Download or read book Architecture and Seismic Geomorphology of Shelf Edge Deltas Along an Active Tectonic Margin Eastern Offshore Trinidad written by Julie Anne Maher and published by . This book was released on 2007 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tectonic Geomorphology of the Eastern Trinidad Shelf written by Tricia Grier Alvarez and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Few deltaic systems in tectonically active areas of the world exhibit more data for detailed study than the Orinoco Delta extending along the hydrocarbon-rich, narrow, eastern shelf of the island of Trinidad. The entire region has undergone tectonic extension, compression and transpression during the late Tertiary and into the Quaternary. Paralic and shelf reservoir sand distribution and geometry have been significantly influenced by both structuring and strong offshore current activity, as well as large forced and unforced sealevel regressions. These sedimentary deposits hold significant shallow gas resources across the region, but the complexity of their distribution and architecture is poorly understood. A large merged 3D seismic survey (~9,000 sq km) was integrated with well penetrations across the modern shelf to examine the influence of structuring on near-modern basin fill depositional morphology and architecture. Key reflecting horizons were mapped across the area and these document the structural opening of the basin by extension superimposed over ongoing uplift of compressional anticlines. Seismic attributes image reservoir elements such as channels and channel belts, tidally inundated interfluves and interdistributary areas which facilitate analysis of the scale and form of these features as well as enable evaluation of the influence of structure on deposition. Both larger channels (1-2 km wide) and smaller channels (less than 100 meters) show patterns of avulsion and lateral migration and appear to be ubiquitous in some areas of the shelf during lowstand times. The largest major sediment fairway (valley) is long-lived (~1.0 million years) and structurally confined by east-west trending anticlinal uplifts, funneling sediments down the axis of the basin. Alternations between surfaces with well defined depositional elements interpreted to be indicative of subaerial conditions, and surfaces devoid of such features which have been interpreted to be submarine in nature suggest large scale fluctuations in the depositional environment over time under the influence of changes in sea level. Extensional faults, which show a complex pattern of displacement, both spatially and temporally; appear to remain active up to near present day time. Coupled with the apparent long-lived nature of the tectonic uplifts in this region, observations suggest that the structure is controlling sedimentation, as opposed to sedimentation driving deformation. Structure is playing a significant role in accommodation creation and therefore the location of the axis of sediment transport and accumulation throughout the Pleistocene history of the basin. This conclusion would be in keeping with the regional structural history of the basin showing transpression between the east-southeastward moving Caribbean Plate and stationary South American plate, initiated in the early Tertiary and continuing to the present day. Quantitative data on systems tract architectural elements, including spatial orientation and distribution should significantly improve 3D modeling of these reservoirs and improve understanding of sand distribution and the processes of sediment transfer from proximal sources to shelf staging areas

Download or read book Stratigratigraphic Architecture and Basin Fill Evolution of a Plate Margin Basin Eastern Offshore Trinidad and Venezuela written by Emilio José Garciacaro and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eastward migration of the Caribbean plate relative to the South American plate is recorded by a 1100-km-long foreland basin which is oldest in the west (Maracaibo basin, 65-55 Ma) and youngest in the east (Columbus basin, eastern offshore Trinidad, 15-0 Ma). Regional transpression has caused lithospheric loading and flexure along the northern margin of South America creating a large foreland basin area which propagated from west to east as the Caribbean plate moved eastward relative to the South American plate. I have integrated 775 km of deep-penetration 2D seismic lines acquired by the 2004 BOLIVAR survey, 325 km of 1975 GULFREX seismic data, 8,000 km2 of industry 3-D seismic data, and published industry well data from offshore eastern Trinidad. Interpretation of seismic sections tied to wells reveals the following fault chronology: 1) middle Miocene thrusting along the Darien ridge related to highly oblique convergence between the Caribbean plate and the passive margin of northern South America; continuing thrusting and transpression in an oblique foreland basin setting through the early Pleistocene; 2) early Pliocene-recent low-angle normal faults along the top of the Cretaceous passive margin; these faults were triggered by oversteepening related to formation of the downdip, structurally and bathymetrically deeper, and more seaward Columbus basin; large transfer faults with dominantly strike-slip displacements connect gravity-driven normal faults that cluster near the modern shelf-slope break and trend in the downslope direction; to the south no normal faults are present because the top Cretaceous horizon has not been oversteepened as it is adjacent to the foreland basin; 3) early Pliocene-Recent strike-slip faults parallel to the trend of the Darien ridge and accommodate present-day plate motions. Active mud diapirism in the Columbus basin is widespread and is related to overthrusting and loading of upper Miocene-lower Pliocene age mud. Analysis of the 3-D seismic data reveals the presence of extensive gravity-flow depositional elements on the Columbus basin deepwater area, characterized by mass-transport deposits at the base, turbidite frontal-splay deposits, leveed-channel deposits, and capped by fine-grained condensed-section deposits. Deep basin wells drilled in recent years have proven that turbidites were transported into the Columbus basin deepwater during the Plio-Pleistocene. Analysis of these well results suggest that a deeper oil charge is present within the Columbus basin deepwater area. The primary uncertainty for this variable hydrocarbon system is whether fault or diapiric pathways connect the petroleum charge at depth with shallower reservoir rocks

Download or read book Seismic Geomorphology written by R. J. Davies and published by Geological Society of London. This book was released on 2007 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: We are poised to embark on a new era of discovery in the study of geomorphology. The discipline has a long and illustrious history, but in recent years an entirely new way of studying landscapes and seascapes has been developed. It involves the use of 3D seismic data. Just as CAT scans allow medical staff to view our anatomy in 3D, seismic data now allows Earth scientists to do what the early geomorphologists could only dream of - view tens and hundreds of square kilometres of the Earth's subsurface in 3D and therefore see for the first time how landscapes have evolved through time. This volume demonstrates how Earth scientists are starting to use this relatively new tool to study the dynamic evolution of a range of sedimentary environments.

Download or read book Subaqueous Mass Movements and Their Consequences written by A. Georgiopoulou and published by Geological Society of London. This book was released on 2020-07-08 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This GSL volume focuses on underwater or subaqueous landslides with the overarching goal of understanding how they affect society and the environment. The new research presented here is the result of significant advances made over recent years in directly monitoring submarine landslides, in standardising global datasets for quantitative analysis, constructing a global database, and leading international research projects. This volume demonstrates the breadth of investigation taking place into subaqueous landslides, and shows that while events like the recent ones in the Indonesian archipelago can be devastating they are at the smaller end of what the Earth has experienced in the past. Understanding the spectrum of subaqueous landslide processes, and therefore the potential societal impact, requires research across all spatial and temporal scales. This volume delivers a compilation of state-of-the-art papers covering topics from regional landslide databases to advanced techniques for in situ measurements, to numerical modelling of processes and hazards.

Download or read book Passive Margins written by K.R. McClay and published by Geological Society of London. This book was released on 2020-07-01 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume has evolved from papers written in memory of Professor David Roberts. They summarize the key findings of recent research on passive margins, from tectonics, bathymetry, stratigraphy and sedimentation, structural evolution and magmatism. Papers include analyses of the central and southern Atlantic margins of South America and Africa, papers on magmatism and extension in the NE Brazilian margin and on the Cote de Ivoire margin, rift architectures of the NW Red Sea margin, tectonics of the eastern Mediterranean margin, salt tectonics of passive margins of the Gulf of Mexico and Brazil, and papers on the NW Shelf margin of Australia. The volume provides readers with new insights into the complexities of passive margin systems that are in reality, not so passive.

Download or read book The Analysis of Diffuse Triple Junction Zones in Plate Tectonics and the Pirate Model of Western Caribbean Tectonics written by D. Fraser Keppie and published by Springer Science & Business Media. This book was released on 2014-02-17 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern researchers in plate tectonics may be concerned with the analysis of distributed deformation across diffuse plate boundaries and triple junction zones. This book extends classic methods of kinematic analysis first developed in the 1960s to the more general scenarios of diffuse deformation zones between plates. The analytic methods presented specifically target the non-rigid deformation implied by unstable triple junction configurations. These methods are then applied to the tectonic evolution of western Caribbean region which provides new ways to test and challenge the established Pacific model of Caribbean tectonics. Possible advantages of the new Pirate model of Caribbean tectonics are discussed in terms of paleo-geography and paleo-ocean connections, as well as mineral and hydrocarbon potential and seismic risks across the region.

Download or read book Shelf edge Deltas written by Joshua Francis Dixon and published by . This book was released on 2013 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research investigates the character and significance of shelf-edge deltas within the sedimentary source-to-sink system, and how variability at the shelf edge leads to different styles of deep-water deposition. Because the shelf-edge represents one of the key entry points for terrigenous sediment to be delivered into the deep water, understanding of the sedimentary processes in operation at these locations, and the character of sediment transported through these deltas is critical to understanding of deep-water sedimentary systems. The research was carried out using three datasets: an outcrop dataset of 6000 m of measured sections from the Permian-Triassic Karoo Basin, South Africa, a 3D seismic data volume from the Eocene Northern Santos Basin, offshore Brazil and a dataset of 29 previously published descriptions of shelf-edge deltas from a variety of locations and data types. The data presented highlight the importance of sediment instability in the progradation of basin margins, and deep-water transport of sediment. The strata of the Karoo Basin shelf margin represent river-dominated delta deposits that become more deformed as the shelf-edge position is approached. At the shelf edge, basinward dipping, offlapping packages of soft-sediment-deformed and undeformed strata record repetitive collapse and re-establishment of shelf-edge mouth bar packages. The offlapping strata of the Karoo outcrops record progradation of the shelf margin through accretion of the shelf-edge delta, for over 1 km before subsequent transgression. The Eocene Northern Santos Basin shelf margin, in contrast, exhibits instability features which remove kilometers-wide wedges of the outer shelf that are transported to the basin floor to be deposited as mass-transport packages. In this example, shelf-edge progradation is achieved through 'stable' accretion of mixed turbidites and contourites. The data also emphasize the importance of the role of shelf-edge delta processes in the delivery of sediment to the basin floor. A global dataset of 29 examples of shelf-edge systems strongly indicates that river domination of the shelf-edge system (as read from cores, well logs or isopach maps) serves as a more reliable predictor of deep-water sediment delivery and deposition than relative sea level fall as traditionally read in shelf-edge trajectories or sequence boundaries.

Download or read book Conjugate Divergent Margins written by Webster Mohriak and published by Geological Society of London. This book was released on 2013 with total page 569 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main focus of the book is the geological and geophysical interpretation of sedimentary basins along the South, Central and North Atlantic conjugate margins, but concepts derived from physical models, outcrop analogues and present-day margins are also discussed in some chapters. There is an encompassing description of several conjugate margins worldwide, based on recent geophysical and geological datasets. An overview of important aspects related to the geodynamic development and petroleum geology of Atlantic-type sedimentary basins is also included. Several chapters analyse genetic mechanisms and break-up processes associated with rift-phase structures and salt tectonics, providing a full description of conjugate margin basins based on deep seismic profiles and potential field methods.--

Download or read book Three dimensional Facies and Process regime Variability in Shelf edge Deltas written by Fabien J. Laugier and published by . This book was released on 2014 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Depositional Environments of Unstable Shelf margin Deltas of the Oligocene Vicksburg Formation McAllen Ranch Field South Texas written by Richard P. Langford and published by . This book was released on 1994 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sequence Stratigraphy and Composition of Late Quaternary Shelf Margin Deltas High Island Area Offshore Texas written by Robert A. Morton and published by . This book was released on 1993 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Shelf Width Variability Controls Sediment Dispersal on Active Margins written by Emily Wei and published by . This book was released on 2019 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-resolution CHIRP and multi-channel seismic data paired with sediment cores provide an unprecedented view of forcing functions on continental margin deposits. Serving as reservoirs for hydrocarbons, sand, and aquifers, continental margin deposits have societal and scientific relevance. Traditionally, relative sea-level and sediment supply are considered the dominant controls on the geometry of continental shelf deposits. On active margins studied in this dissertation, tectonic deformation plays a large role in controlling shelf geometry, as deformation is at high angles to the shoreline. Sediment storage and dispersal are modified further by energetic oceanographic currents and climate. In the Gulf of Papua (GoP), clinothem architecture and surfaces of lap are not dependent on eustatic sea level changes. As a result of foreland basin tectonics, subsidence in the northeast GoP engenders aggradational Holocene clinoforms whereas peripheral bulge uplift in the southwest GoP causes toplap. Along-margin currents build the clinothem obliquely to the northeast. Downcore clay mineralogy constrain contributions of the Fly and Purari rivers to the GoP clinothem and lowstand deep-water basin deposits. Results suggest that sediment source and routing changed through a sea level cycle. Fly River sediment may have bypassed the inner mid-shelf clinothem during intermediate lowstands due to narrower shelf widths that allow for the establishment of incised valleys. Depocenters of post-glacial shelf deposits offshore of the Oceano Dunes State Vehicular Reservation in Central California are influenced by eustatic sea-level changes in the cross-shore direction and uplift of the San Luis Block and subsidence of the Santa Maria Basin in the along-margin direction. The timing and emplacement of turbidite deposits from submarine canyon systems offshore of San Onofre (SO) and Dana Point (DP) may be controlled primarily by shelf width. Wide shelves offshore of SO were formed by transpression along the right-lateral Newport-Inglewood/Rose Canyon Fault Zone. Turbidites offshore of SO were deposited during and prior to the last sea-level lowstand, whereas turbidites were deposited offshore DP through the sea-level transgression and highstand. Second-order controls on local turbidite emplacement include small synclines and anticlines that engender deposition or promote sediment bypass.

Download or read book Active Strike slip and Collisional Tectonics of the Northern Caribbean Plate Boundary Zone written by James F. Dolan and published by Geological Society of America. This book was released on 1998-01-01 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Stratigraphy and Hydrocarbon Traps written by Allen Lowrie and published by . This book was released on 1994 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mass transport Deposits in Deepwater Settings written by R. Craig Shipp and published by SEPM Soc for Sed Geology. This book was released on 2011 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Historically, submarine-mass failures or mass-transport deposits have been a focus of increasingly intense investigation by academic institutions particularly during the last decade, though they received much less attention by geoscientists in the energy industry. With recent interest in expanding petroleum exploration and production into deeper water-depths globally and more widespread availability of high-quality data sets, mass-transport deposits are now recognized as a major component of most deep-water settings. This recognition has lead to the realization that many aspects of these deposits are still unknown or poorly understood. This volume contains twenty-three papers that address a number of topics critical to further understanding mass-transport deposits. These topics include general overviews of these deposits, depositional settings on the seafloor and in the near-subsurface interval, geohazard concerns, descriptive outcrops, integrated outcrop and seismic data/seismic forward modeling, petroleum reservoirs, and case studies on several associated topics. This volume will appeal to a broad cross section of geoscientists and geotechnical engineers, who are interested in this rapidly expanding field. The selection of papers in this volume reflects a growing trend towards a more diverse blend of disciplines and topics, covered in the study of mass-transport deposits.

Download or read book Controls on Sedimentary Processes and 3D Stratigraphic Architecture of a Mid Miocene to Recent Mixed Carbonate siliciclastic Continental Margin written by Carla Maria Sanchez and published by . This book was released on 2011 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Determining the relative importance of processes that control the generation and preservation of continental margin stratigraphy is fundamental to deciphering the history of geologic, climatic and oceanographic forcing imprinted on their sedimentary record. The Northern Carnarvon Basin (NCB) of the North West Shelf of Australia has been a site of passive margin sedimentation throughout the Neogene. Cool-water carbonate sedimentation dominated during the early-middle Miocene, quartz-rich siliciclastics prograded over the shelf during the late-middle Miocene, and carbonate sedimentation resumed in the Pliocene. Middle Miocene to Pliocene siliciclastics were deposited as clinoform sets interpreted as delta lobes primarily based on their plan-view morphology and their relief of 40-100 m. Shelf-edge trajectory analysis suggests that part of this stratigraphic succession was built during a long-term, third order, regressive phase, producing shelf-edge deltas, followed by an aggradational episode. These trends appear to correlate with third-order global eustatic cycles. Slope incisions were already conspicuous on the slope before deltas reached the shelf-break. Nevertheless, slope gullies immediately downdip from the shelf-edge deltas are wider and deeper (>1 km wide, ~100 m deep) than coeval incisions that are laterally displaced from the deltaic depocenter (~0.7 km wide, ~25 m deep). This change in gully morphology is likely the result of greater erosion by sediment gravity flows sourced from shelf-edge deltas. Total late-middle to late Miocene margin progradation increased almost three times from 13 km in the southwest to 34 km in the northeast, where shelf-edge deltas were concentrated. Flat-topped carbonate platforms seem to have initiated on subtle antecedent topographic highs resulting from these deltaic lobes. A reduction of siliciclastic supply to the outer paleo-shelf during the Pliocene combined with the onset of a southwestward-flowing, warm-water Leeuwin Current (LC) most likely controlled the initiation of these carbonate platforms. These platforms display marked asymmetry, likely caused by an ancestral LC, which created higher-angle, upcurrent platform margins, and lower-angle, downcurrent clinoforms. The along-strike long-term migration trend of the platforms could be the result of differential subsidence. These platforms constitute the first widespread accumulation of photozoan carbonates in the Northern Carnarvon Basin. They became extinct after the mid-Pleistocene when the LC weakened or became more seasonal.