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Showing 1 to 20 of 26 for “"Sequence boundaries"”.
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Valley Widening and the Composite Nature of Valley Margin Sequence Boundaries: Evidence from the Neilson Wash Compound Valley Fill, Cretaceous Ferron Sandstone, Utah
… are at the center of a debate about whether sequence boundaries are chronostratigraphically significant. Current research has suggested that the sequence boundary that makes up the floor and walls of an incised valley is constantly being modified throughout the entire relative sea-level …
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The Lower Pennsylvanian New River Formation: a Nonmarine Record of Glacioeustasy in a Foreland Basin
… River Formation (NRF) are poorly understood. A sequence stratigraphic framework for the NRF, based on a combination of outcrop mapping and subsurface well-log analysis, reveals: 1) regionally significant erosional surfaces along the bases of sheet-like and channel-like sandstone bodies …
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Offshore El Salvador: the first interpretation of a unique 2-D seismic dataset and implications for a working petroleum system in a forearc basin setting
… Cenozoic sediments. In the Acajutla basin, seven sequence boundaries have been identified that are continuous and display high to moderate reflective amplitudes, encompassing Late Cretaceous through Pleistocene intervals. Structure contour and isochron maps are generated on mapped sequence …
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Mixed Carbonate-Siliciclastic Sequence Development and Chemostratigraphy On a Distal Foreland During Miocene Glaciation, Eastern Saudi Arabia
… deposition under semi-arid climate. Sequences appear to relate to long-term obliquity (~1.2 m.y. cycles) and long-term eccentricity (400 k.y.) cycles. The succession contains numerous missing beats reflecting the updip position of the study area, and sea level changes of tens of …
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High resolution sequence stratigraphy of late Mississippian carbonates in the Appalachian Basin
… transgression that formed the Mississippian supersequence. The St. Louis- to Glen Dean interval consists of up to twelve fourth-order depositional sequences (300 to 400 k.y. average duration). The sequences (a few meters to over a hundred meters thick) consist of eolianites, lagoonal carbonate …
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Transitional Facies and Sequence Stratigraphic Complexity of Shallow-Marine Star Point Formation to Coastal-Plain Blackhawk Formation Along Depositional-Strike, Wasatch Plateau, Utah
… dip-oriented outcrops show pinch-outs of two parasequences into coastal-plain deposits. This complexity decreases southward, the southern outcrops show a simple transition. At least two sequence boundaries are correlated across the outcrop belt.</p>
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Dinoflagellate paleoecology and biostratigraphy of the Middle Eocene Tallahatta and Lisbon Formations from the Baldwin County, Alabama, Core
… project being conducted by the ARCO Depositional Sequence Analysis Group to gather paleontological, sedimentological, paleomagnetic, geophysical, and geochemical data from the Alabama Coastal Plain for the purpose of calibrating the Tertiary time scale with the sequence stratigraphy of the Gulf …
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Sequence Stratigraphy of Middle-Mississippian Carbonates of the Southern Appalachians: Tuscumbia Limestone, Tuscumbia, AL
<p>This field-based research develops a sequence stratigraphic framework and detailed facies analysis which is used as a basis for understanding depositional histories of low-latitude, shallow-water, Mississippian carbonate deposits (Fort Payne Chert and Tuscumbia Limestone) in northwestern …
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Depositional systems, sequence architecture, and controlling factors of an Eocene stratigraphic sequence at Minfeng steep margin of Dongying depression, eastern China
… interpret the depositional systems, reconstruct sequence stratigraphic architecture, and understand the controlling processes and factors at the steep margin of a rift basin. In the first part of this work, an Eocene stratigraphic sequence is divided into three systems tracts, corresponding to …
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Late Quaternary Evolution and Stratigraphic Framework Influence on Coastal Systems along the North-Central Gulf of Mexico, USA
… and 63 radiocarbon dates to regionally map two sequence boundaries, multiple ravinement surfaces and fourteen depositional facies. One marine isotope stage (MIS) 6 valley’s fill provided up to 300 x10<sup>6</sup> m<sup>3 </sup>of sand to modern systems through transgressive ravinement during the …
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Seismic sequence stratigraphy of the Lower Congo, Kwanza, and Benguela Basins, offshore Angola, Africa
Sequences are recognized throughout the geologic record. The Angolan margin provides an excellent opportunity to examine the factors that control the deposition and preservation of sediments in sequences, as well as the factors that create the erosion or non-deposition along sequence boundaries. …
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Evolution and Architecture of an Incised Valley in the Upper Cretaceous Eagle Formation in South-Central Montana
… the regressive surface of marine erosion (RSE), sequence boundary (SB), and transgressive surface of tidal-fluvial erosion (TSE). Within this sequence stratigraphic framework, 4 facies association, internal lower-order architectures (i.e. channel forms, lateral accretion sets, crevasse splays) …
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Evolution and Architecture of an Incised Valley in the Upper Cretaceous Eagle Formation in South-Central Montana
… the regressive surface of marine erosion (RSE), sequence boundary (SB), and transgressive surface of tidal-fluvial erosion (TSE). Within this sequence stratigraphic framework, 4 facies association, internal lower-order architectures (i.e. channel forms, lateral accretion sets, crevasse splays) …
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Climatic and tectonic controls on deep water sedimentary cyclicity : evidence from the Miocene to Pleistocene of Cyprus
… the formation can be divided into depositional sequences,bounded by hard grounds or erosion surfaces, and contains a distinct pattern of marl-chalk couplets. These sequences correlate, within the constraints of biostratigraphy to European and New Jersey Margin sequence chronostratigraphy. Three …
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Updip Sequence Development on a Mixed Carbonate-Siliciclastic Continental Shelf, Paleogene, North Carolina, Eastern U.S.A.
… Albemarle Block to the north. The Paleogene supersequence set boundary is a hardground on Cretaceous shoreface/shallow-shelf mollusk facies. It is overlain by a thin Paleocene sequence of deeper offshore, glauconitic fine sands to deep marine silt-shale. Five regionally mappable, vertically …
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Depositional Environments and Sequence Stratigraphy of Upper Mississippian Strata in the Central Appalachian Basin
… interval. Seventeen transgressive-regressive sequences comprise the study interval in the basin depocenter. Five sequence types defined by the degree of incision and the thickness/ character of dominant facies include: 1) major incised valley-fill to coastal plain, 2) major incised valley-fill …
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Sequence Stratigraphic Architecture of Early Pennsylvanian, Coal-bearing Strata of the Cumberland Block: A Case Study from Dickenson County, Virginia
… origin. Architectural elements within 4th-order sequences consist of upward-fining lowstand and transgressive incised valley fill, alluvial, and estuarine deposits, and upward-coarsening highstand deltaic deposits that are separated by condensed sections. 4th-order sequences are stacked into …
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Sequence Stratigraphy and Petrophysics of the late Ordovician Utica-Point Pleasant Interval in the Middle Appalachian Basin, Eastern Ohio and Western Pennsylvania
… Late Mohawkian to Early Cincinnatian third-order sequences deposited in an active foreland basin during onset of the Taconic orogeny. Sequences consist of deepening upward successions of transgressive limestone and shale, recording a period of sustained subsidence and rising sea-level along the …
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Cyclostratigraphy of Late Cambrian cyclic carbonates: An interbasinal field and modelling study, U.S.A.
… cycles and the larger scale depositional sequences on which they are superimposed. Fining-upward peritidal cycles grade seaward into coarsening-upward, shallow to deep subtidal cycles that form a continuum across the carbonate platforms and are genetically linked to one another by shared …
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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
… was done to establish the high resolution sequence stratigraphy of a sediment-starved low-latitude epeiric sea platform during the transition from Ordovician icehouse to Devonian greenhouse. The Wabash Platform (approximately 200,000 square km area) is bounded to the north by the Michigan …
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