Print this pageBasin-Scale Salt Tectonic Processes from the North-Central Scotian Margin: Insights from Integrated Regional 2-D Seismic Interpretation and 4d Physical Experiments
J. Adam1, C. Krezsek3, C. MacDonald2, C. Campbell2, J. Cribb2, M. Nedimovic2, and D. Grujic2
1Geology, Royal Holloway University of London, Egham, United Kingdom
2Earth Sciences, Dalhousie University, Halifax, NS, Canada
3Hydro Oil & Global Exploration, Oslo, Norway
The complex salt deformation styles characterizing the diverse Scotian Basin salt provinces are the result of basement topography, salt thickness, and sedimentation during the Jurassic and Cretaceous. Exploration concepts developed in salt basins around the Atlantic margins cannot be adapted reliably to the Scotian Margin. Consequently, new tectonostratigraphic concepts of the Scotian Margin must address the unique basin characteristics including palaeogeography, sediment supply, and rift basin geometry.
Regional seismic sections of the GXT NovaSpan data allow structural and analogue modelling of regional transects extending from the shelf to the deepwater. The Salt Dynamics Group utilizes physical experiments to analyze salt tectonic processes and their interaction with depositional systems from early post-rift salt mobilization to late post-rift allochthonous salt complexes. 4D strain data and experiment sections enable mechanical modelling of fault and salt tectonic processes. Salt tectonic concepts derived from our experiments relate characteristic salt structures to the palaeo-depositional environment and kinematic stages of the basin evolution.
Our study demonstrate that the Scotian salt provinces differ strongly from the salt basins of the Gulf of Mexico and the younger South Atlantic salt basins. Low mechanical coupling of the sediment overburden due to thick original salt in narrow linked rift basins has favored rapid down-building and sediment aggradation rather than progradation in the early post-rift stage. Salt mobilization started in the Laurentian Basin and propagated in southward direction along the margin due to shelf-parallel sediment transport sourced by the Laurentian Fan from the NE. This depositional pattern has led to diachronous salt extrusion shown by southward younging of allochthonous salt complexes in the North-Central Scotian Basin.
AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas