Intraplate Deformation of Oceanic Crust in the West Somali Basin: Insights From Long-offset Reflection Seismic Data

Sinemurian phosphorites in southeastern British Columbia and southwestern Alberta conform with the "West Coast type" phosphorite depositional model. The model indicates that they were deposited on or near the Early Jurassic western cratonic margin, next to a sea or trough from which cold water upwelled. This suggests that the allochthonous terrane Quesnellia lay well offshore in Sinemurian time. The sea separating Quesnellia from North America was partly floored by oceanic crust ("Eastern Terrane") and partly by a thick sequence of rifted, continental terrace wedge rocks comprising the Purcell Supergroup and overlying Paleozoic sequence. This sequence must have been depressed sufficiently that access of upwelling deep currents to the phosphorite depositional area was not impeded.

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Vertical exaggeration of reflection seismic data in geoscience publications 2006–2010

Marine and Petroleum Geology ◽

10.1016/j.marpetgeo.2010.10.003 ◽

2011 ◽

Vol 28 (5) ◽

pp. 959-965 ◽

Cited By ~ 6

Author(s):

S.A. Stewart

Keyword(s):

Seismic Data ◽

Reflection Seismic

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Using reflection seismic method to estimate the fluid dynamics parameters related to wakes

10.5194/egusphere-egu21-9332 ◽

2021 ◽

Author(s):

Wenhao Fan ◽

Haibin Song ◽

Kun Zhang ◽

Yi Gong ◽

Shun Yang ◽

...

Keyword(s):

Potential Vorticity ◽

Negative Potential ◽

Distribution Area ◽

The West ◽

West Side ◽

Reflection Seismic ◽

Vorticity Distribution ◽

Positive Vorticity ◽

Coherent Vortices ◽

Survey Line

<p>In this study, when using reflection seismic data to study the wakes of the Batan Islands, a method for estimating the fluid dynamics parameters such as the relative vorticity (relative Rossby number) and the relative potential vorticity is proposed. Although the relative Rossby number estimation method proposed in this study cannot guarantee absolute accuracy in the calculation value, this method is more accurate in describing the positive and negative vorticity distribution for the wakes, and the resolution of the positive and negative vorticity distribution described by this method is higher than the result of the reanalysis data. For the wakes developed in the Batan Islands, the reflection events in the wake development area have the larger inclination than the reflection events in the western Pacific water distribution area. It is also found that the negative vorticity wakes are mainly distributed on the west side of the island/ridge, and the positive vorticity wakes are mainly distributed on the east side of the island/ridge. This is consistent with the understanding of previous wakes simulations. The strong vorticity values in the study area are mainly distributed at depths above 300m, and the maximum impact depth of wakes can reach 600m. At the downstream position of the wake on the survey line 7, it can be seen that the bottom boundary layer has separated, and there is the negative vorticity wakes on the west side intruding into the positive vorticity wakes on the east side , which is presumed to be caused by the disturbance of the small anticyclone existing near the Batan Islands. For the survey line 7, the negative potential vorticity is mainly distributed on the west side of the island/ridge, and the influence range can reach the sea depth of 600m. In the negative potential vorticity region, there is strong energy dissipation and vertical shear. In this study, we don&#8217;t find the existence of submesoscale coherent vortices on the survey line 7, but find the reflection structure similar to filaments on the seismic section. Combined with the analysis of the balanced Richardson number angle of survey line 7, we speculate that the wake in the negative potential vorticity distribution area has the characteristics of symmetrical instability, and the symmetrical instability may destroy the process of filaments forming submesoscale coherent vortices.</p>

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Efficient progressive transfer learning for full waveform inversion with extrapolated low-frequency reflection seismic data

IEEE Transactions on Geoscience and Remote Sensing ◽

10.1109/tgrs.2021.3129810 ◽

2021 ◽

pp. 1-1

Author(s):

Yuchen Jin ◽

Wenyi Hu ◽

Shirui Wang ◽

Yuan Zi ◽

Xuqing Wu ◽

...

Keyword(s):

Transfer Learning ◽

Seismic Data ◽

Waveform Inversion ◽

Low Frequency ◽

Full Waveform Inversion ◽

Reflection Seismic ◽

Full Waveform

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Assessing the repeatability of reflection seismic data in the presence of complex near-surface conditions CO2CRC Otway Project, Victoria, Australia

ASEG Extended Abstracts ◽

10.1071/aseg2009ab016 ◽

2009 ◽

Vol 2009 (1) ◽

pp. 1

Author(s):

Y. Al Jabri ◽

M. Urposevic ◽

A. Kepic ◽

B. Evans

Keyword(s):

Seismic Data ◽

Near Surface ◽

Surface Conditions ◽

Reflection Seismic

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Application of seismo-stratigraphic interpretation techniques to offshore West Greenland

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v140.8037 ◽

1988 ◽

Vol 140 ◽

pp. 64-66

Author(s):

J.A Chalmers

Keyword(s):

Pilot Study ◽

Seismic Data ◽

Seismic Interpretation ◽

Shelf Break ◽

The West ◽

Regional Geology ◽

West Greenland ◽

Oil Companies ◽

Greenland Basin ◽

Basement Ridge

A pilot study is being conducted to determine if the use of seismo-stratigraphic interpretation techniques can increase the understanding af the geology of offshore West Greenland in order to reassess the prospectivity of the area. During the period 1975 to 1979, a number of concessions offshore West Greenland were licensed to various consortia of oil companies to search for petroleum. Some 40 000 km of seismic data were acquired, all of which is now released. Five wells were drilled, all of them dry, and all concessions were relinquished by the industry by 1979. The regional geology of offshore West Greenland has been summarised by Manderscheid (1980) and Henderson et al. (1981). They show the West Greenland Basin to consist of fairly uniformly westward dipping sediments bordered near the shelf break by a basement ridge. These authors used what may be termed 'conventional' techniques of seismic interpretation. However, since that time the techniques of seismo-stratigraphy (Vail et al., 1977; Hubbard et al., 1985) have become established. They are now being applied to study seismic data acquired during the mid-1970s.

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Late Paleocene radiolarian fauna from Tibet and its geological implications

Canadian Journal of Earth Sciences ◽

10.1139/e2012-054 ◽

2012 ◽

Vol 49 (11) ◽

pp. 1364-1371 ◽

Cited By ~ 10

Author(s):

Yinping Liang ◽

Kexin Zhang ◽

Yadong Xu ◽

Weihong He ◽

Xianyin An ◽

...

Keyword(s):

Oceanic Crust ◽

Foreland Basin ◽

The West ◽

Southern Tibet ◽

Terminal Stage ◽

Oceanic Basin ◽

Late Paleocene ◽

Geological Implications ◽

Yarlung Zangbo Suture Zone ◽

Radiolarian Fauna

A diverse, abundant, and well-preserved radiolarian fauna in Jiazhu, Zhongba County of Tibet, in the western sector of Yarlung Zangbo Suture Zone, is assigned to a late Paleocene radiolarian zone, the Buryella pentadica interval zone, spanning 59–56.5 Ma. Regionally, a late Paleocene basalt block in the bathyal–abyssal siliceous mudstone and graywacke yielded an age of 59.1 Ma (zircon SHRIMP U–Pb). The late Paleocene radiolarian fauna, the tectonic attribution of the radiolarian cherts and the basalt block indicate that oceanic crust persisted in the Zhongba area until the late Paleocene and the initial collision between the Indian and Eurasian plates post-dates the late Paleocene. It is inferred that the Neo-Tethys transformed into a remnant oceanic basin in the late Paleocene, at the terminal stage of the oceanic crust subduction, and the closure of the remnant oceanic basin in the studied region took place after the late Paleocene. In contrast to the previous investigations, we suggest that there was a remnant oceanic basin to the west of the Saga area and a foreland basin to the east of Saga in southern Tibet during the late Paleocene. We argue that the closure of the Neo-Tethys progressed from east to west.

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