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This is my contribution to this month's Accrectionary Wedge Carnival “Aesthetic Geology”, which is hosted by Geological Musings in the Taconic Mountains. The Lost Geologist beat me to exploiting our field trip about Dimension and Ornamental stones in Berlin, so I had to come up with something else:

(Sorry for the poor quality. I rather hastily scanned a large format reproduction. At least the separate parts aligned, but the colour's a bit poor.)

This is a approx. 16m × 4m mosaic placed on a wall in the hall of the Alfred Bentz Building of the German Federal Institute for Geosciences and Resources (BGR) and shows a idealised cross-section of typical geological features of north-western Germany.

When the Alfred-Bentz-Haus was being planned, it was recognised that the main hall's “pleasant coolness should not be increased to a chilly feeling by a big white area” (Richter-Bernburg 1970). Therefore, a mural was designed by geologist Gerhard Richter-Bernburg and produced by the Franz Mayer'sche Hofkunst-Anstalt (Munich) in the mid 1960s. If possible, they tried to use stones from the corresponding geological units or similar-looking stones. In some cases they had to resort to glass, however. The salts are reproduced by marble.

In the German Geological Yearbook (Richter-Bernburg 1970, with both German and English translations) the designer outlined his thoughts about the mosaic, emphasising that it “should not be an exact geological profile, but that it has to be seen as an ornament, the object of which has some similarity with natural features.”

The mural contains a lot of features, and some (especially deeper) structures undoubtedly may be outdated. Still, it's a nice geological overview.

Separated by a major unconformity running from the lower left to the centre top and again on the far right, we see the strongly folded Basement (“Grundgebirge”, up to the Carboniferous) and the less deformed Covering Formations (“Deckgebirge”). In a few parts, there is also a thin layer of the Cenozoic unconsolidated sediments.

On the right, there is a large intrusion resembling the Mt Brocken pluton of the Harz Mountains.

In the centre, the outcrop of layers dipping to the left (Triassic) depicts their typical cuesta morphology.

On the left, there is a diapir of Zechstein (Upper Permian) salt, including the gypsum cap-rock and the depression caused by subrosion, filled with Tertiary and Quarternary sediments.

To the right of the diapir, basalt lavas have risen along the fractures and built mountains like the Rhön in the Tertiary.

There are a lot of other features, often with a connection to various deposits (oil, gas, ores etc.).

Strangely, there is almost no information about that mosaic to be found. There's a small monograph from 1969 offerd in some old books shops, which I'm quite sure is basically the same as the publication from 1970 I already mentioned. Sadly, the BGR does not even mention the mural on their website. Are they in some way (artistic or geologic) ashamed of it? I don't know.

Richter-Bernburg, Gerhard (1970): Das Mosaik im Alfred-Bentz-Haus, Hannover, ein Ornament als geologisches Dokument / The mosaic in the Alfred-Bentz-Haus, an ornament as a geological document. Geologisches Jahrbuch 88, p. 1–12.