Brown Coal Mine
Lignite (Brown Coal) Mine in Schwanenkirchen
How did the lignite evolve?
There are tertiary deposits on the southwestern slopes of the Bavarian Forest and in the Danube Valley from Regensburg to Passau. About 60 million years ago while the Alps were forming at the period of transition from the Mesozoic to Cenozoic ages of the earth, the ground below the level of the present Danube Valley gradually sank. This included the vegetation at that time (plants, alder trees and bald cypress trees and other Mesozoic tree forms), which became covered by ocean water when the area of the Black Sea twice flooded the low areas where the Danube now is.
At the end of the new Cenozoic age the ocean gradually decayed by filling up with settling sediment. The rivers flowing out of the Bavarian Forest and the Alps brought water that transported incredible amounts of rock and stone (especially the River Isar), which covered everything with sand, mud and gravel and thereby, filled up the sea.
The lignite (and the surrounding sedimentation) belong to the field of molasse. In the area of Schwanenkirchen, sedimentation occurred around 18 to 12,8 million years ago, and the lignite was formed out of this underlying organic material. Unfortunately, there has not been an exact examination of the organic content of the Schwanenkirchen brown coal (paleo-botanical), which would allow for more exact dating.