Guest post by David Archibald Logistic decline plots may be misleading when the productionprofile has been affected by political events. Nevertheless, Figure1 shows a logistic decline plot for Russia s conventionalproduction. The result is in line with Russian estimates of theirultimate recoverable reserves of conventional oil and theproportion produced to date. The logistic decline plot assumes nochange in technology. It accounts for future conventionaldiscoveries but does not account for a new play type that has notbeen hunted before such as shale oil. Figure 1: Russia Logistic Decline Plot Production usually starts declining once a country has producedmore than 50% of its ultimate recoverable reserves. Russia sproduction decline was delayed by the turmoil of the 1990s.Assuming that Russia s conventional oil production is on the cuspof decline and that decline rate is 6% per annum, Figure 2 showswhat that decline will look like to 2040. At 6% per annum decline,Russia s conventional reserves will be exhausted by the end of thecentury. Figure 2: Russia Production Profile of Conventional Oil 1930 2040 Russia s shale oil resources are potentially enormous. The bestsource of information on this is a U.S. Geological Survey Report: G.F.Ulmishek, 2003, Petroleum Geology and Resources of the WestSiberian Basin, Russia, U.S. Geological Survey Bulletin 2201-G, 49pp. As at 2003 and as estimated by the USGS, the West Siberian Basinhad discovered reserves of 144 billion barrels of oil and more than1,300 TCF of gas. The assessed mean undiscovered resources are 55.2billion barrels of oil, 642.9 trillion cubic feet of gas, and 20.5billion barrels of natural gas liquids. Most of the undiscoveredconventional reserves are assumed to be in stratigraphic traps. 90%of the reserves are thought to be sourced from the BazhenovFormation. The Bazhenov Formation is an Upper Jurassic unit deposited in adeep marine environment. It is 25 to 50 metres thick over thecentre of the basin, where it is also in the upper part of the oilwindow of source rock maturation. Figure 7 is from page 12 of the Ulimshek report. It is an isopachmap of the Bazhenov Formation. The green blobs are oilfields withinthe Bazhenov. Figure 8 is from page 8 of the Ulmishek report. From the centre ofthe basin in a transect through Surgat, it shows the BazhenovFormation and the prograding deltas that built over it in about 400metres of water. The relevance of this cross-section is that itillustrates the deep marine environment that the Bazhenov Formationwas deposited in. The Bazhenov Formation is 2,500 metres deep inthe area of this cross-section, so there is another 2,000 metres ofsediment on top of what is shown in this figure. Figure 16 is from page 23 of the Ulmishek report. It shows thetotal organic carbon content (TOC) of the Bazhenov Formation. Mostof the central part of the basin has TOCs over 7% with some largeareas over 11%. By comparison, the oil generative part of theBakken has a TOC of 18% in outcrop where it is immature and 11%within the oil window, with the difference due to expulsion of oilin the latter. There are 45 feet (14 metres) of generative shalesin the Bakken. So the Bakken and the Bazhenov Formations are verysimilar in generative potential per cubic metre of rock, with theBazhenov being twice as thick. Figure 17 is page 24 of the Ulmishek report. It is a map of thevitrinite reflectance of the Bazhenov Formation. The green ismarginally mature and the oil window is shown by grey and brown.Combining the data from Figures 7, 16 and 17, there is a sweet spotfor the shale oil potential of the Bazhenov Formation the centre ofthe West Siberian Basin that covers about 800,000 squarekilometres. The Bazhenov Formation is particularly favourable for shale oildevelopment. Consider these passages from the Ulmishek report. The Bazhenov Formation commonly is 20 40 m thick; locally thethickness increases to 50 60 m. The formation covers an area ofalmost one million square kilometers and contains about 18 trilliontons of organic matter (Kontorovich and others, 1997). page 22 The organic matter in the Bazhenov Formation is derived fromplankton and bacteria. The TOC content averages 5.1 percent overthe entire formation (Kontorovich and others, 1997). In a largecentral part of the basin, TOC is higher than 9 percent, and inmany analyzed samples it is higher than 15 percent. page 22 Unconventional reservoirs in fractured Bazhenov shales are poorlyunderstood. The shales are commercially productive in the Salym andadjacent fields (Greater Salym area), where nearly 200 wells weredrilled into the Bazhenov Formation and the reservoir rocks arebest studied (fig. 15). No significant commercial production hasbeen established in other areas of the Bazhenov-Neocomian TPS,although oil flows were tested in many wells. The conventionalanalytical measurements of porosity and permeability in cores donot reflect properties of the shale rocks at reservoir depthsbecause of fracturing induced during drilling and lifting of thecores (Dorofeeva and others, 1992). Well logs also are unable toidentify reservoir intervals in the formation (Klubova, 1988).Indirect estimates of porosity of productive reservoir rocks in theGreater Salym area vary between 5 and 10 percent. Porosity isrelated to leaching of silica from radiolarians (Dorofeeva andothers, 1992), transformation of montmorillonite to illite(Klubova, 1988), or to both processes. Permeability of the shalesresults totally from fracturing, although the volume of fracturesis small compared with the pore volume. Horizontal fracturingstrongly dominates over fracturing in other directions. In someinstances, the fracturing is so intense that the rocks cannot becored. The fracturing was originated by hydrocarbon generation andrelated increase of pore pressure (Nesterov and others, 1987). Oil produced in the Greater Salym area from fractured self-sourcedreservoirs of the Bazhenov Formation contains little or no water,as bottom water in conventionally producible pools is absent.Productive wells commonly alternate with dry wells. Only about 20percent of drilled wells are commercially productive, another 20percent are dry, and the rest of the wells produced noncommercialor marginally commercial oil flows (Dorofeeva and others, 1992).During the last 25 years, only about 20 million barrels of oil wereproduced from the Bazhenov reservoirs of the area (Shakhnovsky,1996). Oil pools are strongly overpressured; the reservoir pressurein the Salym field is 1.7 times higher than the hydrostaticpressure. At a depth of 2,700 m, the reservoir pressure is as highas 50 MPa (7,250 psi) (Matusevich and others, 1997). Laterally, themagnitude of overpressure commonly changes from well to well. Thehydrodynamic connection commonly is absent even between neighboringproducing wells. Nevertheless, a limited number of wells have beenproducing hundreds of barrels of oil per day for more than 5 years.Maximum original yields of wells were as high as 40,000 b/d;however, in most cases yields decreased abruptly in a short periodof time, probably because of collapse of the reservoir rocks withdecreasing pressure (Nesterov and others, 1987). pag26 In comparison to that 40,000 BOPD figure from a vertical well, in2010 Brigham Exploration had announced that it had completed 39consecutive high-frac-stage long-lateral Bakken and Three Forkswells in North Dakota with an average early 24-hour peak flow backrate of approximately 2,777 barrels of oil equivalent. Can we quantify the potential? Let s assume that in that 800,000square kilometre sweet spot each square kilometre of BazhenovFormation averages 25 metres thick with a TOC of 10%. That amountsto 2.5 million cubic metres of organic carbon per square kilometre.If the yield to liquids is 30%, that amounts to 0.75 million cubicmetres or 4.7 million barrels. At 10% recovery, that in turn yields0.47 million barrels per square kilometre. The total for the sweetspot is thus 378 billion barrels, and there is possibly a third asmuch again outside the sweet spot. The central Bazhenov couldmaintain Russia s current production rate of about 10 million BOPDfor over 100 years. By comparison, the Canadian tar sands havereserves of the order of 177 billion barrels about half as much. What does this mean geopolitically? The very high tax rate on theRussian oil industry funds the Russian State and its adventuristpolicies. In 1904, J.H.Mackinder developed the heartland theory ingeopolitical analysis. In 1919, he summarised his theory as Whorules East Europe commands the Heartland; who rules the Heartlandcommands the World-Island; who rules the World-Island controls theworld. The sweetspot of the Bazhenov Formation is in the centre ofMackinder s pivot area, where the V of PIVOT is in the mapabove. The Bazhenov Formation will be literally fueling forays fromthe Heartland for decades to come. To the east of Russia, China hasabout one trillion tonnes of recoverable coal which could make 2trillion barrels of liquid fuels using the Fischer Tropsch process.To maintain comparative advantage against that combined flood offluid, a good nuclear technology will be required. I am an expert from uv-led-lights.com, while we provides the quality product, such as High Power UV Leds Manufacturer , Electrical Control Cabinets Manufacturer, DIP LED Lighting Source,and more.
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