Journal ArticleDOI
Sealing Properties of Tertiary Growth Faults, Texas Gulf Coast
TLDR
In this paper, the authors used Riedel shears on dip logs to detect growth faults and leak along the fault surface, which is a region of extension that is presumed to result in higher permeabilities, low displacement pressures, and the ability to transmit migrating oil and gas from deep source beds to shallow traps.Abstract:
Growth faults consist of nonsealing fault surfaces and sealing sheared zones that may occur on either the footwall or hanging wall. The properties of sheared zones are assumed to be identical to those of soft sediment that has undergone ductile deformation during mass movement. In cores, the sheared zones display fabrics similar to Riedel shears and are termed wispy, crenulate, conjugate, and meniscate, in order of increasing deformation. Permeabilities and porosities range from 0.1 md and 18% to less than 0.01 md and 8%. Based on limited measurements, initial mercury-injection capillary pressures range from 400 to 550 psia, sufficient to trap an average oil column of 98 m (320 ft). Sheared zones are effective seals because ductile deformation has homogenized the original sediments and resulted in a uniform distribution of small pores. In contrast, the fault surface is a region of extension that is presumed to result in higher permeabilities, low displacement pressures, and the ability to transmit migrating oil and gas from deep source beds to shallow traps. Thus, growth faults can seal in the sheared zone and leak along the fault surface. Sheared zones are distinctive on dip logs. Dips within sheared zones have variable magnitudes and directions, whereas dips adjacent to faults exhibit more uniform patterns resulting from normal drag.read more
Citations
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Journal ArticleDOI
Quantitative Fault Seal Prediction
TL;DR: In this article, the authors define two types of lithology-dependent attributes: gouge ratio and smear factor, and calibrate them in areas where across-fault pressure differences are explicitly known from wells on both sides of a fault.
Journal ArticleDOI
Fault sealing processes in siliciclastic sediments
Quentin J. Fisher,Rob J. Knipe +1 more
TL;DR: In this article, the microstructure and petrophysical properties of fault rocks from siliciclastic hydrocarbon reservoirs of the North Sea are closely related to the effective stress, temperature and sediment composition at the time of deformation, as well as their post-deformation stress and temperature history.
Journal ArticleDOI
Faulting, fault sealing and fluid flow in hydrocarbon reservoirs: an introduction
TL;DR: In this article, the effects of faults and fractures on fluid flow behavior and distribution within hydrocarbon provinces has become a priority, and a predictive knowledge of fault zone structure and transmissibility can have an enormous impact on the economic viability of exploration targets and generate considerable benefits during reservoir management.
Journal ArticleDOI
Cenozoic Qaidam basin, China: A stronger tectonic inversed, extensional rifted basin
TL;DR: The geologic history of the Cenozoic Qaidam basin can be divided into two megastages on the basis of stratigraphy and structure as discussed by the authors, which is demonstrated by two tectono-sequences formed by the rifting, the synrifting magmatic thermal activity, and the control of protobasin development by syndepositional faults.
Journal ArticleDOI
Basin-scale hydrogeologic modeling
TL;DR: In this paper, the authors present a review of the mathematical descriptions of basin transport processes, analytical and numerical solution methods employed, and the application of modeling to sedimentary basins around the world.
References
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Journal ArticleDOI
Role of fluid pressure in mechanics of overthrust faulting: I. Mechanics of fluid-filled porous solids and its application to overthrust faulting
M. King Hubbert,William W. Rubey +1 more
TL;DR: In this article, it was shown that the critical value of the shearing stress can be made arbitrarily small simply by increasing the fluid pressure p. This can be further simplified by expressing p in terms of S by means of the equation which, when introduced into equation (4), gives
Journal ArticleDOI
Similarities between Shear Zones of Different Magnitudes
TL;DR: In this article, an examination of the formation and development of shear zone structures on microscopic scale in the shear box test, intermediate scale in Riedel experiment, and regional scale in earthquake fault is made.
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Relationship of porosity and permeability to various parameters derived from mercury injection-capillary pressure curves for sandstone
TL;DR: In this paper, the relationship of porosity, uncorrected air permeability, and various parameters derived from mercury injection-capillary pressure curves was established using multiple regression on a database of 202 samples of sandstone from 14 formations that range in age from Ordovician to Tertiary.
Journal ArticleDOI
Effect of Faulting on Fluid Flow in Porous Sandstones: Petrophysical Properties
Marco Antonellini,Atilla Aydin +1 more
TL;DR: In this article, the authors quantified fault zone permeability in outcrop by detailed geologic mapping and by measurements using a minipermeameter, and found that deformation bands have porosity about one order of magnitude less than the surrounding host rock.
Journal ArticleDOI
A Simple Correlation Between Permeabilities and Mercury Capillary Pressures
TL;DR: In this paper, a new correlation between brine and air permeabilities with capillary pressure data is developed, which offers ready application to improved estimation of brine permeability from measurements on small portions of sidewall core samples and drill cuttings.