RIFT Research Papers - Academia.edu (original) (raw)

The Roer Valley Rift System (RVRS) is located between the West European rift and the North Sea rift system. During the Cenozoic, the RVRS was characterized by several periods of subsidence and inversion, which are linked to the evolution... more

The Roer Valley Rift System (RVRS) is located between the West European rift and the North Sea rift system. During the Cenozoic, the RVRS was characterized by several periods of subsidence and inversion, which are linked to the evolution of the adjacent rift systems. Combination of subsidence analysis and results from the analysis of thickness distributions and fault systems allows the determination of the Cenozoic evolution and quantification of the subsidence. During the Early Paleocene, the RVRS was inverted (Laramide phase). The backstripping method shows that the RVRS was subsequently mainly affected by two periods of subsidence, during the Late Paleocene and the Oligocene–Quaternary time intervals, separated by an inversion phase during the Late Eocene. During the Oligocene and Miocene periods, the thickness of the sediments and the distribution of the active faults reveal a radical rotation of the direction of extension by about 70–80° (counter clockwise). Integration of these results at a European scale indicates that the Late Paleocene subsidence was related to the evolution of the North Sea basins, whereas the Oligocene–Quaternary subsidence is connected to the West European rift evolution. The distribution of the inverted provinces also shows that the Early Paleocene inversion (Laramide phase) has affected the whole European crust, whereas the Late Eocene inversion was restricted to the southern North Sea basins and the Channel area. Finally, comparison of these deformations in the European crust with the evolution of the Alpine chain suggests that the formation of the Alps has controlled the evolution of the European crust since the beginning of the Cenozoic.

Abstract The sierra de Chacaico (Neuquén, Argentina) is one of the most important localities to study the Upper Triassic-Lower Jurassic syn-rift sequence of the Neuquén Basin. Structural and sedimentological analyses have been carried out... more

Abstract The sierra de Chacaico (Neuquén, Argentina) is one of the most important localities to study the Upper Triassic-Lower Jurassic syn-rift sequence of the Neuquén Basin. Structural and sedimentological analyses have been carried out in order to depict the stratigraphic evolution of the infill. The syn-rift sequence evolved in a volcano-sedimentary environment. For the entire column, three sections have been recognized.

U Pb ages have been obtained for the Muskox intrusion and the Mackenzie dyke swarm. The age of a pyroxenite from the layered series of the intrusion is 1270 ± 4Ma. Baddeleyite fractions from four widely-spaced Mackenzie diabases define a... more

U Pb ages have been obtained for the Muskox intrusion and the Mackenzie dyke swarm. The age of a pyroxenite from the layered series of the intrusion is 1270 ± 4Ma. Baddeleyite fractions from four widely-spaced Mackenzie diabases define a single discordia line with an upper ...

Editors' note: The manuscript was submitted in July 1998 and has been revised at the authors' discretion. ABSTRACT The western Snake River Plain is a Neogene-aged intracontinental rift basin, about 70 km wide and 300 km long,... more

Editors' note: The manuscript was submitted in July 1998 and has been revised at the authors' discretion. ABSTRACT The western Snake River Plain is a Neogene-aged intracontinental rift basin, about 70 km wide and 300 km long, trending northwest across the southern Idaho batholith. Its southeastern end merges with the northeast-trending eastern plain, a structural downwarp associated with extension along the track of the Yellowstone hot spot. Orientation of the western plain rift is parallel to several regional northwest-trending crustal discontinuities, such as the Olympic-Wallowa lineament and the Brothers fault zone, suggesting that the rift failed along zones of litho-spheric weakness, as the lithosphere was softened by the passing hot spot. Crustal refraction data and gravity show that the rift is not simply underlain by granitic rock, de-spite its appearance of having broken and extended the southern end of the Idaho batholith. Instead, the crust beneath 1 to 2 km of ba...