3D seismic imaging of the submarine slide blocks on the North Slope, Alaska

Submarine landslides are mass movements that transport sediment across the continental shelf to the deep ocean. This phenomenon happens when the shear stress exceeds the frictional resistance of the slope. We analyze a variety of seismic attributes to interpret large submarine slide blocks on the North Slope, Alaska. Results show that the slide blocks appear as mounds with scarps associated with them on the seismic section. The slide blocks vary in size, depending on their distance away from the shelf. The pattern of the slide blocks affects the overlying sedimentation. Geological feature: Submarine slide blocks Seismic appearance: Mound-like steep ramp and scarp characteristics on seismic sections; blocky and irregular features with sharp boundaries on the horizon slices and seismic attributes Features with similar appearance: Mass-transport deposits; Remnant blocks; Reef deposits; Submarine channels; Gullies Formation: Torok Formation Age: Cretaceous Location: North Slope, Alaska Seismic data: Obtained from the Alaska Department of Natural Resources, Division of Oil and Gas, through the tax-credit program ( State of Alaska, 2017 , http://dggs.alaska.gov/gmc/seismic-well-data.php ) Analysis tools: Seismic attributes (such as coherent energy, Sobel-filter similarity, dip magnitude, and dip azimuth) and geobody extraction

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Application of seismic attributes and machine learning for imaging submarine slide blocks on the North Slope, Alaska

10.1190/segam2020-3426887.1 ◽

2020 ◽

Author(s):

Shuvajit Bhattacharya ◽

Miao Tian ◽

Jon Rotzien ◽

Sumit Verma

Keyword(s):

Machine Learning ◽

Seismic Attributes ◽

North Slope ◽

Submarine Slide ◽

The North

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Seismic attribute and petrophysics-assisted interpretation of the Nanushuk and Torok Formations on the North Slope, Alaska

Interpretation ◽

10.1190/int-2019-0112.1 ◽

2020 ◽

Vol 8 (2) ◽

pp. SJ17-SJ34 ◽

Cited By ~ 1

Author(s):

Shuvajit Bhattacharya ◽

Sumit Verma

Keyword(s):

Oil And Gas ◽

Gamma Ray ◽

Regional Scale ◽

Rock Physics ◽

Seismic Attributes ◽

North Slope ◽

Reservoir Properties ◽

Seismic Attribute ◽

Seismic Reflection Data ◽

The North

Exploration of the Brookian sandstone reservoirs in the Nanushuk and Torok Formations on the North Slope of Alaska is a hot topic and presents opportunities to the oil and gas community because of their shallow depth, vast extent, and scope of development. The consecutive hydrocarbon discoveries announced by Repsol-Armstrong, Caelus Energy, and ConocoPhillips in 2015, 2016, and 2017 have indicated the presence of the vast recoverable resources on the North Slope in the Nanushuk and Torok reservoirs. We have investigated the detailed geophysical and petrophysical characteristics of these reservoirs. Our goal is to detect dominant geologic features in these formations using a combination of seismic attributes at the regional scale and analyze critical petrophysical and rock physics properties to evaluate formation heterogeneities and identify the reservoir targets by integrating well log and core data at the well scale. The Nanushuk Formation is expressed as topset reflections, whereas the Torok and gamma-ray zone formations are expressed as foresets and bottomsets on the seismic reflection data. Using seismic attributes, we mapped the extent of different geomorphological features, including shelf edges, channels, slides, and basin-floor fans, all with significant amplitude anomalies. The shelf edges continue for tens to hundreds of miles along the north/northwest and east–west directions, depending on the areas. The internal characters of these formations delineated by conventional well logs and advanced petrophysical analysis reveal their vertical heterogeneities and complexities, in terms of reservoir properties. We conclude that the reservoirs are vertically and laterally heterogeneous. These are thin-bedded low-resistivity reservoirs. Only a few zones in the parasequences are oil-saturated. We find that a combination of low [Formula: see text] ratio and acoustic impedance can be a useful proxy to detect the hydrocarbon-bearing sand intervals in these formations.

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Knowledge Co-production in Contested Spaces: An Evaluation of the North Slope Borough – Shell Baseline Studies Program

ARCTIC ◽

10.14430/arctic67804 ◽

2019 ◽

Vol 72 (1) ◽

pp. 43-57 ◽

Cited By ~ 3

Author(s):

Nathan P. Kettle

Keyword(s):

Oil And Gas ◽

Steering Committee ◽

Lessons Learned ◽

The Arctic ◽

North Slope ◽

Oil And Gas Development ◽

Boundary Organization ◽

Contested Spaces ◽

The North ◽

Trade Offs

Supporting the development of trusted and usable science remains a key challenge in contested spaces. This paper evaluates a collaborative research agreement between the North Slope Borough of Alaska and Shell Exploration and Production Company—an agreement that was designed to improve collection of information and management of issues associated with the potential impacts of oil and gas development in the Arctic. The evaluation is based on six categories of knowledge co-production indicators: external factors, inputs, processes, outputs, outcomes, and impacts. Two sources of data were used to assess the indicators: interviews with steering committee members and external science managers (n = 16) and a review of steering committee minutes. Interpretation of the output and outcome indicators suggests that the Baseline Studies Program supported a broad range of research, though there were differences in how groups perceived the relevance and legitimacy of project outcomes. Several input, process, and external variables enabled the co-production of trusted science in an emergent boundary organization and contested space; these variables included governance arrangements, leveraged capacities, and the inclusion of traditional knowledge. Challenges to knowledge co-production on the North Slope include logistics, differences in cultures and decision contexts, and balancing trade-offs among perceived credibility, legitimacy, and relevance. Reinforced lessons learned included providing time to foster trust, developing adaptive governance approaches, and building capacity among scientists to translate community concerns into research questions.

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Oil and Gas Potential on the North Slope

Financial Analysts Journal ◽

10.2469/faj.v25.n6.44 ◽

1969 ◽

Vol 25 (6) ◽

pp. 44-56

Author(s):

J.P. Gallagher

Keyword(s):

Oil And Gas ◽

North Slope ◽

The North ◽

Gas Potential

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TURBIDITY CURRENTS: A UNIQUE PART OF NOVA SCOTIA’S AFRICAN GEOLOGICAL HERITAGE

Proceedings of the Nova Scotian Institute of Science (NSIS) ◽

10.15273/pnsis.v47i1.3381 ◽

2012 ◽

Vol 47 (1) ◽

Author(s):

Carolanne Black

Keyword(s):

Nova Scotia ◽

Continental Crust ◽

Oil And Gas ◽

Turbidity Current ◽

Geological Heritage ◽

Turbidity Currents ◽

Submarine Landslides ◽

Grand Banks ◽

The North ◽

Unique Part

Four hundred million years ago, when the supercontinent Pangea wastorn apart, a piece of the continental crust from material that is now partof Africa broke off on the North American side. That piece of Africabecame southern Nova Scotia. The African rock was made of materialdeposited by ancient turbidity currents. Created by submarine landslides,turbidity currents still happen today. Whether evaluating these sedimentaryrocks for oil and gas deposits or for building a city, or studying thepossibility of future turbidity currents along the coast to be prepared fora tsunami, turbidity currents are studied by scientists because they havean impact on Nova Scotians.Keywords: turbidite, turbidity current, Grand Banks earthquake,

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International petroleum and the economic future of Alaska

Polar Record ◽

10.1017/s0032247400061441 ◽

1971 ◽

Vol 15 (97) ◽

pp. 463-478 ◽

Cited By ~ 1

Author(s):

George W. Rogers

Keyword(s):

Oil And Gas ◽

Gold Rush ◽

The State ◽

North Slope ◽

Financial Cost ◽

The North ◽

Bonus Payments ◽

To Come ◽

Tax Payments ◽

Economic Future

The year 1969 was a watershed in Alaska's history. This was the year when the full extent of the international petroleum industry's invasion became apparent to all Alaskans. Most viewed it as a cause of rejoicing and optimism. Overnight, the State of Alaska had become rich as the industry made bonus payments of over $900 million for oil and gas leases on the North Slope, and the prospects loomed of literally hundreds of millions of dollars of annual royalty and tax payments during the decade to come. The state no longer had to worry about where its money was coming from but could concentrate on spending. Private employment climbed, and all the gold rush legends of quick wealth resumed currency. The magnitude of what the oil developers and promoters had accomplished and what they proposed went beyond anything the most enthusiastic Alaskans had ever dreamed of. No physical barrier and no financial cost seemed too great to hinder a prolonged boom. All that Alaskans had to worry about was how to take their share.

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