Impact craters and the extraterrestrial matter in their surroundings: case of Morasko (Poland) and Kaali (Estonia)

Abstract

Investigations have been carried out in the area of meteorite impact craters within the Quaternary deposits in Morasko and the Silurian bedrock in Kaali. Both surface destructions occurred during the fall of cosmic bodies that induced formation of magnetic fine-grained material. The presence of extraterrestrial spherules in Morasko and Kaali and their cosmic origin state prove such a composition and character of the surface. Moreover, the amount of magnetic fraction is increased in the sediments in the environs of craters in relation to their surroundings. However, impact of similar meteorites under similar environmental conditions can generate various morphological, mineralogical and natural effects. Common features of the described areas are the occurrence of collateral craters, their formation in sedimentary rocks and presence of high amounts of extraterrestrial spherules in their environs.

The Kaali Impact as Trigger of a Mega-Tsunami Event and Violent Seismotectonics in Sweden

“…Supplementary Material to this paper has been posted on ResearchGate [1]. It consists of 3 papers; Observational facts on seismotectonics and a mega-tsunami in Sweden (Mörner; p. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], Radiocarbon chronology of the Kaali Impact (Duffy; p. [19][20][21] and Searching for a larger meteor fragment falling into the Bal-tic Sea (Mörner & Duffy;.…”

Late Holocene Vistula River Floods Recorded in Grain Size Distributions and Diatom Assemblages of Marine Sediments of the Gulf of Gdańsk (Baltic Sea)

“…1), has an area of ca. 4940 km 2 , with an average depth of 59 m (Majewski, 1994) and a maximum depth of 110 m in the Gdańsk Deep (Uścinowicz et al, 1998). The Gulf of Gdańsk was predominantly shaped by the Pleistocene glaciations and the following erosional and accumulation processes, related mainly to sea-level changes (Uścinowicz, 2003(Uścinowicz, , 2006Uścinowicz et al, 2007;Witak, 2010Witak, , 2013aWitak, , 2013b and sediment supply from the Vistula River.…”

“…The latter is the longest river flowing into the Baltic Sea, with catchment including most of the territory of Poland (over 194,420 km 2 ). The modern sediments in the Gulf of Gdańsk mainly come from the Vistula River, coastal erosion, and human activity (Uścinowicz et al, 1998). Their grain size type is generally related to water depth (Fig.…”

Identification of a circular structure in eastern Pomerania (northern Poland) – a hypothesis of its origin

“…The is sue of ac quir ing and re tain ing the crat ers in young un con sol i dated sed i ments was raised sev eral times (Stankowski, 2001;Stankowski et al, 2007;Uoecinowicz, 2014). How ever, none of the cases re ferred to ex am ples that are tens of kilo metres in di am e ter.…”

“…They have been as cribed to endogenic pro cesses such as vol cano-tec tonics, in tru sions, and salt tec ton ics, but also to exo gen ic processes such as karstification or the im pact of me te or ites (Goulty et al, 2001;Bertoni and Cart wright, 2005;Matton et al, 2005;French and Koeberl, 2010;Alsouki et al, 2011). Sev eral im pact struc tures that are known from Eu rope were formed un der differ ent con di tions, and their age var ies greatly, just like their state of pres er va tion and their sizes from rel a tively small to consid er able (Pohl et al, 1977;Stankowski, 2001;Stoffler et al, 2001;Surroja and Surroja, 2010;Juhlin et al, 2012;Uoecinowicz, 2014).…”