It is difficult to bore and sample the core of rock in soft medium, and it will influence the results of test due to the disturbing of soil and concrete sampling.

在介质软弱的情况下，钻孔取芯、取样很难实现；由于对混凝土芯样、土样产生扰动从而对检测结果产生影响。

youdao

But a new look at Titan's insides reveals even more oddities: Beneath the brittle crust of ice lies a layer of slush. Deeper still is an underground ocean over a solid core of rock and ice.

但最近对泰坦内部的一项新研究却揭开了这颗奇异星球更为怪诞的一面：脆弱的甲烷冰地表之下，覆盖着一层冰泥，更深处依然是一个地下海洋，最中间是冰和岩石并存的固态核心。

youdao

The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.

解释可能是在地球的地幔中，这是在构造板块下面的岩石层，向下延伸超过1800英里到地球铁芯的外边缘。

youdao

First is a core of rock, then clay and lastly soil, topped with grass seed that will withstand being walked on.

BBC: Northumberlandia: The naked lady of Cramlington

The Antarctic Geological Drill (ANDRILL) team, as they're known, has just completed its second field-season here, retrieving an 1, 100-metre core of rock and sediment.

ECONOMIST: The South Pole as location and metaphor

Unlike any other asteroid known today, Vesta has an iron core surrounded by layers of mantle rock and crust, similar to Earth and Mars, preliminary gravity and density measurements suggest.

WSJ: Asteroid Vesta Gets a Close Study