观察剖开的高速公路路基断面我们会发现路基底端的西南部是形成于寒武纪之前的花岗岩,上面覆盖着石灰石。从地质时期起,其他沉积岩,如砂岩和某些生物的海底化石(如腕足类动物和Chrinoid根茎植物)开始沉积于此。再然后,小型文物(这些文物的尺寸与几英里深的地层相比只相当于一英寸甚至更小)便出现了。总体规律是在史前文明后才出 Observe the section of freeway embankment. We will find that the southwestern part of the bottom of the embankment is granite that was formed before the Cambrian and covered with limestone. Since the geologic period, other sedimentary rocks, such as sandstone and certain marine fossils (eg, Brachiopods and Chrinoid rhizomes) began to be deposited here. Then again, small artifacts, the dimensions of which are only one inch or less in comparison to a few miles deep, are emerging. The general rule came after prehistoric civilization