Author: Thomas Edward EwingPublisher:
ISBN:
Category : Coastal plains
Languages : en
Pages : 286
Book Description
Structural Styles of the Wilcox and Frio Growth-fault Trends in Texas
Author: Thomas Edward EwingPublisher:
ISBN:
Category : Coastal plains
Languages : en
Pages : 286
Book Description
Structural Styles of the Wilcox and Frio Growth-fault Trends in Texas
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The wide variability in structural styles within the growth-faulted, geopressured trends of the Texas Gulf Coast is illustrated by detailed structural maps of selected areas of the Wilcox and Frio growth-fault trends and quantified by statistical analysis of fault compartment geometries. Structural variability is a key determinant of the size of geopressured aquifers in the deep subsurface. Two major structural styles exist in the Wilcox trend. (1) In southeast and Central Texas, the trend consists of continuous, closely spaced faults that have little associated rollover despite moderate expansion of section; the fault plane flattens little with depth. (2) By contrast, in South Texas a narrow band of growth faults having high expansion and moderate rollover lies above and downdip of a ridge of deformed, overpressured shale but updip of a deep basin formed by withdrawal of overpressured shale. Frio fault systems generally display greater rollover and wider spacing than do Wilcox fault systems; however, the Frio trend displays distinctive features in each study area. Most of the Frio growth faults, however, have a similar geometry, showing substantial rollover, expansion of section, and a moderate flattening of the fault zone with depth, possibly related to a deep decollement surface. The local variability in style is related to the magnitude of Frio sedimentation and progradation and to the presence of thick salt or shale. Finding and developing a large geopressured aquifer require recognition of a favorable combination of sand-body geometry, reservoir quality, and fault compartment size and shape.
Depositional Setting, Structural Style, and Sandstone Distribution in Three Geopressured Geothermal Areas, Texas Gulf Coast
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Three areas in the Texas Gulf Coastal Plain were studied using electric logs and seismic-reflection data to interpret their depositional and structural history and to compare their potential as geopressured-geothermal reservoirs. The Cuero study area, on the lower Wilcox (upper Paleocene) growth-fault trend, is characterized by closely and evenly spaced, subparallel, down-to-the-basin growth faults, relatively small expansion ratios, and minor block rotation. Distributary-channel sandstones in the geopressured lower Wilcox Group of the South Cook fault block appear to be the best geothermal aquifers in the Cuero area. The Blessing study area, on the lower Frio (Oligocene) growth-fault trend, shows wider and more variable fault spacing and much greater expansion ratios and block rotation, particularly during early Frio time. Thick geopressured sandstone aquifers are laterally more extensive in the Blessing area than in the Cuero area. The Pleasant Bayou study area, like the Blessing area, is on the Frio growth-fault trand, and its early structural development was similar rapid movement of widely spaced faults resulted in large expansion ratios and major block rotation. However, a late-stage pattern of salt uplift and withdrawal complicated the structural style. Thick geopressured lower Frio sandstone aquifers are highly permeable and laterally extensive, as in the Blessing area. In all three areas, geopressured aquifers were created where early, rapid movement along down-to-the-basin growth faults juxtaposed shallow-water sands against older shales, probably deposited in slope environments. Major transgressions followed the deposition of reservoir sands and probably also influenced the hydraulic isolation that allowed the build up of abnormal pressures. 26 refs., 49 figs., 8 tabs.
Energy Research Abstracts
Author: Texas State Documents
Author: Texas State Publications ClearinghousePublisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1036
Book Description
Shale Tectonics
Author: Lesli J. WoodPublisher: AAPG
ISBN: 0891813756
Category : Science
Languages : en
Pages : 242
Book Description
Hardcover plus CD
Report of Investigations
Author: Frio Formation of the Texas Gulf Coast Basin
Author: William E. GallowayPublisher:
ISBN:
Category : Frio Clay (Tex. and La.).
Languages : en
Pages : 108
Book Description
Geology of North America—An Overview
Author: Albert W. BallyPublisher: Geological Society of America
ISBN: 0813754453
Category : Science
Languages : en
Pages : 633
Book Description
Summaries of the major features of the geology of North America and the adjacent oceanic regions are presented in 20 chapters. Topics covered include concise reviews of current thinking about Precambrian basement, Phanerozoic orogens, cratonic basins, passive-margin geology of the Atlantic and Gulf Coast regions, marine and terrestrial geology of the Caribbean region and economic geology.
Author: