Late Mesozoic – Early Cenozoic structural evolution of - UiO
... reorganization in earliest Oligocene time, Greenland (and North America) moved in a more westerly direction with respect to Eurasia (figure 2.2). Significant marine shallowing took place at the Eocene–Oligocene transition in the Sørvestsnaget Basin (Ryseth et al., 2003). Early Oligocene rifting, rel ...
... reorganization in earliest Oligocene time, Greenland (and North America) moved in a more westerly direction with respect to Eurasia (figure 2.2). Significant marine shallowing took place at the Eocene–Oligocene transition in the Sørvestsnaget Basin (Ryseth et al., 2003). Early Oligocene rifting, rel ...
Rheological heterogeneity, mechanical anisotropy
... deformation of continents. After briefly recapping the concept of rheological stratification of the lithosphere, we discuss two specific issues: (1) as supported by a growing body of geophysical and geological observations, crust=mantle mechanical coupling is usually efficient, especially beneath ma ...
... deformation of continents. After briefly recapping the concept of rheological stratification of the lithosphere, we discuss two specific issues: (1) as supported by a growing body of geophysical and geological observations, crust=mantle mechanical coupling is usually efficient, especially beneath ma ...
LOW RES
... and thermal coupling. Mechanical coupling (viscous traction) between the subducting slab and the base of the mantle wedge drives corner flow [McKenzie, 1969], a type of forced convection. The subducting slab also cools the base of the mantle wedge driving thermal convection (free convection); the co ...
... and thermal coupling. Mechanical coupling (viscous traction) between the subducting slab and the base of the mantle wedge drives corner flow [McKenzie, 1969], a type of forced convection. The subducting slab also cools the base of the mantle wedge driving thermal convection (free convection); the co ...
Reconstructing the Alps–Carpathians–Dinarides as a key to
... triggered by slab tearing and involved widespread intracrustal and crust–mantle decoupling during Adria–Europe collision. In particular, the switch from south-directed European subduction to north-directed “wrong-way” Adriatic subduction beneath the Eastern Alps was preconditioned by two slabtearing ...
... triggered by slab tearing and involved widespread intracrustal and crust–mantle decoupling during Adria–Europe collision. In particular, the switch from south-directed European subduction to north-directed “wrong-way” Adriatic subduction beneath the Eastern Alps was preconditioned by two slabtearing ...
Late Cretaceous–early Cenozoic tectonic evolution of
... prior to the 75 Ma or younger initiation of slip on the Nacimiento fault. Hence, formation of the schists was at least in part a separate phenomenon from the juxtaposition of the Salinian and Nacimiento blocks. On the other hand, both events appear to have been occurring simultaneously sometime betw ...
... prior to the 75 Ma or younger initiation of slip on the Nacimiento fault. Hence, formation of the schists was at least in part a separate phenomenon from the juxtaposition of the Salinian and Nacimiento blocks. On the other hand, both events appear to have been occurring simultaneously sometime betw ...
The ocean-continent transition in the uniform lithospheric stretching
... indeed measured on the deeper portion of the Armorican continental margin and that consequently the mode1 could be accepted at least as a fint approximation. The reason why the transition from continental lithosphere stretching to oceanic accretion should occur for a given stretching factor /3 was, ...
... indeed measured on the deeper portion of the Armorican continental margin and that consequently the mode1 could be accepted at least as a fint approximation. The reason why the transition from continental lithosphere stretching to oceanic accretion should occur for a given stretching factor /3 was, ...
Structural control on present-day topography of a basement massif
... its altitude exceeds 1500m in large areas, reaching 3305m in Jbel Sirwa. Structural contours of the present elevation of a polygenic planation surface (the High Erosional surface) and of the base of Cretaceous and Neogene inliers have been performed to characterize the major tectonic structures. Gen ...
... its altitude exceeds 1500m in large areas, reaching 3305m in Jbel Sirwa. Structural contours of the present elevation of a polygenic planation surface (the High Erosional surface) and of the base of Cretaceous and Neogene inliers have been performed to characterize the major tectonic structures. Gen ...
Mechanical (de-)coupling of the lithosphere in the Valencia Trough
... many geophysical surveys that yielded a highquality database. Signi¢cant parts of these studies have been summarized and reviewed in [29^32]. The rift basin started to open during Late Oligocene over an inverted Mesozoic basin that was subjected to non-deposition and erosion during most of the Paleo ...
... many geophysical surveys that yielded a highquality database. Signi¢cant parts of these studies have been summarized and reviewed in [29^32]. The rift basin started to open during Late Oligocene over an inverted Mesozoic basin that was subjected to non-deposition and erosion during most of the Paleo ...
Receiver function images of the Hellenic subduction zone and
... contact is only incompletely recorded due to the limited station coverage by permanent and temporary networks. In this study, only south of eastern Crete is the plate contact resolved in detail by the dense temporary on-shore/off-shore LIBNET network (Becker et al., 2009). Other temporary networks c ...
... contact is only incompletely recorded due to the limited station coverage by permanent and temporary networks. In this study, only south of eastern Crete is the plate contact resolved in detail by the dense temporary on-shore/off-shore LIBNET network (Becker et al., 2009). Other temporary networks c ...
A petrologic case for Eocene slab break
... 1998). Or, sedimentation might shift elsewhere, as possibly indicated by Eocene through Oligocene clastic sediments in Pakistan and the Indus Fan (Qayyum et al., 1997), lateral to the modern foreland. We also recognize that there are no documented Greater Himalayan plutons or South Tibetan detachmen ...
... 1998). Or, sedimentation might shift elsewhere, as possibly indicated by Eocene through Oligocene clastic sediments in Pakistan and the Indus Fan (Qayyum et al., 1997), lateral to the modern foreland. We also recognize that there are no documented Greater Himalayan plutons or South Tibetan detachmen ...
The global range of subduction zone thermal structures from
... ∼80 km (e.g. Wada and Wang, 2009). The other three Syracuse et al. (2010) models result in similar or colder P–T estimates. The range of P–T conditions predicted for the uppermost part of the basaltic oceanic crust of the 56 subduction segments of Syracuse et al. (2010), (updated van Keken, pers. co ...
... ∼80 km (e.g. Wada and Wang, 2009). The other three Syracuse et al. (2010) models result in similar or colder P–T estimates. The range of P–T conditions predicted for the uppermost part of the basaltic oceanic crust of the 56 subduction segments of Syracuse et al. (2010), (updated van Keken, pers. co ...
Metamorphic reworking of a high pressure–low temperature
... strongly overprinted by a lower pressure assemblage and, along with associated HP/LT rocks, give much younger 40Ar/39Ar ages of 88–55 Ma indicating a later amphibolite facies metamorphic event. We propose therefore that all serpentinite hosted eclogites along the Motagua fault formed at essentially ...
... strongly overprinted by a lower pressure assemblage and, along with associated HP/LT rocks, give much younger 40Ar/39Ar ages of 88–55 Ma indicating a later amphibolite facies metamorphic event. We propose therefore that all serpentinite hosted eclogites along the Motagua fault formed at essentially ...
Ridge subduction and porphyry copper
... For example, there are several subducting ridges along the east Pacific margin, e.g., in Chile, Peru, and South America, most of which are associated with large porphyry Cu-Au deposits. In contrast, there are much fewer ridge subductions on the west Pacific margin and porphyry Cu-Au deposits are muc ...
... For example, there are several subducting ridges along the east Pacific margin, e.g., in Chile, Peru, and South America, most of which are associated with large porphyry Cu-Au deposits. In contrast, there are much fewer ridge subductions on the west Pacific margin and porphyry Cu-Au deposits are muc ...
Bresse Graben System, European Crust and Topo Europe
... processes took place during the Alpine orogeny in conjunction with subduction and the Moho discontinuity was depressed to depths of 60 km to 75 km. Nowadays the maximum amount of the crustal thickness in the Alps region lies about 55 km. The thickening is accompanied by metamorphism and plutonic act ...
... processes took place during the Alpine orogeny in conjunction with subduction and the Moho discontinuity was depressed to depths of 60 km to 75 km. Nowadays the maximum amount of the crustal thickness in the Alps region lies about 55 km. The thickening is accompanied by metamorphism and plutonic act ...
Subduction erosion modes: Comparing finite
... have been estimated in the central Andes due to subduction erosion (Kukowski and Oncken, 2006). Elsewhere, higher rates of ca. 10 km Ma− 1 have been associated with topographic asperities on the lower plate (e.g. Clift et al., 2003). Possible mechanisms for this mode of subduction erosion include du ...
... have been estimated in the central Andes due to subduction erosion (Kukowski and Oncken, 2006). Elsewhere, higher rates of ca. 10 km Ma− 1 have been associated with topographic asperities on the lower plate (e.g. Clift et al., 2003). Possible mechanisms for this mode of subduction erosion include du ...
Evolution of the southeastern Lachlan Fold Belt in Victoria
... with high T/low P metamorphism. The orogen-parallel movement (north–south) is in addition to a stronger component of east–west contraction. Three main orogenic pulses deformed the Victorian portion of the terrane. The earliest, the Benambran Orogeny, was the major cratonisation event in the Lachlan ...
... with high T/low P metamorphism. The orogen-parallel movement (north–south) is in addition to a stronger component of east–west contraction. Three main orogenic pulses deformed the Victorian portion of the terrane. The earliest, the Benambran Orogeny, was the major cratonisation event in the Lachlan ...
Thrusting, Active Back Thrusting and Tectonic Wedging: An Example
... tectonic wedge of Paleozoic-Paleocene rocks inserted underneath the Eocene-Pliocene rocks. The tectonic wedge comprises north-south trending Makarwal Anticline that has developed above a ramp from basal décollement within Paleozoic-Mesozoic rocks and forms the base of the wedge. The ramp beneath the ...
... tectonic wedge of Paleozoic-Paleocene rocks inserted underneath the Eocene-Pliocene rocks. The tectonic wedge comprises north-south trending Makarwal Anticline that has developed above a ramp from basal décollement within Paleozoic-Mesozoic rocks and forms the base of the wedge. The ramp beneath the ...
2014-Wannamaker-Casc.. - University of Alberta
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
- Wiley Online Library
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
GEOLOGICAL EVOLUTION AND BASIN MODELS
... In the Bingöl-Karlıova area, the Lower Miocene consists of Adilcevaz limestone. The Adilcevaz unconformably overlies the basement strata and have sandy limestones at its very base. The Adilcevaz limestone is exposed at very small localities along the North Anatolian fault. Fossils found in the limes ...
... In the Bingöl-Karlıova area, the Lower Miocene consists of Adilcevaz limestone. The Adilcevaz unconformably overlies the basement strata and have sandy limestones at its very base. The Adilcevaz limestone is exposed at very small localities along the North Anatolian fault. Fossils found in the limes ...
The structure and dynamics of the mantle wedge
... constraints on the pathways of £uid and melt migration from the slab to the volcanic arc. Composition of arc lavas Chemical analyses of arc lavas provide fundamental constraints on the temperature and pressure conditions and the role of water in subduction zones. Glass inclusions in ma¢c arc lavas e ...
... constraints on the pathways of £uid and melt migration from the slab to the volcanic arc. Composition of arc lavas Chemical analyses of arc lavas provide fundamental constraints on the temperature and pressure conditions and the role of water in subduction zones. Glass inclusions in ma¢c arc lavas e ...
Slab behaviour and its surface expression: new insights
... with mass excess (lithospheric thickening; Fig. 1d) in the subsurface. In both cases, Bouguer and free-air anomalies are the same for the uncompensated stage (Fig. 1b,d). The broad free-air anomalies indicate that isostatic equilibrium is not realized and the Bouguer anomalies reveal the uncompensat ...
... with mass excess (lithospheric thickening; Fig. 1d) in the subsurface. In both cases, Bouguer and free-air anomalies are the same for the uncompensated stage (Fig. 1b,d). The broad free-air anomalies indicate that isostatic equilibrium is not realized and the Bouguer anomalies reveal the uncompensat ...
Formation and Exhumation of Ultrahigh
... The earliest models for UHP tectonism assumed that it occurs during subduction of a continental margin because the metamorphic pressure–temperature (P–T) conditions of UHP rocks are typical of subduction zones and not of overthickened continental collision zones, such as the Tibetan Plateau. A secon ...
... The earliest models for UHP tectonism assumed that it occurs during subduction of a continental margin because the metamorphic pressure–temperature (P–T) conditions of UHP rocks are typical of subduction zones and not of overthickened continental collision zones, such as the Tibetan Plateau. A secon ...
1 The role of the mantle wedge in subduction zone dynamics and
... structure of the mantle wedge is characterized by an extensive zone of low seismic velocity that connects the plate-wedge interface between 150 and 200 km depth to the volcanic front or back arc basins [25-30] although in some cases, such as in the Bolivian Andes, the velocity and Q anomalies in the ...
... structure of the mantle wedge is characterized by an extensive zone of low seismic velocity that connects the plate-wedge interface between 150 and 200 km depth to the volcanic front or back arc basins [25-30] although in some cases, such as in the Bolivian Andes, the velocity and Q anomalies in the ...
Metamorphic reworking of a high - Lamont
... strongly overprinted by a lower pressure assemblage and, along with associated HP/LT rocks, give much younger 40Ar/39Ar ages of 88–55 Ma indicating a later amphibolite facies metamorphic event. We propose therefore that all serpentinite hosted eclogites along the Motagua fault formed at essentially ...
... strongly overprinted by a lower pressure assemblage and, along with associated HP/LT rocks, give much younger 40Ar/39Ar ages of 88–55 Ma indicating a later amphibolite facies metamorphic event. We propose therefore that all serpentinite hosted eclogites along the Motagua fault formed at essentially ...