Assessment of the effect of mass-transport deposits on fault propagation in Penobscot area, offshore Nova Scotia

2018 ◽  
Vol 477 (1) ◽  
pp. 121-131 ◽  
Author(s):  
Tuviere Omeru ◽  
Samson I. Bankole ◽  
Byami A. Jolly ◽  
Obafemi S. Seyi ◽  
Joses B. Omojola
Keyword(s):  
Nova Scotia ◽  
Mass Transport ◽  
Three Dimensional ◽  
Seismic Facies ◽  
Thickness Variation ◽  
Fault Propagation ◽  
Seismic Profiles ◽  
History Of ◽  
Throw Distance ◽  
Mass Transport Deposits

AbstractThree-dimensional (3D) seismic data and well logs from the Penobscot area, located within the Scotian Basin offshore Nova Scotia, are used to assess the role of mass-transport deposits (MTDs) on fault propagation. Four MTDs characterized by chaotic seismic facies were mapped, with the earliest hosted by the Late Cretaceous–Recent Dawson Canyon Formation and latest three hosted by the Banquereau Formation. Two types of faults were also mapped. R-faults are regional faults that cut across all the interpreted MTDs in the study area, while P-faults are polygonal faults that cut across MTDs 2 and 3 but tip out at the basal surfaces of MTDs 4 and 2. Representative seismic profiles and isochron maps of the MTDs and throw–depth (T–z) and throw–distance (T–x) plots allows us to distinguish the families and propagation history of the faults. Our results show that fault propagation is not affected by the presence or thickness variation of MTDs, and is also unaffected by lithological contrast in the Penobscot area of the Nova Scotian Shelf.

Natural History of Carotid Atherosclerosis in Relation to the Hemodynamic Environment

Angiology ◽  
2016 ◽  
Vol 68 (2) ◽  
pp. 109-118 ◽  
Author(s):  
Antonis I. Sakellarios ◽  
Paschalis Bizopoulos ◽  
Michail I. Papafaklis ◽  
Lambros Athanasiou ◽  
Themis Exarchos ◽  
...  
Keyword(s):  
Blood Flow ◽  
Natural History ◽  
Mass Transport ◽  
Carotid Atherosclerosis ◽  
Low Density Lipoprotein ◽  
Three Dimensional ◽  
Density Lipoprotein ◽  
Magnetic Resonance Data ◽  
History Of ◽  
Plaque Growth

Carotid atherosclerosis may lead to devastating clinical outcomes such as stroke. Data on the value of local factors in predicting progression in carotid atherosclerosis are limited. Our aim was to investigate the association of local endothelial shear stress (ESS) and low-density lipoprotein (LDL) accumulation with the natural history of atherosclerotic disease using a series of 3 time points of human magnetic resonance data. Three-dimensional lumen/wall reconstruction was performed in 12 carotids, and blood flow and LDL mass transport modeling were performed. Our results showed that an increase in plaque thickness and a decrease in lumen size were associated with low ESS and high LDL accumulation in the arterial wall. Low ESS (odds ratio [OR]: 2.99; 95% confidence interval [CI]: 2.31-3.88; P < .001 vs higher ESS) and high LDL concentration (OR: 3.26; 95% CI: 2.44-4.36; P < .001 vs higher LDL concentration) were significantly associated with substantial local plaque growth. Low ESS and high LDL accumulation both presented a diagnostic accuracy of 67% for predicting plaque growth regions. Modeling of blood flow and LDL mass transport show promise in predicting progression of carotid atherosclerosis.

scholarly journals Seismic expression of depositional elements associated with a strongly progradational shelf margin: northern Santos Basin, southeastern Brazil

2016 ◽  
Vol 46 (4) ◽  
pp. 585-603 ◽  
Author(s):  
Fábio Berton1* ◽  
◽  
Fernando Farias Vesely
Keyword(s):  
Mass Transport ◽  
Progressive Increase ◽  
Seismic Facies ◽  
Southeastern Brazil ◽  
Submarine Channels ◽  
Base Level ◽  
Equilibrium Profile ◽  
Mass Transport Deposits ◽  
Shelf Margin ◽  
Depositional Elements

ABSTRACT: Seismic facies analysis and seismic geomorphology are important tools for the analysis of depositional elements in subsurface. This paper aimed to investigate the character and genesis of depositional elements and erosive features associated with an Eocene progradational shelf margin in northern Santos Basin. Identified seismic facies are interpreted as shelf-margin deltas/shoreface deposits, tangential (oblique) clinoforms, sigmoidal clinoforms, topset reflectors, mass-transport deposits and turbidites. These facies are grouped into four associations representing periods of relatively constant environmental conditions. Association 1 is composed of shelf-margin deltas/shoreface deposits, tangential clinoforms and extensive sand-rich turbidites disposed as submarine channels and frontal splays. A progressive increase in clinoform angle within this association has been identified, culminating in high-relief sigmoidal clinoforms with less voluminous turbidites of facies association 2. Association 3 is composed by subparallel to divergent topset reflectors, interpreted as continental to shelfal deposits placed during base-level rises. These are always truncated basinward by slump scars, formed as a consequence of sediment overload at the shelf margin during aggradations. Association 4 is composed of sigmoidal clinoforms, mass-transport deposits and turbidites. Early clinoforms are steeper as a consequence of the topography of the slump scars. Subsequently, dip angles become progressively gentler as the system approach to the equilibrium profile. The steep physiography was favorable for canyon incision, which played an important role in turbidite deposition. Mass-transport deposits, formed subsequent to slope collapse, are composed of mud-rich diamictites, and show strong internal deformation.

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 Geostatistical characterization of internal structure of mass-transport deposits from seismic reflection images and borehole logs

2019 ◽  
Vol 221 (1) ◽  
pp. 318-333
Author(s):  
Jonathan Ford ◽  
Angelo Camerlenghi
Keyword(s):  
Mass Transport ◽  
Internal Structure ◽  
Seismic Reflection ◽  
Slope Failure ◽  
Random Medium ◽  
Seismic Facies ◽  
Strain History ◽  
Borehole Data ◽  
Mass Transport Deposits ◽  
Scale Length

SUMMARY Seismic reflection images of mass-transport deposits often show apparently chaotic, disorded or low-reflectivity internal seismic facies. The lack of laterally coherent reflections can prevent horizon-based interpretation of internal structure. This study instead inverts for geostatistical parameters which characterize the internal heterogeneity of mass-transport deposits from depth-domain seismic reflection images. A Bayesian Markov Chain Monte Carlo inversion is performed to estimate posterior probability distributions for each geostatistical parameter. If the internal heterogeneity approximates an anisotropic von Kármán random medium these parameters can describe the structural fabric of the imaged mass-transport deposit in terms of lateral and vertical dominant scale lengths and the Hurst number (roughness). To improve the discrimination between vertical and lateral dominant scale lengths an estimate of the vertical dominant scale length from a borehole is used as a prior in the inversion. The method is first demonstrated on a synthetic multichannel seismic reflection image. The vertical and lateral dominant scale lengths are estimated with lower uncertainty when data from a synthetic borehole data are included. We then apply the method to a real data example from Nankai Trough, offshore Japan, where a large mass-transport deposit is imaged in a seismic profile and penetrated by a borehole. The results of the inversion show a downslope shortening in lateral scale length, consistent with progressive down-slope disaggregation of the mass-flow during transport. The dominant scale lengths can be used as a proxy for strain history, which can improve understanding of post-failure dynamics and emplacement of subacqueous mass-movements, important for constraining the geohazard potential from future slope failure.

scholarly journals Enabling high-accuracy, position monitoring of Sable Island through the Nova Scotia Coordinate Referencing System

2016 ◽  
Vol 48 (2) ◽  
pp. 265 ◽  
Author(s):  
Jason Bond
Keyword(s):  
Nova Scotia ◽  
Positive Impact ◽  
Three Dimensional ◽  
Engineering Work ◽  
History Of ◽  
Main Station ◽  
First Time ◽  
Position Monitoring ◽  
Global Reference Frame

Since 1968, the Province of Nova Scotia has carried out a mandate of providing coordinate referencing infrastructure for its citizens. The current infrastructure is known as the Nova Scotia Coordinate Referencing System (NSCRS) and allows property boundaries, engineering works, and natural features to be spatially related within the Province, including Sable Island. Traditionally, thousands of survey monuments across the Province provided access to the coordinate referencing system for surveying and engineering work. Of the original 23,000 monuments installed in the 1970s and 1980s, many have been destroyed by natural occurrences or human activities. In the case of Sable Island, most have been enveloped by sand or the sea.  In 2013, the Province began implementing a modernized strategy for delivering coordinate referencing services to its citizens using permanent GPS stations. This technology was installed at Main Station on Sable Island in June of 2014. This GPS infrastructure has already had a positive impact by:a)Allowing, for the first time, the three dimensional position of Sable Island (specifically Main Station) to be monitored with millimeter level accuracy b)Enabling Light Detection and Ranging (LiDAR) and aerial photography surveys to be consistently referenced within a global reference frame; andc)Providing quick and accurate positioning of natural features around the island with millimeter level accuracy and consequently enabling long term, position trends of these features (e.g., Bald Dune) to be determined.Each of these topics is discussed and a history of the NSCRS on Sable Island is presented. 

Sea Urchins and Circuses: The Modernist Natural Histories of Jean Painlevé and Alexander Calder

2018 ◽  
Vol 13 (2) ◽  
pp. 187-211
Author(s):  
Patricia E. Chu
Keyword(s):  
New Media ◽  
Sea Urchins ◽  
Life Sciences ◽  
Three Dimensional ◽  
Machine Age ◽  
Avant Garde ◽  
History Of ◽  
And Performance ◽  
The One ◽  
Natural Historian

The Paris avant-garde milieu from which both Cirque Calder/Calder's Circus and Painlevé’s early films emerged was a cultural intersection of art and the twentieth-century life sciences. In turning to the style of current scientific journals, the Paris surrealists can be understood as engaging the (life) sciences not simply as a provider of normative categories of materiality to be dismissed, but as a companion in apprehending the “reality” of a world beneath the surface just as real as the one visible to the naked eye. I will focus in this essay on two modernist practices in new media in the context of the history of the life sciences: Jean Painlevé’s (1902–1989) science films and Alexander Calder's (1898–1976) work in three-dimensional moving art and performance—the Circus. In analyzing Painlevé’s work, I discuss it as exemplary of a moment when life sciences and avant-garde technical methods and philosophies created each other rather than being classified as separate categories of epistemological work. In moving from Painlevé’s films to Alexander Calder's Circus, Painlevé’s cinematography remains at the forefront; I use his film of one of Calder's performances of the Circus, a collaboration the men had taken two decades to complete. Painlevé’s depiction allows us to see the elements of Calder's work that mark it as akin to Painlevé’s own interest in a modern experimental organicism as central to the so-called machine-age. Calder's work can be understood as similarly developing an avant-garde practice along the line between the bestiary of the natural historian and the bestiary of the modern life scientist.

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