transmitted to surface for evaluation.

[blackpacific]

That all may be well known (not to me), but it was not clear from the article what type of material was encountered. I am sure with a little “digging” we can find out from the crew who drilled it what they went through. Unless they do not want competitors to know what is involved?

How many pounds mass of animal and plant matter is required to make a lb of oil? And how did it get so deep? I have seen the theories about plate tectonics being the cause of organic matter being drawn into the depths, but does it really compute?