Jan 01, 2010 read subcritical propagation and coalescence of oil. Research highlights we show a basin evolution model of a source rock volume at constant sedimentation rate and geothermal gradient. Moreover, when they contain organic matter, they form source rocks for hydrocarbons that may escape towards a more porous reservoir during burial, a process referred to. Oil generation requires productive source beds of high organic carbon content. In source rocks with a good oil potential, the oil saturation of the pore system will reach higher values more quickly during burial than in source rocks with a poor oil calculated that in a rich potential durand, 1983.
By continuing to use our website, you are agreeing to our privacy policy. The organic mater was deposited in a marine environment and remained buried under anoxic conditions for 100400 millions years. Microfracturing and microporosity in shales, earthscience. G580016zskfzy002, the nsfc and sinopec joint key project no. The depth of hydrocarbon generation and the yield of individual hydrocarbon phases are primarily a function of the kinetics of the kerogenhydrocarbon conversion. Quantitative mineralogy and microfractures in the middle. Apr 24, 2017 the preferred orientation of clay minerals dominates the intrinsic anisotropy of shale. John, in your article you touch upon a very interesting aspect of learning in that if the concepts of science that we practice are explained in a simple. Estimates of reservoir properties such as porosity, toc content, clay content, fluid saturation, and fracture intensity are required for understanding unconventional reservoirs. An interview with john logel february 2014 cseg recorder.
A study of downhole electromagnetic sources for mapping enhanced oil recovery processes. Petroleum source rock is defined as the finegrained sediment with sufficient amount of organic matter, which can generate and release enough hydrocarbons to form a commercial accumulation of oil or gas. Petroleum migration through microfracturing of the source rocks caused mainly by oil gas generation is cited as an effective mechanism for primary migration at great depths e. Anisotropy rock physics model for the longmaxi shale gas. Nov 01, 2016 shales are ubiquitous rocks in sedimentary basins, where their low permeability makes them efficient seals for conventional oil and gas reservoirs and underground waste storage repositories waste waters, co2, nuclear fuels. Elastic properties of organic rich mudrocks are modeled as a function of thermal maturation. Vernik l 1994 hydrocarbon generationinduced microcracking of source rocks geophysics 59 55563 crossref vernik l and landis c 1996 elastic anisotropy of source rocks. Ultrasonic velocity and anisotropy of hydrocarbon source. Petroleum source rocks characterization and hydrocarbon.
Vernikhydrocarbon generationinduced microcracking of source rocks and their seismic detection 62nd annual international meeting of society of exploration geophysicists, expanded abstracts 1992, pp. The subcritical propagation distance, propagation duration, crack coalescence and excess oil pressure in the crack are determined using the fracture mechanics model together with the kinetics of kerogen. Reservoir characteristics and potential evaluation of. Petroleum phase state prediction in deep reservoir of. Petroleum phase state prediction in deep reservoir of tashen. We obtain the seismic velocities of the source rock as a function of. Hydrocarbon source rocks are laminated structures composed of kerogen, oil, water, and illite layers. Case study from a northern kuwait unconventional reservoir. Considering the monterey and northsea kimmeridge shales we obtain the increase in pressure due to oil generation from kerogen. Orthotropic rockphysics based inversion for fracture and. Chapter 3 generation and expulsion of hydrocarbons.
Modelling petroleum migration through microcrack propagation. Shales are ubiquitous rocks in sedimentary basins, where their low permeability makes them efficient seals for conventional oil and gas reservoirs and underground waste storage repositories waste waters, co2, nuclear fuels. Source rocks are commonly shales and lime mudstones, which contain significant amount of organic matter. We introduce the clay lamination cl parameter to the backus averaging method to describe the intrinsic shale anisotropy induced by the alignment of clay minerals. Jan, 2010 1 we use a fracture mechanics model to study subcritical propagation and coalescence of single and collinear oil. The porosity and toc content help to explain the reservoir quality. Thermal maturation effects on the elastic properties of. The preferred orientation of clay minerals dominates the intrinsic anisotropy of shale. Landis 1996 elastic anisotropy of source rocksimplications for. Introduction 2 black shales commonly contain significant volume fractions of kerogen, which transforms to oil andor gas under appropriate temperature and pressure conditions. Feasibility of theoretical formulas on the anisotropy of. We use gassmanns equations generalized to the anisotropic case. The direct measurement of anisotropy is difficult because of the. U1663207, and the national natural science foundation of china no.
The source rock is described by a porous transversely isotropic medium composed of illitesmectite and organic matter. When the wavelength of the seismic pulse is much larger than the thickness of the single layers, the. Rocky mountain association of geologists continuing education course notes. A petroleum source rock is defined as any rock that has the capability to generate. Tertiary and upper cretaceous source rocks and the occurrences of oil and gas in the west central us. Models constructed incorporate organic nanopores filled with hydrocarbons, and the alteration of the remaining kerogen solids. Subcritical propagation of an oilfilled pennyshaped. Automated sourceedge location with a new variable passband horizontal. This source bed will be able to generate petroleum over a long period of time in which the beds are exposed to 3 stages of transformation. Hydrocarbongenerationinduced microcracking of source rocks. The medium source rocks in the sha 3 member account for 2. To investigate primary petroleum migration through microfracturing of source rocks, we develop a theoretical multiphysics model incorporating simultaneous generation of oil and gas from kerogen, elastic anisotropy of the source rock and propagation of microcracks filled with oil and gas. Hydrocarbon generation induced microcracking of source rocks.
The aim of this work is to obtain a model for source rocks relating to kerogen oil conversion and pore pressure to seismic velocity and anisotropy. Hydrocarbon generationinduced microcracking of source rocksj. These points can easily be distinguished from background. Subcritical propagation of an oilfilled pennyshaped crack. Porous flow is an unsatisfactory explanation for migration of oil out of these extremely low. The time periods needed to build up the critical pressure are 22. Vernikhydrocarbon generationinduced microcracking of source rocks and their seismic detection. John, in your article you touch upon a very interesting aspect of learning in that if the concepts of science that we practice are explained in a simple way, they can be grasped easily by the listeners. Sagnik dasgupta, colin sayers, peck hwa david ng, andrew hannan, edan gofer, andy walz, and chuck wagner, schlumberger. The properties of the kerogen oil water mixture are obtained with the kuster and toksoz model, assuming that oil and water are the inclusion in. Read subcritical propagation and coalescence of oil. Avo effects of a hydrocarbon sourcerock layer porosity. Pdf geomechanical analysis of maturation for the draupne.
The increase of pressure and temperature slowly transformed the organic matter into hydrocarbons kerogen, oil, gas. The oil bearing nkp formation at ashrafi1 shows district bright amplitude and avo class 34 response. Mackenzie and quigley 1988 oil prone source rock at depths of 3 4 km,the oily hydrocarbons must displace groundwater. The rock has a very low permeability and porepressure buildup occurs. The research is supported by the foundation of state key laboratory of shale oil and gas enrichment mechanisms and effective development no. Orthotropic rockphysics based inversion for fracture and total organic carbon toc characterization from azimuthal pwave seismic survey. A compressional wave seismic model for the ashrafi1 well. Hydrocarbon generation an overview sciencedirect topics. American association of petroleum geologists bulletin, v. Origin and evolution and prediction of porosity in clastic reservoir rocksj.
1437 1489 44 674 126 314 944 864 1208 1326 1249 223 324 437 828 419 1347 123 1242 740 1410 1518 785 1159 323 1369 394 270 543 232 183 1175 1468 1469