Excursions

GeoMin2026 – pre- and post-conference excursions – overview

Pre-excursions (Sunday, 20.09.2026)

1) The Coal-bearing Upper Carboniferous – Iconic Outcrops and Coal Mining History of the Southern Ruhr Area

This field trip explores the coal-bearing Upper Carboniferous of the Ruhr Valley, with a focus on stratigraphy, sedimentology, and coal mining. Participants will visit classic outcrops of supra-regional importance, as well as the visitor´s mine Nachtigall. All stops are located in Bochum and its surroundings, where former quarries provide exceptional exposure of the coal-bearing successions.

 

• Guide(s): Dr. Till Kasielke & Dr. Volker Wrede (GeoPark Ruhrgebiet)
• Duration: full-day
• Number of places: max. 25

 

2) Basin development in the northern foreland of the Variscan Orogen

This field trip offers insights into the sedimentary and tectonic development of the northern foreland of the Variscan Orogen from the latest Devonian to the Carboniferous. We will visit illustrative geotopes, active quarries, and classic fossil sites of the northern Rhenish Massif. The sedimentary record encompasses the Devonian-Carboniferous boundary, the Rhenish Kulm Basin sediments, and the transition to the intensively mined coal-bearing succession of the Ruhr Basin.

 

• Guide: Dr. Sascha Sandmann (Geologischer Dienst NRW)
• Duration: full-day
• Number of places: max. 25

 

3) A look into a sediment-stressed Devonian reef (Klutert Cave, Ennepetal)

The Klutert Cave is the main cave of the Klutert-Cave system that is located ca. 30 minutes south of Bochum. Thanks to a recent, intensive cleaning of the cave walls by the Arbeitskreis Kluterthöhle, the cave enables a unique three-dimensional insight into the facies architecture of the lower coral limestone member (auto- to autoparabiostrome; ca. 12 m thickness) of the upper Honsel formation (Middle Devonian). Minute details of the internal organisation of the reef that has formed under high sediment influx, its burial and the reef builders are accessible.

 

• Guide: Dr. Tanja Unger (Heidelberg University)
• Duration: half-day
• Number of places: max. 20

 

Post-excursions (Friday, 25.09.2026)

4) From reefs to mountains, geothermal reservoirs and caves – Devonian Massenkalk carbonates at the northern Rhenish Massif as geological archives

This field trip explores the geological history of the Devonian Massenkalk limestones from their deposition in a shallow marine environment to a world-class archive for tectonic and diagenetic events between the Variscan Orogeny and the Recent. We will first visit Steltenberg quarry (Hohenlimburger Kalkwerke, Hagen Hohenlimburg), which has been explored as a surface analogue for deep geothermal carbonate reservoirs in recent years due to its complex post-depositional overprint. As this locality is known for its variety of minerals, there will be an opportunity to collect rocks in the field. Afterwards, we will head over to Dechen Cave (visitor cave in Iserlohn). Dechen cave is located in an area that hosts several of North Rhine-Westphalia´s longest cave systems. We will have a tour through the visitor cave to learn about cave formation and its archive potential.

 

• Guide: Dr. Mathias Müller (Ruhr University Bochum)
• Duration: full-day
• Number of places: max. 25

 

5) Blast from the Past? Peat, oil, and gas extraction in the Grafschaft Bentheim.

Energy resources have always been extracted in the Grafschaft Bentheim and neighbouring regions; first peat, then oil and gas. The excursion follows in the footsteps of energy resource extraction and visits production sites, renaturalised landscapes, and the reservoir rock used for oil extraction.

 

• Guide: Prof. Dr. Tobias Backers (Ruhr University Bochum)
• Duration: full-day
• Number of places: max. 26

 

6) Tracing the Ice Ages in the Lower Rhine Embayment

This field trip traces the imprint of the Ice Ages on the landscapes of the Lower Rhine Embayment and the Rhine–Ruhr region. Participants will examine characteristic landforms and sediments, including terminal moraines and extensive river terraces, as key archives of Quaternary environmental change. Field observations provide insight into past climates and the glacial and periglacial processes that shaped the region.

 

• Guide(s): Prof. Dr. Melanie Kranz (RUB) and Dr. Till Kasielke (GeoPark Ruhrgebiet)
• Duration: full-day
• Number of places: max. 25