Read subcritical propagation and coalescence of oil. Hydrocarbon generation induced microcracking of source rocks. Temperature increase is of primary importance for hydrocarbon generation. B g m 3 m 3 is the volume coefficient of natural gas.
Reservoir characteristics and potential evaluation of. Thermal maturation effects on the elastic properties of. Modeling maturation, elastic, and geomechanical properties. Modelling petroleum migration through microcrack propagation. 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. Burial history and catalytic effects, due to source rock matrix chemistry, affect the rate of generation, although these effects are secondary to the kinetic effects figure 1 shows hydrocarbon generation vs. Cap rocks presence to prevent the escape of petroleum fluids.
The depth of hydrocarbon generation and the yield of individual hydrocarbon phases are primarily a function of the kinetics of the kerogenhydrocarbon conversion. 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. Quantitative mineralogy and microfractures in the middle. Subcritical propagation of an oilfilled pennyshaped. Origin and evolution and prediction of porosity in clastic reservoir rocks j. Origin and evolution and prediction of porosity in clastic reservoir rocksj. Hydrocarbon generationinduced microcracking of source rocksj. American association of petroleum geologists bulletin, v. Abstract a technique allowing inversion of the shale stiffness tensor from standard logging data.
The rock has a very low permeability and porepressure buildup occurs. This understanding provides a framework for the safe extraction of hydrocarbons as well as a guide to mapp. The testing of the technique on laboratory measurements of the elastic wave velocities in shale samples shows that the inversion makes it possible to predict the elastic wave. The amount of burialinduced groundwater flow from the source rock. Hydrocarbon source rocks are critical elements of petroleum systems. This phenomenon occurs mainly in low permeability rocks e. 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. Hydrocarbongenerationinduced microcracking of source rocks. An analysis of horizontal microcracking during catagenesis. The time periods needed to build up the critical pressure are 22. Tertiary and upper cretaceous source rocks and the occurrences of oil and gas in the west central us. Nov 01, 2010 abstract a technique allowing inversion of the shale stiffness tensor from standard logging data.
Hydrocarbon generation an overview sciencedirect topics. Fracturing controlled primary migration of hydrocarbon. 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. Chapter 3 generation and expulsion of hydrocarbons sciencedirect. Ultrasonic velocity and anisotropy of hydrocarbon source. 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 1. The physics and efficiency of petroleum expulsion from coal.
The inversion is based on the effective medium theory. Hydrocarbon generationinduced 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. Petroleum phase state prediction in deep reservoir of. Rockphysics templates for hydrocarbon source rocks purdue math. Gasdriven subcritical crack propagation during the conversion of oil. Seismic data conditioning for avoaz analysis case study from a north kuwait unconventional reservoir. Subcritical propagation of an oilfilled pennyshaped crack. Oil generation requires productive source beds of high organic carbon content. By continuing to use our website, you are agreeing to our privacy policy. Controls of hydrocarbon generation on the development of. Apr 24, 2017 the preferred orientation of clay minerals dominates the intrinsic anisotropy of shale.
Pdf microfracturing during primary migration in shales. 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. Automated sourceedge location with a new variable passband horizontal. Rocky mountain association of geologists continuing education course notes. V g m 3 is the volume of free natural gas in source rocks. Hydrocarbon source rocks are laminated structures composed of kerogen, oil, water, and illite layers. Then, we perform the inversion of cl and the thomsen anisotropy parameters. The strong elastic anisotropy of tight, thermally mature source rocks is further enhanced by overpressureinduced beddingsubparallel microcrack development during the main stage of hydrocarbon hc generation and primary migration at. State key laboratory of shale oil and gas enrichment mechanisms and effective development, beijing 83, china. Determination of shale stiffness tensor from standard logs. Hydrocarbon generationinduced microcracking of source.
The source rock is described by a porous transversely isotropic medium composed of illitesmectite and organic matter. Feasibility of theoretical formulas on the anisotropy of. The direct measurement of anisotropy is difficult because of the. An interview with john logel february 2014 cseg recorder. Pdf geomechanical analysis of maturation for the draupne. Petroleum migration through microfracturing of the source rocks caused. Elastic properties of organic rich mudrocks are modeled as a function of thermal maturation. Source rocks are commonly shales and lime mudstones, which contain significant amount of organic matter 2. Anisotropy rock physics model for the longmaxi shale 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. Organicrich shales from the upper part of the fourth member and the lower part of the third member of the paleogene shahejie formation in the jiyang depression, bohai bay basin, east china, are used as an example. Kerogen maturation into oil and gas leads to a volume increase in the order of 1020% at 70. Petroleum phase state prediction in deep reservoir of tashen. Research conducted by vernik on petroleum source rocks vernik and. Landis 1996 elastic anisotropy of source rocksimplications for. The principal metamorphic stages of petroleum generation and a zone of initial oil source rock maturity are superimposed on graphs of lom versus depth for two wells to illustrate the prediction of.
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. Petroleum source rocks characterization and hydrocarbon. Commercial accumulations of oil and gas do not occur in source rocks, but in more. The preferred orientation of clay minerals dominates the intrinsic anisotropy of shale.
When the wavelength of the seismic pulse is much larger than the thickness of the single layers, the. Jan, 2010 1 we use a fracture mechanics model to study subcritical propagation and coalescence of single and collinear oil. A compressional wave seismic model for the ashrafi1 well. In addition, source rocks are important as unconventional hydrocarbon plays, i. Hydrocarbongenerationinduced microcracking of source rocks j. Fracturing controlled primary migration of hydrocarbon fluids during. Avo effects of a hydrocarbon sourcerock layer porosity. 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. A study of downhole electromagnetic sources for mapping enhanced oil recovery processes. Jan 01, 2010 read subcritical propagation and coalescence of oil.