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Carboniferous and Devonian carbonate rocks are present in the subsurface of the Weisweiler lignite-fired power plant near Aachen, Germany. The utilisation of these rocks for the purpose of deep geothermal energy extraction using hydrothermal techniques is currently being explored. First steps are undertaken as green field exploration in the course of the transnational EU-Interreg-funded ""Roll-out of Deep Geothermal Energy in North-West Europe"" (DGE-ROLLOUT) project, which aims to provide solutions to reduce carbon-dioxide emissions using a variety of geoscientific approaches. As a result of multiphase deformation and faulting through Variscan and Alpine (post-)orogenic processes, a complex geological setting has emerged in the Weisweiler subsurface. However, considering the formation of both syncline-anticline and horst-graben structures the geological setting appears to exhibit favourable conditions for deep geothermal exploitation at several depth levels. Besides ongoing mapping campaigns, as well as lithological and structural studies, a preliminary geological 3D model of the subsurface of the Weisweiler area has been constructed on the basis of which a first drilling operation is currently being planned. At the same time, the subsurface 3D model is currently being transferred into a thermohydraulic 3D model to obtain first impressions on possible fluid pathways within the targeted carbonate horizons. In addition, a variety of petrophysical and (isotope) geochemical analyses of analogue rock samples are also underway.

The regional and stratigraphic subdivision of the Tertiary as part of the Stratigraphic Table of Germany 2016 (STD 2016) is summarised. Primarily, changes compared to STD 2002 are commented. Concerning more detailed explanations, the reader is referred to the respective literature and corresponding definitions in LithoLex (https://litholex.bgr.de). The STD 2016 has not only practical significance, but is also a working basis for (1) the further development of the stratigraphic terminology of the German Tertiary, (2) the correlations of regional units and (3) an improved correlation of the regional stages of the North Sea Basin and the Central Paratethys with the Global Stratigraphic Scale.

Devonian and Carboniferous carbonate rocks are present in the subsurface of the Weisweiler lignite-fired power plant near Aachen, Germany. The utilisation of these rocks for deep geothermal energy extraction is currently being explored within the scope of the transnational EU-INTERREG-funded “Roll-out of Deep Geothermal Energy in North-West Europe (DGE-ROLLOUT)” project, which aims to provide solutions to reduce carbon-dioxide emissions using a variety of geoscientific approaches.Marine transgressive-regressive cycles during mid-Palaeozoic times enabled the formation of extensive reef complexes on the southerly continental shelf of the Laurussian palaeocontinent. Supported by favourable climatic conditions including warm, clear and shallow waters, the Givetian to Frasnian Massenkalk facies and the Dinantian Kohlenkalk Group, each several hundred meters thick, were deposited in North-West Europe.In the Weisweiler area, these Palaeozoic carbonate rocks were covered by voluminous paralic sedimentary rocks and deformed to large-scale, generally northeast-southwest-trending, syncline-anticline structures during the Variscan Orogeny. Alpine (post-)orogenic processes further induced faulting, resulting in fault-block tectonics in the Lower Rhine Embayment area of tectonic subsidence. Significant multiphase karstification of the Palaeozoic carbonate rocks, which can be observed in nearby exposed counterparts, supports their enhanced geothermal exploitation potential.3D-modelling of the depths and dimensions of the Weisweiler subsurface carbonate reservoirs is carried out using the commercial software Move [v2019.1.0; Petroleum Experts Ltd], and is constrained by lithostratigraphic data obtained from drilling operations, geological mapping, and interpretation of seismic profiles. The 3D-model exhibits a complex geotectonic environment, including the development of both parasitic folds and thrust faults prior to the generation of Tertiary fault-block tectonics. The depths of the tops of the reservoirs are estimated to c. 1,200 m for the Carboniferous and to c. 2,000 m for the Devonian carbonate rocks, taking into account typical thicknesses of the overlying and underlying strata. Considering possible tectonic repetition below the thrust faults, the reservoir rocks may also occur significantly deeper in the subsurface. The 3D-model is currently being transformed into a HeatFlow3D [DMT GmbH & Co. KG] / Petrel [v2017; Schlumberger N.V.] model in order to approximate the fluid circulation and pathways within the carbonate reservoirs.Based on the current model, a target area for 2D-seismic surveys and a c. 1,000 to 1,500 m deep exploration borehole have been selected. These investigations will commence in the summer of 2020, and will then enable geochemical and petrophysical investigations of the Palaeozoic rocks. The possibility of deep geothermal energy extraction from the Weisweiler subsurface and subsequent evaluation of the transition of the conventional lignite-fired power plant towards its utilisation of renewable “green” energy is carried out in close collaboration with DMT GmbH & Co. KG, Fraunhofer Institute for Energy Infrastructures and Geothermal Energy and RWE Power AG, all partners within the DGE-ROLLOUT project. The successful realisation of this project may serve as a pilot for similar projects considering the forthcoming fossil fuel phase-out.

In regions of low strain, long earthquake recurrence intervals (104–106 yrs) and erosive processes limit preservation of Quaternary markers suitable for distinguishing whether faults slip at uniform or secularly varying rates. The Lower Rhine graben in the border region of Germany, The Netherlands, and Belgium provides a unique opportunity to explore Quaternary slip‐rate variations in a region of low strain using the basal (2.29±0.29 Ma) and surface (700±80 ka) contacts of the regionally extensive main terrace (“Hauptterrasse”), deposited by the Rhine and Maas Rivers. These surfaces are vertically offset 3–140 m and 0–68 m, respectively, across individual fault strands within a distributed network of northwest‐trending, slow‐slipping ( 80% of the sites record an apparent increase in slip rate for the more recent interval from 700 ka to present, which corresponds to a period of increased uplift of the nearby Rhenish Massif and regional volcanism. However, the apparent increase in slip rate could result, in part, from erosion of the footwall surface below the main terrace, leading to an apparent displacement that is smaller than the total vertical offset since the start of the Quaternary. Prior work focused on characterization of these faults as seismic sources in the Lower Rhine graben has preferentially relied on the average fault‐slip rate constrained using the base of the main terrace. We suggest that average fault‐slip rates calculated using the ∼700 ka main terrace surface are subjected to fewer uncertainties and sample a time interval that is more relevant for seismic‐hazard analysis. [Electronic Supplement:][1] Table of main terrace surface and basal contact offset measurements, figure describing an unrealistic faulting scenario, and a KML file with the fault‐trace mapping spanning the Lower Rhine graben. [1]: http://www.bssaonline.org/lookup/suppl/doi:10.1785/0120160197/-/DC1

Die in der Stratigraphischen Tabelle von Deutschland 2016 (STD 2016) verwendete Zeitskala beruht mit kleinen Modifikationen auf den Komposit-Altern der Stratigraphischen Tabelle von Deutschland 2002 (STD 2002). Sie differiert von der ,,Geological Time Scale 2012" (GTS 2012). Die geochronologischen Einheiten zeigen auch die westeuropäischen Regionalstufen; die traditionelle deutsche Kulm-Gliederung wurde nicht mehr übernommen. Abfolgen des Mississippiums (unteres Karbon) sind in den deutschen Mittelgebirgen und im Untergrund Norddeutschlands weit verbreitet. Paralische Abfolgen des Pennsylvaniums (oberes Karbon) kommen übertage in der subvariszischen Saumsenke zwischen Aachen und Osnabrück sowie im Untergrund Norddeutschlands vor. Bis auf wenige Ausnahmen im Pennsylvanium einset- zende intramontane Abfolgen sind aus mehreren, zum Teil ausgedehnten Becken in Südwest- und Mitteldeutschland über- und untertage bekannt. Die vielgestaltige Fazies des deutschen Karbons wird von der nach Nordwesten progradierenden variszischen Orogenese und deren Ende im späten Westfalium gesteuert. Die Fazies reicht von Beckensedimenten und Flyschablagerungen sowie lateral anschließenden Plattformkalken im Mississippium (,,Kulm-Fazies" bzw. ,,Kohlenkalk- Fazies") zu paralischen und intramontanen, fast ausschließlich pennsylvanischen Molasse-Ablagerungen. Gegenüber der STD 2002 wurden die traditionellen Namen in den Standard-Profilen des Mississippiums von Aachen, Velbert und des Sauerlandes durch neue Formationsbezeichnungen ersetzt. Neu ist auch die Untergliederung des nordöstlichen und östlichen Rheinischen Schiefergebirges (Kellerwald, Lahn-Dill-Gebiet), wo durch Zirkon-Provenienz-Analysen rhenoherzynische und armorikanische Decken unterschieden wurden. Das Mississippium des Thüringisch-Vogtländischen Schiefergebirges und des Frankenwaldes wurde stärker differenziert und mit Formationsnamen belegt. Kleinere Änderungen gab es im Namurium der subvariszischen Saumsenke am NW-Rand des Rheinischen Schiefergebirges und in den intramontanen Pennsylvanium-Abfolgen der mitteldeutschen Becken. The Carboniferous timescale in the Stratigraphic Table of Germany 2016 (STD 2016) relies on slightly modified composite ages already used in the Stratigraphic Table of Germany 2002 (STD 2002). They differ from the Geological Time Scale 2012 (GTS 2012). Besides the international stages, the western European Mississippian regional stages are shown. The traditional German subdivision of the Kulm was discarded. Mississippian (lower Carboniferous) sedimentary successions are widespread in the mountainous regions and hills in the central part of Germany (Rhenish Mountains, Harz, Thuringian Forest, Franconian Forest and adjoining regions of Saxony). They are also widespread in the subsurface of Northern Germany. Paralic Pennsylvanian (upper Carboniferous) successions crop out in the Subvariscan Basin between Aachen and Osnabrück, and continue into the subsurface of Northern Germany. Intramontane successions, with few exceptions starting in the Pennsylvanian, occur in several, in part extended basins in southwestern and central Germany. They are known from outcrop and subsurface. The diversified facies of the Carboniferous in Germany is controlled by the northwestern progradation of the Variscan Orogeny and its finalisation during the late Westphalian. During the Mississippian, megafacies realms include deeper water basinal sediments and flysch deposits, and laterally adjoining shallow-water platform carbonates ("Kulm facies" and "Carboniferous Limestone facies", respectively). Locally starting in the later Mississippian (upper Viséan), paralic and purely continental intramontane molasse deposits prevail during the Pennsylvanian. The traditional lithostratigraphic terms of the Mississippian regional standard profiles of Aachen and the western and northern Rhenish Mountains (Velbert, Sauerland) were completely substituted by new formations. Lithostratigraphic terms of the northeastern and eastern Rhenish Mountains (Kellerwald, Lahn-Dill area) were completely revised, as provenance analyses of detrital zircons enabled the differentiation of Rhenohercynian and Armorican nappes. Also the Mississippian of the ThüringischFränkisches Schiefergebirge and the Frankenwald (Franconian Forest) are better differentiated; formations were introduced for most lithostratigraphic units. Minor modifications concern the Namurian of the Subvariscan Basin at the northwestern border of the Rhenish Mountains and the intramontane Pennsylvanian successions of several basins in central Germany.

In his paper “How Auctions Work for Wine and Art” (1989), Orley Ashenfelter shows how auctioneers provide genuine expertise in predicting prices of art at auction. Using material from British and American auctions of impressionist paintings, he is able to show a high correlation of price estimates and prices actually obtained.