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Tracing Tectonic Deformation Using the Sedimentary Record: an Overview

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Tracing Tectonic Deformation Using the Sedimentary Record: an Overview Downloaded from http://sp.lyellcollection.org/ by guest on October 2, 2021 Tracing tectonic deformation using the sedimentary record: an overview TOM McCANN I & ALINE SAINTOT 2 1Geologisches Institut, Univer~itiit Bonn, NuJ3allee 8, 53115 Bonn, Germany (e-mail: [email protected]) 2 Vr~e Universiteit, Instituut voor Aardwetenschappen, Tektoniek afdeling, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands Abstract: Tectonic activity, on a range of scales, is a fundamental control on sedimentary activity. The range of structural deformation within a region extends from the plate tectonic scale, governing, for example, rift initiation, to the basin scale, with the formation of basin- bounding faults. Internal basin configuration is also strongly influenced by tectonic activity. However, the relationship between tectonic activity and sedimentation is a complex one, given the many additional factors which can also influence sedimentary activity, including erosion, sediment transport, source area lithology, groundwater chemistry, range of depositional environments, climate, eustasy, and the relative location of an area and its distality to marine influences. In this paper we provide a selective overview of the issues associated with the interlinked themes of tectonics and sedimentation, examining the main basin types forming in both extensional and compressional plate settings. We then review the various models of sedimentation in the selected basins, both on a local and a basinal scale. Finally, we look to the future - providing a series of possible research areas, almost exclusively multidisciplinary, which would help to improve existing models of interlinked sedimen~tectonics systems. Sedimentary basins, and the depositional succes- influence the internal structure of the basin, sions within them, provide the most tangible and segmenting it into related but separate depo- accessible records of the lithospheric, geograph- centres (e.g. Jeanne d'Arc Basin, Tankard et al. ical, oceanographic and ecological developments 1989). These intrabasinal structures also influence which occur in a specific area over a specific the development of topography within a basin by period of time. Tectonic activity, on a range of controlling the location of both highs and lows scales, is a major control on sedimentary activity. which respectively act as potential sediment In recent years there has been an increase in the sources and sinks, and help to determine channel number of studies aiming to unravel the links pathways for sediment (e.g. Alexander & Leeder between tectonic events and sedimentary re- 1987; Leeder & Jackson 1993; Anders & Schlische sponse, both on a basin and intrabasinal scale 1994; Burbank & Pinter 1999). The broad pattern (e.g. Blair & Bilodeau 1988; Heller et al. 1988; of faulting within a basin is determined by both Cas & Busby-Spera 1991; Fisher & Smith 1991; the overall geodynamic setting (i.e. divergent, MacDonald 1991; Williams & Dobb 1993; convergent or strike-slip), and by pre-existing Schwans 1995; Cloetingh et al. 1997; Gupta crustal weaknesses which can strongly influence 1997). fault initiation and location. The range of structural deformation within a Sedimentation results from the interaction of region extends from a plate-tectonic scale (e.g. rift the supply of sediment, its reworking and modi- initiation to oceanic-ridge formation) - affecting fication by physical, chemical and biological the changing pattern of the oceans and con- processes and the availability of accommodation tinents, and controlling the size and nature of space, i.e. the space available for potential sedi- large source areas, sediment transport pathways ment accumulation. Many of these factors have a and the locations of sediment depocentres - down tectonic component. For example, sediment to the basin scale, where tectonics control the supply may vary in volume, composition and formation of major basin-bounding faults which grain size, as well as in the mechanism and rate of determine basin form and location. Additionally, delivery. These variations are largely controlled tectonic activity also controls the internal basin by the processes noted above. Similarly, accom- configuration, for example through the develop- modation space is controlled by sea-level varia- ment of smaller intra-basinal faults (both syn- tion, although relative sea-level changes may thetic and antithetic as well as transfer faults) that have a significant tectonic component. From." MCCANN,T. & SAINTOT, A. (eds) Tracing Tectonic Deformation Using the Sedimentary Record. Geological Society, London, Special Publications, 208, 1-28.0305 8719/03/$15.00 9The Geological Society of London 2003. Downloaded from http://sp.lyellcollection.org/ by guest on October 2, 2021 2 T. McCANN & A. SAINTOT Tectonic activity, therefore, is a very funda- stratigraphic sense) rather than isolated regions. mental control on sedimentation and sediment- Analysis of the sedimentary succession within a ary activity. Similarly, the origin of the basin, therefore, enables us to determine some of sedimentary sequences which are deposited the possible controls on the sedimentary record, within a basin can be related back to the tectonic and at a range of scales ranging from provenance activity which controlled them. The relationship or the examination of sedimentary structures, up between tectonic activity and sedimentation, to the recognition and classification of architec- however, is a complex one, given the large range tural elements and sedimentary sequences, and of factors which can influence sedimentation the reconstruction of depositional environments. within a basin, including: the rate and magnitude Thus, the sedimentary record provides us with a of tectonic activity, the number of faults which unique opportunity to investigate the tectonic are active at any specific time within a basin controls which are of significant interest in basin (including their deformation histories), the rate analysis. and magnitude of sediment production (includ- Our objective in this paper is to provide a ing erosion and sediment transport), the litho- selective review of the linkages between tectonics logical composition of the source area(s), the and sedimentation, and more specifically, studies chemistry of basinal waters, the range of deposi- that have used evidence from the sedimentary tional environments, climate, eustasy, and the record to reconstruct the tectonic history of a location of the depositional area and its distance region. This overview will initially focus on the from marine influences (i.e. continentality). main types of tectonic settings and the sediments Given the inherent variability of all of these that are found in conjunction with them. Subse- factors (together with the fact that many of them quent sections will examine the various models in are interlinked, e.g. climate and erosion), any use, summarizing with an overview of the current basin system is, by default, a complex one. gaps in our knowledge and suggestions for future Therefore, modelling of the evolution of the research areas. basin infill is difficult, since each individual basin will have its own particular tectonosedimentary signature. Additionally, there is the problem of Basin classification differentiating between the various factors which Basin classification schemes vary according to influence the composition and distribution of the the particular needs of the user. For example, sedimentary succession within a basin. schemes which originate in the field of hydro- Changes in our understanding of the inter- carbon exploration (e.g. Kingston et aL 1983a, b) relationship of tectonic activity and sedimenta- are designed to be used in a predictive manner tion have occurred in several disciplines which and tend to be limited to the main basin types play a central role in basin analysis. These (particularly those of interest to the hydrocarbon include plate-tectonic theory (e.g. Cox & Hart exploration industry). In contrast, academic 1986), new geodynamic models, as well as a classification schemes (e.g. Ingersoll & Busby revolution in our understanding of modern 1995) tend to be more complex, since they tend depositional systems, and consequent major towards inclusivity and completeness (Table 1). advances in the sophistication of actualistic In this latter scheme, basin types are broadly depositional models (e.g. Walker & James grouped into those which are formed in divergent 1992; Miall 1997; Reading 1998; Leeder 1999). plate geodynamic settings (including continental Petrological models relating sediment composi- rift basins), those which occur in intraplate tion, especially sand and sandstone, to plate settings (including intracratonic basins, oceanic tectonic settings have also been developed (e.g. islands and dormant ocean basins), those which Dickinson & Suczek 1979; Dickinson 1988; form in convergent plate geodynamic settings Bahlburg & Floyd 1999), and this work has been (including arc-related basins, foreland basins, extended into the fields of sedimentary and trenches), those which are found in geochemistry (e.g. Bhatia 1983; Roser & Korsch transform settings (including transtensional and 1986; Clift et al. 2001) and single grain analysis transpressional tectonics) and a final group (e.g.M. Smith & Gehrels 1994; G6tze & which includes basins located in hybrid settings Zimmerle 2000). New exploration techniques, (Ingersoll & Busby 1995). In our overview of especially seismic and sequence stratigraphy
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