German to English Tech/Engineering Mining & Minerals / Gems geological sediment formations

Good Friday evening! Here is a geological distinction that I simply cannot figure out. Sorry if this should be two questions, but since the basic difficulty is a distinction, I've put them together.

Same context as previous recent post relating to this mining project, we're now in the "Geological Situation" area of a General Plan of Operation for a gravel sand opencast mine.

"Das Liegende der nutzbaren Sedimente wird vom Saale 2 - Geschiebemergel gebildet. Im Hangenden wird die Rinnenstruktur von der Grundmoräne des Mecklenburger Stadiums überlagert."

Saale 2 Geschiebemergel is till [glacial sediment] from the Saale glacial period. I don't know the distinction between Hangende and Liegende, but it likely has to do with a vertical or horizontal orientation of the sediment bands. Any help appreciated

Thanks in advance