scholarly journals SEISMIC STRATIGRAPHY OF THE EOCENE–LOWER OLIGOCENE IN THE URUGUAYAN CONTINENTAL MARGIN / ESTRATIGRAFIA SÍSMICA DO EOCENO AO OLIGOCENO INFERIOR NA MARGEM CONTINENTAL URUGUAIA

2018 ◽  
Vol 3 (4) ◽  
pp. 290-306 ◽  
Author(s):  
Belén Viera Honegger ◽  
Ethel Morales ◽  
Matias Soto ◽  
Bruno Conti
Keyword(s):  
Continental Margin ◽  
Sedimentary Basins ◽  
Seismic Facies ◽  
Depositional Sequences ◽  
Normal Regression ◽  
Depositional Systems ◽  
Seismic Sections ◽  
Pelotas Basin ◽  
Definition Of ◽  
Stacking Patterns

The Uruguayan continental margin was generated following the fragmentation of the Gondwana supercontinent and the subsequent opening of South Atlantic Ocean. It constitutes an extensive sedimentation area in which three sedimentary basins can be found: the Punta del Este Basin, the southernmost portion of the Pelotas Basin, and the poorly defined Oriental del Plata Basin. The aim of this work was the identification and characterization of the different seismic units (seismic facies, systems tracts, depositional sequences) for the sedimentary interval assigned to the Eocene in the Uruguayan continental margin. Sequence stratigraphy was used as a basin analysis method for this purpose, using a database that consisted of approximately 10,000 kilometers of 2D seismic sections, acquired in exploratory surveys in 2007 and 2008. The workflow included the recognition of stacking patterns and/or stratal terminations, the definition of genetically significant stratigraphic surfaces and, based on these, the identification of systems tracts and depositional sequences. Three depositional sequences were identified in the studied sedimentary interval. The basal sequence is composed of four depositional systems tracts, including falling stage, normal regression (lowstand and highstand) and transgressive deposits. The intermediate sequence only preserves lowstand normal regression deposits. The third sequence is composed by three depositional systems tracts, including lowstand, transgressive and falling stage deposits. ResumoA margem continental uruguaia foi gerada após a fragmentação do supercontinente Gondwana e a subsequente abertura do Oceano Atlântico Sul. Constitui uma extensa área de sedimentação em três bacias sedimentares: a bacia de Punta del Este, a porção mais ao sul da Bacia de Pelotas e a Bacia Oriental del Plata, pouco definida. O objetivo deste trabalho foi a identificação e caracterização das diferentes unidades sísmicas (fácies sísmicas, tratos de sistemas, seqüências deposicionais) para o intervalo sedimentar atribuído ao Eoceno na margem continental uruguaia. Com este objetivo, utilizou-se a estratigrafia de seqüencias como método de análise de bacias, tendo-se utilizado um banco de dados constituído por aproximadamente 10.000 km de seções sísmicas 2D, adquiridas em pesquisas exploratórias em 2007 e 2008. O trabalho incluiu o reconhecimento de padrões de empilhamento e/ou terminações estratais, a definição de superfícies estratigráficas geneticamente significativas, tendo-se efetuado com base nelas, a identificação de tratos de sistemas e seqüências deposicionais. Três seqüências deposicionais foram identificadas no intervalo sedimentar estudado. A seqüência basal é composta por quatro tratos de sistemas deposicionais, incluindo a fase de abaixamento do nível do mar, a regressão normal e depósitos transgressivos. A sequência intermediária apenas preserva os depósitos de regressão normais de nível de mar baixo. A terceira seqüência é composta por três tratos de sistemas deposicionais, incluindo depósitos de nível de mar baixo, transgressivos e de abaixamento do nível do mar.

scholarly journals Application of seismic stratigraphy in reservoir characterisation: a case study of the passive margin deposits of the northern Orange Basin, South Africa

2020 ◽  
Author(s):  
Chris Adesola Samakinde ◽  
Jan Marinus Van Bever Donker ◽  
Ray Durrheim ◽  
Musa Manzi
Keyword(s):  
South Africa ◽  
Mass Transport ◽  
Gamma Ray ◽  
Sedimentary Basins ◽  
Seismic Stratigraphy ◽  
Passive Margin ◽  
Seismic Facies ◽  
Depositional Sequences ◽  
Seismic Reflectors ◽  
Mass Transport Deposits

AbstractThe Barremian-Cenozoic depositional sequences in the northern Orange Basin, SW, South Africa, were investigated using the principles of seismic stratigraphy to understand the interplay of tectonics and sedimentary processes in the distribution of potential hydrocarbon reservoirs. A seismic stratigraphic workflow (seismic sequence, seismic facies and lithofacies analysis) was completed by utilising three seismic lines (L1, L2 and L3) tied to Wireline data (gamma, checkshots and sonic) in two exploration wells (A1 and A2). Seven depositional sequences were mapped followed by the creation of lithofacies log interpreted from the gamma-ray log (GR) by setting maximum GR value at 60 API for Sandstone, 60–100 API for Siltstone and above 100 API for Shale. Six seismic facies units are recognised based on internal geometry and configurations of the seismic reflectors; Tangential-Oblique (SF1), Hummocky (SF2), Wavy-Parallel (SF3), Chaotic (SF4), Sub-parallel/parallel (SF5) and Divergent (SF6). SF4 is dominant within the Barremian-Aptian sequence and expressed in an incised valley fill, suggesting mass transport deposition accompanied by strong hydrodynamic conditions. Evidence of sedimentary basins progradation is seen within the Late-Albian-Turonian sequences, because of the occurrences of SF2, SF6 and SF 4 facies. SF5 facies is prominent in the Maastrichtian/Campanian sequence, indicating that the deposition of sediments may have been accompanied by uniform margin subsidence after the Late-Cretaceous uplift of the Africa margin. The occurrence of SF1 and SF4 facies within the Cenozoic sequence indicates terrigenous pro-deltaic deposits and mass transport deposits, respectively. Further results from seismic-lithofacies modelling reveal that sand deposits of Barremian-Aptian (SF4 facies unit) and Albian sequences (SF2 and SF6 facies units) are potential stratigraphic reservoirs in this part of the basin.

scholarly journals Speculative petroleum systems of the Punta del Este Basin (offshore Uruguay)

2017 ◽  
Vol 47 (4) ◽  
pp. 645-656 ◽  
Author(s):  
Ethel Morales ◽  
Hung Kiang Chang ◽  
Matías Soto ◽  
Gerardo Veroslavsky ◽  
Bruno Conti ◽  
...  
Keyword(s):  
Continental Margin ◽  
Late Cretaceous ◽  
Petroleum System ◽  
The Other ◽  
Basin Evolution ◽  
Petroleum Systems ◽  
Sedimentary Evolution ◽  
Seismic Sections ◽  
Well Data ◽  
Pelotas Basin

ABSTRACT: The Uruguayan continental margin was generated as the result of the breakup of Gondwana and, later, the opening of the South Atlantic Ocean, which began in the Jurassic. Three major areas of Meso-Cenozoic sedimentation are located in the Uruguayan offshore: the Punta del Este Basin, the southernmost sector of the Pelotas Basin and the Oriental del Plata Basin. These basins share the classical stages of tectono-sedimentary evolution of the other Atlantic basins, including the prerift (Paleozoic), rift (Jurassic-Early Cretaceous), transition (Barremian-Aptian) and postrift (Aptian-present) phases. Based on the analysis of basin evolution through seismic sections and well data as well as on the establishment of analogies with productive Atlantic basins, four speculative petroleum systems are proposed for the Punta del Este Basin: 1) Marine petroleum system of the prerift stage: Devonian/Permian-Devonian/Permian(?), 2) Lacustrine petroleum system of the synrift stage: Neocomian-Neocomian(?), 3) Marine petroleum system of the Cretaceous postrift: Aptian-Late Cretaceous(?), 4) Marine petroleum system of the Cenozoic postrift: Paleocene-Paleogene/Neogene(?).

scholarly journals The interpretation of seismic facies in the molassic deposition of Preadriatic Foredeep

2001 ◽  
Vol 34 (4) ◽  
pp. 1493
Author(s):  
A. GJIKA ◽  
S. GURI ◽  
M. GURl ◽  
M. GJIKA ◽  
E. TRIFONI
Keyword(s):  
Sedimentary Facies ◽  
Seismic Facies ◽  
Environmental Interpretation ◽  
Facies Associations ◽  
Vertical Evolution ◽  
Depositional Systems ◽  
Definition Of ◽  
Active Processes ◽  
Lateral Variations ◽  
Depositional Elements

The purpose of this article is to illustrate the principles of seismic facie analysis used in the interpretation of sedimentary rocks, in siliciclastic deposits, especially in molassic one. The recognition and definition of a seismic facies and the analysis of its vertical evolution (facies associations) lead to an environmental interpretation, which can give useful information on both sedimentary facies and reservoir characteristics. With this aim, the major depositional systems, from continental to deep marine, and the depositional elements in which they can be subdivided, will be briefly overviewed in terms of extension, geometry, continuity and lateral variations. For each of these systems, it is pointed out, the major physical active processes during the deposition, the resulting sedimentary structures and their vertical and lateral evolution. The comparison between the environmental interpretation derived from bottom cores, well - logs and that derived from the current depositional models, is used to predict the nature and distribution of reservoir and sealing rocks.

Paleozoic formations of the Northeast margin of the European platform

2006 ◽  
Author(s):  
A. I. Eliseev ◽  
◽  
A. I. Antoshkina ◽  
V. A. Saldin ◽  
N. Yu. Nikulova ◽  
...  
Keyword(s):  
Continental Margin ◽  
Sedimentary Basins ◽  
Passive Continental Margin ◽  
European Continent ◽  
History Of ◽  
Geodynamic Reconstructions

Paleozoic sedimentary basins of the northeast European Platform is a component of large megabasin of the northeast passive continental margin of the European continent in the Paleozoic. The establishment of a connection between a paleodynamic history of a basin and its sedimentary formations types, which are the most reliable indicators of geodynamic conditions, is one of the primary problems of modern lithology. Reliable indicators at geodynamic reconstructions are genetically predetermined by laterial and vertical lines of the sedimentary formations. Formations and lithological complexes being the brightest indicators of the paleodynamic regimes change of the basin have been considered formations lines of the passive continental margin of the westuralian type during the Paleozoic.

SEISMIC FACIES OF SHELFEDGE DEPOSITS, U.S. PACIFIC CONTINENTAL MARGIN

1983 ◽  
pp. 299-313 ◽  
Author(s):  
MICHAEL E. FIELD ◽  
PAUL R. CARLSON ◽  
ROBERT K. HALL
Keyword(s):  
Continental Margin ◽  
Seismic Facies

scholarly journals Effects of Cenozoic subduction along the outboard margin of the Northern Cordillera: Derived from e-book on the Northern Cordillera (Alaska and Western Canada) and adjacent marine areas

Geosphere ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 33-61
Author(s):  
Warren J. Nokleberg ◽  
David W. Scholl ◽  
Thomas K. Bundtzen ◽  
David B. Stone
Keyword(s):  
Continental Margin ◽  
Subduction Zones ◽  
Hot Springs ◽  
Sedimentary Basins ◽  
Oceanic Lithosphere ◽  
Popular Science ◽  
Strike Slip ◽  
Western Canada ◽  
Regional Effects ◽  
Marine Areas

Abstract This article describes the regional effects of Cenozoic subduction along the outboard margin of the Northern Cordillera (Alaska, USA, and Western Canada), and thereby acquaints the reader with several chapters of the e-book Dynamic Geology of the Northern Cordillera (Alaska, Western Canada, and Adjacent Marine Areas). This article and the e-book are written for earth-science students and teachers. The level of writing for the article and the source e-book is that of popular science magazines, and readers are encouraged to share this article with students and laypersons. The main thrust of the article is to present and describe a suite of ten regional topographic, bathymetric, and geologic maps, and two figures portraying deep-crustal sections that illustrate the regional effects of Cenozoic subduction along the outboard margin of the North American Cordillera. The regional maps and cross sections are described in a way that a teacher might describe a map to students. Cenozoic subduction along the margin of the Northern Cordillera resulted in the formation of the following: (1) underthrusting of terranes and oceanic lithosphere beneath Southern Alaska; (2) landscapes, including narrow continental shelves along Southern and Southeastern Alaska and Western Canada (the Canadian Cordillera) and continental-margin mountain ranges, including the Alaska Peninsula, Chugach Range, Saint Elias Mountains, and Cascade Mountains; (3) sedimentary basins; (4) an array of active continental strike-slip and thrust faults (inboard of subduction zones); (5) earthquake belts related to subduction of terranes and oceanic plates; (6) active volcanoes, including continental-margin arcs (the Aleutian, Wrangell, and Cascade Arcs) linked to subduction zones, and interior volcanic belts related to strike-slip faulting or to hot spots; (7) lode and placer mineral deposits related to continental margin arcs or subduction of oceanic ridges; (8) hot springs related to continental-margin arcs; (9) plate movements as recorded from GPS measurements; and (10) underthrusting of terranes and oceanic lithosphere beneath the Northern Cordillera.

Gravity and Deep Structure of the Continental Margin of Banks Island and Mackenzie Delta

1975 ◽  
Vol 12 (3) ◽  
pp. 378-394 ◽  
Author(s):  
L. W. Sobczak
Keyword(s):  
Continental Margin ◽  
Coastal Plain ◽  
Deep Structure ◽  
Gravity Anomalies ◽  
Sedimentary Basins ◽  
Drill Hole ◽  
The Arctic ◽  
Mackenzie Delta ◽  
Arctic Coastal Plain ◽  
Free Air Gravity

Regional and deep structure supported by drill hole, gravity, and seismic evidence is interpreted along five profiles—one across the Mackenzie Delta and four across the continental margin. Isostatic compensation has reduced the gravity effect of most structures but gravity anomalies are still sufficient to outline two major sedimentary basins—one very extensive and thick (>10 km) underlying the continental margin and Mackenzie Delta and the other narrow and shallow east and southeast of the Arctic Coastal Plain. A basement ridge separating these basins along the eastern side of the Arctic Coastal Plain is outlined by a trend of relative gravity highs.An arcuate belt of prominent elliptically-shaped free air gravity highs (peak values >100 mgal) over the continental break outlines an uncompensated region of mass excesses. These mass excesses are explained by pro-grading wedges (>2 km thick) of Quaternary and possibly Tertiary sediments that have displaced seawater and act as a load on the crust rather than by the alternative concepts of an uncompensated ridge or high density material in the basement.

Rift systems of the East Siberian basin, Arctic region

2020 ◽  
Author(s):  
Nickolay Zhukov ◽  
Anatoly Nikishin ◽  
Eugene Petrov
Keyword(s):  
Continental Margin ◽  
Large Scale ◽  
Block Structure ◽  
Sedimentary Basins ◽  
Rift System ◽  
Northwestern Part ◽  
Gravitational Fields ◽  
Stage Of Development ◽  
East Siberian Sea ◽  
Seismic Lines

<p>The growing interest of geoscientists to the Eastern Arctic shelf is caused one of the most important problems of the present time – the creation of a tectonic model for assessing the hydrocarbon potential of the Eastern Arctic basins. In this time, over the past decade, the study of the East Siberian sea seismic lines have increased. Now, we operated a new seismic data, the interpretation of which gives the key to understanding the structure of the East Siberian continental margin.</p><p>This paper presents an analysis of the tectonic structure and geological history of the shelf of the East Siberian continental margin based on the interpretation of seismic lines in conjunction with geological information.</p><p>The modern ideas of the East Arctic rift tectonic evolution and formation of sedimentary basins over the entire East Siberian shelf resulted from the large-scale tectonic and magmatism events took place and the intense rifting or stretching phase widespread the entire shelf in the Albian-Aptian.</p><p>The East Siberian basin includes the main structural elements, formed in a postcollisional destructive stage of development – the New Siberian rift, the De Long uplift, the Zhokhov Foredeep basin, the Melville trough, the Baranov rise, the Pegtymel trough, the Shelagskoe rise.</p><p><strong>The New Siberian rift</strong> is located between the elevations of the New Siberian Islands and the archipelago De Long. Rift extends in a southeast direction from the East-Anisin Trough deflection to the Islands of Faddeev Island and New Siberia Islands. The New Siberian rift is a bright negative structural element and clearly stands out on the maps of the anomalous magnetic and gravitational fields, contrasting with the positive anomalies of surrounding rises and ridges.</p><p><strong>De Long Plateau</strong> is a large positive structure. The uplift boundaries and internal structure are clearly visible in the gravitational and magnetic fields. The magnetic anomaly expressed in the De long, it is a typical for the areas of development of volcanogenic formations and basalts trap magmatism.</p><p><strong>The East Siberian Rift System</strong> located from the northwestern part of the De long Plateau to the eastern part of the North Chukchi basin. System includes the <strong>Melville trough</strong> in the southern part of the East Siberian Sea. The reflector packages on seismic lines in the De Long Plateau and The East Siberian Rift System indicate that continental rifting occurred over the mantle plum.</p><p>The length of the Melville trough is a 350-370 km; with a width of 100-150 km. Trough is the symmetrical deflection consists of two narrow rifts separated by a rise.</p><p>The eastern branch of the rift system of the Melville trough joins the <strong>Baranov rise</strong>. The Baranov rise has a block structure with the geometry of which is similar to the block structure of the De-Long Plateau.</p><p><strong>The Dremkhed</strong> <strong>trough</strong> is a deep rift structure transitional between the East Siberian and North Chukchi basins, the thickness of the sedimentary cover in central part of section is 7000 ms.</p><p>The study was funded by RFBR project - 18-05-70011.</p>

Sign in / Sign up

Export Citation Format

Share Document