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Petroleum Pre-Period
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Temperature and pressure both modify the minerals’ crystal structural forms. The earth’s mineral materials exist in solid as well as in liquid forms because of temperature and pressure effects. Temperature and pressure increase with depth but not uniformly. The temperature gradient in the crust is 10–50°C/km. The average temperature gradient of the earth is 30°C/km. In deeper zones the temperature gradient is much higher. The crust is made of heterogeneous solid minerals. The upper mantle is in a mixed solid/plastic state. This is because different layers of minerals have different melting points. The temperature ranges from 300 to 900°C at the boundary between the crust and mantle. The temperature is as high as 4000°C at the border of the lower mantle and outer core. The outer core contains mainly Fe–Ni alloy in a liquid state because of high temperatures. The temperature between the inner and outer core boundary is 5400°C. The inner core of the earth is a solid state of dominant Fe–Ni alloy. Deep inside the inner core the temperature is as high as 7000°C.
The Origin of the Elements and Earth
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Today we have a layered Earth akin to a hard-boiled egg (Fig. 1.25). The crust (egg shell) averages 30–50 kilometers (20–30 miles) thick in continental regions and 5–10 kilometers (3–6 miles) in oceanic regions. It is composed primarily of silicate rocks and minerals. The mantle (egg white) averages about 2900 kilometers (1800 miles) thick and accounts for 84% of Earth’s volume. It is mostly solid, but on a geological time scale it flows like a very viscous liquid. Like the crust, the mantle is composed mostly of silicates, but it contains less silicon and oxygen than the crust. The core (egg yolk) extends from the center to about 3480 kilometers (2100 miles). It is mostly iron (80%) and nickel (19%). The inner core is solid, and the outer core is molten.
Introduction
Published in Fang Lin Luo, Hong Ye, Renewable Energy Systems, 2013
The Earth’s outer surface is divided into several rigid segments, or tectonic plates, that migrate across the surface over periods of many millions of years. About 71% of the surface is covered by salt water oceans, with the remainder consisting of continents and islands, which together have many lakes and other sources of water that contribute to the hydrosphere. Liquid water, necessary for all known life, is not known to exist in equilibrium on any other planet’s surface. The Earth’s poles are mostly covered with solid ice (Antarctic ice sheet) or sea ice (Arctic ice cap). The planet’s interior remains active, with a thick layer of relatively solid mantle, a liquid outer core that generates a magnetic field, and a solid iron inner core.
Numerical investigation of collision between massive ice floe and marine structure using coupled SPH-FEM method
Published in Ships and Offshore Structures, 2023
Yan Feng, Hui Li, Muk Chen Ong, Weiwei Wang
In this study, the technology framework of the fluid (water)-solid (ice and structure) interaction model is shown in Figure 1. First, the consolidation coupled model is prospectively implemented to simulate the massive ice floe. The coupled SPH-FEM model of ice consists of SPs for the outer layer and solid elements for the inner core. There are some advantages considering the outer layer of SPH surrounding the inner FEM: Suppose the particle portion of the ice model is restricted to outer collision regions that are severely deformed; the coupled SPH-FEM model represents less required computational time than the SPH model and is more accurate than the FEM model. The density and pressure differences exist between the outer particle layer of the ice model and the SPs of water, which cause particle motion and provide buoyancy for the massive ice floe. Therefore, the difficulties in achieving the interaction between ice and water are fewer than the coupling defined by the contact algorithm. Second, the contact coupled method is used to simulate the contact process between the massive ice floe and the marine structure. Besides, the hydrodynamic effect of the SPH water on the FEM structure is guaranteed.
On magnetostrophic dynamos in annular cores
Published in Geophysical & Astrophysical Fluid Dynamics, 2020
Paul H. Roberts, Cheng-Chin Wu
In the main text, we have modelled the inner core as a solid of the same electrical conductivity as the surrounding fluid. If instead we modelled it as an insulator, would be zero in and would be a linear combination (19a) of the interior solutions of Laplace's equation: Conditions (30c–e) would require, as in (21d,e), This defines uniquely on and therefore throughout .
Pressure-dependent nonlinear optical properties in a group III–V/II–VI core/shell quantum dot
Published in Phase Transitions, 2020
M. Elamathi, A. John Peter, Chang Woo Lee
An exciton confined in an InP quantum dot with a spherical potential barrier (ZnS) is considered with the confining potential which is assumed to be zero inside and V outside. In this model, is referred as the inner core radius related with the InP material and the outer shell radius corresponds to ZnS material in the core/shell quantum dot. The conduction and valence bands are centred around valley of InP and ZnS core/shell structure. The Schrödinger equation for the exciton is expressed as