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Structural geology in reservoir characterization (1998)

Coward, M. P. [Hrsg.]

London : The Geological Society

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Call number: 9/M 99.0234

In: Geological Society special publication

Description / Table of Contents: The two main aims of this Special Publication are to capture the wide range of rapidly expanding research in this area, which reflects the increasing importance of comprehensive ‘structural characterization’ in static reservoir descriptions, and to help promote synergy between the geosciences and petroleum engineering disciplines. The first aim is addressed by the sixteen papers of the volume, the majority of which cover a range of structural geological features, particularly faulted and fractured reservoirs, fault gouge properties, fault seal potential and fluid flow/simulation modelling in faulted and fractured reservoirs. The papers draw heavily on experience obtained in the North Sea. This volume is for geologists, geophysicists and reservoir simulation/petroleum engineers studying faulted and fractured reservoirs, particularly those interested in studying petroleum traps, predicting fluid flow or modelling structurally heterogeneous reservoirs.

Type of Medium: Monograph available for loan

Pages: VIII, 266 S. , Ill., graph. Darst.

ISBN: 1897799942

Series Statement: Geological Society special publication 127

URL: http://sp.lyellcollection.org/content/127/1

Classification:

Deposits

Note: J. W. Cosgrove: The role of structural geology in reservoir characterization / Geological Society, London, Special Publications, 127:1-13, doi:10.1144/GSL.SP.1998.127.01.01 --- John Archer: Reservoir characterization and modelling: a framework for field development / Geological Society, London, Special Publications, 127:15-18, doi:10.1144/GSL.SP.1998.127.01.02 --- B. Freeman, G. Yielding, D. T. Needham, and M. E. Badley: Fault seal prediction: the gouge ratio method / Geological Society, London, Special Publications, 127:19-25, doi:10.1144/GSL.SP.1998.127.01.03 --- B. R. Crawford: Experimental fault sealing: shear band permeability dependency on cataclastic fault gouge characteristics / Geological Society, London, Special Publications, 127:27-47, doi:10.1144/GSL.SP.1998.127.01.04 --- Roy H. Gabrielsen, Randi-Kristin Aarland, and Einar Alsaker: Identification and spatial distribution of fractures in porous, siliciclastic sediments / Geological Society, London, Special Publications, 127:49-64, doi:10.1144/GSL.SP.1998.127.01.05 --- T. Manzocchi, P. S. Ringrose, and J. R. Underhill: Flow through fault systems in high-porosity sandstones / Geological Society, London, Special Publications, 127:65-82, doi:10.1144/GSL.SP.1998.127.01.06 --- Richard G. Gibson: Physical character and fluid-flow properties of sandstone-derived fault zones / Geological Society, London, Special Publications, 127:83-97, doi:10.1144/GSL.SP.1998.127.01.07 --- J. J. Walsh, J. Watterson, A. Heath, P. A. Gillespie, and C. Childs: Assessment of the effects of sub-seismic faults on bulk permeabilities of reservoir sequences / Geological Society, London, Special Publications, 127:99-114, doi:10.1144/GSL.SP.1998.127.01.08 --- Roderick J. Owen, Xiang-Yang Li, Colin D. Macbeth, and David C. Booth: Reservoir characterization: how can anisotropy help? / Geological Society, London, Special Publications, 127:115-119, doi:10.1144/GSL.SP.1998.127.01.09 --- L. Foley, T. S. Daltaban, and J. T. Wang: Numerical simulation of fluid flow in complex faulted regions / Geological Society, London, Special Publications, 127:121-132, doi:10.1144/GSL.SP.1998.127.01.10 --- S. A. Stewart and R. Podolski: Curvature analysis of gridded geological surfaces / Geological Society, London, Special Publications, 127:133-147, doi:10.1144/GSL.SP.1998.127.01.11 --- Gary D. Couples, Helen Lewis, and P. W. Geoff Tanner: Strain partitioning during flexural-slip folding / Geological Society, London, Special Publications, 127:149-165, doi:10.1144/GSL.SP.1998.127.01.12 --- Amgad I. Younes, Terry Engelder, and William Bosworth: Fracture distribution in faulted basement blocks: Gulf of Suez, Egypt / Geological Society, London, Special Publications, 127:167-190, doi:10.1144/GSL.SP.1998.127.01.13 --- Lidia Lonergan, Joe Cartwright, Rod Laver, and Joe Staffurth: Polygonal faulting in the Tertiary of the central North Sea: implications for reservoir geology / Geological Society, London, Special Publications, 127:191-207, doi:10.1144/GSL.SP.1998.127.01.14 --- R. K. Aarland and J. Skjerven: Fault and fracture characteristics of a major fault zone in the northern North Sea: analysis of 3D seismic and oriented cores in the Brage Field (Block 31/4) / Geological Society, London, Special Publications, 127:209-229, doi:10.1144/GSL.SP.1998.127.01.15 --- Haakon Fossen and Jonny Hesthammer: Structural geology of the Gullfaks Field, northern North Sea / Geological Society, London, Special Publications, 127:231-261, doi:10.1144/GSL.SP.1998.127.01.16

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Early precambrian processes (1995)

Coward, M. P. [Hrsg.]

London : The Geological Society

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Call number: 9/M 96.0442

In: Geological Society special publication

Description / Table of Contents: This volume contains a selection of 16 papers written by colleagues and students of the late Professor John Sutton FRS. John Sutton was one of the most eminent geologists of his time. He was interested in every aspect of the Earth Sciences, although his passion was for Precambrian rocks throughout the world, and particularly those of NW Scotland. The papers included in this volume reflect the wide interests of John Sutton and provide the latest ideas and information on the Early Precambrian.

Type of Medium: Monograph available for loan

Pages: VIII, 295 S. , Ill., zahlr. graph. Darst. und Kt.

ISBN: 1897799365

Series Statement: Geological Society special publication 95

URL: http://sp.lyellcollection.org/content/95/1

Classification:

Historical Geology

Language: English

Note: Maarten J. De Wit and Andrew Hynes: The onset of interaction between the hydrosphere and oceanic crust, and the origin of the first continental lithosphere / Geological Society, London, Special Publications, 95:1-9, doi:10.1144/GSL.SP.1995.095.01.01 --- Kenneth A. Eriksson: Crustal growth, surface processes, and atmospheric evolution on the early Earth / Geological Society, London, Special Publications, 95:11-25, doi:10.1144/GSL.SP.1995.095.01.02 --- E. G. Nisbet: Archaean ecology: a review of evidence for the early development of bacterial biomes, and speculations on the development of a global-scale biosphere / Geological Society, London, Special Publications, 95:27-51, doi:10.1144/GSL.SP.1995.095.01.03 --- R. M. Shackleton: Tectonic evolution of greenstone belts / Geological Society, London, Special Publications, 95:53-65, doi:10.1144/GSL.SP.1995.095.01.04 --- P. Choukroune, H. Bouhallier, and N. T. Arndt: Soft lithosphere during periods of Archaean crustal growth or crustal reworking / Geological Society, London, Special Publications, 95:67-86, doi:10.1144/GSL.SP.1995.095.01.05 --- Peter J. Treloar and Tom G. Blenkinsop: Archaean deformation patterns in Zimbabwe: true indicators of Tibetan-style crustal extrusion or not? / Geological Society, London, Special Publications, 95:87-107, doi:10.1144/GSL.SP.1995.095.01.06 --- James F. Wilson, Robert W. Nesbitt, and C. Mark Fanning: Zircon geochronology of Archaean felsic sequences in the Zimbabwe craton: a revision of greenstone stratigraphy and a model for crustal growth / Geological Society, London, Special Publications, 95:109-126, doi:10.1144/GSL.SP.1995.095.01.07 --- Alec F. Trendall: Paradigms for the Pilbara / Geological Society, London, Special Publications, 95:127-142, doi:10.1144/GSL.SP.1995.095.01.08 --- John S. Myers: The generation and assembly of an Archaean supercontinent: evidence from the Yilgarn craton, Western Australia / Geological Society, London, Special Publications, 95:143-154, doi:10.1144/GSL.SP.1995.095.01.09 --- D. I. Groves, J. R. Ridley, E. M. J. Bloem, M. Gebre-Mariam, S. G. Hagemann, J. M. A. Hronsky, J. T. Knight, N. J. McNaughton, J. Ojala, R. M. Vielreicher, T. C. McCuaig, and P. W. Holyland: Lode-gold deposits of the Yilgarn block: products of Late Archaean crustal-scale overpressured hydrothermal systems / Geological Society, London, Special Publications, 95:155-172, doi:10.1144/GSL.SP.1995.095.01.10 --- R. J. Herrington: Late Archaean structure and gold mineralization in the Kadoma region of the Midlands greenstone belt, Zimbabwe / Geological Society, London, Special Publications, 95:173-191, doi:10.1144/GSL.SP.1995.095.01.11 --- David Bridgwater, Flemming Mengel, Brian Fryer, Paul Wagner, and Søren Claudius Hansen: Early Proterozoic mafic dykes in the North Atlantic and Baltic cratons: field setting and chemistry of distinctive dyke swarms / Geological Society, London, Special Publications, 95:193-210, doi:10.1144/GSL.SP.1995.095.01.12 --- R. G. Park: Palaeoproterozoic Laurentia-Baltica relationships: a view from the Lewisian / Geological Society, London, Special Publications, 95:211-224, doi:10.1144/GSL.SP.1995.095.01.13 --- Timothy James Wynn: Deformation in the mid to lower continental crust: analogues from Proterozoic shear zones in NW Scotland / Geological Society, London, Special Publications, 95:225-241, doi:10.1144/GSL.SP.1995.095.01.14 --- Mike P. Coward, Richard M. Spencer, and Camille E. Spencer: Development of the Witwatersrand Basin, South Africa / Geological Society, London, Special Publications, 95:243-269, doi:10.1144/GSL.SP.1995.095.01.15 --- R. H. Graham: Asian analogues for Precambrian tectonics? / Geological Society, London, Special Publications, 95:271-289, doi:10.1144/GSL.SP.1995.095.01.16

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Deformation, metamorphism and imbrication of the Indian plate, south of the Main Mantle Thrust, north Pakistan (1989)

TRELOAR, P. J. ; BROUGHTON, R. D. ; WILLIAMS, M. P. ; [et al.]

Oxford, UK : Blackwell Publishing Ltd

Journal of metamorphic geology 7 (1989), S. 0

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ISSN: 1525-1314

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Geosciences

Notes: South of the Main Mantle Thrust in north Pakistan, rocks of the northern edge of the Indian plate were deformed and metamorphosed during the main southward thrusting phase of the Himalayan orogeny. In the Hazara region, between the Indus and Kaghan Valleys, metamorphic grade increases northwards from chlorite zone to sillimanite zone rocks in a typically Barrovian sequence. Metamorphism was largely synchronous with early phases of the deformation. The metamorphic rocks were subsequently imbricated by late north-dipping thrusts, each with higher grade rocks in the hanging wall than in the footwall, such that the metamorphic profile shows an overall tectonic inversion. The rocks of the Hazara region form one of a number of internally imbricated metamorphic blocks stacked, after the metamorphic peak, on top of each other during the late thrusting. This imbrication and stacking represents an early period of post-Himalayan uplift.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1525-1314.1989.tb00578.x

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The Okahandja Lineament and its significance for Damaran tectonics in Namibia (1981)

Downing, Kevin N. ; Coward, M. P.

Springer

International journal of earth sciences 70 (1981), S. 972-1000

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ISSN: 1437-3262

Source: Springer Online Journal Archives 1860-2000

Topics: Geosciences

Description / Table of Contents: Abstract The Okahandja Lineament is considered to represent the southern margin of a magmatic arc produced by the northerly subduction of the Damran Ocean between 750 and 520 Ma ago. Sediments of the Orogen and granitoid intrusives produced by subduction and crustal melting, underwent shear deformation between 675 and 575 Ma in a low angle zone of sinistral sense shear. The Okahandja Lineament represents a zone of differential movement between the Central and Southern Zones of the Orogen during this simple shear deformation. Both overriding and overriden plates were deformed at about 550 and 520 Ma. Production of open S.E. verging structures on the northern plate was accompanied by more intense thrust and fold nappe production on the southern margin of the Damaran Orogen. During this last deformation event, the Central magmatic Zone was downfolded under the southern zone. This fold is the present expression of the Okahandja Lineament. Two tectonic models are proposed for the structures identified within the Central and Southern Zones of the Orogen, combined with evidence from the northern coastal arm of the Orogen.

Abstract: Résumé Le linéament de Okahandja est considéré comme la marge bordant au sud un «arc magmatique» résultant de la subduction vers le nord de l'Océan damaranique durant l'intervalle 750-520 M. a. - Les sédiments de l'orogène et les intrusions granitoÏdes produites par la subduction et par la fusion de la croûte subirent, entre 675 et 575 M. a., de nobreuses déformations cisaillantes, sénestres, le long d'une zone faiblement inclinée. Le linéament de Okahandja représente, pour les déformations cisaillantes simples une zone de déplacements partiels entre la zone centrale et la zone méridionale de l'orogène. Les deux plaques, celle du toit et celle du mur, de ce chevauchement furent déformées entre approximativement 550 et 520 M. a. Ces structures ouvertes, déversées vers le nord, se formèrent dans la plaque septentrionale, pendant que des nappes en plis naissaient simultanément, sous l'influence d'une forte so sollicitation, dans la marge méridionale de l'orogène damaranique, ce qui entraÎna le ploiement de la zone magmatique centrale sous la zone méridionale. Ce pli est la forme sous laquelle apparaÎt aujourd'hui le linéament de Okahandja. Deux modèles tectoniques sont proposés pour expliqeur les structures ainsi reconnues dans les zones centrale et méridionale de l'orogène, sur la base du fait d'un bras le long de la cÔte septentrionale de l'orogène.

Notes: Zusammenfassung Das Okahandja-Lineament wird als der Südrand eines „magmatischen Bogens“ (Wurzelzone eines Inselbogens) verstanden, der auf die nordwÄrts gerichtete Subduktion des Damara Ozeans von 750 bis 520 Ma zurückgeführt wird. Die Sedimente des Orogens und die granitoiden Intrusiva, die durch Subduktion und daraus folgender Aufschmelzung der Kruste entstanden, erlitten mehrfache linksgerichtete Scherdeformation entlang einer flachliegenden Zone zwischen 675 und 575 Ma. Das Okahandja-Lineament stellt eine Zone von Teilbewegungen dar für die einfachen Scherdeformationen zwischen der zentralen und der südlichen Zone des Orogens. Die hangende und die liegende Platte wurden zwischen ca. 550 und 520 Ma deformiert. In der nördlichen Platte wurden offene SE-vergente Strukturen gebildet, wÄhrend gleichzeitig am südlichen Rand des Damara-Orogens durch die grö\ere Beanspruchung Falten-Decken entstanden. Dabei wurde die zentrale magmatische Zone unter die südliche Zone gebogen. Diese Falte ist das heutige Erscheinungsbild des Okahandja Lineaments. Zwei tektonische Modelle werden dargelegt, um die erkannten Strukturen in der zentralen und südlichen Zone des Orogens unter Verwendung der Evidenz vom nördlichen Küstenarm des Orogens zu erklÄren.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF01820175

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Preliminary conclusions of the Royal Society and Academia Sinica 1985 geotraverse of Tibet (1986)

Chengfa, Chang ; Nansheng, Chen ; Coward, M. P. ; [et al.]

[s.l.] : Nature Publishing Group

Nature 323 (1986), S. 501-507

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ISSN: 1476-4687

Source: Nature Archives 1869 - 2009

Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics

Notes: [Auszug] The 1985 Chinese/British expedition to the Tibetan Plateau attempted to solve the question of the origin of the very thick crustal rocks in this region. Continuing northwards movement of the Indian plate over the past 38 Myr has given rise to severe folding and thrust faulting, causing crustal ...

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1038/323501a0

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Structural evolution of a crustal section in the western Himalaya (1982)

Coward, M. P. ; Jan, M. Q. ; Rex, D. ; [et al.]

[s.l.] : Nature Publishing Group

Nature 295 (1982), S. 22-24

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ISSN: 1476-4687

Source: Nature Archives 1869 - 2009

Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics

Notes: [Auszug] Recent field work on the Kohistan complex in the Karakorum Range of North Pakistan has shown its stratigraphy to be repeated by several phases of tight to isoclinal folding. This reveals a close association between igneous activity and a late deformation and complicates the previously proposed ...

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1038/295022a0

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Large scale Palaeozoic shear zone in Australia and present extension to the Antarctic Ridge (1976)

COWARD, M. P.

[s.l.] : Nature Publishing Group

Nature 259 (1976), S. 648-649

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ISSN: 1476-4687

Source: Nature Archives 1869 - 2009

Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics

Notes: [Auszug] The sigmoidal curve in the trend of the Palaeozoic folds has the form of a ductile shear zone analogous to the small scale, ductile shear structures described from deformed igneous rocks1. This is confirmed by the parallelism of isogons drawn for the regional change in axial plane and cleavage ...

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1038/259648a0

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Dynamics of the Polish and Eastern Slovakian parts of the Carpathian accretionary wedge: insights from palaeostress analyses (2007)

Nemcok, M. ; Dilov, T. ; Wojtaszek, M. ; [et al.]

In: Geological Society Special Publication 272: 271-302.

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Publication Date: 2007-10-08

Description: The arcuate Outer Carpathian accretionary wedge formed in front of the East Alpine-Carpathian-Pannonian (ALCAPA) megablock during the Eocene-Sarmatian. The wedge accreted sediments of the subducting remnants of the Carpathian Flysch Basin, a large oceanic tract left in front of the Alpine orogen. The palaeostress data for the orogenic hinterland (particularly the data related to the Early Miocene extension that was expanding towards the NE), combined with coeval subduction-related volcanism that was expanding towards the NE, indicate that the uneven roll-back of the subduction zone was the main mechanism controlling the development of the northern West Carpathian arc. The palaeostress data for the Tertiary accretionary wedge from the same time period are characterized by outward-fanning {sigma}1 trajectories that changed gradually during the wedge development. In contrast, the palaeostress data for the hinterland are characterized by preferred-directional stress events that changed abruptly during the wedge development. These palaeostress results are in accordance with the behaviour of the wedge and the hinterland, as the wedge behaved as a weak continuum and the hinterland behaved as a block mosaic with weak boundaries. The fault traces of the northern West Carpathian arc converge to both ends of the arc and suggest that the pre-existing basin was the factor that controlled the arc location. These fault trace patterns are asymmetric, indicating a slightly oblique overall convergence in a NE-SW direction. In accordance with this convergence, the palaeostress data for the accretionary wedge indicate that the western part of the wedge, which is characterized by NW-SE-oriented maximum principal compressional stress {sigma}1, was undergoing sinistral transpression. Meanwhile, the eastern part, which is characterized by NE-SW-oriented {sigma}1, was undergoing compression. Apparently, the dynamics of the accretionary wedge was further influenced by the shape of an elongated NE-SW-trending ALCAPA megablock, which was located behind the wedge and advanced in the direction of the general Early Miocene convergence during the most pronounced stages of the wedge development. This megablock served as the local indenter, as its strength surpassed that of the accretionary wedge located to its front. Further dynamic complexities were added because of the complex shape of the Magura Unit, which was located in the most proximal portion of the wedge and was stronger than the units in front of it. Wedge outcrops indicate that the large-scale shortening, which is characterized by the development of detachments and ramps, was preceded by an initial layer-parallel shortening. This is indicated by scaly fabrics and minor reverse faults that rotated into locked positions during the later accretion. Several outcrops with a wedge detachment fault indicate that there was a relatively low amount of friction during its development. The decollement zone is several hundred metres thick and shows evidence of transient fluid flow that was driven by pressure gradients. This is documented by frequent hydrofracturing, sandstone dykes and fibrous veins that opened against the weight of the whole wedge, all of which indicate cycles of higher pore fluid pressures that lowered the basal friction.

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Tectonic development of North African basins (2003)

Coward, M. P. ; Ries, A. C.

In: Geological Society Special Publication 207: 61-83.

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Publication Date: 2003-01-01

Description: Mostly the Palaeozoic and Mesozoic basins of North Africa have generally followed, and reworked, earlier basement trends formed by: (1) the NW-SE accretion of continental and oceanic terranes onto a Pan-African nucleus in northeastern Africa, and (2) the collision of this amalgam of accretionary terranes with the West African Craton. During the Upper Precambrian Pan-African Orogeny, the West African Craton formed a rigid block which indented this amalgam of accreted mobile belts to form much of North Africa. Intrusion of this indentor into North Africa caused the expulsion of narrow, triangular-shaped blocks of lithosphere to the north and south in a tectonic style very similar to the Miocene-Pliocene deformation of Tibet. Expulsion reactivated the earlier shear zones to form an anastomosing pattern of steeply dipping shears with left and right lateral sense of displacement. Left lateral shear also affected the northern edge of the West African Craton during this process of indentation. Subsequent rifting of the Pan-African mountain belt resulted in a series of grabens, which were infilled with Upper Precambrian-Cambrian molasse. These are the precursor basins for the Palaeozoic sediments which cover much of North Africa. The effects of rifting continued into the Cambro-Ordovician in the western basins. During the Silurian-Devonian many of the rifts were reworked. A new basin formed in the Atlas and Anti-Atlas, related to the growth of the proto-Tethyan Ocean. Basin inversion characterizes the Palaeozoic structures of the western Atlas and Anti-Atlas, producing thickened crust and a large mountain belt during the Carboniferous. Foreland basins formed on either side of this mountain belt and both the mountains and the adjacent basins were compartmentalized by WNW--ESE-trending transfer zones. Pan-African structures, within the African Plate, were reworked with further indentation of the West African Craton into Pan-African crust. The craton was pushed eastward, generating a left lateral shear couple along its northern margin. NW--SE-trending faults were reworked as dominantly left lateral strike-slip faults and N--S-trending fault blocks were rotated slightly in a clockwise sense. There was probably further lateral expulsion of lithosphere, ahead of the NE--SW-trending front of the indentor, reworking earlier N--S-trending shear zones. The North African Palaeozoic basins were inverted during the Hercynian-Appalachian Orogeny. In the Ahnet Basin the shortening was approximately NNE-SSW, perpendicular to the trend of the structures. This inversion was particularly marked in the Ougarta-Ahnet Basin where it produced a series of open to closed, north-south to NW--SE-trending folds above reactivated basement faults. During the Mesozoic, the Hercynian-Appalachian mountain belt underwent extension to produce deep rift basins infilled with continental sediments and some volcanics. The High Atlas formed as an arm to the Atlantic Basin. Transfer zones have a WNW-ESE trend, indicating that this was the main extension direction, similar to that in western and southwestern Europe. In northeastern Algeria, the orientation of the Mesozoic grabens suggests reworking of the basement fabric formed by Pan-African accretionary tectonics. The structures appear to die out toward the southwest into a broad transfer zone with some NW--SE-trending faults. The northeastern edge of the basin is obscured by later rift basins in the eastern Mediterranean. The Palaeozoic faults of the Amguid Spur, overlying one of the major shear zones of the Hoggar, formed a structural high throughout the Mesozoic with probably several pulses of inversion. An important episode of inversion occurred during the Aptian-Albian with the development of anticlines and associated reverse faults. Crustal extension associated with block faulting occurred in the Sirte Basin of Libya during the Mid- and Late Cretaceous. The block faults trend NNW--SSE to NW--SE, cross-cutting earlier Palaeozoic fold structures at a high angle but possibly parallel to some of the basement shear zones. The faults form the tips of a rift basin which opened between Sicily and Tunisia in the central Mediterranean. The Cretaceous faults have a component of right lateral displacement as well as normal fault movements. The Mesozoic basins of the High and Middle Atlas were inverted during the Late Cretaceous-Early Oligocene. The displacement direction, as seen from the transfer systems, was NW--SE, almost perpendicular to the Middle Atlas, but at a lower angle with the High and Sahara Atlas, which must have had components of oblique or right lateral movement. Minor effects of this inversion are reported from the Saharan basins.

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