1·Beneath the Sahara are huge aquifers, basically a sea of fresh water, that's perhaps a million years old filtered through rock layers.
撒哈拉沙漠下面是巨大的含水层，基本上是一片淡水的海洋，那可能是经过岩石层过滤的，已经有一百万年历史。
2·A borehole image of rock layers indicating an underground point bar.
指示某地下曲流沙坝的一幅岩层钻孔图像。
3·The canyon's rock layers display a geological history some two billion years old.
峡谷岩石的层次显示了它约有20亿年的历史。
4·They said that there was likely to be oil in the crests of folds of rock layers.
他们认为在岩层褶皱的顶部可能会有石油。
5·Separate rock layers, or plates, under the oceans and continents move very slowly.
海洋和陆地下面的岩石层或板块在缓慢地运动。
6·The warning signs show the weakness of rock layers that can precede an earthquake.
警示牌显示前方岩石脆弱预示可能会发生一次地震。
7·Sedimentary rock layers are always characterized by a particular seismic response.
沉积岩地区，总是以一种独特的地震响应为特征的。
8·The continuous play of sun and shadow on the rock layers creates an awesome display.
太阳和影子在岩石层上不断地上演着好戏。
9·The sounds bounce off rock layers below the sea floor and are picked up by the phones.
声波从海底之下的岩层反射回来并由检波器接收。
10·Softer rock layers within the mesas eroded to form steep canyons and overhangs along their slopes.
台地被风化侵蚀后的沙土层形成了陡峭的峡谷和悬崖。