Anchiornis's wrist bone was so wedge-shaped that it could fold its arms to its sides, keeping its arm feathers off the ground as it walked.

近鸟龙的腕骨呈深楔形，因此它可以将前肢折叠到身体两侧，行走时前肢上的羽毛可以悬空，不会拖在地面上。

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By decomposing fold and thrust systems into superposed detachment systems, it is possible to simulate extremely complex wedge structures and to do animation of the evolution of the structures.

通过把复杂的褶皱冲断系统分解成一系列迭加的滑脱层系，可以模拟复杂的楔体构造，并提供这些构造演化的二维动画。

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The main kinds of the nappes are sheet thrust, Jurassian fold nappe, wedge-shaped nappe and shearing fold-thrust structure, etc.

其主要类型有席状逆冲构造、侏罗山式褶皱推覆构造、楔状推覆构造及剪切褶皱逆冲构造等。

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