by peakoilwhen » Tue 06 Mar 2018, 03:59:54
>' but most wells don't refill at economic rates!'
Yep. That's for 2 reasons
1. The current average depth of US wells is well above the depth where oil forms.
The upwell paths from the mantle to the upper crust are not certain to be continuous. Often they will have been cut off from the mantle, so that reserves become without a decent intake from the mantle.
2. Humans can typically drain any one upper-crust well faster than the mantle can restore it. But taking the full surface area of the Earth, the mantle far out produces what humans can consume.
So with (1), abiotic theory dictates that improved refill rates can be gained by simply drilling wells closer to mantle depth.
Also, if we are asserting that the mantle out-produces what humans can consume, then there should be a correspondence between depth and consumption rate. The more oil we need, the deeper we need to go.
This is what we find. Peakers like rockdoc don't care to mention that the great increase in US oil production over the last 70 years has come from drilling just an average of 1300ft deeper today than we did in 1949. ( 3700 ft -> 5000 ft )
If we need further increase the the US oil production by another 1949 to 2018 amount, just drop the wells another 1300 ft. Compare this with the record depth, which as far as I know is 35,050ft by deepwater horizon ( rockdoc and rockman have the actual record, but they are coy about revealing it, rd is too busy with telling the climate doomers they are wrong another 1000 times )
But the main point you need to understand is that most oil created in the mantle is destroyed in the mantle and lower crust. Its up to 1500C down there. If the oil gets near oxygen at lower pressures but high temperatures it will decompose. As rd will be glad to explain, oil is unstable in the lower crust, it needs to be lucky to stay in anoxic environments and also stay away from high temperature , low pressure environments, else it may decompose back to water, CO2 or methane ( needs catalysts , temperature and pressure won't do it alone ).
Only a small fraction of oil created in the Earth makes it to the upper crust. Most of Earth's petroleum stays in the mantle and lower crust and is short lived on the geologic scale, but on the human scale its stable.
Dig deeper and we'll tap into these mantle oil supplies that dwarf the relic reserves and tenuous refill rates we find in the upper crust.
Hence when BP tried tapping lower crust oil in 2010, the tremendous pressure and quantity of it was beyound anything that biotic oil believers imagined or had asked for in the design of the state of the art deepwater horizon rig, which was destroyed by the oil.
But like I say, average oil wells won't get anywhere near the lower crust in our lifetimes. They won't need to. Just dropping the average depth another 1300ft greatly increases the production rates sufficient for another 70 years.