Johnny wrote:11,500' is close to the max depth for a modern drillship. I'm not sure they could operate and produce from that depth safely but they can certainly do some good science.
We *do* need a geology thread! Geo-Archaeology anyone?
In the old world at least it's apparent that the geology of the engraved rocks was very important . Engravings incorporate cracks and fissures into the design and often there are naturl marks that resemble cup marks . This can give an impression that the engravers may have considered the the natural markings earlier engravings .
There is also the obviously intentional choice of different qualities and colours of rocks in monuments and the deposition of quartz .
Some reasoning and experiencing the effects of volcanoes may have helped but surely only a very basic understanding if anything would have been the norm in prehistory .