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After a recent breakthrough discovery of shatter cones in the Ries Crater there was another finding from a different lithology in 2022. Within a block of the Bunte Breccia in the Aumühle suevite quarry consisting of claystone of the Lower Jurassic Amaltheenton Formation (upper Pliensbachian), ballistically transported to the crater rim, some more specimens were discovered and are reported here. The new findings help to understand the shock effects on the different lithologies and the block pattern of the Bunte Breccia.

After decades of research in the Ries crater with only few findings of limestone shatter cones the situation changed with the discovery of a new hotspot within the Bunte Breccia close to the northern crater rim. The new Ries shatter cones originate from pedogenetically transformed carbonates within clay beds of the Middle Keuper sandstone section, most probably from the one at the base of the Lower Burgsandstein. Together with additional findings they suggest a scenario of a fan-like ejection of blocks with dimensions of some 50 to 100 m. They were excavated from about 300 m depth inside the transient crater and transported ballistically more than 6 km towards the north.

A mega-block displaced by the Ries impact was cut open by the new road B 25, by passing the village of Fremdingen. The road embankments exhibit a mostly continuous profile from Trossingen Fm (Feuerletten) of the middle Keuper to the Impressamergel Fm. of the lower Weißjura-Group. The thickness profile, corrected for the complex geometry, is discussed in comparison with published regional data. The mega-block with several hundred meters of length and height was pushed radially outward towards the crater rim, followed and accompanied by other blocks. While ploughing through the land surface, it was decelerated by friction, causing internal shear forces. The continuously increasing inclination angle towards the north may reflect a deformation by these forces. Part of the upper strata was sheared off, slided to the northern front of the mega-block and was added there, repeating the sequence from Eisensandstein to Impressamergel Fm. This suggests that the lowest Upper Jurassic made up the surface at the site of origin from where the mega-block was displaced by some 4 km.

In recent years core drillings in the autochthonous vicinity of the Miocene Ries Crater were conducted at different positions. Their lithologic profiles and regional geologic settings are presented. The drillings provide results about strata of the western Franconian Alb and the Riesalb which were not disturbed by the Ries impact.

The field trip leads along the eastern border of the Ries crater from Gosheim to Wemding dealing with rocks of the crater margin. Farther to the north, the small outcrop of Polsingen is visited displaying impact melt rocks (“red suevite”). Along the Rohrach valley the excursion leads to the Ursheim quarry where limestones of the lower Upper Jurassic can be studied. Farther to the north the tectonic structure of the “Schwäbisch-Fränkisches Lineament” is crossed in direction to Hechlingen. In Hechlingen the excursion leads by foot through a hollow way exposing rocks of the Middle Jurassic (“Dogger”). Along the Rohrach valley the excursion reaches Heidenheim with its mediaeval monastery, partially build of rocks of the surroundings. The next stop is at the castle of Spielberg, the northwesterly point of the Franconian alb. The castle rests on ejecta material of the Ries impact. From the castle we have an impressive view on the Keuper-Lias -lowlands in front of the Franconian alb. During the return trip to Nördlingen we visit the famous quarry Aumühle where the two impact formations of the Ries (suevite, Bunte Breccia) can be studied.

An archaeological excavation exposed a prominent mud crack horizon within the laminated lacustrine clays of the Miocene Ries crater fill. Based on lithology and strontium isotope ratios, the 2 m thick partial section can be assigned to the upper part of the laminite unit within the up to 350 m thick lacustrine succession of the central crater. The mud crack horizon confirms previous interpretations of shallow water depths, including temporary subaerial exposure, for the bituminous part of the laminite unit. Furthermore, the surface outcrop of the upper laminite unit at the margin of the central crater basin confirms the bowl-shaped geometry of the sedimentary crater fill. However, sediment deformation and tepee -structure-like fractures within one limestone bed near the section top are post-depositional, and point to solifluction during the Quaternary ice ages.

The results of new geological investigations at the Eireiner quarry near Wemding at the eastern Ries crater margin are presented. The outcropping limestones of the Upper Jurassic can be separated in a parautochthonous and an overthrusted allochthonous zone, separated by a steep thrust surface, which shows a steep dipping to the east. A nearly 100 m deep core drilling in the allochthonous block points to overthrusting upon the parautochthonous block followed by rotation of nearly 180° together with the parautochthonous block.

In the last years several drillings south of the Miocene Ries Crater were conducted which brought stunning results concerning thickness and distribution of the ejecta blanket. With distance from the crater this blanket shows increasing thickness as well as an increasing participation of local material. Some artificial outcrops south of the Danube valley also feature impact controlled displacements like small-to-large-scaled distortions. Concerning the distribution and thickness of the excavated material, an impact direction of the Ries asteroid from the north is favoured. The stratigraphic succession of the ejecta blanket points to erosion of the pre-riesian Molasse strata due to deposition of the excavated material.

In 2017 a 680 m long trench for a water pipeline was excavated in the Nördlinger Ries between Reimlingen and Grosselfingen. This trench exposed a 680 m long, SSW–NNE trending section across a shallow ridge at the inner ring (“crystalline ring”) of the Ries crater. For the first time outcropping basement rocks of the uplifted margin of the central crater were observed at this otherwise submerged part of the inner ring. The slope of the impact-brecciated Variscan basement ridge towards the central crater is covered by algal bioherms and travertines of the Ries crater lake. In turn, the southern slope shows algal bioherms underlain by coarse-grained siliciclastics and associated with carbonate conglomerates. These lake margin sediments interfinger with laminated marls, which point to a lithostratigraphic assignment to the “laminite member” of the central basin succession. Percussion drillings demonstrate the previously unknown, local occurrence of probably early to middle Pleistocene fluvial deposits at the top and slope of the investigated shallow ridge.

The field trip leads from the southern Ries crater to the “Vorries”-zone. Starting in Mönchsdeggingen the tectonic structure of the crater margin as well as sediments of the crater lake are first discussed. Afterwards the excursion leads to the southern “Vorries”-zone, where the autochthonous carbonates of the Upper Jurassic are covered by an ejecta blanket of varying thickness. The ejecta material and the complex hydrogeologic situation around Bissingen and the Kessel valley are presented. During the return trip to Nördlingen a suevite outcrop and the Kartäusertal with the ruins of the former monastery Christgarten are visited.