They found fossils of microscopic marine plants which suggest that the region was once open ocean, not solid ice.

他们发现了微型海洋植物的化石，表明该地区曾经是开放的海洋，而不是坚固的冰层。

youdao

Within samples collected from the solid substances lying beneath the ice they found fossils of microscopic marine plants which suggest that the region was once open ocean not solid ice.

在从冰下的固体物质中收集的样本中，他们发现微型海洋植物的化石，这表明这个区域曾经是开阔的海洋而不是坚硬的冰。

youdao

The cutlery is plate, not solid silver.

这套餐具是镀银的，不是纯银的。

《牛津词典》

At times like these, we remember that the ground is not as solid and unchanging as people might like to think.

VOA: special.2010.01.12

Les Paul was not the only person to make a solid-body guitar.

VOA: special.2009.09.27

Making a guitar with a solid body permitted the sound of the strings to last longer because their vibrating energy was not weakened by a vibrating sound box.

VOA: special.2009.09.27

My point here is that tolerance is very tricky business, and probably not solid grounds for dismissal by itself.

FORBES: How Much Of Our Personal Lives Should Be Under Employer Surveillance?

Its cherry veneer, framed with maple, is decorated with porcupine quillwork, more conventionally used to embellish hides or birch bark, not solid wood.

WSJ: Changing Hands | We Are Here! | Native, North American, New | By Lee Rosenbaum

And the rating agencies, which are meant to be supervised by the SEC, were free to get paid for putting their highest imprimatur on deals that were simply not solid.

FORBES: The Blame Game