| Here, rifting took place in the Early Griesbachian and the Late Griesbachian, respectively, based on ammonoid data and radiometric dating. |
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| After obduction, there was a slow rate of subsidence, which reflects the continuing cooling of the underlying Indian lithosphere after rifting. |
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| The early Cretaceous is characterized by relative quiescence and thermal subsidence following late Jurassic rifting. |
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| Pre-Aptian structure reflects both Palaeozoic rifting and Mesozoic modification. |
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| Particularly important for British landscape development was rifting of the Greenland-European plate in the early Paleocene. |
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| In the northern Cordillera lower Paleozoic alkalic and potassic mafic magmatism is linked with rifting of the Selwyn Basin. |
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| The Early Triassic rifting episode followed the older Devonian and Carboniferous structural grains. |
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| An active origin is suggested because volcanism and uplift appear to have preceded rifting, an active plume passing over a large area. |
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| Major crustal rifting has also played a part in the evolution of large bodies of Proterozoic sedimentary and igneous rocks. |
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| However, there seems to be a marked age gap between the Cretaceous ages and onset of rifting in the Eocene. |
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| This multiphase rifting led to the formation of distinct structural domains along the passive margin. |
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| Although Early Triassic rifting in East Greenland and west of Norway has been described previously, limited evidence has been presented, mainly because of absence of data. |
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| The latter interpretation is compatible with an episode of rifting and sedimentation in a system of tilted blocks. |
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| The early Permian rifting in the North Atlantic involved siliciclastic sedimentation in extensional basins and widespread extrusive and intrusive magmatic activity. |
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| This ancient seaway was later to extend farther westward to Gibraltar as rifting between Laurasia and Gondwana began in the Late Triassic. |
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| Simultaneously, rifting along the Ouachitas led to the separation of Yucatán, creating the Gulf of Mexico in its wake. |
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| Some magmatic activity is concentrated along basement lineaments and other volcanism appears to be related to rifting in a similar way to that of major rift valleys. |
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| The collision was followed by rifting of the Cimmerian suture during Early Jurassic time to form a new oceanic basin between the Taurides-Anatolides and Eurasia. |
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| And some of the forces behind this rifting process may constitute a major threat leading to devastating disasters. |
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| During the geological evolution of this region there has been rifting of the crust and extensive movement of the plates. |
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| The presence of extrusive volcanic rocks during the rifting stages suggests that a large volume of melt may also have been added to the crust intrusively. |
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| The contrasting aspects of rifting and volcanism in the East African and Central-East Asian rifts were compared by T. Barry and co-workers. |
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| The volcanic and sedimentary rocks that formed at the time of rifting belong to the Middle Keweenawan Supergroup. |
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| The Stikine belt forms from crustal rifting, the Anahim belt from a hot spot and the Garibaldi belt from subduction. |
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| As rifting proceeds, seafloor spreading occurs and an up-welling melt creates the oceanic crust. |
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| In Figure 3a, almost 7 Ma after the initiation of rifting, the flow in the asthenosphere is well behaved and directed into the developing rift. |
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| The models are two dimensional and solve for the temperature structure and flow velocities in the asthenosphere that result from rifting. |
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| Rift basins in the Red Sea area developed in terranes accreted in Pan-African time, and it is believed that some of these ancient sutures controlled later Red Sea rifting. |
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| Magma invades the cracks, and the process of continental rifting, ultimately leading to seafloor spreading, begins. |
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| It paid special attention to the early stages of rifting in continental plates. |
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| By the beginning of the Cretaceous, the supercontinent Pangea was already rifting apart, and by the mid-Cretaceous, it had split into several smaller continents. |
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| This may have been repeated several times, with the Benue Trough deformed between rifting episodes. |
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| Continental collision makes fewer and larger continents while rifting makes more and smaller continents. |
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| Spreading in the West Scotia Sea finally led to the rifting of the South Orkney microcontinent from the tip of the Antarctic Peninsula. |
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| Lake Superior Provincial Park's 2.6 billion year geological history is one of intense volcanic activity, mountain building, faulting, rifting and glaciation. |
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| Extensive basaltic volcanism accompanied that rifting event, followed by a period of heavy sedimentation along a northeast-facing continental margin. |
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| The present-day Mediterranean seafloor was formed during a complex sequence of rifting between small plates in this region, beginning with the separation of North America and Europe from Africa about 200 million years ago. |
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| How do the dynamics of rifting affect resources? |
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| The oldest rocks are late Precambrian Windermere strata comprised of coarse sandstones, shales and slates, and very minor volcanic rocks that were laid down during the initial rifting stage. |
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| The high temperature of the hot spot, arriving during the continental rifting stage, induces the large volume of melt that creates the thick igneous crust. |
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| The main topics concerned basin evolution, the dynamics of rifting, crustal structure, tectonic modelling, research and diving in the Dead Sea, and the Dead Sea rift. |
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| Second, as rifting progressed through Early and Middle Jurassic time, continental crust was stretched and thinned. |
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| This flooded the subsiding basin created by rifting and crustal thinning to create the Gulf of Mexico. |
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| There was a second episode of rifting and separation, which started about 360 million years ago and initiated a basin floored by oceanic crust that today is represented by Slide Mountain terrane in the Omineca Belt. |
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| Those igneous rocks formed in the faulted and thinned continental margin of northwestern Europe contemporaneously with the rifting and seafloor spreading that gave rise to the Atlantic Ocean. |
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| They discussed the role of mantle plumes, preexisting orogenic fabric of the plates and strike-slip faulting on the rifting initiation and development. |
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| Description: The project aimed at a better understanding of the Cenozoic geodynamics of rifting and sedimentary basin formation in their complex intraplate environment. |
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| Further insights on continental rifting was given by A. Tommasi and A. Vauchez, from the observation and modelling of the mechanical anisotropy of the lithospheric Mantle. |
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| The rifting took place in the Paleoproterozoic around 1864 Ma, and was followed by E W orientated compressional deformation ca. 1850 Ma with the development of northerly trending isoclinal folds and associated faults. |
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| Crustal magnetic studies on the Krishna-Godavari basin identified a rifting of the Dharwar and Bastar cratons within the Indian plate, prior to the rifting of India from Gondwanaland. |
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| Superposed horst and graben structures were identified, and are correlated to the formation of the Krishna-Godavari basin as a result of the rifting and drifting of India from Gondwanaland. |
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| Such active rifting lifted great undersea mountain chains along the welts, raising eustatic sea levels worldwide. |
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| Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. |
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| During rifting, as the crust is thinned, the Earth's surface subsides and the Moho becomes correspondingly raised. |
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| Some rifts show a complex and prolonged history of rifting, with several distinct phases. |
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| Many rifts are the sites of at least minor magmatic activity, particularly in the early stages of rifting. |
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| These are interpreted as evidence that by that time, rifting had started that would form the Iapetus Ocean. |
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| The rifting that took place between North America and Africa produced multiple failed rifts. |
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| The emergence of deep basins in the Caribbean occurred during the Middle Jurassic rifting. |
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| The African Plate is rifting in the eastern interior of the African continent along the East African Rift. |
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| The transition between the continental and oceanic lithosphere that was originally created by rifting is known as a passive margin. |
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| Different kinds of transitional crust form, depending on how fast rifting occurs and how hot the underlying mantle was at the time of rifting. |
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| This type of passive margin develops where rifting is oblique to the coastline, as is now occurring in the Gulf of California. |
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| The Benue Trough was formed by rifting of the central West African basement, beginning at the start of the Cretaceous period. |
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| Continental rifting commonly follows flood basalt volcanism. |
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| At 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. |
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| By the beginning of the Jurassic, the supercontinent Pangaea had begun rifting into two landmasses, Laurasia to the north and Gondwana to the south. |
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| The ridge marks the boundary between the Eurasian and North American Plates, and Iceland was created by rifting and accretion through volcanism along the ridge. |
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| The rifting was associated with zones of weakness within Pangea, including sutures where the Laurentia, South American, and African plates collided to create it. |
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| Geologists and other Earth scientists agree in general that the present Gulf of Mexico basin originated in Late Triassic time as the result of rifting within Pangea. |
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