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Historical Note on Earthquakes
Published in Santiago Pujol, Ayhan Irfanoglu, Aishwarya Puranam, Drift-Driven Design of Buildings, 2022
Santiago Pujol, Ayhan Irfanoglu, Aishwarya Puranam
The mantle, the layer under the crust, is approximately 2,900 km thick (Figure 17.2). The specific gravity of the mantle is said to vary from 3.2 at the boundary with the crust to near 6 at its boundary with the core (Figure 17.3). The temperature in the mantle is very high. At a depth of 100 km, the temperature can be over 1,500°C in young oceanic crust but approximately half that much in the Precambrian shield (old crust). Under most tectonic zones, the mantle melts at a depth of 1,200–1,400 km creating a zone of low seismic velocity. Under continental shields, the temperature rises slowly and may not lead to melting of the mantle.
Nuclear and Hydro Power
Published in Anco S. Blazev, Energy Security for The 21st Century, 2021
It took over 2 billion years to go through the: Formation of oceanic crust and lithosphere through melting of the mantle at mid-ocean ridges,Migration of the oceanic lithosphere laterally to a site of plate consumption (this is marked at the surface by a deep-sea trench),Production of fluids and magmas from the down-going (subducted) lithospheric plate and overriding mantle “wedge” in these subduction zones,Transfer of these fluids/melts to the surface in zones of “island arcs” (such as the Pacific’s Ring of Fire),Production of continental crust from the island arc protoliths, through re-melting, granite formation and intra-crustal recycling.In nature, uranium ore is found as uranium-238 (99.27%), uranium-235 (0.72%), and a very small amount of uranium-234 (0.006%).
The Other Energy Markets
Published in Anco S. Blazev, Global Energy Market Trends, 2021
It took over 2 billion years to go through the: Formation of oceanic crust and lithosphere through melting of the mantle at mid-ocean ridges,Migration of the oceanic lithosphere laterally to a site of plate consumption (this is marked at the surface by a deep-sea trench),Production of fluids and magmas from the down-going (subducted) lithospheric plate and overriding mantle “wedge” in these subduction zones,Transfer of these fluids/melts to the surface in zones of “island arcs” (such as the Pacific’s Ring of Fire),Production of continental crust from the island arc protoliths, through re-melting, granite formation and intracrustal recycling.In nature, uranium ore is found as uranium-238 (99.27%), uranium-235 (0.72%), and a very small amount of uranium-234 (0.006%).
Scientific ocean drilling in the Australasian region: a review
Published in Australian Journal of Earth Sciences, 2022
The floors of the oceans are intrinsically important in terms of understanding our planet’s most extensive crustal type on time-scales of ca 100 million years. The oceanic crust is predominantly formed by igneous activity, and together with the underlying lithosphere, it is recycled back into the Earth’s mantle. Dispersal and accretion of continental masses accompanies this crust-forming and destruction process. The oceans and seas are also the repository of sediments derived from continents and the remains of biological activity in the oceans that are modulated by the coupled changes in ocean–atmosphere systems. This provides an overview of results arising from coring the floors of the oceans and seas of the world by international scientific ocean drilling, driven by the importance of this vast realm to our planet.
Suitability of Icelandic basalt for production of continuous fibres
Published in Applied Earth Science, 2019
Birgir Johannesson, Thorsteinn I. Sigfusson, Hjalti Franzson
Basalt is the most common rock on the surface of the planet and is the dominant component of oceanic crust, as well as of many mid-oceanic islands, including Hawaii and Iceland (e.g. Klein and Philpotts 2015). Utilisation of basalt has been developed for several industrial applications such as in the building industry and highway engineering (e.g. Morozov et al. 2001; Singha 2012; Pisciotta et al. 2014). Basalt has also been used in casting processes to make tiles and slabs for architectural applications, and cast basalt tubes have been used in industrial applications because of its high abrasion resistance. The concept of using molten rock to form fibres dates from the 1920s and the production of basalt rock wool is a well-known industrial product. However, serious research work to develop continuous basalt fibres (CBF) began in the 1960s, principally undertaken in former Soviet countries and the U.S.A. (Ross 2006).
Subduction geometry controls on dynamic topography: implications for the Jurassic Surat Basin
Published in Australian Journal of Earth Sciences, 2019
T. Smith, V. Bianchi, F. A. Capitanio
The subducting oceanic slab component is partially immersed in the mantle in a manner similar to an active subduction zone, and has dimensions of approximately 1300 km wide, 100 km thick (representing an approximately 140 My oceanic crust and underlying lithospheric mantle) and 1500 km long. The subducted portion of the slab has a dip of ∼40°, as per estimations of the dip angle of subduction zones in Matthews, Hale, Gurnis, Müller, and DiCaprio (2011). A continental crustal layer was added above the upper mantle unit in all models to provide realistic pressures of an overriding plate on the upper mantle. The continental layer is located adjacent to the oceanic slab and has dimensions of 1300 km × 100 km × 1000 km in the x, y and z axes, respectively. Densities of the modelled crusts are 2750 kg/m3 for the continental and 3300 kg/m3 for the oceanic crust, whereas the viscosity used was 1.0 × 1022 Pa.s, for all crust types. A generalised Andean-style subduction zone model based on Stegman et al. (2010) was used as a control model (Figure 5a).