Mornings for me involve dealing with the domestic world (Joe, the dog and starting the day) and checking up on the world. Sometimes totally unrelated things from each world collide in my mind and I had one of those crashes this morning. After checking the fracking issue I've been following (and will start a blog on I promise) and an ad I saw for heavy oil extraction experts I read this Oil Drum piece on the global oil supply. Shortly after I saw that the toothpaste was getting low right and voila, I realized the toothpaste tube was great metaphor for the oil and gas situation.
Let me backtrack a moment. Petroleum and natural gas form from the remains of marine algae deposited along with marine muds to form what will become black shale source rocks. These shales have to be cooked at the right temperature and pressure in the crust to form petroleum. Too much you get only natural gas, too little and you get a waxy precursor called kerogen (the oil is so-called oil shales). Now shales are made from tiny silt particles and thus have very small pore spaces that are poorly connected to each other. Any gas or liquid or gas in the shales must travel very slowly and in small quantities. The petroleum and gas we traditionally extracted came not from the source rocks, but more permeable reservoir rocks that the fluids slowly migrated into over millions of years. The oil and gas must also be trapped somehow in this reservoir otherwise they'll continue to the surface where the gas escapes to the surface and the oil turns to bitumen or tar.
Now the goal has always been to find the oil still trapped in the reservoirs because such crude oil is the easiest to refine. More specifically the best crude is light (flows easily and has lighter fractions we can readily use) and is "sweet"or low in sulfur. And of course it is cheaper to extract on dry land than offshore, particularly the deep continental shelf.
Now think about the sources that are currently being promoted: oil sands, heavy oils, deep offshore drilling and fracking. These sources were traditionally the "trash fish" of the fossil fuel industry. The first two are not readily refined because they have lost the light fractions we need for diesel fuel, aviation fuel and gasoline and a heavily contaminated. Thus they need a lot of processing to just get to the crude oil stage, using a lot of energy, water and money to do so. Deepwater drilling is expensive and risky, remember Deepwater Horizon? Most people seem to have forgotten. Anyway the fact they're willing to go there shows the easy sources have been found and tapped. Same with fracking, it's an expensive and complicated process to turn the tight source rock into a reservoir and its only viable because we've found all the easily extracted stuff.
This brings us back to the toothpaste tube. When we started extracting petroleum and natural gas we had a brand new full tube and it literally burst out of the ground. For years thereafter we could just squeeze the tube a little and still get all we wanted. One day we started to have a little difficulty, the tube was squashed, misshapen and lumpy. So we go to enhanced extraction and rolled up the tube from the bottom and our production stayed high. But that only lasted a short while longer, so now we're in the process of squeezing the tube with vise grips and adding water to the dried paste in the cap and on the sink. Soon we'll be cutting the tube open and flushing out the inside.
Of course I never go to such lengths with tootpaste, I just run to the store. But old mother Earth has only one toothpaste tube, maybe we can squeeze all we need for another decade or so but inevitably our increasing efforts will only produce diminishing returns.
Well, I guess we can always get toothpaste from coal!