- Home
- A-Z Publications
- Basin Research
- Previous Issues
- Volume 20, Issue 3, 2008
Basin Research - Volume 20, Issue 3, 2008
Volume 20, Issue 3, 2008
-
-
Pro‐ vs. retro‐foreland basins
Authors M. Naylor and H. D. SinclairABSTRACTAlpine‐type mountain belts formed by continental collision are characterised by a strong cross‐sectional asymmetry driven by the dominant underthrusting of one plate beneath the other. Such mountain belts are flanked on either side by two peripheral foreland basins, one over the underthrust plate and one over the over‐riding plate; these have been termed pro‐ and retro‐foreland basins, respectively. Numerical modelling that incorporates suitable tectonic boundary conditions, and models orogenesis from growth to a steady‐state form (i.e. where accretionary influx equals erosional outflux), predicts contrasting basin development to these two end‐member basin types. Pro‐foreland basins are characterised by: (1) Accelerating tectonic subsidence driven primarily by the translation of the basin fill towards the mountain belt at the convergence rate. (2) Stratigraphic onlap onto the cratonic margin at a rate at least equal to the plate convergence rate. (3) A basin infill that records the most recent development of the mountain belt with a preserved interval determined by the width of the basin divided by the convergence rate. In contrast, retro‐foreland basins are relatively stable, are not translated into the mountain belt once steady‐state is achieved, and are consequently characterised by: (1) A constant tectonic subsidence rate during growth of the thrust wedge, with zero tectonic subsidence during the steady‐state phase (i.e. ongoing accretion‐erosion, but constant load). (2) Relatively little stratigraphic onlap driven only by the growth of the retro‐wedge. (3) A basin fill that records the entire growth phase of the mountain belt, but only a condensed representation of steady‐state conditions. Examples of pro‐foreland basins include the Appalachian foredeep, the west Taiwan foreland basin, the North Alpine Foreland Basin and the Ebro Basin (southern Pyrenees). Examples of retro‐foreland basins include the South Westland Basin (Southern Alps, New Zealand), the Aquitaine Basin (northern Pyrenees), and the Po Basin (southern European Alps). We discuss how this new insight into the variability of collisional foreland basins can be used to better interpret mountain belt evolution and the hydrocarbon potential of these basins types.
-
-
-
Trench‐forearc interactions reflected in the sedimentary fill of Talara basin, northwest Peru
Authors Andrea Fildani, Angela M. Hessler and Stephan A. GrahamABSTRACTExceptional exposure of the forearc region of NW Peru offers insight into evolving convergent margins. The sedimentary fill of the Talara basin spans the Cretaceous to the Eocene for an overall thickness of 9000 m and records within its stratigraphy the complicated history of plate interactions, subduction tectonics, terrane accretion, and Andean orogeny. By the early Tertiary, extensional tectonism was forming a complex horst and graben system that partitioned the basin into a series of localized depocentres. Eocene strata record temporal transitions from deltaic and fluvial to deep‐water depositional environments as a response to abrupt, tectonically controlled relative sea‐level changes across those depocentres. Stratigraphic and provenance data suggest a direct relationship between sedimentary packaging and regional tectonics, marked by changes in source terranes at major unconformities. A sharp shift is recognized at the onset of deepwater (bathyal) sedimentation of the Talara Formation, whose sediments reflect an increased influx of mafic material to the basin, likely related to the arc region. Although the modern topography of the Amotape Mountains partially isolates the Talara basin from the Lancones basin and the Andean Cordillera to the east, provenance data suggest that the Amotape Mountains were not always an obstacle for Cordilleran sediment dispersal. The mountain belt intermittently isolated the Talara basin from Andean‐related sediment throughout the early Tertiary, allowing arc‐related sediment to reach the basin only during periods of subsidence in the forearc region, probably related to plate rearrangement and/or seamounts colliding with the trench. Intraplate coupling and/or partial locking of subduction plates could be among the major causes behind shifts from contraction to extension (and enhanced subduction erosion) in the forearc region. Eventually, collisional tectonic and terrane accretion along the Ecuadorian margin forced a major late‐Eocene change in sediment dispersal.
-
-
-
Giant submarine collapse of a carbonate platform at the Turonian–Coniacian transition: The Ayabacas Formation, southern Peru
Authors Pierre Callot, Thierry Sempere, Francis Odonne and Emmanuel RobertABSTRACTThe Ayabacas Formation of southern Peru is an impressive unit formed by the giant submarine collapse of the mid‐Cretaceous carbonate platform of the western Peru back‐arc basin (WPBAB), near the Turonian–Coniacian transition (∼90–89 Ma). It extends along the southwestern edge of the Cordillera Oriental and throughout the Altiplano and Cordillera Occidental over >80 000 km2 in map view, and represents a volume of displaced sediments of >10 000 km3. The collapse occurred down the basin slope, i.e. toward the SW. Six zones are characterised on the basis of deformational facies, and a seventh corresponds to the northeastern ‘stable’ area (Zone 0). Zones 1–3 display increasing fragmentation from NE to SW, and are composed of limestone rafts and sheets embedded in a matrix of mainly red, partly calcareous and locally sandy, mudstones to siltstones. In contrast, in Zones 4 and 5 the unit consists only of displaced and stacked limestone masses forming a ‘sedimentary thrust and fold system’, with sizes increasing to the southwest. In Zone 6, the upper part of the limestone succession consists of rafts and sheets stacked over the regularly bedded lower part. The triggering of this extremely large mass wasting clearly ensued from slope creation, oversteepening and seismicity produced by extensional tectonic activity, as demonstrated by the observation of synsedimentary normal faults and related thickness variations. Other factors, such as pore pressure increases or lithification contrasts probably facilitated sliding. The key role of tectonics is strengthened by the specific relationships between the basin and collapse histories and two major fault systems that cross the study area. The Ayabacas collapse occurred at a turning point in the Central Andean evolution. Before the event, the back‐arc basin had been essentially marine and deepened to the west, with little volcanic activity taking place at the arc. After the event, the back‐arc was occupied by continental to near‐continental environments, and was bounded to the southwest by a massive volcanic arc shedding debris and tuffs into the basin.
-
-
-
U–Pb zircon and 40Ar–39Ar K‐feldspar dating of syn‐sedimentary volcanism of the Neoproterozoic Maricá Formation: constraining the age of foreland basin inception and inversion in the Camaquã Basin of southern Brazil
ABSTRACTNew U–Pb zircon and 40Ar–39Ar K‐feldspar data are presented for syn‐sedimentary volcanogenic rocks from the Neoproterozoic Maricá Formation, located in the southern Brazilian shield. Seven (of nine) U–Pb sensitive high‐resolution ion microprobe analyses of zircons from pyroclastic cobbles yield an age of 630.2±3.4 Ma (2σ), interpreted as the age of syn‐sedimentary volcanism, and thus of the deposition itself. This result indicates that the Maricá Formation was deposited during the main collisional phase (640–620 Ma) of the Brasiliano II orogenic system, probably as a forebulge or back‐bulge, craton‐derived foreland succession. Thus, this unit is possibly correlative of younger portions of the Porongos, Brusque, Passo Feio, Abapã (Itaiacoca) and Lavalleja (Fuente del Puma) metamorphic complexes. Well‐defined, step‐heating 40Ar–39Ar K‐feldspar plateau ages obtained from volcanogenic beds and pyroclastic cobbles of the lower and upper successions of the Maricá Formation yielded 507.3±1.8 Ma and 506.7±1.4 Ma (2σ), respectively. These data are interpreted to reflect total isotopic resetting during deep burial and thermal effects related to magmatic events. Late Middle Cambrian cooling below ca. 200 °C, probably related to uplift, is tentatively associated with intraplate effects of the Rio Doce and/or Pampean orogenies (Brasiliano III system). In the southern Brazilian shield, these intraplate stresses are possibly related to the dominantly extensional opening of a rift or a pull‐apart basin, where sedimentary rocks of the Camaquã Group (Santa Bárbara and Guaritas Formations) accumulated.
-
-
-
Late Carboniferous foreland basin formation and Early Carboniferous stretching in Northwestern Europe: inferences from quantitative subsidence analyses in the Netherlands
ABSTRACTThe large thickness of Upper Carboniferous strata found in the Netherlands suggests that the area was subject to long‐term subsidence. However, the mechanisms responsible for subsidence are not quantified and are poorly known. In the area north of the London Brabant Massif, onshore United Kingdom, subsidence during the Namurian–Westphalian B has been explained by Dinantian rifting, followed by thermal subsidence. In contrast, south and east of the Netherlands, along the southern margin of the Northwest European Carboniferous Basin, flexural subsidence caused the development of a foreland basin. It has been proposed that foreland flexure due to Variscan orogenic loading was also responsible for Late Carboniferous subsidence in the Netherlands. In the first part of this paper, we present a series of modelling results in which the geometry and location of the Variscan foreland basin was calculated on the basis of kinematic reconstructions of the Variscan thrust system. Although several uncertainties exist, it is concluded that most subsidence calculated from well data in the Netherlands cannot be explained by flexural subsidence alone. Therefore, we investigated whether a Dinantian rifting event could adequately explain the observed subsidence by inverse modelling. The results show that if only a Dinantian rifting event is assumed, such as is found in the United Kingdom, a very high palaeowater depth at the end of the Dinantian is required to accommodate the Namurian–Westphalian B sedimentary sequence. To better explain the observed subsidence curves, we propose (1) an additional stretching event during the Namurian and (2) a model incorporating an extra dynamic component, which might well explain the very high wavelength of the observed subsidence compared with the wavelength of the predicted flexural foreland basin.
-
-
-
Temporal constraints on basin inversion provided by 3D seismic and well data: a case study from the South Viking Graben, offshore Norway
Authors C. A‐L. Jackson and E. LarsenABSTRACTThree‐dimensional (3D) seismic, well and biostratigraphic data are integrated to determine the timing of inversion on the hangingwall of the South Viking Graben, offshore Norway. Within the study area two, NW–SE to NE–SW trending normal faults are developed which were active during a Late Jurassic rift event. In the hangingwall of these faults asymmetric, 2–5 km wide anticlines are developed which trend parallel to the adjacent faults and are interpreted as growth folds formed in response to compressional shortening (inversion) of the syn‐rift basin‐fill. Marked thickness variations are observed in Late Jurassic and Early Cretaceous growth strata with respect to the inversion‐related folds, with seismic data indicating onlap and thinning of these units across the folds. In addition, well data suggests that not only are erosional surfaces only locally developed towards the crests of the folds, but these surfaces may also truncate underlying flooding surfaces towards the fold crests. Taken together, these observations indicate that inversion and growth of inversion‐related structures initiated in the late Early Volgian and continued until the Late Albian. Furthermore, it is demonstrated that individual folds amplified and propagated laterally through time, and that fold growth was not synchronous across the study area. This study demonstrates that the temporal evolution of structures associated with the inversion of sedimentary basins can be accurately determined through the integration of 3D seismic, well and biostratigraphic data. Furthermore, this study has local implications for constraining the timing of inversion within the South Viking Graben during the Late Mesozoic.
-
-
-
Role of pore pressure generation in sediment transport within half‐grabens
Authors Yao You and Mark PersonABSTRACTSediment transport and overpressure generation are coupled primary through the impact of effective stress on subsidence and compaction. Here, we use mathematical modeling to explore the interactions between groundwater flow and diffusion‐controlled sediment transport within alluvial basins. Because of lateral variation in permeability, proximal basin facies will have pore pressure close to hydrostatic levels while distal fine‐grained facies can reach near lithostatic levels. Lateral variation in pore pressure leads to differential compaction, which deforms basins in several ways. Differential compaction reduces basin size, bends isochron surfaces across the sand–clay interface, restricts basinward progradation of sand facies, and reduces the amplitude of oscillation in the lateral position of the sand–clay interface especially in the deepest part of the section even when temporal sediment supply are held constant. Overpressure generation was found to be sensitive to change in sediment supply in permeable basins (at least 10−17 m2 in our model). We found that during basin evolution, temporal variations in overpressure and sediment supply fluctuations are not necessarily in phase with each other, especially in tight (low permeability) basins (<10−17 m2 in our model).
-
-
-
‘LOSCS’ Lateral Offset Stacked Channel Simulations: Towards geometrical modelling of turbidite elementary channels
More LessABSTRACTTurbidite hydrocarbon reservoirs are complex features, that need to be described in detail and represented as clearly as possible. The morphology and internal distribution of elementary distributary channels are dependent on depositional settings, leading to diverse arrangements at different scales. Reservoir modelling usually requires a description of sedimentary heterogeneity on a scale smaller than that given by seismic resolution. This is because seismic data only display the outside geometry of their lateral stack, i.e. a turbidite fairway. Complexes of Laterally Offset Stacked Turbidite Channels (LOSCs) also require a description based on the scales of individual channel bodies. The most common representation of channels in a fairway is by stochastic object modelling; i.e. populating the observed fairway with realistic forms representing individual channels, but with no established consistency between the individual channels. On the other hand, one essential characteristic of LOSCs is that it evolves by progressive migration laterally and/or downdip. Stochastic object modelling provides an inadequate representation of this progressive evolution, and consequently, a poor rendering of the heterogeneity distribution in the reservoir. The method we propose consists of defining a realistic succession of individual channels that can accurately build the fairway observed on seismic. ‘Realism’ is defined using criteria from the shape of individual channels, and based on the amount of displacement necessary between successive episodes. Depending on seismic resolution, the system can be constrained by one or several positions of individual channels (the most recent position of the channel is often filled with shale, therefore visible on seismic and usable as a control point). The final result is a deterministic succession of channels laterally stacked to build the seismically observed envelope. Even with no calibration, the resulting architecture respects the general ‘texture’ of the complex and provides a better simulation of flow pathways than that achieved by random object modelling.
-
-
-
Morphology and distribution of Oligocene and Miocene pockmarks in the Danish North Sea – implications for bottom current activity and fluid migration
Authors K. J. Andresen, M. Huuse and O. R. ClausenABSTRACTThis study gives the first description of 33 mid‐Oligocene and 646 late Miocene pockmarks mapped in the Danish part of the central North Sea. The pockmarks are all highly elongated, with average long‐ and short axes of 2.5 km and 700 m, and average internal depth of 30 m. The Miocene pockmarks strike 140–160° while the Oligocene pockmarks strike 100–105°; paralleling the strike of the major Miocene and Oligocene clinoforms on which they occur. In cross‐sections, the pockmarks appear as U‐, V‐ and W‐shaped or tabular depressions. Based on their geometry and degree of symmetry, three distinct pockmark groups have been distinguished: (A) 58% of the pockmarks are symmetrical, ellipsoidal depressions; (B) 40% are asymmetrical, lunate depressions; and (C) 2% comprise asymmetrical ring‐shaped depressions. Group A pockmarks are interpreted as representative for the first stage in the pockmark development, only influenced by fluid expulsion and subsequent erosion by bottom currents. Group B pockmarks are influenced by bottom current erosion, current and gas winnowing and possibly authigenic carbonate precipitation. Group C pockmarks represent a further development from Group B pockmarks with further winnowing, carbonate precipitation and removal of seafloor sediment to form the ring‐shape. Current erosion has exerted the major influence on the final geometry of 83% of the pockmarks. The pockmarks occur above gas‐mature Jurassic source rocks, modelled to be in the generative window during the late Miocene, and thermogenic gas is suggested as the main fluid involved in the pockmark formation. The timing of gas expulsion from the Jurassic source rocks in combination with loading imposed to the basin by the progradational Miocene clinoforms are interpreted as the main factors controlling the timing and location of the pockmarks. The pockmarks thus tell a story of thermogenic gas venting to the surface and paleo‐current scour of the seabed in the eastern part of the central North Sea during the mid Oligocene and late Miocene.
-
Volumes & issues
-
Volume 36 (2024)
-
Volume 35 (2023)
-
Volume 34 (2022)
-
Volume 33 (2021)
-
Volume 32 (2020)
-
Volume 31 (2019)
-
Volume 30 (2018)
-
Volume 29 (2017)
-
Volume 28 (2016)
-
Volume 27 (2015)
-
Volume 26 (2014)
-
Volume 25 (2013)
-
Volume 24 (2012)
-
Volume 23 (2011)
-
Volume 22 (2010)
-
Volume 21 (2009)
-
Volume 20 (2008)
-
Volume 19 (2007)
-
Volume 18 (2006)
-
Volume 17 (2005)
-
Volume 16 (2004)
-
Volume 15 (2003)
-
Volume 14 (2002)
-
Volume 13 (2001)
-
Volume 12 (2000)
-
Volume 11 (1999)
-
Volume 10 (1998)
-
Volume 9 (1997)
-
Volume 8 (1996)
-
Volume 7 (1994)
-
Volume 6 (1994)
-
Volume 5 (1993)
-
Volume 4 (1992)
-
Volume 3 (1991)
-
Volume 2 (1989)
-
Volume 1 (1988)