Ocean Basin Evolution and Global
... subduction zones (Bird 2003)—and so its motion is defined relative to the neighboring Eurasian or Pacific plates (e.g., Seton et al. 2012, Zahirovic et al. 2014). Relative motions between plates that are determined by marine magnetic anomalies and fracture zones on preserved ocean crust are consider ...
... subduction zones (Bird 2003)—and so its motion is defined relative to the neighboring Eurasian or Pacific plates (e.g., Seton et al. 2012, Zahirovic et al. 2014). Relative motions between plates that are determined by marine magnetic anomalies and fracture zones on preserved ocean crust are consider ...
Anomalous Occurrence of Cretaceous Placer Deposits: A
... deep weathering at that time. Economically important minerals were reworked from their primary sources during these Cretaceous weathering events. The extreme global warmth witnessed in the Cretaceous also caused the melting of most of the polar ice caps, resulting in the expansion of the volume of C ...
... deep weathering at that time. Economically important minerals were reworked from their primary sources during these Cretaceous weathering events. The extreme global warmth witnessed in the Cretaceous also caused the melting of most of the polar ice caps, resulting in the expansion of the volume of C ...
Hydrogeology of the coastal plain between
... The hydrogeology of the coastal plain between Cervantes and Leeman in the northern Perth Basin has been investigated by drilling 33 bores at 17 sites on a 7 km grid. The bores were drilled between March and May 1993, with the exception of bores 8A and 8B which were drilled in October 1990, and they ...
... The hydrogeology of the coastal plain between Cervantes and Leeman in the northern Perth Basin has been investigated by drilling 33 bores at 17 sites on a 7 km grid. The bores were drilled between March and May 1993, with the exception of bores 8A and 8B which were drilled in October 1990, and they ...
Proterozoic subduction-related and continental rift
... he argued that the circum-oceanic basalts cannot be derived by assimilation of continental crust by OIBs. Chayes7 suggested that the geochemical differences between the two types of basalt originated in the mantle itself. Based on experimental studies in the system MgO– SiO2–TiO2 , MacGregor8 sugges ...
... he argued that the circum-oceanic basalts cannot be derived by assimilation of continental crust by OIBs. Chayes7 suggested that the geochemical differences between the two types of basalt originated in the mantle itself. Based on experimental studies in the system MgO– SiO2–TiO2 , MacGregor8 sugges ...
Generation of plate tectonics from mantle convection
... about the plate-tectonic style of mantle convection. Closely related to these modes of plate boundary deformation is the composition of the present-day velocity field in terms of poloidal and toroidal components (see Section 7.07.3.7). Poloidal flow is essentially the vertical convective circulation ...
... about the plate-tectonic style of mantle convection. Closely related to these modes of plate boundary deformation is the composition of the present-day velocity field in terms of poloidal and toroidal components (see Section 7.07.3.7). Poloidal flow is essentially the vertical convective circulation ...
A Geology Training Manual for Grand Canyon National
... been opened by processes of erosion and weathering. As you look through this book you may notice that some of the pages have been ripped out, and others were never written. But before you can begin to read this geologic story, you should first understand the words and the language the book is writte ...
... been opened by processes of erosion and weathering. As you look through this book you may notice that some of the pages have been ripped out, and others were never written. But before you can begin to read this geologic story, you should first understand the words and the language the book is writte ...
Hafnium isotope evidence for slab melt contributions in the Central
... et al., 2008), although the same types of observations have also been used to argue for crustal assimilation (e.g., Siebe et al., 2004; Schaaf et al., 2005; Torres-Alvarado et al., 2011). However these studies did not report Hf isotope ratios which, as we show here, add important supporting evidence ...
... et al., 2008), although the same types of observations have also been used to argue for crustal assimilation (e.g., Siebe et al., 2004; Schaaf et al., 2005; Torres-Alvarado et al., 2011). However these studies did not report Hf isotope ratios which, as we show here, add important supporting evidence ...
Ophiolite concept and its evolution
... than any other topic in geology, and the questions and problems raised and resolved during the course of these studies have made significant contributions to the evolution of geological thought over the years. The topic of ophiolites (their definition, tectonic origin, emplacement mechanisms, etc.) ...
... than any other topic in geology, and the questions and problems raised and resolved during the course of these studies have made significant contributions to the evolution of geological thought over the years. The topic of ophiolites (their definition, tectonic origin, emplacement mechanisms, etc.) ...
Volcanogenic Massive Sulfide Deposits
... systems. In the last 25 years, mapping of the seafloor also has allowed more precise tectonic classifications of VMS-hosting environments based on improved geodynamic models of submarine volcanic arcs, back-arc spreading centers, and midocean ridges (Hannington et al., 2005). Franklin et al. (2005) ...
... systems. In the last 25 years, mapping of the seafloor also has allowed more precise tectonic classifications of VMS-hosting environments based on improved geodynamic models of submarine volcanic arcs, back-arc spreading centers, and midocean ridges (Hannington et al., 2005). Franklin et al. (2005) ...
PDF (Chapter 10. Isotopes)
... traverse the shallow mantle on their way to the surface. The crust is extremely enriched in many of the socalled incompatible elements, generally the large ionic radius or high-charge elements that do not readily fit into the lattices of the "major mantle minerals," olivine and orthopyroxene. The cr ...
... traverse the shallow mantle on their way to the surface. The crust is extremely enriched in many of the socalled incompatible elements, generally the large ionic radius or high-charge elements that do not readily fit into the lattices of the "major mantle minerals," olivine and orthopyroxene. The cr ...
Makhtesh Ramon Geological Window, hyper
... the MR area and less soils. The area is mostly free of clouds throughout the year, and several weather stations that collect information on a diurnal basis have been dispersed throughout the area. The MR area is known as one of the most important mineralogical sites in Israel and has been called a “ ...
... the MR area and less soils. The area is mostly free of clouds throughout the year, and several weather stations that collect information on a diurnal basis have been dispersed throughout the area. The MR area is known as one of the most important mineralogical sites in Israel and has been called a “ ...
Second Draft with Art and Photos September 2006
... seismic event, as shown by the curved bands radiating out form the hypocenter. These waves can be measured some time later by seismic stations, such as at locations 1 and 2. Seismic stations closer to the hypocenter, such as station 1, will detect it sooner than those farther away, like station 2. 2 ...
... seismic event, as shown by the curved bands radiating out form the hypocenter. These waves can be measured some time later by seismic stations, such as at locations 1 and 2. Seismic stations closer to the hypocenter, such as station 1, will detect it sooner than those farther away, like station 2. 2 ...
Isostasy, dynamic topography, and the elevation of the Apennines of
... compared with geodetic and geological data to infer uplift and subsidence histories. The result of this comparative analysis is used to quantify the relative contribution of isostatic and dynamic components, providing new insights on the range of subduction processes contributing to the topography a ...
... compared with geodetic and geological data to infer uplift and subsidence histories. The result of this comparative analysis is used to quantify the relative contribution of isostatic and dynamic components, providing new insights on the range of subduction processes contributing to the topography a ...
Spatial, temporal and geochemical evolution of
... continent to the north and Anatolide–Tauride Platform to the south of the ~ E–W-trending Izmir–Ankara suture zone (IASZ) during the late Oligocene–middle Miocene. We report here a comprehensive geochronological (combined zircon U–Pb and 40Ar–39Ar dating) and geochemical (major and trace element geoc ...
... continent to the north and Anatolide–Tauride Platform to the south of the ~ E–W-trending Izmir–Ankara suture zone (IASZ) during the late Oligocene–middle Miocene. We report here a comprehensive geochronological (combined zircon U–Pb and 40Ar–39Ar dating) and geochemical (major and trace element geoc ...
geo.tu-freiberg.de - TU Bergakademie Freiberg
... the sense of Cotta, who has done his phd on silicified woods from the Rotliegend, who has further worked on field mapping projects in Saxony and Thuringia, who has documented many drillings and who has evaluated the coal deposits in Saxony as a competent expert. Furthermore, Cotta was interested in ...
... the sense of Cotta, who has done his phd on silicified woods from the Rotliegend, who has further worked on field mapping projects in Saxony and Thuringia, who has documented many drillings and who has evaluated the coal deposits in Saxony as a competent expert. Furthermore, Cotta was interested in ...
Earth Planet. Sci. Lett., 139, 1-16, 1996.
... seafloor age, using the standard thermal-plate model [9]. The superswell hypothesis relies heavily on recognizing a depth anomaly which has a magnitude and spatial distribution inconsistent with the simple superposition of anomalies attributed to the individual hot-spots identified in the region [17 ...
... seafloor age, using the standard thermal-plate model [9]. The superswell hypothesis relies heavily on recognizing a depth anomaly which has a magnitude and spatial distribution inconsistent with the simple superposition of anomalies attributed to the individual hot-spots identified in the region [17 ...
Anderson and Natland, 2005
... tectonics was being developed in the west, V.V. Beloussov in Russia was formulating his theory of vertical tectonics, or mantle diapirism, in order to explain continental geology. His text, published in 1956 in Russian, was translated into English in 1962, the year of publication of Hess’s enunciati ...
... tectonics was being developed in the west, V.V. Beloussov in Russia was formulating his theory of vertical tectonics, or mantle diapirism, in order to explain continental geology. His text, published in 1956 in Russian, was translated into English in 1962, the year of publication of Hess’s enunciati ...
Is the rate of supercontinent assembly changing with time?
... We still have many questions regarding the supercontinent cycle, such as when it began, has continental crust grown in volume with time, and has the period of the cycle been constant or has it changed with time. The timescale of assembly and dispersal of supercontinents is still not well constrained ...
... We still have many questions regarding the supercontinent cycle, such as when it began, has continental crust grown in volume with time, and has the period of the cycle been constant or has it changed with time. The timescale of assembly and dispersal of supercontinents is still not well constrained ...
A trace element perspective on the source of ocean island basalts
... We analyze the first-order observations, basic concepts and explicit/implicit assumptions built into the three major hypotheses for the enriched component(s) in the source of ocean island basalts (OIB) in terms of incompatible trace elements: (1) subducted ocean crust (SOC), (2) subducted continenta ...
... We analyze the first-order observations, basic concepts and explicit/implicit assumptions built into the three major hypotheses for the enriched component(s) in the source of ocean island basalts (OIB) in terms of incompatible trace elements: (1) subducted ocean crust (SOC), (2) subducted continenta ...
A long in situ section of the lower ocean crust: results of ODP Leg
... core. Igneous mineralogy was point-counted on over 200 thin sections, and detailed semi-quantitative petrographic descriptions of rock alteration, deformation and igneous textures were made on 285 thin sections. The scientists worked in disciplinary teams, with the igneous petrologists, metamorphic ...
... core. Igneous mineralogy was point-counted on over 200 thin sections, and detailed semi-quantitative petrographic descriptions of rock alteration, deformation and igneous textures were made on 285 thin sections. The scientists worked in disciplinary teams, with the igneous petrologists, metamorphic ...
History of geology
The history of geology is concerned with the development of the natural science of geology. Geology is the scientific study of the origin, history, and structure of the Earth. Throughout the ages geology provides essential theories and data that shape how society conceptualizes the Earth.