There are three possibilities here:
1) He learned about shale oil from wikipedia
2) He's using an awkward metaphor for resource plays that he doesn't understand
3) He's calling oilsands oil shale

2&3 are boring, but I have an urge to talk about 1:
There are two very different things called shale oil.
The 'famous' type of shale oil (and shale gas) that's added millions of barrels a day in North America recently refers to oil or gas that's held in very 'tight' reservoirs.
Tight means that the porosity (open space) and permeability (ability of fluid to flow through it) are very small. Usually the tight reservoirs are made of shale or very shaly sandstone and so people have come to call it 'shale oil'. 3/n
The oil held in these tight reservoirs is usually regular light oil and it can be pumped to the surface and piped to a refinery just like any other, except that to get enough out to make money you need to drill horizontally to contact more reservoir and frac the well 4/n
(frac is short for hydraulic fracturing and I will never intentionally add a 'k' to it) in order break the rock up to artificially increase the permeability and let more oil flow. Those techniques (horizontal drilling and fraccing) have both been around for many decades. 5/n
But more recent advances allowed them to be combined to access the tight shaly reservoirs we always knew were full of oil but couldn't get at, set off a huge boom and now this is what everyone colloquially calls 'shale oil'.
But, when you google "shale oil" one of the first results will be the Wikipedia entry for the older but now much less common meaning. 7/n
When shales are deposited in shallow marine areas the sediment often contains lots of little bits of organic matter, mostly plankton and algae (these microscopic organisms and not dead dinosaurs are where most oil and gas actually come from btw). 8/n
When that organic matter decomposes it becomes something called kerogen, and as more and more sediment gets deposited over millions of years and the shale gets buried deeper and warms up the kerogen is 'cooked' into useful hydrocarbons like oil and gas. 9/n
Then over millions more years some of that oil and gas slowly leeches out of the shale 'source rock' into more permeable sandstone and limestone reservoirs. 10/n
Those sandstone and limestone reservoirs were relatively easy to get at, sometimes needing simple fracs or acid to help a little, and that's where all our 'conventional' oil wells went. 11/n
Then once we got better at drilling we were able to short circuit that slow leeching out from the source rock and get the oil directly from the source ourselves (again that was the first type of 'shale oil' or 'tight oil' we talked about) 12/n
But what if we wanted to skip the whole multi-million year natural 'cooking' process altogether? There is many times more immature kerogen than there is oil (including conventional, tight and oilsands) in the world. 13/n
Well it can be done! And that's the other meaning of shale oil, taking raw kerogen rich rocks and heating it under pressure to artificially turn the kerogen into oil. (Why wikipedia thinks this is what most people searching the term want to know about is beyond me). 14/n
Anyway it can be done through 'in-situ' (underground) processes, but the handful of significant developments do it by mining the rocks and bringing them to a facility. So you can have a 'shale oil mine'. 15/n
But 'can be done' isn't 'can make money' and as long as any other sources of oil exist those will be cheaper to produce. If our other sources run low though and we still need oil there are at least 6 TRILLION barrels (160 years of global supply) of this stuff out there. 16/n
The largest single reserve is in the Green River Shale of Colorado, which on its own probably contains more recoverable oil than all the traditional oil in the world combined 17/n
It's not new either, back in the early 20th century some projects even got to commercial production, but then cheaper conventional oil flooded the market and killed them. 18/n
Ironically it was the (other) shale oil boom that most recently killed slightly renewed interest in the OG shale oil industry in the early 21st century. 19/n
You can follow @tiffanyrg9.
Tip: mention @twtextapp on a Twitter thread with the keyword “unroll” to get a link to it.

Latest Threads Unrolled: