Browsing by Subject "Fort Worth Foreland Basin"

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Upper Desmoinesian-Lower Missourian depositional systems (Pennsylvanian), North-Central Texas
(1975) Cleaves, A. W. (Arthur Wordsworth); Not available
Fluvial and deltaic facies comprising the upper part of the Strawn Group were deposited within the Fort Worth Foreland Basin and on the adjacent Concho Platform of North-Central Texas. Variations in the rates of subsidence in the basin and on the platform led to the development of distinctive sandstone geometry, facies distribution patterns, and sandstone thicknesses. Seven cycles of delta progradation and abandonment have been delineated; 3,500 wells and surface measured sections served as the principal sources of data. Both high-constructive elongate and lobate deltaic facies have been recognized. The most significant source areas for terrigenous clastic debris include the Arbuckle Mountains of Oklahoma and the Ouachita Fold Belt of Texas. When subsidence decreased within the Fort Worth Basin during the Desmoinesian Epoch, deltas of the Strawn Group prograded across the filled foreland basin and onto the slowly subsiding Concho Platform. Deltaic facies deposited on the platform comprise thin (less than 200 feet thick), multilateral lobate and elongate delta systems. A typical vertical sequence of facies includes (upwards) prodelta mudstone, delta-front sheet sandstone, channel-mouth bar sandstone, distributary channel-fill sandstone, and delta plain mudstone. Initial deltas prograded to the western margin of the Concho Platform; the Midland Basin to the west was poorly defined and no true shelf-edge or slope facies of Desmoinesian age have been recognized in this area. High-constructive elongate delta systems greater than 200 feet thick were deposited in the northwestern end of the Fort Worth Basin during periods of active subsidence up to the end of the Desmoinesian. These thicker deltas are characterized by linear, multistory sandstone bodies that resemble barfinger sands of the Holocene Mississippi Delta. Incised, valley-fill fluvial deposits commonly overlie the high-constructive deltaic facies