.
Fig. 1. Location map for the Chiemgau impact region. Published in 2019 Cosmic collision in prehistory The Chiemgau Impact : research in a Bavarian meteorite crater strewn field, M. RappenglückB. RappenglückK. Ernstson

The Chiemgau Meteorite Impact Strewn Field and the Digital Terrain Model: “Earthquake” Liquefaction from Above and from Below

von

DOI http://dx.doi.org/10.13140/RG.2.2.11274.79041

Abstract

The Chiemgau strewn field discovered and established in the early new millennium(Schryvers and Raeymaekers, 2004; Schüssler et al., 2005; Rösler et al. 2005, Rappenglück,M. et al., 2005, Hoffmann et al., 2005, 2006; Yang et al 2008), extensively investigated in thefollowing decade until today (Ernstson et al. 2010, 2011, 2012, 2013, 2014, 2017, 2020, 2023,2024, Hiltl et al. 2011, Isaenko et al. 2012, Rappenglück, B. et al. 2010, 2020 a, b, c, 2021,Rappenglück M.A, et al. 2013, 2014, Bauer et al. 2013, 2019, 2020, Shumilova et al. 2018,Ernstson and Poßekel 2017, 2020 a, b, 2024, Ernstson and Shumilova 2020, Poßekel andErnstson 2019, 2020), and dated to 900-600 BC in the Bronze Age/Iron Age (Rappenglück, B.et al. 2023) comprises far more than 100 mostly rimmed craters scattered in a region of about60 km length and ca. 30 km width in the very South-East of Germany. The crater diametersrange between a few meters and 1,300 m. The doublet impact at the bottom of Lake Chiemseeis considered to have triggered a giant tsunami evident in widespread tsunami deposits aroundthe lake (Liritzis et al. 2010, Ernstson 2016). Geologically, the craters occur in Pleistocenemoraine and fluvio-glacial sediments. The craters and surrounding areas are featuring heavydeformations of the Quaternary cobbles and boulders, impact melt rocks and various glasses,strong shock-metamorphic effects, and multiple geophysical (gravity, geomagnetic,electromagnetic, GPR and seismic) evidence. Impact ejecta deposits in a catastrophic mixturecontain polymictic breccias, strongly shocked rocks, melt rocks and artifacts from BronzeAge/Iron Age people. The impact is substantiated by the abundant occurrence of metallic,glass and carbonaceous spherules, accretionary lapilli, microtektites and of strange, probablymeteoritic matter in the form of iron silicides like gupeiite, xifengite, hapkeite, naquite andlinzhite, various carbides like, e.g., moissanite SiC and khamrabaevite (Ti,V,Fe)C, andcalcium-aluminum-rich inclusions (CAI), minerals krotite and dicalcium dialuminate. Theimpactor is suggested to have been a roughly 1,000 m sized low-density disintegrated, looselybound asteroid or a disintegrated comet to account for the extensive strewn field. A touch-down airburst (Moore et al. 2024 ) is currently being discussed for the Chiemgau impact event(Ernstson 2023).
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https://www.researchgate.net/publication/386905350_The_Chiemgau_Meteorite_Impact_Strewn_Field_and_the_Digital_Terrain_Model_Earthquake_Liquefaction_from_Above_and_from_Below [accessed Jan 15 2025].

Ernstson, Kord & Poßekel, Jens. (2024). The Chiemgau Meteorite Impact Strewn Field and the Digital Terrain Model: “Earthquake” Liquefaction from Above and from Below. 10.13140/RG.2.2.11274.79041.

Fig. 2. Craters of varying size in the impact strewn ellipse. Der crater diameter (for the rim crest) is given in meters. A: Lake Tüttensee (600), B: doublet crater in Lake Chiemsee (800 x 400), C: Purkering (75), D: Bergham (150), E: semi crater in the valley slope of the Inn river, (55), F: Einsiedleiche (15), G: Schatzgrube (13), H: gravel pit, Emmerting (4).
Fig. 5: Geophysical measurements in the crater strewn field. Above: Gravimetric measurements on the frozen Lake Tüttensee crater and its surroundings. The central negative gravity anomaly (-) is mainly generated by the water-filled cavity. The relatively positive anomalies in the frame of the lake (+) are explained by a shock compression of the loose sediments during crater formation. Middle: Ground penetrating radar (GPR) measurements (25 MHz antenna; data: P. Kalenda, R. Tengler, J. Poßekel.) on a profile over the Tüttensee crater ring wall with significant structural features. Radial GPR profiles around the crater with comparable indications "pressure from inside to outside" definitely exclude a dead ice genesis. Below: Geoelectric measurements of the parameter induced polarization over a freshly formed sinkhole ("Thunderhole"). The measurements show the extremely deformed underground caused by the impact "earthquake".
Fig. 4: Extreme pressures, temperatures and corrosion effects in the crater strewn field. A: Typical fracture deformation and corrosion of an Alpine cobble - exposed during a gravel pit expansion. B: Broken boulder fragment of a sandstone; from crater 004 (near Emmerting). C: Extremely corroded limestone block from the edge of Lake Chiemsee. Effect of carbonate melt and/or acid dissolution. D: Intensively baked rocks - fractured cobble and quartzite fragment with glass coating (from crater 004). E: Two extremely short-lived and highly heated pebbles with sub-millimeter thin glass skin all around; relic fragment from decarbonization/carbonate melt of an Alpine limestone cobble (from crater 004). F: Chiemite from the Chiemgau crater strewn field under the scanning electron microscope. The content of special carbon allotropes (carbyne) requires temperatures between 2500 and 4000°C to form. G: Aerodynamically shaped black glasses that can be abundantly picked up in the crater strewn field. H: Example of a microtektite from soil samples in the first Alpine foothills south of Lake Chiemsee. J, K: Strong shock effects in minerals - optically isotropic, normally birefringent minerals mica (g) and feldspar (f) are converted to diaplectic glass. q = ordinary quartz. J = crossed polarizers, K = linearly polarized light. Thin section of a quartzite from the
Fig. 6: Iron silicides from the Chiemgau crater strewn field. A: 8 kg heavy iron silicide boulder; found about 30 years ago near Grabenstätt at Lake Chiemsee. B: Iron silicide samples from the strewn field with aerodynamically shaped forms and surfaces. C: Iron silicide particles from the strewn field with regmaglyptic surface sculpture. D: Fine-grained fraction of iron silicides from the strewn field. E, F: Iron silicides under the scanning electron microscope (SEM). G: Cubic moissanite (SiC) crystals in iron silicide matrix. H: Iron silicide with uranium and cerium (light), SEM. I: Crystals of moissanite (black) and titanium carbide (TiC, grey) in iron silicide matrix. J: Microcrater on iron silicide (impact of cosmic dust particles?), REM. K: Exsolution lamellae of iron silicide and zircon in iron silicide sample, SEM. L: Zircon crystals immersed in plastic iron silicide matrix.
Fig. 3. The Formation of the Lake Tüttensee depression as a meteorite crater (schematic, not to scale). As far as the LfU drill hole is concerned: It is located outside the actual crater.
Fig. 7: Projectile and crater grading. Breaking of the asteroid/comet nucleus during the approach, grading of the fragments according to size. Accordingly there is a very rough arrangement of the craters in the scattering ellipse depending on their size. Strongly schematized.
Fig. 1. Location map for the Chiemgau impact region. Published in 2019 Cosmic collision in prehistory The Chiemgau Impact : research in a Bavarian meteorite crater strewn field, M. RappenglückB. RappenglückK. Ernstson