Filters: Tags: sequence stratigraphy (X)
6 results (43ms)
Filters
Date Range
Extensions Types Contacts
Categories Tag Types Tag Schemes |
High-frequency stratigraphic sequences that comprise the Desert Member of the Blackhawk Formation, the Lower Castlegate Sandstone, and the Buck Tongue in the Green River area of Utah display changes in sequence architecture from marine deposits to marginal marine deposits to an entirely nonmarine section. Facies and sequence architecture differ above and below the regionally extensive Castlegate sequence boundary, which separates two low-frequency (106-year cyclicity) sequences. Below this surface, high-frequency sequences are identified and interpreted as comprising the highstand systems tract of the low-frequency Blackhawk sequence. Each high-frequency sequence has a local incised valley system on top of the wave-dominated...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Blackhawk Formation,
Castlegate Sandstone,
Sedimentary Geology,
basement,
facies,
The Campanian Cliff House Formation represents a series of individually progradational shoreface tongues preserved in an overall landward-stepping system. In the Mancos Canyon area, the formation consists of four, 50- to 55-m-thick and 10- to 20-km-wide sandstone tongues, which pinch out landwards into lower coastal plain and lagoonal deposits of the Upper Menefee Formation and seawards into offshore shales of the Lewis Shale Formation. Photogrammetric mapping of lithofacies along the steep and well-exposed canyon walls was combined with sedimentary facies analysis and mapping of the detailed facies architecture. Two major facies associations have been identified, one comprising the mostly muddy and organic-rich...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Cliff House Formation,
Sedimentology,
facies architecture,
geometry,
landward-stepping shoreface tongues,
The lower part of the Campanian Castlegate Formation, one of the best known fluvial sheet sands of the Western Interior seaway, combines with an overlying finer grained unit (middle member of the Castlegate Formation) to form an unconformity-bounded, third-order stratigraphic sequence ([~]3 m.y. duration). This sequence contains a mappable muddy zone along the western Book Cliffs of Utah now mapped as contiguous with the open-marine parts of the succession (Buck Tongue, Sego Sandstone, Anchor Mine Tongue) to the east. The correlation within the middle Castlegate has been refined and the nature of the link between tidally influenced fluvial strata in the west and marine strata in the east has been remapped. Five...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Book Cliffs,
Castlegate,
Geology,
nonmarine,
sequence stratigraphy
This geologic map and report present 1:63,360-scale geologic mapping of the south-central Sagavanirktok Quadrangle in northern Alaska. This area encompasses approximately 600 square miles in the northern foothills of the Brooks Range, and includes stratigraphic and structural elements important to understanding the oil and gas potential of Alaska's North Slope.
Two members of the Green River Formation in the Washakie Basin have been analysed by organic geochemical and organic petrographic techniques and the results placed in a sequence stratigraphic framework. One of these members, the Laney Shale, was deposited in a hydrologically closed, alkaline lake under an arid climate and was characterized by high concentrations of alginite-rich organic matter whereas the other, the Luman Tongue, was deposited in a hydrologically open, freshwater lake under a humid climate and consisted of organic-poor profundal lake mudstones and coaly lake margin sediments. Potential source rocks in both lake types have the potential for generating high-wax oil at high subsurface temperatures...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: 4-methylsteroids,
Organic Geochemistry,
alkaline/freshwater lakes,
green river formation,
high-wax crude oil,
Integrated fluvial sequence stratigraphic and palaeosol analysis can be used to better reconstruct depositional systems, but these approaches have not been combined to examine halokinetic minibasins. This study characterizes the temporal and spatial patterns of lithofacies and palaeosols in a sequence stratigraphic framework to reconstruct a model of minibasin evolution and identify halokinetic influences on fluvial deposition. This research documents fluvial cycles and stratigraphic hierarchy, palaeosol maturity and apparent sediment accumulation rates in the Chinle Formation within the Big Bend minibasin. This study also uses palaeosols to help identify fluvial aggradational cycle (FAC) sets. The Chinle is divided...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Halokinesis,
Paradox Basin,
Sedimentology,
minibasin,
palaeopedology,
|
|