That is a lovely riddle, and if I solved it, it is almost a shame that you can beat this kind of question to death so quickly with a few min of Googling...
So i venture that it is crater
Lansberg D.
This website gave me that answer - until your question I never knew that "unofficial" names even existed! I love the Internet.
I suppose the crater was named after either
Conrad or Marcel Schlümberger, Alsatian-born geophysicists who happened to found what is today the worlds
largest name in fossil fuel exploration.
I have some fond memories of the name - A (not very well noted) player in unremakable Hertha BSC Berlin football club went by that name (without the umlaut), I think it was in the early eighties. And in Alsace, there is the famous (and also large)
Domaine Schlumberger producing fine Alsatian wines. If you happen to find one, try it. The namesakes of the crater probably hail from that familiy.