scholarly journals New Understanding of the Petroleum Systems of Continental Margins of the World: 32nd Annual

2012 ◽  
Keyword(s):  
Continental Margins ◽  
Petroleum Systems ◽  
The World

The origin of elevated plateaus along passive continental margins

2020 ◽  
Author(s):  
Johan M. Bonow ◽  
Peter Japsen ◽  
Paul F. Green ◽  
James A. Chalmers
Keyword(s):  
Sea Level ◽  
Continental Margins ◽  
East Greenland ◽  
Passive Margins ◽  
Base Level ◽  
Wide Range ◽  
The World ◽  
Incised Valleys ◽  
Break Up ◽  
High Level

<p>Many passive continental margins around the world are characterised by elevated plateaus at 1 to 2 km or more above sea level cut by deeply incised valleys and commonly separated from an adjacent coastal plain by one or more escarpments. Mesozoic–Cenozoic rift systems parallel to the coast are commonly present offshore with a transition from continental to oceanic crust further offshore. These landscapes occur in arctic, temperate and tropical climate and in different geological settings independent of the time span since break-up (e.g. along the Atlantic from south to north).</p><p>The plateaux are typically more than 100 km wide, much larger in some cases, and extend hundreds of kilometres along the margin, cutting across bedrock of different ages and resistances. The key to understanding the formation of regional, low-relief erosion surfaces is the base-level, as this is the level to which fluvial systems grade the landscape. The most likely base level is sea level, particularly for locations along continental margins during the post-rift development of passive margins.</p><p>It is commonly assumed that the characteristic, large-scale morphology of elevated, passive continental margins with  high-level plateaux and deeply incised valleys persisted since rifting and crustal separation Further, it is assumed that the absence of post-rift sediments is evidence of non-deposition, despite continental-stretching theory predicting deposition of a thick post-rift sequence overlying both the rift and its margins.</p><p>However, our studies of the passive continental margins of West and East Greenland, Norway, NE Brazil and southern Africa provide evidence of km-scale, post-rift subsidence and that the plateau surfaces were graded to sea level long after break-up and subsequently lifted to their present elevations. In some of these cases, the presence of post-rift marine sediments at high elevation provide direct proof of this interpretation. Since elevated plateaux cut by deeply incised valleys are a characteristic feature of these and other margins, this similarity suggests that such topography elsewhere in the world may also be unrelated to the processes of rifting and continental separation. We present a wide range of evidence from passive margins around the world in support of this hypothesis,</p><p> </p><p>Bonow et al. 2014: High-level landscapes along the margin of East Greenland – a record of tectonic uplift and incision after breakup in the NE Atlantic. Global and Planetary Change.</p><p>Green et al. 2018: Post-breakup burial and exhumation of passive continental margins: Seven propositions to inform geodynamic models. Gondwana Research.</p><p>Japsen et al. 2019: Elevated passive continental margins: Numerical modeling vs observations. A comment on Braun (2018). Gondwana Research.</p>

scholarly journals Neotectonic mountain uplift and geomorphology

2019 ◽  
pp. 3-26
Author(s):  
C. D. Ollier ◽  
C. F. Pain
Keyword(s):  
Plate Tectonics ◽  
Volcanic Rocks ◽  
Passive Margin ◽  
Continental Margins ◽  
Lateral Compression ◽  
Mountain Building ◽  
Topographic Features ◽  
Active Margins ◽  
The World ◽  
Fold Belts

Mountains are topographic features caused by erosion after vertical uplift or mountain building. Mountain building is often confused with orogeny, which today means the formation of structures in fold belts. The common assumption that folding and mountain building go together is generally untrue. Many mountains occur in unfolded rocks, granites and volcanic rocks, so there is no direct association of folding and mountain building. In those places where mountains are underlain by folded rocks the folding pre-dates planation and uplift. The age of mountains is therefore not the age of the last folding (if any) but the age of vertical uplift. Since mountains are not restricted to folded rocks, lateral compression is not required to explain the uplift. A compilation of times of uplift of mountains around the world shows that a major phase of tectonic uplift started about 6 Ma, and much uplift occurred in the last 2 Ma. This period is known as the Neotectonic Period. It is a global phenomenon including mountains on passive continental margins, and those in deep continental interiors. Several hypotheses of mountain building have problems with this timing. Some fail by being only able to make mountains out of folded rock at continental margins. Many translate the vertical uplift into lateral compression, but vertical uplift alone can create mountains. The Neotectonic Period has important implications for geomorphology, climate and global tectonics. In geomorphology it does not fit into conventional theories of geomorphology such as Davisian or King cycles of erosion. Neotectonic uplift might initiate several cycles of erosion, but most planation surfaces are much older than the Neotectonic Period. The increasing relief associated with Neotectonic uplift affected rates of erosion and sedimentation, and also late Cenozoic climate. The Neotectonic Period does not fit within plate tectonics theory, in which mountains are explained as a result of compression at active margins: mountains in other locations are said to have been caused by the same process but further back in time. This is disproved by the young age of uplift of mountains in intercontinental and passive margin positions. Subduction is supposed to have been continuous for hundreds of millions of years, so fails to explain the world-wide uplifts in just a few million years. Geomorphologists should be guided by their own findings, and refrain from theory-driven hypotheses of plate collision or landscape evolution.

Geochemical Inversion Applied to Oil Samples from Lower Cretaceous Reservoirs, Southeast Abu Dhabi: Implications for Hydrocarbon Exploration

2021 ◽  
Author(s):  
Lozano Mario Jorge ◽  
Hilario Camacho ◽  
Jose Guevara
Keyword(s):  
Lower Cretaceous ◽  
Oil And Gas ◽  
Compositional Data ◽  
Structural Evolution ◽  
Hydrocarbon Exploration ◽  
Source Rocks ◽  
Abu Dhabi ◽  
Oil Composition ◽  
Petroleum Systems ◽  
The World

Abstract The Middle East contains some of the most fascinating and prolific oil provinces in the world. The combination of excellent source rocks of different geologic ages, the presence of outstanding reservoirs and ubiquitous seals, optimal thermal history, and structural evolution provides an ideal recipe to produce the largest oilfields in the world. The UAE is currently estimated to hold 6% of global oil reserves, 96% of which are within Abu Dhabi. However, exploration for additional recoverable reserves is becoming more challenging. Finding hydrocarbons for the future is dependent upon a detailed understanding of the petroleum systems and subtle play types. For southeastern Abu Dhabi, several petroleum systems have been proposed to explain the oil and gas accumulations in Lower Cretaceous reservoirs. This study presents the practical application of a geochemical inversion workflow to a set of oil samples from Lower Cretaceous reservoirs collected in two exploration wells recently drilled in southeastern Abu Dhabi. The geochemical inversion workflow is based on stable isotope, biomarker, and oil composition data. Preliminary results and comparisons with previously identified oil families in the UAE suggest that the oils were generated from a carbonate-rich source rock deposited during Jurassic time. Compositional data and detailed stratigraphic and structural analyses support the possibility of multiple episodes of lateral and vertical migrations. The implications and risk associated with the timing of oil generation and trap formation are presented here to define a path forward and guide the prospecting efforts within this exciting region.

MAPPING THE PLATE TECTONIC RECONSTRUCTION OF SOUTHERN AND SOUTHEASTERN AUSTRALIA AND IMPLICATIONS FOR PETROLEUM SYSTEMS

2001 ◽  
Vol 41 (1) ◽  
pp. 15 ◽  
Author(s):  
M.S. Norvick ◽  
M.A. Smith
Keyword(s):  
Second Phase ◽  
Continental Margins ◽  
Ocean Crust ◽  
Petroleum Systems ◽  
Southeastern Australia ◽  
Structural Style ◽  
Oceanic Spreading ◽  
Tasman Sea ◽  
Eastern Australia ◽  
Thermal Subsidence

Southern Australian breakup history is divisible into three phases. The first phase began with Callovian (c.159–165 Ma) rifting in the western Bight Basin. During the Tithonian (c.142–146 Ma), rifting extended eastwards into the Duntroon, Otway and Gippsland Basins. By the Valanginian (c.130–135 Ma), ocean crust formed between India and western Australia. Structural style in the western Bight changed to thermal subsidence. However, fluvio-lacustrine rift sedimentation continued in Duntroon, Otway and Gippsland until the Barremian (c.115–123 Ma) when these basins also changed to thermal subsidence. The diachronous progression of basin fill types produces a progressive shift in ages of potential source, seal and reservoir intervals along the margin.The second phase began during the Cenomanian (c.92–97.5 Ma) with uplift in eastern Australia, stress reorganisation and divergence of basin development. The Otway, Sorell and Great South Basins formed in a transtensional regime. These tectonics resulted in trap generation through faulting, inversion and wrenching. During the Santonian, oceanic spreading began in the southern Tasman Sea (c.85 Ma). Slow extension caused thinning of continental crust in the Bight and Otway Basins and subsidence into deeper water. Ocean crust formed south of the Bight Basin in the Early Campanian (c.83 Ma) and also started extending up the eastern Australian coast.The third stage in development was caused by Eocene changes to fast spreading in the Southern Ocean (c.44 Ma), final separation of Australia and Antarctica, and cessation of Tasman Sea spreading. These events caused collapse of continental margins and widespread marine transgression. The resultant loading, maturation and marine seal deposition are critical to petroleum prospectivity in the Gippsland Basin.

scholarly journals Huge Aquifer Imaged off the Atlantic Coast

Eos ◽  
2019 ◽  
Vol 100 ◽  
Author(s):  
Mary Morton
Keyword(s):  
Atlantic Coast ◽  
Continental Margins ◽  
The World

Offshore aquifers may be a common feature along passive continental margins around the world.

A pragmatist philosophy of psychological science and its implications for replication

2018 ◽  
Vol 41 ◽  
Author(s):  
Ana Gantman ◽  
Robin Gomila ◽  
Joel E. Martinez ◽  
J. Nathan Matias ◽  
Elizabeth Levy Paluck ◽  
...  
Keyword(s):  
William James ◽  
Mental Processes ◽  
Psychological Science ◽  
Behavioral Measurement ◽  
The World ◽  
Pragmatist Philosophy

AbstractA pragmatist philosophy of psychological science offers to the direct replication debate concrete recommendations and novel benefits that are not discussed in Zwaan et al. This philosophy guides our work as field experimentalists interested in behavioral measurement. Furthermore, all psychologists can relate to its ultimate aim set out by William James: to study mental processes that provide explanations for why people behave as they do in the world.

Culture and the plasticity of perception

2020 ◽  
Vol 43 ◽  
Author(s):  
Michael Lifshitz ◽  
T. M. Luhrmann
Keyword(s):  
Cultural Context ◽  
Sensory Experience ◽  
Cultural Learning ◽  
The World

Abstract Culture shapes our basic sensory experience of the world. This is particularly striking in the study of religion and psychosis, where we and others have shown that cultural context determines both the structure and content of hallucination-like events. The cultural shaping of hallucinations may provide a rich case-study for linking cultural learning with emerging prediction-based models of perception.

Let's call a memory a memory, but what kind?

2019 ◽  
Vol 42 ◽  
Author(s):  
Nazim Keven
Keyword(s):  
Episodic Memory ◽  
Animal Cognition ◽  
The World

Abstract Hoerl & McCormack argue that animals cannot represent past situations and subsume animals’ memory-like representations within a model of the world. I suggest calling these memory-like representations as what they are without beating around the bush. I refer to them as event memories and explain how they are different from episodic memory and how they can guide action in animal cognition.

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