Department of Oceanography
Dalhousie University
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Halifax, NS, B3H 4R2
Canada
You are here: Dalhousie Geodynamics: Chris Beaumont: Publications
Research Contributions
Refereed Journal and Conference Publications (2000 - 2013)
Refereed Journal and Conference Publications (1990 - 2000)
Refereed Journal and Conference Publications (before 1990)
Non-Refereed Publications
Discussion
Book
Reports
Papers Arising Research that I in part supervised
Papers Arising From Work of the Geodynamics Group
We have investigated the role of crustal channel flows in the evolution of the H-T orogen. The most significant result is the demonstration that gravitationally-driven flows that squeeze out and expel hot low-viscosity mid-crust, containing a small fraction of partial melt, from beneath the plateau toward the surrounding foreland are compatible with a range of observations. In particular, the relationship between the Greater Himalayan Sequence and its flow between the normal- and thrust-sense South Tibetan Detachment and Main Central Thrust systems has the characteristics of an erosionally-exhumed channel. (Beaumont et al., Nature 2001; Beaumont et al., 2004, Jour. Geophys. Res.; Jamieson et al., 2004, Jour. Geophys. Res. (see list below for complete references)). These papers received ?Best Paper? awards from Geological Society of America and Geological Association of Canada. Our most recent contributions to this theme are Beaumont et al., 2006; Jamieson et al., 2006; and Medvedev and Beaumont, 2006, all Geol. Soc. London Spec Publ.
In a series of papers starting with Willett et al., 1993, Geology (GAC Structure and Tectonics Division Best Paper award) we have used numerical models to investigate the deformation of continental crust in continent-continent collision zones above subducting mantle lithosphere. The results expanded on critical wedge concepts and demonstrated the formation of asymmetric doubly (or bi-)vergent orogens with geometries that depend on the strength of the frictional or viscous coupling between the crustal layer and the underlying lithosphere (Beaumont et al., 1994, Tectonophysics; Beaumont and Quinlan, 1994, Geophys. J. Int.) These models were purely mechanical in the early work, but were later expanded to coupled thermal-mechanical cases which permitted the investigation of metamorphism, P-T-t paths, and the consequences of radioactive heating on crustal weakening and the promotion of viscous flow (Jamieson et al., 1997, Geol. Soc. London). The model was also shown to apply to large hot orogens (Jamieson et al., 2002, J. Metamorphic Geol.), to the formation of plateaus by crustal thermal weakening (Vanderhaeghe et al., 2003, Geophys. J. Int.), and to crustal channel flows as outlined above in A. Other related papers include Beaumont et al., 1999 and Ellis et al. 1999, Jour. Geophys. Res.; Pfiffner et al. 2000, Tectonics; and Beaumont et al., 2000, Jour. Geophys. Res.
Our most recent research under this theme concerns the creation and exhumation of (U)HP metamorphic rocks (Warren et al., in press; sub) during the transition from oceanic subduction to continental collision, and continent-continent collision involving continents comprising a strong cratonic interior amalgamated with weaker exterior terranes (Jamieson et al., 2007, Tectonics; Beaumont et al., sub., Lithoprobe).
Beaumont et al., 1992, in: K. McClay ed., Thrust Tectonics, 1-18, is a paper that was in the vanguard of research on the coupling between tectonics and surface processes; the quantitative demonstration that erosion (and sedimentation) have important feedback effects on tectonics through the removal (and addition) of material weight which modifies tectonic states of stress and the ensuing deformation. Even today this is a significant research topic, particularly concerning investigations of the interactions among climate, surface processes and tectonics. We have continued related research, e.g. Kooi and Beaumont, 1994, 1996, Jour. Geophys. Res., papers in A above, and most recently in regard to the feedback of erosion and sedimentation in thrust-and-fold belts at scales that are smaller than the entire wedge (Stockmal et al., in press)
Salts (halite and other evaporites) are particularly weak materials that are commonly involved in large scale deformation of passive margin sedimentary sequences. We have contributed to this research by developing numerical models that allow us to investigate large deformation of sedimentary sequences involving salt layers (Gemmer et al., 2004, 2005, Basin Research; Ings et al. GCSSEPM Conference Volume 2005). This research provides both an improved understanding of stability of these systems, and the way large salt structures evolve. The results are of significant interest to the petroleum industry because the corresponding natural structures are among the most important hydrocarbon traps. Understanding how and when such traps occur helps develop petroleum 'play' concepts, particularly in regard to risk evaluation. Current research under this theme includes the study of Scotian Basin salt tectonics (see Section 1E ii of the nomination form), development of new models for the formation of salt minibasins, and studies of deep-water fold belts formed by gravitational detachment above salt.
This work is reported in a series of papers published since 2002 and coauthored by Huismans, Beaumont, Buiter and Simon. The goal was an improved understanding of the deformation styles of the lithosphere during stretching as a precursor to continental breakup and the relationship of these styles to lithospheric properties. Huismans and Beaumont (2002, Geology; 2003, Jour. Geophys Res.) demonstrate that strain-softening can lead to asymmetric extension resulting in asymmetric conjugate rifted continental margins. Huismans et al. (2005, Jour. Geophys. Res.) provides an in-depth analysis of numerical model rifting styles and shows that these styles can be predicted by the minimum rate of work principle. In simple models this reduces to the competition between the plastic rate of work in the brittle lithosphere and the viscous rate of work in the ductile lithosphere. The principle provides a good prediction of mode selection during rifting in the numerical models and this approach has been extended to a wider range of modes by Buiter et al. (2008, Jour.Geophys. Res.) Although it cannot be proven that the Earth obeys the minimum rate of work principle, we argue that this approach to mode selection should be used to classify different types of rifted margins and to test in a qualitative way whether minimum rate of work explains the modes that were selected. Huismans and Beaumont (2008), Geology) presents a simple general model for the creation of the extremely wide rifted continental margins observed in the South Atlantic and elsewhere. The model predicts the tripartite division of the margin into Proximal, Sag and Distal regions and explains the character of these regions.
Articles in Refereed Publications (2000 - 2013)
Refereed Journal and Conference Publications (1990 - 2000)
Refereed Journal and Conference Publications
(before 1990)
Papers Arising From Research that I in part supervised
Papers Arising From Work of the Geodynamics Group
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