000 02439nab a2200217 4500
005 20260608201746.0
008 260224s2016 xxu ing
041 _aInglés
100 1 _aFairbanks, Michael D.
_955392
100 1 _aRuppel, Stephen C.
_913376
100 1 _aRowe, Harry
_955393
245 0 0 _aHigh-resolution stratigraphy and facies architecture of the Upper Cretaceous (Cenomanian-Turonian) Eagle Ford Group, Central Texas
260 _a
_b
_cmar. 2016
270 _a06/06/2016 ; 06/06/2016
300 _a24 p. ; 379-403
520 _aTranscripción del resumen del autor: Rock-based studies of the Eagle Ford Group of Central Texas demonstrate that mudrock deposition is more complicated than previously supposed. X-ray diffraction, x-ray fluorescence, total organic carbon (TOC), and log data collected from eight cores and two outcrops demonstrate that bottom-current reworking and planktonic productivity are primary depositional controls, acting independently from eustatic forcing. Central Texas Eagle Ford facies include (1) massive argillaceous mudrock, (2) massive foraminiferal calcareous mudrock, (3) laminated calcareous foraminiferal lime mudstone, (4) laminated foraminiferal wackestone, (5) cross-laminated foraminiferal packstone-grainstone, (6) massive bentonitic claystone, and (7) nodular foraminiferal packstone-grainstone. High degrees of lateral facies variability, characterized by pinching and swelling of units, lateral facies changes, truncations, and locally restricted units, are observed even at small lateral scales (50 ft [15 m]). At 10 mi (16 km) and greater lateral spacings, core and geochemical data significantly underestimate intraformational facies variability. Approximately 73% of units can be successfully correlated across a distance of 500 ft (152 m), 35% are traceable across 1 mi (1.6 km), and only 16% of beds are correlative across 10 mi (16 km). Geochemical proxies (enrichment in molybdenum and other trace elements) indicate that maximum anoxia occurred within the Bouldin Member despite being composed of the most calcareous and high-energy facies. Comparison of total gamma ray (GR) logs to computed GR logs is requisite, because GR alone may provide misleading determination of facies, TOC content, depositional environment, and sequence stratigraphic implications.
581 _a3
773 _g
942 _cARTICULO
999 _c189582
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