Geländeseminar Breinig nach Vicht
Recently we promoted the Lehmjöres hike around Stolberg-Vicht on WDR TV. The village Vicht is located 2 km south of Stolberg and 5 km ESE Aachen and stretches along the river Vicht. It not only displays the strong relation of geology and industry development, but is the origin of Germany’s industrial culture, which from the Aachen-Stolberg region later moved to the Ruhr area and established the Ruhr district, Europe’s largest industrial center.
Geology
Vicht exposes yellowish Devonian carbonate rocks containing reef building stromatopores to the north, which are often used as bricks for buildings. A road cut exposes corals (cyatphyllum quadrigenium) in the quadrigenium formation in the footwall. Even older rocks can be found in siltstones along a footpath with Taeniocrada, which are remnants of a plant growing in low water. It contributed to the greatest oxygenation event in earth history which occured 400 Mio year ago (Emsian) and reflects the diversification of plants. These primitive plants by then spread from sea on land and greened the continents. They increased the oxygen content close to today’s of 21% while carbon dioxide was at app 0.3-0.4% (before industrial revolution it was app 275 ppm and now rised to app 375 ppm = 0.0375%). Hard matrix-supported conglomerates cross the village, their rough surfaces indicate sandblasting by desert storms. The age of this Vicht formation is Eifelium. These red colored, hard rocks of former wadi-type sediments are not only used as building bricks for houses but also for iron smelters in the valley. The rock bedding is now vertical at the most prominent exposure Kluckensteine, showing that the region was affected by plate tectonics. Rocks were bended and folded upright during the Variscan mountain formation in the Upper Carboniferous. Iron was mined only on the top of the surrounding hills, which was concentrated by weathering on a former peneplain in Tertiary times. Further on the Lehmjoeres hike, carbonate rocks host lead and zinc deposits and can be studied between the villages Vicht and Breinig around the Schlangenberg. Yellow Galmei violets indicate the high lead-zinc content of soil, and round holes (Pingen) point to the old mining activities. Ores deposited in the middle Devonian and lower Carboniferous carbonate rocks during extension in Jurassic and Cretaceous times.
Industry
Since medieval times the region was the center of iron production, with energy provided by charcoal from the surrounding woods of the Eifel, and further energy for air streams from the river mills. The river Vicht divided the property of the abbey of Kornelimuenster (founded in 814AC) from the duchy of Juelich (a state of in the Holy Roman empire from the 11th to 18th century) to the east. Because of better taxes and less religious restrictions, medieval iron smelters and production settled only on the eastern side of the stream. Many iron production plants were owned by the Hoesch family since medieval times, some still preserved. The family moved to the Ruhr area in the 19th century following the upcoming hard coal mining. The established Hoesch AG focused on steel and mining in the Ruhr district and Siegerland. It was taken over by Krupp AG, which later was merged to become ThyssenKrupp AG. Thyssen’s founder August also originated from the region, where his father Friedrich Thyssen managed Germany’s first wire rod factory in Aachen in the 19th century. Lead-zinc mining started before Roman times and continued until the 20th century. The region still hosts one of the world’s largest lead smelters, and is known as the world’s first brass district starting in the 16th century. While the zinc was derived locally in the Stolberg-Kelmis region, copper was imported from Mansfeld, Saxony-Anhalt. The copper yards (Kupferhoefe) established in Stolberg from 1575 onwards point to the importance of copper, the evaluation of the grade and the right mixture to make brass.