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 ...
The Model of Oceanic Crust Expansion
... V refers to the incremental quantity of the volume of the earth’s mantle in the phase of expansion; Tv refers to the state variant of the solid matters within the earth in the phase of expansion; 0.097 refers to the comprehensive volume changing coefficient of the earth’s matters (1500 degrees); Pv ...
... V refers to the incremental quantity of the volume of the earth’s mantle in the phase of expansion; Tv refers to the state variant of the solid matters within the earth in the phase of expansion; 0.097 refers to the comprehensive volume changing coefficient of the earth’s matters (1500 degrees); Pv ...
Mapping the evolving strain field during continental breakup from
... in Oligo-Miocene times14. Since < 4 Myr ago, however, volcanism and dyke-induced normal faulting have localized to ~15-km-wide, ~60-km-long axial volcanic ranges with aligned chains of basaltic cones and fissural flows12,15. These Quaternary-Recent magmatic segments (for example, Dabbahu segment) a ...
... in Oligo-Miocene times14. Since < 4 Myr ago, however, volcanism and dyke-induced normal faulting have localized to ~15-km-wide, ~60-km-long axial volcanic ranges with aligned chains of basaltic cones and fissural flows12,15. These Quaternary-Recent magmatic segments (for example, Dabbahu segment) a ...
Caribbean Basins - Red Cubana de la Ciencia
... There have been many previous classifications and regional studies of Caribbean sedimentary basins within a plate-tectonic framework. Gonzalez de Juana et al. (1980) carried out a thorough compilation on sedimentary basins in Venezuela for the Venezuelan oil industry. Burke et al. (1984) compiled in ...
... There have been many previous classifications and regional studies of Caribbean sedimentary basins within a plate-tectonic framework. Gonzalez de Juana et al. (1980) carried out a thorough compilation on sedimentary basins in Venezuela for the Venezuelan oil industry. Burke et al. (1984) compiled in ...
subduction to strike-slip transitions on plate boundaries
... suggests an Andean high-K calc-alkaline provenance. Facies relations, paleontologic data and regional geologic setting suggest sediment accumulation on an inner trench slope in a basin situated oceanward of the Pliocene trench-slope break. Faulting is extensive and reflects two deformational episode ...
... suggests an Andean high-K calc-alkaline provenance. Facies relations, paleontologic data and regional geologic setting suggest sediment accumulation on an inner trench slope in a basin situated oceanward of the Pliocene trench-slope break. Faulting is extensive and reflects two deformational episode ...
The Statistical Upper Mantle Assemblage, Earth
... The geochemical diversity of mid-ocean ridge basalt (MORB) and oceanic island basalt (OIB) has traditionally been attributed to the existence of large-scale mantle heterogeneity, in particular to accessible reservoirs at various depths. However, reconciling the geochemical constraints for isolated, ...
... The geochemical diversity of mid-ocean ridge basalt (MORB) and oceanic island basalt (OIB) has traditionally been attributed to the existence of large-scale mantle heterogeneity, in particular to accessible reservoirs at various depths. However, reconciling the geochemical constraints for isolated, ...
52. eratosthenes seamount: an oceanographic yardstick recording
... chalks of Coniacian–Maastrichtian to middle Eocene age recovered from the Eratosthenes Seamount at Site 967 are also comparable with similar sedimentary units in the Levant. Both the southern margin of the Levant basin and the Eratosthenes Seamount subsided to bathyal depths during Late Cretaceous–P ...
... chalks of Coniacian–Maastrichtian to middle Eocene age recovered from the Eratosthenes Seamount at Site 967 are also comparable with similar sedimentary units in the Levant. Both the southern margin of the Levant basin and the Eratosthenes Seamount subsided to bathyal depths during Late Cretaceous–P ...
2.3. New Zealand – Primary Site 1. Background and Motivation
... the North, there is a rich record of active and ancient subduction margin processes, from subduction initiation through to fully developed, mature subduction systems. For simplicity, the seven SCD key questions (Section 2.1) can be organized into four overarching questions to be addressed at the New ...
... the North, there is a rich record of active and ancient subduction margin processes, from subduction initiation through to fully developed, mature subduction systems. For simplicity, the seven SCD key questions (Section 2.1) can be organized into four overarching questions to be addressed at the New ...
Niu, Y., Generation and evolution of basaltic magmas
... felsic (i.e., higher SiO2) or less mafic (i.e., lower FeO and MgO, and lower MgO/FeO ratio) than the source rock. In other words, basaltic melts result from partial melting of mantle peridotites; partial melting of basaltic rocks (basalts, diabases, gabbros etc.) cannot produce basaltic melts, but m ...
... felsic (i.e., higher SiO2) or less mafic (i.e., lower FeO and MgO, and lower MgO/FeO ratio) than the source rock. In other words, basaltic melts result from partial melting of mantle peridotites; partial melting of basaltic rocks (basalts, diabases, gabbros etc.) cannot produce basaltic melts, but m ...
alps vs apennines - Dipartimento di Scienze della Terra
... 1975) or to the westward drift of the lithosphere relative to the underlying mantle (DOGLIONI et alii, 1999b). The same different interpretations have been used for differentiating the Alps and the Apennines as related to different slab pull effect (ROYDEN & BURCHFIEL, 1989; ROYDEN, 1993), or as rel ...
... 1975) or to the westward drift of the lithosphere relative to the underlying mantle (DOGLIONI et alii, 1999b). The same different interpretations have been used for differentiating the Alps and the Apennines as related to different slab pull effect (ROYDEN & BURCHFIEL, 1989; ROYDEN, 1993), or as rel ...
SEDIMENTARY BASINS BASIN TYPES ACCORDING TO
... a proto-oceanic rift system) is established when two divergent continents separate and new oceanic crust forms in the intervening space. This does not necessarily mean that such a basin type fills with oceanic sediments, but it does imply that the central basin floor lies at least 2 to 3 km below se ...
... a proto-oceanic rift system) is established when two divergent continents separate and new oceanic crust forms in the intervening space. This does not necessarily mean that such a basin type fills with oceanic sediments, but it does imply that the central basin floor lies at least 2 to 3 km below se ...
stratigraphy and history of raton basin and notes on san luis basin
... the region of the present Raton basin and buried the late Paleozoic, Sierra Grande, and Apishapa uplifts. Cretaceous marine shale interbedded with some sandstone blanketed the entire region. The Cretaceous rocks are about 4,500 feet thick at the north, and remnants in the Las Vegas subbasin are 900- ...
... the region of the present Raton basin and buried the late Paleozoic, Sierra Grande, and Apishapa uplifts. Cretaceous marine shale interbedded with some sandstone blanketed the entire region. The Cretaceous rocks are about 4,500 feet thick at the north, and remnants in the Las Vegas subbasin are 900- ...
geology area south of magadi
... General.—The area south of Magadi as denned for this report is the part of the northwest quarter of Degree Sheet 58 (Kenya: Sheet No. 171 of the Directorate of Overseas Surveys) north of the Kenya-Tanganyika interterritorial boundary. It is bounded by longitudes 36° 00' and 36° 30' E. and by latitud ...
... General.—The area south of Magadi as denned for this report is the part of the northwest quarter of Degree Sheet 58 (Kenya: Sheet No. 171 of the Directorate of Overseas Surveys) north of the Kenya-Tanganyika interterritorial boundary. It is bounded by longitudes 36° 00' and 36° 30' E. and by latitud ...
Ocean Rises are Products of Variable Mantle Composition
... attributed to mantle plumes underlying mantle hotspots, areas of enormous volcanism marked by ocean islands. The plumes are thought to feed the mantle beneath adjacent ocean ridges. This results in thickened crust and ridge elevation to form ocean rises. The composition of mid-ocean ridge basalt, a ...
... attributed to mantle plumes underlying mantle hotspots, areas of enormous volcanism marked by ocean islands. The plumes are thought to feed the mantle beneath adjacent ocean ridges. This results in thickened crust and ridge elevation to form ocean rises. The composition of mid-ocean ridge basalt, a ...
a short story about the geological history of the pamir
... The Tadjik sedimentary basin is divided into two domains by the Vakhsh and Trans-Alai overthrusts. The “Tien Shan” domain comprises the South Tien Shan and the central and western parts of the Tadjik Depression. The “Outer Pamir” domain includes the Pamir Alai region and the eastern part of the Tadj ...
... The Tadjik sedimentary basin is divided into two domains by the Vakhsh and Trans-Alai overthrusts. The “Tien Shan” domain comprises the South Tien Shan and the central and western parts of the Tadjik Depression. The “Outer Pamir” domain includes the Pamir Alai region and the eastern part of the Tadj ...
Hotspot Geodynamics Detailed Planning Group
... current information, methods and models, and to develop an optimal global drilling plan (including drilling, logging and post-cruise science) to address: 1. The minimal/optimal paleomagnetic observations necessary to distinguish whole Earth motion (“true polar wander”) from hotspot drift; that is, t ...
... current information, methods and models, and to develop an optimal global drilling plan (including drilling, logging and post-cruise science) to address: 1. The minimal/optimal paleomagnetic observations necessary to distinguish whole Earth motion (“true polar wander”) from hotspot drift; that is, t ...
From rifting to oceanic spreading in the Gulf of Aden: a synthesis
... Oligocene, 34–33 Ma ago, rifting started to localise along the future area of continental breakup. Initially guided by the inherited basins, continental rifting then occurred synchronously over the entire gulf before becoming localised on the northern and southern borders of the inherited grabens, i ...
... Oligocene, 34–33 Ma ago, rifting started to localise along the future area of continental breakup. Initially guided by the inherited basins, continental rifting then occurred synchronously over the entire gulf before becoming localised on the northern and southern borders of the inherited grabens, i ...
Lithospheric deformation during the early stages of continental
... that because the mantle material is chemically homogeneous, it is difficult to determine a strict division between the lithosphere and sub-lithospheric mantle. However, to aid in our description of the numerical experiments, we will refer to material initially at <120 km depth and cooler than 1350◦ ...
... that because the mantle material is chemically homogeneous, it is difficult to determine a strict division between the lithosphere and sub-lithospheric mantle. However, to aid in our description of the numerical experiments, we will refer to material initially at <120 km depth and cooler than 1350◦ ...
GIS-based Reconstruction of Pangaea with Recent
... - From a geological viewpoint these inland seas appear to be oceanic crust contained inside continental crust, and it is likely that they were connected to the Panthalassa Ocean by the sea. During the Permian period, about half of the Pangaean continent was under water. □ This study shows that Panga ...
... - From a geological viewpoint these inland seas appear to be oceanic crust contained inside continental crust, and it is likely that they were connected to the Panthalassa Ocean by the sea. During the Permian period, about half of the Pangaean continent was under water. □ This study shows that Panga ...
View/Open - Earth
... of 1040 kg/m3), unconsolidated sediments (density of 1900 kg/m3), evaporites (density 2200 kg/m3) and a 5 km constant thickness crust (density of 2670 kg/m3) limited by and parallel to the base of the evaporites. Grids of bathymetry and sediment thickness were produced at 0.15 km of spatial resolut ...
... of 1040 kg/m3), unconsolidated sediments (density of 1900 kg/m3), evaporites (density 2200 kg/m3) and a 5 km constant thickness crust (density of 2670 kg/m3) limited by and parallel to the base of the evaporites. Grids of bathymetry and sediment thickness were produced at 0.15 km of spatial resolut ...
Garnet: Common Mineral, Uncommonly Useful
... The dark red crystals that frequently adorn common and to its applications in society. Wood, Kiseeva, and Matzen begin with a discussion of the largest reservoir mica schists are garnet (FIG. 1A). The purple-red hue that of garnet in the planet—the mantle—where the mineral sometimes decorates the cr ...
... The dark red crystals that frequently adorn common and to its applications in society. Wood, Kiseeva, and Matzen begin with a discussion of the largest reservoir mica schists are garnet (FIG. 1A). The purple-red hue that of garnet in the planet—the mantle—where the mineral sometimes decorates the cr ...
Geology
Geology (from the Greek γῆ, gē, i.e. ""earth"" and -λoγία, -logia, i.e. ""study of, discourse"") is an earth science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change. Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).Geology gives insight into the history of the Earth by providing the primary evidence for plate tectonics, the evolutionary history of life, and past climates. Geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and for providing insights into past climate change. Geology also plays a role in geotechnical engineering and is a major academic discipline.