In most localities a given species of clam or coral persists essentially unchanged throughout a thick formation of rock, only to be replaced suddenly by a new and different species.

在大多数地方，某一种蛤蜊或珊瑚在厚厚的岩层中保持基本不变，只是突然被一个新的不同的物种所取代。

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The rock assemblages of the Bayinbuluke formation are mainly alkaline basalt - thick andesite - alkaline rhyolite.

火山岩岩石组合以碱性玄武岩-粗安岩-碱性流纹岩为主。

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A contagious bacterial skin infection, usually of children, that is characterized by the eruption of superficial pustules and the formation of thick yellow crusts, commonly on the face.

脓疱病一种儿童常患的传染性皮肤细菌感染，其特征为表皮小脓疱的发作和黄色厚的硬皮的形成，通常出现在脸部。

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Think about what this advancement has meant just in terms of access to the resources: When drilling into a hydrocarbon bearing formation 100 feet thick, vertical drilling would allow an operator to contact 100 feet of rock, which would limit your potential recovery to whatever oil or gas would flow into that length of pipe.

FORBES: Horizontal Drilling: A Technological Marvel Ignored

About 14 million years ago, a period of climate change caused the formation of the Antarctic ice sheet, which averages one mile in thickness and gets up to three miles thick in some parts.

BBC: How Antarctica works