American association of petroleum geologists bulletin, v. When the wavelength of the seismic pulse is much larger than the thickness of the single layers, the. 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. Ultrasonic velocity and anisotropy of hydrocarbon source. Porous flow is an unsatisfactory explanation for migration of oil out of these extremely low.
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. A compressional wave seismic model for the ashrafi1 well. The rock has a very low permeability and porepressure buildup occurs. Anisotropy rock physics model for the longmaxi shale gas. State key laboratory of shale oil and gas enrichment mechanisms and effective development, beijing 83, china. 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. Research highlights we show a basin evolution model of a source rock volume at constant sedimentation rate and geothermal gradient. Then, we perform the inversion of cl and the thomsen anisotropy parameters. Feasibility of theoretical formulas on the anisotropy of. Orthotropic rockphysics based inversion for fracture and total organic carbon toc characterization from azimuthal pwave seismic survey. 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. Chapter 3 generation and expulsion of hydrocarbons.
The depth of hydrocarbon generation and the yield of individual hydrocarbon phases are primarily a function of the kinetics of the kerogenhydrocarbon conversion. The medium source rocks in the sha 3 member account for 2. Jan 01, 2010 read subcritical propagation and coalescence of oil. Case study from a northern kuwait unconventional reservoir. Reservoir characteristics and potential evaluation of. Hydrocarbon source rocks are laminated structures composed of kerogen, oil, water, and illite layers. 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. Subcritical propagation of an oilfilled pennyshaped crack. Origin and evolution and prediction of porosity in clastic reservoir rocksj. Considering the monterey and northsea kimmeridge shales we obtain the increase in pressure due to oil generation from kerogen. Read subcritical propagation and coalescence of oil. Vernikhydrocarbon generationinduced microcracking of source rocks and their seismic detection. Hydrocarbon generationinduced microcracking of source rocksj. Rocky mountain association of geologists continuing education course notes.
Petroleum phase state prediction in deep reservoir of tashen. 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. A study of downhole electromagnetic sources for mapping enhanced oil recovery processes. 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. 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. Apr 24, 2017 the preferred orientation of clay minerals dominates the intrinsic anisotropy of shale. Sagnik dasgupta, colin sayers, peck hwa david ng, andrew hannan, edan gofer, andy walz, and chuck wagner, schlumberger. Mackenzie and quigley 1988 oil prone source rock at depths of 3 4 km,the oily hydrocarbons must displace groundwater. Landis 1996 elastic anisotropy of source rocksimplications for. Estimates of reservoir properties such as porosity, toc content, clay content, fluid saturation, and fracture intensity are required for understanding unconventional reservoirs. 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. Pdf geomechanical analysis of maturation for the draupne. The oil bearing nkp formation at ashrafi1 shows district bright amplitude and avo class 34 response.
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. We use gassmanns equations generalized to the anisotropic case. Modelling petroleum migration through microcrack propagation. These points can easily be distinguished from background. Avo effects of a hydrocarbon sourcerock layer porosity. Hydrocarbongenerationinduced microcracking of source rocks. 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. By continuing to use our website, you are agreeing to our privacy policy. Subcritical propagation of an oilfilled pennyshaped. U1663207, and the national natural science foundation of china no. Microfracturing and microporosity in shales, earthscience. The time periods needed to build up the critical pressure are 22. 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.
Jan, 2010 1 we use a fracture mechanics model to study subcritical propagation and coalescence of single and collinear oil. The organic mater was deposited in a marine environment and remained buried under anoxic conditions for 100400 millions years. The source rock is described by a porous transversely isotropic medium composed of illitesmectite and organic matter. A petroleum source rock is defined as any rock that has the capability to generate. Oil generation requires productive source beds of high organic carbon content. We obtain the seismic velocities of the source rock as a function of. 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. Vernik l 1994 hydrocarbon generationinduced microcracking of source rocks geophysics 59 55563 crossref vernik l and landis c 1996 elastic anisotropy of source rocks. Models constructed incorporate organic nanopores filled with hydrocarbons, and the alteration of the remaining kerogen solids. The research is supported by the foundation of state key laboratory of shale oil and gas enrichment mechanisms and effective development no.
Tertiary and upper cretaceous source rocks and the occurrences of oil and gas in the west central us. Source rocks are commonly shales and lime mudstones, which contain significant amount of organic matter. 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. Automated sourceedge location with a new variable passband horizontal. G580016zskfzy002, the nsfc and sinopec joint key project no. The direct measurement of anisotropy is difficult because of the. Hydrocarbon generation induced microcracking of source rocks. Hydrocarbon generation an overview sciencedirect topics. The porosity and toc content help to explain the reservoir quality. Elastic properties of organic rich mudrocks are modeled as a function of thermal maturation. 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. Thermal maturation effects on the elastic properties of.
Petroleum phase state prediction in deep reservoir of. Western siberia hydrocarbon exploration spectral density. The increase of pressure and temperature slowly transformed the organic matter into hydrocarbons kerogen, oil, gas. Cap rocks presence to prevent the escape of petroleum fluids. Quantitative mineralogy and microfractures in the middle. Orthotropic rockphysics based inversion for fracture and.