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  • General

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  • 变换板块边界

    Aerial view of the San Andreas Fault in central California, showcasing its geological features.

     

    What does a transform plate boundary look like?
    ::变形板块边界长什么样?

    In the dry part of central California, it looks like this. On one side is the Pacific  Plate . On the other side is the North American Plate. Before  plate tectonics   , people thought the San Andreas was just a  . Now it's known to be a plate boundary!
    ::在加州中部干燥的地方,看起来是这样。一方面是太平洋板块。另一方面是北美板块。在板块构造之前,人们认为圣安德烈亚斯只是一块板块边界。现在人们知道这是一块板块边界!

    Transform Plate Boundaries
    ::变换板板边框

    Two plates may slide past each other in opposite directions. This is called a  transform plate boundary . The plates meet at a  transform fault . As you might imagine, plates do not slide past each other easily. These  plate boundaries  experience massive  . The world’s best known transform fault is the San Andreas Fault in California ( Figure   ). At this fault, the Pacific and North American plates grind past each other. Transform plate boundaries are common as offsets along mid-ocean ridges. They are very small compared to transform faults on land.
    ::两块板块可能会向相反的方向滑过对方。 这叫做变形板块边界。 板块会在一个变形断层处相遇。 正如你可能想象的那样, 板块不会轻易地相互交叉。 这些板块边界经历着巨大的问题。 全世界最著名的变形断层是加利福尼亚州的圣安德烈亚斯断层( Figure ) 。 在这个断层之间,太平洋和北美的板块磨过对方。 变形板块边界在洋中脊的折叠上是常见的。 与陆地断层的变形相比,它们很小。

    Transform plate boundaries are different from the other two types of plate boundaries. At  , new  oceanic crust  is formed. At convergent boundaries, old oceanic crust is destroyed. But at transform plate boundaries,  crust  is neither created nor destroyed.
    ::变形板块的边界不同于其他两种板块的边界。 在egg , 形成了新的海洋地壳。 在egg 汇合的边界上,旧的海洋地壳被摧毁。 但在变形板块的边界上, 地壳既没有被创造也没有被摧毁。

    Map showing the San Andreas Fault with arrows indicating plate movement directions.

     

    The red line is the San Andreas Fault. On the left is the Pacific Plate, which is moving northeast. On the right is the North American Plate, which is moving southwest. The movement of the plates is relative to each other.
    ::红线是圣安德烈亚斯断层。 左边是太平洋板块, 正向东北移动。 右边是北美板块, 正向西南移动。 板块的移动是相对的 。

     

    Summary
    ::摘要

    • At transform plate boundaries, two plates move in opposite direction.
      ::在变形板块边界时,两个板块朝相反方向移动。
    • Transform faults are the site of massive earthquakes.
      ::变形断层是发生大规模地震的地方。
    • The San Andreas Fault is the boundary between the Pacific and North American plates. It is the site of massive earthquakes.
      ::圣安德烈亚斯断层是太平洋和北美板块的边界,是大规模地震的地点。

    Review
    ::回顾

    1. What is the direction of plate motion at a transform plate boundary?
      ::在变形板块边界的板块运动方向是什么?
    1. Why are transform faults prone to massive earthquakes?
      ::为什么转换断层容易发生大规模地震?
    1. Why are earthquakes at the San Andreas Fault so large?
      ::为什么圣安德烈亚斯断层的地震这么大?