Geology of the Nahe valley
400 million years ago, in the
Devonian period,
Europe was near
the equator and the climate was warm. A shallow ocean with
islands covered central Europe, in which Hunsrück formed a deeper
basin of this ocean with a stable layering of water. The upper
water layers were rich in oxygen and supportive to life, whereas
the lower levels were poor in oxygen and poisoned by hydrogen
sulfide. The remains of living organisms sank into the black mud
and were quickly preserved by ferrous sulphide, which is why they
have kept so well. In the Herrenberg slate quarry near
Bundenbach
a large number of world-renowned fossils were found that, when
x-rayed, showed even the finest details. The rivers that flowed
into the Devonian sea deposited large amounts of muddy sediment,
sand, gravel and clay, which, due to pressure and heat over
millions of years, became layers of stone and rock. In this way,
depending upon the material and coarseness, slate,
sandstone, and (with a high percentage of quartz grains)
Taunus quartzite were created.
300 million years ago, at the end of the
Carboniferous period,
the Devonian layers of the Hunsrück were pushed together by
massive pressure from southeast to northwest creating the
Variszicum mountains (the northern chain). Together with the
Hochwald, Idarwald, and Soonwald chains, a high mountain range
was formed. The debris resulting from the erosion and weathering
of this range was deposited in the basin on the south flank,
building up the "Lower Rotliegende". After another rising of the
mountains and sinking of the basin the process was repeated
creating the "Upper Rotliegende". During the
Permian period
the formation of mountains was accompanied by strong volcanic
activity on the southern fault of Hunsrück.
Photo: View from Ebernburg Castle over the wine village
Ebernburg to the Rotenfels massif.