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34-599: The European Cenozoic Rift System ( ECRIS ) is a 1,100 km (680 mi) long system of rifts formed in the foreland of the Alps as the lithosphere responded to the effects of the Alpine and Pyrenean orogenies . The system began to form during the Late Eocene and parts (particularly the Upper and Lower Rhine Grabens ) remain seismically active today and are responsible for most of

68-449: A lacustrine environment or in a restricted marine environment, although not all rifts contain such sequences. Reservoir rocks may be developed in pre-rift, syn-rift and post-rift sequences. Effective regional seals may be present within the post-rift sequence if mudstones or evaporites are deposited. Just over half of estimated oil reserves are found associated with rifts containing marine syn-rift and post-rift sequences, just under

102-565: A "fixist". Part of Stille's work dealt with massifs and sedimentary basins in Central Europe; differing from Suess' interpretations for the same area showing that between the Bohemian and Rhine massifs Mesozoic rocks were folded . A central tenet in Stille's geology was that geosynclines became depressions without any faulting with any fault found being the product of later processes like

136-462: A high angle. These segment boundary zones accommodate the differences in fault displacement between the segments and are therefore known as accommodation zones. Accommodation zones take various forms, from a simple relay ramp at the overlap between two major faults of the same polarity, to zones of high structural complexity, particularly where the segments have opposite polarity. Accommodation zones may be located where older crustal structures intersect

170-403: A kind of orogeneses in extensional settings, which is referred as to rifting orogeny. Once rifting ceases, the mantle beneath the rift cools and this is accompanied by a broad area of post-rift subsidence. The amount of subsidence is directly related to the amount of thinning during the rifting phase calculated as the beta factor (initial crustal thickness divided by final crustal thickness), but

204-438: A mid-oceanic ridge and a set of conjugate margins separated by an oceanic basin. Rifting may be active, and controlled by mantle convection . It may also be passive, and driven by far-field tectonic forces that stretch the lithosphere. Margin architecture develops due to spatial and temporal relationships between extensional deformation phases. Margin segmentation eventually leads to the formation of rift domains with variations of

238-496: A quarter in rifts with a non-marine syn-rift and post-rift, and an eighth in non-marine syn-rift with a marine post-rift. Hans Stille Hans Wilhelm Stille (8 October 1876 – 26 December 1966) was an influential German geologist working primarily on tectonics and the collation of tectonic events during the Phanerozoic . Stille adhered to the contracting Earth hypothesis and together with Leopold Kober he worked on

272-402: Is also affected by the degree to which the rift basin is filled at each stage, due to the greater density of sediments in contrast to water. The simple 'McKenzie model' of rifting, which considers the rifting stage to be instantaneous, provides a good first order estimate of the amount of crustal thinning from observations of the amount of post-rift subsidence. This has generally been replaced by

306-757: Is filled with Cenozoic sediments up to 2 km thick. The Bresse Graben lies to the east of the Limagne Graben. Rifting started during the Eocene, pausing from the Late Oligocene to Middle Miocene before resuming in the Late Miocene. The eastern margin of the basin was overridden by thrust faults from the Jura Mountains , the leading edge of the Alpine thin-skinned deformation . The Upper Rhine Graben extends from

340-811: Is thinned, the Earth's surface subsides and the Moho becomes correspondingly raised. At the same time, the mantle lithosphere becomes thinned, causing a rise of the top of the asthenosphere. This brings high heat flow from the upwelling asthenosphere into the thinning lithosphere, heating the orogenic lithosphere for dehydration melting, typically causing extreme metamorphism at high thermal gradients of greater than 30 °C. The metamorphic products are high to ultrahigh temperature granulites and their associated migmatite and granites in collisional orogens, with possible emplacement of metamorphic core complexes in continental rift zones but oceanic core complexes in spreading ridges. This leads to

374-461: Is thought to be experiencing dextral strike-slip reactivation. The Lower Rhine Graben or Lower Rhine Embayment, trends NW-SE and continues offshore into structures within the southern North Sea . To the southeast the dominant faults are SW-dipping, while to the northwest they become NE-dipping, in both cases giving it a half-graben geometry. Rifting initiated during the Oligocene and continues to

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408-851: The Rhine Rift Valley and the Mainz Basin . Here the rift system splits up into a north-eastern and a north-western branch. Part of the north-western branch is the Lower Rhine Bay and the Lower Rhine Rift as a central Netherlands rift system. The north-eastern branch continues with the Wetterau , the Giessen Basin , the Amöneburg Basin , the Upper Hessian Ridge near Neustadt ,

442-749: The West Hesse Depression , the Leine Rift , part of the Salt dome region in northern Germany, the Kattegat , the Oslo Rift and eventually Mjøsa with Lillehammer at its northern end. In the area surrounding the Mediterranean-Mjosa Zone there was some volcanism, e.g. Kaiserstuhl or Hoher Habichtswald west of Kassel , which primarily consist of Basalt . Rift Major rifts occur along

476-423: The Moho topography, including proximal domain with fault-rotated crustal blocks, necking zone with thinning of crustal basement , distal domain with deep sag basins, ocean-continent transition and oceanic domain. Deformation and magmatism interact during rift evolution. Magma-rich and magma-poor rifted margins may be formed. Magma-rich margins include major volcanic features. Globally, volcanic margins represent

510-443: The geosyncline theory to explain orogeny . Stille's ideas emerged in the aftermath of Eduard Suess ' book Das Antlitz der Erde (1883–1909). Stille's and Kober's school of thought was one of two that emerged in the post-Suess era the other being headed by Alfred Wegener and Émile Argand . This competing view rejected Earth contraction and argued for continental drift . As Stille opposed continental drift he came to be labelled

544-645: The 'flexural cantilever model', which takes into account the geometry of the rift faults and the flexural isostasy of the upper part of the crust. Some rifts show a complex and prolonged history of rifting, with several distinct phases. The North Sea rift shows evidence of several separate rift phases from the Permian through to the Earliest Cretaceous , a period of over 100 million years. Rifting may lead to continental breakup and formation of oceanic basins. Successful rifting leads to seafloor spreading along

578-454: The Baikal Rift have segment lengths in excess of 80 km, while in areas of warmer thin lithosphere, segment lengths may be less than 30 km. Along the axis of the rift the position, and in some cases the polarity (the dip direction), of the main rift bounding fault changes from segment to segment. Segment boundaries often have a more complex structure and generally cross the rift axis at

612-422: The central axis of most mid-ocean ridges , where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates . Failed rifts are the result of continental rifting that failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot . Two of these evolve to

646-663: The collision along the Alps intensified and the western part of France moved to the west. The development of the ECRIS was accompanied (and in some cases preceded) by volcanic activity over large parts of the rift system that persisted into the Quaternary . The largest volcanic centres were located to the southwest of the Limagne and Bresse Grabens, the Massif Central , at the rift triple junction at

680-420: The final collapse of the geosyncline. In 1933 Stille would shorten Leopold Kober's concept of kratogen , that was used to describe those portions of the continental crust that were old and stable, into kraton (English: craton ). The Geotectonic Research journal was founded in 1937 by Hans Stille and Franz Lotze . The enormous influence that Stille's concepts had on tectonics is obvious from many of

714-402: The larger bounding faults. Subsequent extension becomes concentrated on these faults. The longer faults and wider fault spacing leads to more continuous areas of fault-related subsidence along the rift axis. Significant uplift of the rift shoulders develops at this stage, strongly influencing drainage and sedimentation in the rift basins. During the climax of lithospheric rifting, as the crust

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748-689: The larger earthquakes in Europe, north of the Alps. The ECRIS consists of a series of rifts and associated transfer faults extending from the Mediterranean to the North Sea . This north-south trending rift structure formed in the middle Eocene creating a lake that is now the Limagne plain. The main phase of subsidence continued until the Late Oligocene . The graben is controlled by faults on its western side and

782-567: The majority of passive continental margins. Magma-starved rifted margins are affected by large-scale faulting and crustal hyperextension. As a consequence, upper mantle peridotites and gabbros are commonly exposed and serpentinized along extensional detachments at the seafloor. Many rifts are the sites of at least minor magmatic activity , particularly in the early stages of rifting. Alkali basalts and bimodal volcanism are common products of rift-related magmatism. Recent studies indicate that post-collisional granites in collisional orogens are

816-614: The northern edge of the Jura mountains in the south up to the triple junction where the ECRIS branches. Rifting initiated here in the Oligocene but the northern and southern parts of the graben show distinct post-Oligocene histories. In the Miocene the southern part of the graben became uplifted, while the northern part continued to subside into the Pleistocene . Currently the Upper Rhine Graben

850-690: The northern end of the Upper Rhine Graben, the Vogelsberg Mountains and around the Eger Graben. The last recorded volcanic activity was a phreatomagmatic eruption in the Chaîne des Puys about 6,000 years ago. Most seismic activity within the ECRIS is confined to the Upper and Lower Rhine Grabens. The 1356 Basel earthquake , which had an epicenter within the Upper Rhine Graben is the most damaging historical seismic event known from central Europe. The term Mediterranean-Mjosa Zone (Mittelmeer-Mjösen-Zone)

884-411: The onset of rifting, the upper part of the lithosphere starts to extend on a series of initially unconnected normal faults , leading to the development of isolated basins. In subaerial rifts, for example, drainage at the onset of rifting is generally internal, with no element of through drainage. As the rift evolves, some of the individual fault segments grow, eventually becoming linked together to form

918-456: The point of seafloor spreading, while the third ultimately fails, becoming an aulacogen . Most rifts consist of a series of separate segments that together form the linear zone characteristic of rifts. The individual rift segments have a dominantly half-graben geometry, controlled by a single basin-bounding fault. Segment lengths vary between rifts, depending on the elastic thickness of the lithosphere. Areas of thick colder lithosphere, such as

952-459: The present day. The Hessian grabens lie north of the Upper Rhine Graben and follow the same trend. There are two main rift structures, the Wetterau and Leine grabens. They were active during the Oligocene but are inactive now. The easternmost part of the system, the Eger Graben shows two distinct phases of extension at the end of the Eocene and during the early Miocene. The first phase was oblique to

986-404: The product of rifting magmatism at converged plate margins. The sedimentary rocks associated with continental rifts host important deposits of both minerals and hydrocarbons . SedEx mineral deposits are found mainly in continental rift settings. They form within post-rift sequences when hydrothermal fluids associated with magmatic activity are expelled at the seabed. Continental rifts are

1020-403: The rift axis and led to the formation of en-echelon W-E trending fault sets. The second was orthogonal to the rift axis, leading to overprinting of the early W-E faults by later SW-NE trending faults. The rift system is thought to have formed in response to compression of the lithosphere in front of the zones of collision that formed the Alps and Pyrenees. The initial rift propagated northwards as

1054-838: The rift axis. In the Gulf of Suez rift, the Zaafarana accommodation zone is located where a shear zone in the Arabian-Nubian Shield meets the rift. Rift flanks or shoulders are elevated areas around rifts. Rift shoulders are typically about 70 km wide. Contrary to what was previously thought, elevated passive continental margins (EPCM) such as the Brazilian Highlands , the Scandinavian Mountains and India's Western Ghats , are not rift shoulders. The formation of rift basins and strain localization reflects rift maturity. At

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1088-510: The sites of significant oil and gas accumulations, such as the Viking Graben and the Gulf of Suez Rift . Thirty percent of giant oil and gas fields are found within such a setting. In 1999 it was estimated that there were 200 billion barrels of recoverable oil reserves hosted in rifts. Source rocks are often developed within the sediments filling the active rift ( syn-rift ), forming either in

1122-523: The tectonic terms still in use today, despite the fact that almost everything he postulated was later shown to be completely erroneous. The Hans-Stille-Medaille of German Geological Society, awarded annually, is named after him. Also named for him is the mineral stilleite (ZnSe) and the wrinkle ridge Dorsa Stille on the Moon . This article about a German scientist is a stub . You can help Misplaced Pages by expanding it . This biographical article about

1156-655: Was coined by the German geologist Hans Stille in about 1930 to describe a rift in the continental Crust crossing Europe from the Mediterranean Sea via Marseille , the Rhine rift as far as Mjøsa in the south of Norway , a total length of 2000 km. The rift is composed of the following sections: Valley of Rhône in France and its northern continuation the Bresse Rift ,

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