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Showing 1 to 20 of 50 for “"Lowstand"”.
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Updip Sequence Development on a Mixed Carbonate-Siliciclastic Continental Shelf, Paleogene, North Carolina, Eastern U.S.A.
… bounded by hardgrounds, overlain by thin local lowstand sands and consist of a thin transgressive unit (commonly absent), overlain by an upward shallowing highstand marine succession. On the arch, lowstand and transgressive units may be condensed into lags. The Lower Oligocene succession on the …
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High-Resolution Sequence Stratigraphy of Paleogene, Nontropical Mixed Carbonate/Siliciclastic Shelf Sediments, North Carolina Coastal Plain, U. S. A.
… The Eocene supersequence developed following lowstand deposition (evident on seismic) just off the terminal Paleocene depositional shelf break. With flooding, a major transgressive sediment body developed (Pamlico spur), that formed a 50 km wide by 50 m high promontory at the inner shelf …
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Regional stratigraphy of the Newcastle Formation (Lower Cretaceous) in eastern Montana and western North Dakota
… Montana. This work also illustrates the possible lowstand position of the Western Interior Seaway along with probable source areas providing sediments into the study area. </p><p> A total of 3446 geophysical wireline logs were used to determine formation tops of the Greenhorn, Mowry, Newcastle, …
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Stratigraphy, Petrology, Diagenesis, Paleontology, and Depositional Environments of the Harrisburg Member of the Kaibab Formation in Northern Arizona and Southern Utah
… of unit three was subaerially exposed during a lowstand systems tract creating sequence boundary one. Sequence two consists of units four through nine which represent a transgressive stems tract. The Permian-Triassic unconformity above the Harrisburg Member represents a forced regression and …
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SEDIMENTOLOGY, ICHNOLOGY, AND SEQUENCE STRATIGRAPHY OF THE MIOCENE OFICINA FORMATION, ORINOCO OIL BELT, EASTERN VENEZUELA BASIN
… and Upper. The Lower Member consists mainly of lowstand fluvial braidedchannel deposits filling an incised valley. No evidence of marine conditions is present and the only biogenic structures detected are root trace fossils present at the top of a few fining- and thinning- upward channelized …
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Architectural Models for Lower Pennsylvanian Strata in Dickenson/Wise County, Southwest Virginia: A Reservior Case Study
… discontinuities and consist of upward-fining lowstand and transgressive incised valley fill, alluvial, and estuarine deposits, and upward-coarsening highstand deltaic deposits and represent 4th-order sequences. Lowstand and transgressive deposits are separated from the highstand deposits by …
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State-Wide Sequence Framework of Mixed Carbonate-Siliciclastic Ramp Reservoirs: Mississippian Big Lime, West Virginia, USA
… as isopachs maps of the sequences, and of lowstand-transgressive, and highstand tracts with major facies shown. This data was then used to document the stratigraphic response of the foreland basin to tectonics and, with isotope data from the slope section, evaluates evidence for …
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Reservoir characterization and prediction of the Lower Cretaceous Glauconite Member at Jenner-Suffield Field, Alberta, Canada.
… sea level rise following an episode of lowstand paleovalley incisement. Borehole data were used to identify petrofacies within the Glauconitic Member and characterize their controls on reservoir quality, production characteristics, and petrophysical attributes for facies prediction. …
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Late Quaternary marine deposits, offshore central Texas: Processes controlling geometry, distribution, and preservation potential
… Fluvial incision varied significantly during lowstand Stage 2. As the rate of base-level fall increased from Stage 3 to 2, low sediment supply rivers incised narrow, shallow channels with no deltaic deposition, whearas sediment bypass and deeper incision prevailed for the high sediment supply …
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High resolution sequence stratigraphy of late Mississippian carbonates in the Appalachian Basin
… and shoal water facies on the ramp, and beneath lowstand sand bodies and quartzose calcisiltite wedges on the ramp margin and slope. Maximum flooding surfaces are difficult to map regionally, therefore it is difficult to separate the TST from the HST of these fourth-order sequences.
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Stratigraphy of the mid-Carboniferous boundary
… interval, there is a geochemical expression of a lowstand during the lowest Chokierian. Additionally, doubt is cast on the presumption that all sediments deposited outside 'marine bands' are non marine. A model has been developed for mid-Carboniferous deposition in the Clare Basin. It is envisaged …
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Late Quaternary Louisiana Shelf-Margin Deltaic Deposition, North-Central Gulf of Mexico
… shelf-margin deltaic deposition during the last lowstand of sea level (~18, 000 yrs BP), sourced by the Pearl River. .
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Algal and protozoan response to Holocene climate change and anthropogenic impact: a case study from Sluice Pond, MA
… only became abundant when the drought-induced lowstand oxygenated the bottom waters. Protozoans tolerant of low DO became abundant through the late Holocene as water levels rose and cultural eutrophication produced a sharp increase in biochemical oxygen demand (BOD) beginning in the 17th …
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The marine geology of Mossel Bay, South Africa
… MIS 5 interglacial periods and include incised lowstand river channels and regressive aeolianites that extended at least 10 km inland from their associated palaeoshorelines. The MIS 5 deposits include transgressive beachrock, an extensive foreshore unit which prograded on the MIS 5e highstand, …
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Sequence Development on a Sediment-Starved, Low Accommodation Epeiric Carbonate Ramp: Silurian Wabash Platform, USA Mid-continent During Icehouse to Greenhouse Transition
… that the correlative conformities are cryptic. Lowstand system tracts probably include downdip grainy facies and the deep ramp seaward of updip late highstand deposits. Transgressive systems tracts are upward deepening, upward fining carbonate units, some of which become more argillaceous and …
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Sedimentological lithofacies, internal architecture and evolution of deep marine fans of the Tithonian Angel Formation, Northwestern Dampier Sub-basin, North West Shelf, Australia.
… models are related to early and late lowstand time. Stacked fifth order architectures deposited during sixth order progradational cycles display high net to gross sandstones, low channel sinuousity and increased amalgamation of channel forms. Sixth order aggradational and …
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Magnetic Characteristics of Carboniferous Continental Depositional Systems: Implications for the Recognition of Depositional Hiatuses
… that may correlative with incised valleys (lowstand surface of erosion). Similarly, in lower Pennsylvanian quartz arenite facies, early siderite cementation zones as well as conglomerate lags with distinctive magnetic characteristics are thought to reflect periods of prolonged exposure and …
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Identification of the physical controls on the deposition of Aptian and Albian deep water sands in the Bredasdorp Basin, South Africa
… it hosts world class outcrops of deep water lowstand fan deposits and therefore shows the finer-scale details of the associated depositional stratigraphy. The 13A and 14A sequence sands would have entered the Bredasdorp Basin in progradational pulses alternating with mud-rich successions …
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GEOCHEMICAL CHARACTERIZATION OF THE BONE SPRING FORMATION, DELAWARE BASIN, USING CHEMOSTRATIGRAPHY AND INTEGRATED PETROPHYSICS
… which can largely be correlated to highstand and lowstand systems tracts, respectively. Lithological complexity and facies change are manifested by debris flows, turbidites, and slumps. In addition to glacio-eustasy, both tectonism and broader Milankovitch cycles have influenced the depositional …
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Sequence Stratigraphy of the Bridal Veil Falls Limestone, Carboniferous, Lower Oquirrh Group, on Cascade Mountain, Utah: A standard Morrowan Cyclostratigraphy for the Oquirrh Basin
… (located to the NE) during episodes of sea-level lowstand. The Bridal Veil Falls Limestone is subdivided into 21, third and fourth order depositional sequences ranging in thickness from 3 to 60 meters, and 62 parasequences. Parasequences are commonly asymmetrical, reflecting rapid flooding …
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