Microtektites from the Chiemgau impact fallout

Tektites are well-known gravel-size natural glasses that according to current knowledge form in the very early process of impact cratering by melting and/or vaporizing of superficial soil and rocks ejected as melt or vapor from the impact crater. On reentry in the atmosphere and cooling, the glass bodies exhibiting characteristic shapes fall to Earth where they form part of the impact ejecta. By definition tektites that are smaller than 1 mm are called microtektites. Although the origin of tektites from impact events is generally accepted the exact mode of formation is not well understood.

In the Chiemgau meteorite crater strewn field impact glasses are found widespread in various formations, and tektite-like bodies of a dense black glass with vesicles have attracted considerable attention (Fig. 1).

tektite-like glass, Chiemgau-impact, similar to irghizites

Fig. 1. Dense black glass particles from the Chiemgau impact strewn field frequently exhibiting tektite-like shape and twisted form similar to irghizites from the Zhamanshin impact crater. These are NOT the Chiemgau microtektites! – Click to enlarge.

Outside the crater strewn field in the foothills of the Alps at some 1500 m altitude (Fig. 2) a systematic search for impact fallout has revealed not only abundant tiny iron silicide particles (e.g., minerals xifengite and gupeiite) but also microtektites widely distributed in the soils (Fig. 3).

Fig. 2. Location map for the Chiemgau impact meteorite crater strewn field and the sites of the microtektite finds. Google maps. – Click to enlarge.

They show the very typical splash shapes like spheres, teardrops and irregular dumbbells (Fig. 3). They are fully transparent and have a mostly yellowish-brownish-grayish color. Bubble inclusions are frequent.

microtektites from the Chiemgau impact strewn field Fig. 3. Typically shaped microtektites from the soil in the foothills of the Alps near the Chiemgau impact crater strewn field. Optical microscope images, 100 µm scale bar in each case.

The SEM micrographs in Fig. 4 especially point to the in part very strange surface features and bizarre forms exhibiting micrometer-sized glass filaments and twisted bodies.

Chiengau impact microtektites SEM

Fig. 4. SEM images of microtektite-like glass particles.
Note the tiny, micrometer-sized glass filaments (lower
right) of the particle over it.


Microtektites are known, e.g., from the North American strewn field (cores from the Deep Sea Drilling Project), from the Australasian tektite strewn field, from the Ivory Coast strewn field and seem to be associated with the Chicxulub KT impact and Late Eocene impacts. A problem with proposed microtektite occurrences may arise from a possible confusion with spherules of an origin other than from impact vapor/melt solidification especially when a direct relation with an impact site is lacking. Even volcanic spherules may show dumbbell and teardrop shapes, while industrially produced microscopic glass spheres (e.g. from fly ash) have in general no teardrop or dumbbell counterparts.  A comprehensive consideration of the various possibilities including volcanic, man-made and even organic matter is given by Glass & Simonson (2013).

In the case of the Chiemgau impact microtektites a confusion with volcanic or man-made glass particles can be excluded with a high degree of probability since the very nearby really existing impact site and the exceptionally typical shape of known microtektites provide the simplest explanation for their origin. Nevertheless, a thorough analysis of their composition and a highly magnifying SEM imagery of their surfaces are in progress. Perhaps, some more insight into the general process of microtektite formation – in this case possibly as an impact vapor plume condensate – can be attained.


Glass, B. P. and Simonson, B.M. (2013): Distal Impact Ejecta Layers: A Record of Large Impacts in Sedimentary Deposits. – Impact Studies, 400 p., Springer.

The Chiemgau meteorite crater strewn field: the impact once again has piped up (in the field and in the media)

A new Thunderhole (Donnerloch) and reactions

Since our contribution (Dec 2, 2011) on the impact-induced rock liquefaction (soil liquefaction) and the Thunderhole phenomenon, quite a few new sinkholes have occurred in the Kienberg region north of Lake Chiemsee. The latest somewhat spectacular cave-in happened two weeks ago. A family of mushroom pickers underway in the forest suddenly stopped at a freshly collapsed hole, 1-2 m in diameter and, as later measured, 8 m deep (Fig. 1). Having had a severe scare they at once informed police and fire department for securing the dangerous place. And this was the way the Thunderhole phenomenon for the first time found its way to the media, and newspapers, sound radio and television reported on this “fantastic story” widely initiating public awareness of this geologic hazard in the region. And now people got informed about large ponds and septic tanks having run dry overnight, about broken front axles when farmers had run with their tractor into a suddenly collapsed Thunderhole, about trees that suddenly began to incline, about beginning soil  subsidence several meters wide immediately besides a road, about a Thunderhole exactly on a crossroad, about big open cavities in the underground that had to be sealed by enormous quantities of cement before a new fire station could be built, and so on.

Donnerloch Chiemgau impact

Fig 1. The new 8 m deep Thunderhole in the Kienberg region. Photo H. Schiebl.

To investigate the newly formed Thunderhole geologically we performed a geophysical survey of complex resistivity measurements (resistivity and induced polarization electrical imaging, Fig. 2), and we found the same geologic scenario we had established earlier when we had applied voluminous excavations and geoelectrics to other Thunderholes: The origin of the Thunderholes is closely related with soil liquefaction accompanied by strongest movements of  sand, gravel and big rock boulders bottom up, and the sinkhole character is a later, secondary effect only. And like with strongest earthquakes the Chiemgau Thunderhole rock liquefaction was initiated by the shock of the gigantic Chiemgau meteorite impact event in the Bronze Age/Celtic era.

geoelectric pseudosections across thunderhole Chiemgau impact

Fig 2. The Thunderhole sinkhole and a larger endangered area seen in apparent resistivity and induced polarization pseudosections.

Amazingly (not to say ridiculously enough), the officials of the geological survey of Bavaria (Landesamt für Umwelt, LfU) and the local geologist Dr. Robert Darga from the Siegsdorf museum are completely trivializing the phenomenon declaring the Thunderholes as dead-ice holes and speaking of quite normal sinkholes as having occurred in thousands all over Bavaria. Hence they are absolutely ignoring the detailed geological and geophysical investigations of the phenomenon, while contradicting all serious science and research. To understand this highly nonscientific behavior one must know that the officials of the geological survey and Dr. Darga are fearing the Chiemgau impact event come hell or high water …

Chiemgau impact: a new article on carbon allotropes from the meteorite crater strewn field

From biomass to glassy carbon and carbynes: evidence of possible meteorite impact shock coalification and carbonization

K. Ernstson, T. G. Shumilova, S. I. Isaenko, A. Neumair, M. A. Rappenglück


Shortly after the meeting, May 19-22, in Syktyvkar the 546 pages Proceedings volume has been published:

Modern problems of theoretical, experimental and applied mineralogy (Yushkin Memorial Seminar–2013): Proceedings of mineralogical seminar with international participation. Syktyvkar: IG Komi SC UB RAS, 2013. 546 p.

The above-mentioned contribution by Ernstson et al. addresses the many various carbon modifications (among them the chiemite probable impactite featuring highest pressures and temperatures) pointing to a shock coalification of the vegetation affected by the Chiemgau impact in southeast Germany. Shock coalification in this case is to be understood, different from the long-lasting geologic coal formation (organic matter > peat > lignite > hard coal > anthracite), as an immediate short-term conversion of organic matter (in particular wood, peat) to highest coalification levels spontaneously leading to glass-like carbon and chiemite by the extreme impact shock. The model is strongly supported by many finds such as diatoms and cyanobacteria in very dense, hard glass-like carbon and wood particles that are baked into the high-pressure/high-temperature chiemite.

The abstract article from the Proceedings volume can be clicked HERE. The respective POSTER may also be clicked and downloaded.


Chiemgau impact: taking a look at Russia

The Tschebarkul 2013 super bolide, Tscheljabinsk, Russia – what do we currently know? 

Explosion and impact of the meteor: In the meantime the commotion has died down and has given way to more factual information and scientific relevance, and here on our website we would like to dedicate sufficient coverage of the current knowledge.

Such an event that we have now witnessed in Russia undoubtedly highlights also the Chiemgau impact and the related discussions about the impact parameters like the kind of impactor, fragmentation in the atmosphere and the dimensions of the strewn field.

 Source: Svetlana Korzhava; WIKIMEDIA COMMONS

Important information is coming directly from Russia where as is well known good scientific relations of the CIRT exist, and we thank particularly Dr. Slava Gusiakov from the Holocene Impact Working Group for his personal communication.

Our article:  Continue reading

Chiemgau impact – new article: On the geology of the Chieming-Stöttham archeological excavation


K. Ernstson, C. Sideris, I. Liritzis, A. Neumair


ABSTRACT. – Archaeological excavation at Chieming-Stöttham in the Chiemgau region of Southeast Germany revealed a diamictic (breccia) layer sandwiched between a Neolithic and a Roman occupation layer. This exotic layer bears evidence of its deposition in a catastrophic event that is attributed to the Chiemgau meteorite impact. In the extended crater strewn field produced by the impact, geological excavations have uncovered comparable horizons with an anomalous geological inventory intermixed with archaeological material. Evidences of extreme destruction, temperatures and pressures including impact shock effects suggest that the current views on its being an undisturbed colluvial depositional sequence as postulated by archaeologists and pedologists/geomorphologists is untenable.

The article addresses the geologic inventory of the archeological excavation at Chieming-Stöttham in the year 2007, the impact  features of the intercalated catastrophic layer and the relation to the Chiemgau impact. The article also emphasizes the basically different viewpoints of the geomorphological-pedologic work (escorting the archeological excavation and performed at the behest of Bayerisches Landesamtes für Denkmalpflege by Prof. J. Völkel, Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt der technischen Universität München) on the one hand, and the geologic-mineralogic-petrographical work of the impact researchers on the other hand.

Chiemgau impact: the dual crater at the bottom of Lake Chiemsee – nice counterparts

Since a few years there is evidence of a dual meteorite crater at the bottom of Lake Chiemsee (Fig. 4) in the Chiemgau meteorite crater strewn field. The search for a suspected impact into the lake was originally based on reports of fishermen about unusual sharp-edged large stones at the lake bottom that had damaged their fishnets. Such stones are in fact foreign matter in the lake. A general echo sounder campaign, followed by a detailed survey veritably revealed a peculiar structure, likewise a foreign element in the lake, with all evidence of a rimmed doublet crater (Fig.1).

doublet meteorite crater at the bottom of Lake Chiemsee, Chiemgau impact strewn fieldFig. 1. The proposed meteorite doublet crater at the bottom of Lake Chiemsee from detailed sonar echo sounder measurements. Meter scale indicates water depth.

The similarity to meteoritic dual craters on Mars is striking (Fig. 2). From the Mars image it is evident that the doublet structure formed on synchronous impact of twin projectiles. Continue reading

Chiemgau impact: is there a parallel with the Saarland region?

map of Germany showing the Saarland impact and Chiemgau impact locations

Do they form a pair? The Chiemgau impact and the suspected Saarland impact.

The earlier stated assumption that the Chiemgau impact may have a counterpart in the Saarland region


has been strengthened by new finds and new geologic and petrographic features. A respective update article may be clicked here:


Chiemgau impact: presentation at the first European Mineralogical Conference 2-6 September 2012 – Frankfurt, Germany

Session Meteorites and Planets

Carbynes and DLC in naturally occurring carbon matter from the Alpine Foreland, South-East Germany: Evidence of a probable new impactite

S. Isaenko, T. Shumilova, K. Ernstson, S. Shevchuk, A. Neumair, and M. Rappenglück

ABSTRACT download EMC2012-217.


diamond like carbon (DLC) in the impactite from the Chiemgau impact strewn field

From the poster: diamond-like carbon (DLC) in the probable impactite from the Chiemgau meteorite impact crater strewn field.

Chiemgau impact: presentation at the 34th International Geological Congress, 5-10 August 2012 – Brisbane, Australia

Every four years the International Union of Geosciences (IUGS) coordinates the International Geological Congress.

After a contribution at the 33th congress 2008 in Oslo the CIRT had now a presentation at the this year’s meeting in Brisbane, Australia:

A prehistoric meteorite impact in Southeast Bavaria (Germany): tracing its cultural implications


Abstract. – A meteorite crater field in Southeast Germany, the Chiemgau region, comprises more than 80 craters scattered in an area of about 60 km x 30 km. The crater diameters range between a few meters and 600 m, forming one of the biggest known areas of Holocene meteorite craters. Continue reading