* *大陆地壳* *形式,因为持续的火山岩浆流和压力,需要在一段时间内的侵蚀数百数百万年天气完全一些对象。一起,构造板块相互冲撞形成大陆地壳和陆地上建筑(喜马拉雅山是一个为例)>与海洋地壳,大陆地壳是由板块构造。在汇聚板块边界,构造板块相互撞击,大陆地壳推力造山运动的过程中,或造山。出于这个原因,大陆地壳最厚的部分是在世界上最高的山脉。像冰山一样,高大的山峰喜马拉雅山脉和安第斯山脉只是部分地区的大陆州大洋地壳延伸不均低于地球以及飙升到大气中。>“壳”描述了类地行星的外层。我们星球的薄,40公里(25英里)深地壳地球上1%的mass-contains宇宙中所有已知的生命。>地球有三层:地壳、地幔和核心。地壳是由固体岩石和矿物。在地壳地幔之下,也主要是固体岩石和矿物,但被韧性半固态岩浆的地方。 At the center of the Earth is a hot, dense metal core. > Earth’s layers constantly interact with each other, and the crust and upper portion of the mantle are part of a single geologic unit called the lithosphere. The lithosphere’s depth varies, and the Mohorovicic discontinuity (the Moho)—the boundary between the mantle and crust—does not exist at a uniform depth. Isostasy describes the physical, chemical, and mechanical differences between the mantle and crust that allow the crust to “float” on the more malleable mantle. Not all regions of Earth are balanced in isostatic equilibrium. Isostatic equilibrium depends on the density and thickness of the crust, and the dynamic forces at work in the mantle. > Just as the depth of the crust varies, so does its temperature. The upper crust withstands the ambient temperature of the atmosphere or ocean—hot in arid deserts and freezing in ocean trenches. Near the Moho, the temperature of the crust ranges from 200° Celsius (392° Fahrenheit) to 400° Celsius (752° Fahrenheit). > Crafting the Crust > Billions of years ago, the planetary blob that would become the Earth started out as a hot, viscous ball of rock. The heaviest material, mostly iron and nickel, sank to the center of the new planet and became its core. The molten material that surrounded the core was the early mantle. > Over millions of years, the mantle cooled. Water trapped inside minerals erupted with lava, a process called “outgassing.” As more water was outgassed, the mantle solidified. Materials that initially stayed in their liquid phase during this process, called “incompatible elements,” ultimately became Earth’s brittle crust.