bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanics of basin inversion from worldwide examples
Authors: Lowell James D. 
Published: April 2008

Abstract
Inversion is dependent on pre-existing basin configuration in the initial subsidence, usually extensional phase, and the resolution of compressional forces in the later shortening phase. External horizontal, rather than isostatic vertical forces are required for inversion because many deep sediment-filled basins around the world have never been inverted, but should have been, if isostatic rebound were the driving mechanism.
Inversion can range in scale from basins to sub-basins to selected structures within basins. Typically, rift basins can be later inverted. Mainly by reactivation of older normal faults, inversion selects rift basins where, in pure shear, weakening because of necking or thinning of lithosphere has occurred; and where, in simple shear, mechanical detachment surfaces are available for subsequent movement. Some pre-existing lows or sags can apparently be inverted in the absence of reactivated normal faults, as in the southern Altiplano of Bolivia and offshore Sabah, Borneo.
Basins can be inverted by dominantly strike-slip with some convergent component, e.g. offshore northeast Brazil, and by almost direct compression, Atlas Mountains, Morocco. A prime difference is that convergent strike-slip can reactivate relatively high-angle normal faults as reverse faults, whereas these faults tend to lock when subjected to more direct compression which then creates lower angle contractional faults. Usually, inversion is caused by a combination of compression and strike-slip (transpression) because the azimuth of maximum principal compressional stress to the direction of original basin trend vectors into an oblique-slip component. This is illustrated in northern Argentina where compression derived from Andean deformation is resolved obliquely (about 45°) against an older rift basin in the foreland nearby. Interestingly, for this area at least, the 45° angle which affords an equal contribution of strike slip and compression results only in reactivation of older normal faults and does not create younger contractional features.
Apparently compressive forces can be transmitted backward from the lead edge of an underthrusted foreland plate to invert rather remote regions and basins that are carried on that plate; this may be a significant part of the mechanism for basin inversion in northwest Europe and the southern North Sea as that foreland region underthrusted along the Alpine system.
Fold belt in the San Jorge Basin, Argentina: an example of tectonic inversion
Authors: Homovc J. F. , Conforto G. A. , Lafourcade P. A. , Chelotti L. A. 
Published: April 2008

Abstract
The San Jorge basin, located in southern Argentina, extends over the central part of the Patagonian region. The sedimentary fill of the basin is related to different rift and sag tectonic phases, from Triassic to Cretaceous. During Late Cretaceous-Early Tertiary, a marine transgression from the Atlantic developed; Tertiary sediments completed the basin fill. Late Tertiary compression produced a narrow structural belt that crops out in the San Bernardo Range and is present in the subsurface of the Santa Cruz and Chubut Provinces. The fold belt is 150 km long and 50 km wide. In its northern zone, it is formed by a series of anticlinal structures related to high angle reverse faults; in the southern part, these structures have similar characteristics, being associated with reverse faults which are the result of the reactivation of pre-existing normal faults. This report describes the structural features of a wide subsurface area of the fold belt, with high hydrocarbon potential. The development of the Neocomian sequence is used to establish the relationship between tectonism and sedimentation.
Transpressional inversion due to episodic rotation of extensional stresses in Jeanne d’Arc Basin, offshore Newfoundland
Authors: Sinclair Iain K. 
Published: April 2008

Abstract
Variations in structural architecture indicate that a ninety degree rotation of extensional stresses occurred between multiple Mesozoic rift phases, resulting in local structural inversion in the Jeanne d’Arc Basin on the Grand Banks of Newfoundland, offshore eastern Canada.
NW-SE-orientated extension caused dip-slip movement on NE-SW-trending en echelon faults during the Late Triassic to earliest Jurassic rift episode. These en echelon faults appear to have been separated by tilted basement relay ramps in accommodation zones rather than by cross-strike transfer faults.
NE-SW-orientated extension during the mid-Aptian to late Albian rift episode resulted in oblique-slip reactivation and linkage of the earlier normal faults. Transpressional stresses were generated by oblique-slip motion at restraining bends in Jeanne d’Arc Basin faults. Structural responses include: ‘pop-up’ blocks between upward-diverging faults; reverse faults separating overlapping ‘shingles’ of strata; forced folds in strata overlying deep-seated faults; and wrench-related folds trending oblique to through-going transfer fault zones. Salt and shale layers are seen to act as horizons of fault detachment, modifying the transmission of tectonic stress and strain from the basement into the sedimentary cover. The transpressional mechanism and direction of strike-slip motion are confirmed through recognition of associated transtensional structures located along fault strike at nearby releasing bends.
Transpressional structures in the Jeanne d’Arc Basin are recognizable over a wide range of scales from relatively large-scale reverse faults visible on seismic data to small-scale reverse faults seen in core.
Late Jurassic-Early Cretaceous inversion of the northern East Shetland Basin, northern North Sea
Authors: Thomas D. W. , Coward M. P. 
Published: April 2008

Abstract
Current research into the structural evolution of the East Shetland Basin, northern North Sea, indicates that a significant phase of structural inversion occurred during the Latest Jurassic-Early Cretaceous.
Structural effects of this tectonic phase include the pronounced uplift of pre- and syn-rift sequences along the western margin of the basin and the partial inversion of Mesozoic half-graben along intra-basinal NE-SW controlling faults. In addition, the localized occurrence of flower geometries and pop-ups along NE-SW trending faults suggests a component of strike-slip during the reactivation of these pre-existing structures.
Work presented stresses the importance in the role of pre-existing lineaments and the effects of superimposing subsequent non-coaxial extensional events upon them. Lineaments may be prominent reactivated basement shear zones or fault systems from earlier extensional phases.
Inversion will be analysed in detail with respect to two areas within the northern East Shetland Basin, the Tern sub-basin and the northern Penguin ridge. A regional tectonic model of northern North Sea rift evolution is presented and its implications to observed Latest Jurassic-Early Cretaceous structure discussed.
Inversion of a Lower Cretaceous extensional basin, south central Pyrenees, Spain
Authors: Bond R. M. G. , McClay K. R. 
Published: April 2008

Abstract
The structure of the Boixols thrust sheet is dominated by kilometric-scale E-W trending folds, the most important of which is the Sant Corneli-Boixols-Nargo fault-propagation, growth anticline at the leading edge of the thrust sheet. Five megasequences have been identified within the Boixols thrust sheet and these may be related to phases of extension, tectonic quiescence and phases of inversion. The Boixols thrust sheet incorporates the Lower Cretaceous Organyá basin which is bounded by a north-dipping extensional fault that underwent inversion in the Late Campanian-Maastrichtian and was incorporated into the Pyrenean south-vergent thrust system during the Eocene-Oligocene. The inversion history is recorded by the syn-inversion Arén growth sequence that is only preserved in the footwall syncline of the main fault-propagation growth fold. During inversion a short-cut thrust fault developed in the footwall to the Lower Cretaceous extensional fault. This now forms the Boixols thrust at surface. An inversion model for the Boixols thrust sheet and the Organyá basin is proposed and compared to analogue and numerical models of half-graben inversion. This model for inversion in the Boixols thrust sheet may be applied to other thrust structures in the Pyrenees and to other foreland fold and thrust belts.
Structural development and stratigraphy of the Kyokpo Pull-Apart Basin, South Korea and tectonic implications for inverted extensional basins
Authors: Lambiase Joseph. J. , Bosworth William P. 
Published: April 2008

Abstract
Field studies indicate that the Kyokpo Basin initially formed as a pull-apart during the Late Cretaceous Period. Syn-sedimentary normal and strike-slip faults suggest early transtensional movements. Fault-plane analysis indicates an approximately E-W extension direction for this early event. The basin filled with a succession of lacustrine deposits interbedded with abundant pyroclastic rocks and rare volcanic flows. Rapid initial subsidence is demonstrated by deep-water sediments that lie directly on pre-Late Cretaceous rocks. All exposed sedimentary facies were deposited in deep-water environments, indicating continued rapid subsidence during deposition of the entire sequence.
Laminated grey siltstones interbedded with thin, distal, sandy turbidites are the most abundant sediments. Channels filled with conglomeratic debris flow deposits (clasts as large as 1 m in diameter) cut into the siltstone beds. Massive and graded pebbly sandstone turbidites are also interbedded with siltstone. A thick accumulation of stacked, conglomeratic, debris flow deposits interbedded with sandstone turbidites forms a subaqueous fan complex at the southern part of the outcrop area.
Local compression caused up to 3 km of uplift and erosion following deposition of the Kyokpo strata. Thrust faults and small- and large-scale folds were formed by the W-E directed compression. Timing of the compression cannot be determined but probably correlates with a regional late Miocene transpressional event.
Inversion around the Bass Basin, SE Australia
Authors: Hill Kevin C. , Hill Kathy A. , Cooper Gareth T. , O’Sullivan Andrea J. , O’Sullivan Paul B. , Richardson M. Jane 
Published: April 2008

Abstract
Regional seismic reflection and fission track thermochronological studies of the Bass Basin area illustrate two types of inversion, both confined to the Bass failed rift. The first type involved 1–2 km of uplift, denudation and cooling of basement over more than 200 km along both margins of a failed rift, with lesser erosion within the rift basin. This occurred during renewed extension that bypassed the Bass Basin area leaving it as a failed rift. The uplift resulted from breaking of the lithosphere and may have been due, in part, to rebound following several kilometres of rapid sediment loading in the preceding 20 Ma. The second type comprised repeated structural inversion involving 1–3 km of uplift by compressional reactivation of extensional faults and along new reverse faults. These inversions occurred along the zone of maximum extension in a failed Mesozoic rift, such that Tasmania acted as a buttress to compression. The rifting and structural inversions are interpreted to have been controlled by a long-lived zone of weakness, perhaps overlying a Palaeozoic greenstone belt, with the maximum principal stress being roughly perpendicular to faults within the zone during inversion. Significantly, Miocene-Pliocene inversion resulted from the Australian craton being placed into compression following arc collision 3500 km to the north, emphasizing the importance of long distance transmission of compressional stresses through the lithosphere.
Development of structurally inverted basins: a case study from the West Coast, South Island, New Zealand
Authors: Bishop Daniel J. , Buchanan Peter G. 
Published: April 2008

Abstract

Cretaceous-Palaeogene basins in the West Coast of South Island, New Zealand, underwent inversion during the Neogene. Initial extension was oriented WNW-ESE and had a typical magnitude of
c.
5%, whilst subsequent shortening in the same direction was typically
c.
3–4%. This deformation produced a NNE-SSW trending basin and range province. Shortening was commonly partitioned into narrow zones along basin and range margins, leaving unreactivated extensional structures inbetween. Such margins are characterized by subparallel and en echelon Cretaceous — Palaeogene faults, which have been reactivated as predominantly reverse faults during the Neogene. Reverse faults propagated into the syn-inversion sedimentary sequence with increasingly shallow dip. Inversion caused local erosion of the original rift deposits. New back-thrusts, low-angle thrusts and folds developed during the late Neogene. Locally, incompetent Eocene mudstones deformed in a quasi-plastic manner, so that reverse faults at deeper structural levels became decoupled from thrust faults at shallower levels. Computer-aided section restoration has allowed validation of the interpretations, provided estimates of the timing and magnitude of deformation, and given a better understanding of the sequential development of inversion structures. Natural inversion structures show both contrasts and similarities to those produced in sand-box experiments.
Subdivision and correlation of monotonous sandstone sequences using high-resolution heavy mineral analysis, a case study: the Triassic of the Central Graben
Authors: Mange-Rajetzky Maria A. 
Published: April 2008

Abstract
The subdivision and correlation of monotonous siliciclastic sequences with poor biostratigraphic control and few lithostratigraphic markers has long been a problem. The need to find an efficient approach is even greater for subsurface sequences where information from cores and wireline logs has proved inadequate. In this short paper a novel approach, high-resolution heavy minerals analysis (HRHMA), is introduced, which is particularly suitable for the subdivision of problematical clastic sediments where other techniques are inconclusive. A full paper, which will present the technique in more detail, will be published shortly.
Clay mineral stratigraphy in Palaeozoic and Mesozoic red bed facies onshore and offshore UK
Authors: Jeans C. V. 
Published: April 2008

Abstract
Different methods of clay mineral correlation within sedimentary sequences provide varying degrees of stratigraphical resolution. These range from: (1) precise time correlation by the recognition of clay-forming events; (2) levels of general stratigraphical significance based upon changes in clay mineral assemblages reflecting widespread climatic, topographic or sea-level changes; (3) correlations of no stratigraphical significance where the distribution of clay minerals reflect patterns of detrital dispersal, pore-fluid flow in buried sediments, or metamorphism. The main use of clay mineral stratigraphy is to provide an alternative means of correlating effectively unfossiliferous sediments by tying them into biostratigraphically dated standard sequences in which the clay mineral variations are well established. Since 1980 it has been used in offshore UK to help correlation in the Old Red Sandstone (Devonian-Lower Carboniferous) of the North Sea and west of Shetland, and the New Red Sandstone (late Carboniferous-Triassic) of the Southwest Approaches, southern North Sea Basin and the central North Sea. Results of these studies are described and critically assessed.
Luminescence dating of Quaternary sediments
Authors: Rendell H. M. 
Published: April 2008

Abstract
Luminescence techniques have the potential to date Quaternary sediments from a range of depositional environments. Recent developments of optical dating complement thermoluminesscence dating techniques, extending their applicability. The age range of samples that can be dated shows a strong dependence on the material involved. Recent work on both dune sands and loess indicates that accurate dating to beyond 500 ka may be possible in certain circumstances. The age range limits for other material may be closer to 100 ka. Examples are given of luminescence dating of material from a range of sedimentary environments.
Sequence stratigraphic response to Aptian-Albian rifting in conjugate margin basins: a comparison of the Jeanne d’Arc Basin, offshore Newfoundland, and the Porcupine Basin, offshore Ireland
Authors: Sinclair Iain K. 
Published: April 2008

Abstract
Analysis of well and seismic data indicates that both the Jeanne d’Arc Basin on the Grand Banks of Newfoundland and the Porcupine Basin on the continental shelf off western Ireland were undergoing extension characterized by subsidence and rotation of fault blocks during mid-Aptian to late Albian times. Stratigraphic sequences in these conjugate basins developed in response to synchronous rift tectonism.
The base of each syn-rift sequence is defined by an angular unconformity which formed in response to regional uplift. This mid-Aptian rift-onset unconformity is buried beneath a depositional sequence characterized by retrogradational coastal sediments overlain by progradational coastal sediments in each basin. However, the lower retrogradational deposits dominate the syn-rift sequence in the Jeanne d’Arc Basin, while the upper progradational deposits dominate the syn-rift sequence in the northern Porcupine Basin. The relative dominance of sediments deposited along either transgressive or regressive coastlines was mainly determined by the local interplay of variable rates of rift-induced subsidence and sediment input.
The initiation of seafloor spreading between the Flemish Cap/Orphan Knoll and Goban Spur/Porcupine Bank continental margins near the end of Albian time resulted in the establishment of regional thermal subsidence, rapid coastal transgression and fully marine deposition above a locally-developed sequence-bounding unconformity.
Seismic investigation of the Faeroe basalts and their substratum
Authors: Kiørboe Liselotte , Petersen Steen Agerlin 
Published: April 2008

Abstract
Various seismic techniques have been used to investigate the subsurface in the area around the 2.2 km deep Lopra-1 well located on the Faeroe Islands. The techniques include vertical seismic profiling, walk-away vertical seismic profiling and refraction seismic profiling. Integration of these three different techniques, using a combined profiling method, makes it possible to overcome some of the problems arising from the large acoustic impedance contrasts and S-wave scattering which often exist in volcanic areas.
The three seismic profiles show distinct compressional (P) and shear (S) energy arrivals. The direct S-wave is generated at basalt interfaces at or just below the sea bed and interferes in part with groundroll in the refraction recordings. The low noise activity before first arrival indicates the very high quality of the VSP data. The VSP and the walk-away VSP recordings show clear evidence of reflected P-waves, while reflected P-waves are more difficult to recognize on the surface recordings.
The velocity through the basalt flows is shown to be dependent on the thickness of the basalt beds. Thick beds yield high velocities, while thin beds generate lower velocities. Velocity anisotropy is observed in the upper 700 m, probably resulting from cracks in the columnar basalt flows or from master joints.

The seismic examination of the three profiles shows excellent interbasaltic reflections. A very strong reflector with a negative reflection coefficient is observed at a depth of
c.
2.35 km and is interpreted to be the base of the basalt flows. Deeper reflections are interpreted as sills in the substratum of the basalt flows.
Seismic stratigraphy of the Bill Bailey and Lousy Bank area: implications for subsidence history
Authors: Vanneste K. , Henriet J.-P. , Posewang J. , Theilen F. 
Published: April 2008

Abstract
The present study discusses some results of a reconnaissance seismic survey carried out in 1988 in the area around the prominent Bill Bailey and Lousy Banks, located SW of the Faeroe Islands. The area is thought to be part of the Rockall-Faeroe microcontinent, which was flooded by Palaeocene plateau basalts. The seafloor topography is largely due to the present-day organization of the basalt surface. Important structural features exhibited by this basement are sub-surface diverging reflectors and a major fault.
Sediment accumulation is confined to the basinal area where four unconformities were identified. The lower boundary corresponds to the well-known reflector R4 of the North Atlantic. The other unconformities are proposed to correlate with hiatuses at the beginning and end of the middle Miocene, and at the end of the Pliocene, respectively. The sediment units are briefly described by their upper and lower boundary, seismic facies and thickness variations. About the lithology, however, little is so far known. The sediments are deformed by intraformational faults and a diapir-like structure. Both deformational styles are probably related to temporary overpressurisation in fine-grained sediments, but resulting from different causes.
Stratal geometric patterns indicate that initially the subsidence of the basalt surface was rather uniform, but became non-uniform after the Eocene/Oligocene boundary, differentiating the two banks from the surrounding basin.
The relationship between the distribution of Tertiary sediments, tectonic processes and deep-water circulation around the Faeroe Islands
Authors: Boldreel Lars Ole , Andersen Morten Sparre 
Published: April 2008

Abstract
Compressional structures, which were initiated in the Eocene, and thermal subsidence played an important role in the distribution of the post-Palaeocene sediments around the Faeroe Islands. Additionally, the deep-water currents passing through the Faeroe-Shetland Channel and the Faeroe Bank Channel contributed to the distribution of the sediments from Oligocene-Miocene to Recent. The relationship is illustrated by the outcrop of four pre-Upper Pliocene sedimentary sequences below a thin cover of Pleistocene sediments and the surface of the upper Palaeocene basalts in the study area, which consists of three basins — the Norwegian Sea, the Faeroe-Shetland Channel and the Faeroe Bank Channel, separated by compressional ridges. The axial part of the Faeroe-Shetland Channel is characterized by a fairly flat bottom topography caused by differential sedimentation and erosion by deep-water currents flowing against the topography. The flat channel floor narrows southwards to the tip of the Munkagrunnur Ridge. Due to tectonic structure, differential deposition and erosion, progressively older sediment units are exposed to the south. The channel floor stays narrow in the Faeroe Bank Channel. To the west of the Faeroe Channel Knoll, which is located within the central part of the deep Arctic bottom current, up to 2000 m of sediments are present. At the northern end of the Faeroe Bank Channel the basalt crops out as a result of non-deposition and erosion by the deep Arctic bottom current.