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Geo log i cal Quar terly, 2020, 64 (2): 321–341 DOI: http://dx.doi.org/10.7306/gq.1539 Detri tal zir con age data from the con glom er ates in the Upper Silesian and Małopolska blocks, and their im pli ca tions for the pre-Variscan tec tonic evo lu tion (S Po land) Ryszard HABRYN1, *, Ewa KRZEMIŃSKA2, Leszek KRZEMIŃSKI2, Marek MARKOWIAK1 and Grzegorz ZIELIŃSKI2 1 Pol ish Geo log i cal In sti tute – Na tional Re search In sti tute, Up per Silesian Branch, Królowej Jadwigi 1, 41-200 Sosnowiec, Po land 2 Pol ish Geo log i cal In sti tute – Na tional Re search In sti tute, Rakowiecka 4, 00-975 Warszawa, Po land Habryn, R., Krzemińska, E., Krzemiński, L., Markowiak, M., Zieliński, G., 2020. Detri tal zir con age data from the con glom er- ates in the Up per Silesian and Małopolska blocks, and their im pli ca tions for the pre-Variscan tec tonic evo lu tion (S Po land). Geo log i cal Quar terly, 64 (2): 321–341, doi: 10.7306/gq.1539 As so ci ate Ed i tor: Leszek Marks De tri tal zir con age of the con glom erates from the Up per Silesian (USB) and Małopolska (MB) (S Poland) have been in ves ti - gated to com pare their depo si tion age and pos si ble pro veni ence. The size and poor sort ing of the lithoclasts reflect a short trans por ta tion, with de po si tion close to the sourceland. The Late Ediacaran con glom er ate of the Potrójna IG 1 and Raciechowice 1 boreholes (USB) re veal a good match be tween the ages known from the lo cal base ment explored by bore - holes. De tri tal zir con clus ters in a range of 579–585 Ma and 628–638 Ma and of 707 Ma are con sis tent with the dis tri bu tions of Cadomian magmatism within the nearest orogenic belt or those iden ti fied else where within the Brunovistulicum. In case of the con glom er ate de pos ited in the Batowice 2 borehole (MB), the zir con clus ters of 532, 551, 594 and 649 Ma, ac com pa nied with a pre-Svecofennian group peaked at 2071 Ma, and the lack of Sveconorvegian pop u la tion may doc u ment a tectono-sed i men tary in ter ac tion be tween the Baltica’s south ern margin and the Gondwanan Cadomian and Late Cadomian base ment during Early Paleo zoic time. This con glom erate bed was depos ited later, af ter the Early Ordo vi cian, then dock ing of Małopolska Block – Baltica was proba bly completed. Key words: Teisseyre-Tornquist Terrane As sem blage, max i mum de po si tion age, prox i mal source, prov e nance, Cadomian orogen, Baltica. INTRODUCTION (Kodama, 1994; Fer gu son et al., 1996) and there fore may have a par tic u lar ap pli ca tion for the prov e nance study of prox i mal sources. The U-Pb de tri tal zir con geo chron ol ogy of sed i ments pro - In gen eral, the con glom er ates, as spe cific im ma ture sed i - vides in for ma tion about the age of clastic com po nents and, in ments, are de pos ited rel a tively close to the sourceland and typi - some cases, con strains a de po si tion time of sed i men tary units. cally asso ci ated with re gions of high tec tonic ac tiv ity. The large Iden ti fy ing spe cific age pop u la tions en ables more re gional size of the clasts and their poor sort ing re flect short dis tances of and palaeogeographic com par i sons be tween other units and trans por ta tion. match ing them with poten tial sed i ment-source ar eas. Many of This as pect of de tri tal zir con geo chron ol ogy has been ex - the prov e nance age de ter mi na tions have been made on zir con plored by sampling con glom er ate de pos its from the Up per grains ex tracted from sand-sized clastic rocks that are trans - Silesia Block and the Małopolska Block. Both blocks are situ - ported usu ally over thou sands of kilo metres (Pell et al., 1997; ated in the area be tween the west ern edge of an cient litho - Sircombe, 1999; Bassett, 2000). However, coarse-grained de - sphere of the East Eu ro pean Craton (EEC) and the younger pos its, in clud ing con glom er ates, arise as a re sult of much litho sphere of the Pa leo zoic ter ranes of Cen tral and West ern shorter trans port dis tances, e.g. tens to hun dreds of kilo metres Eu rope (Fig. 1A). At the end of the Neoproterozoic they formed the south ern most part of the Teisseyre-Tornquist Terrane As - sem blage (Nawrocki and Poprawa, 2006; Żelaźniewicz et al., 2009), fi nally amalgam ated in Early Paleo zoic time (Buła, 2000; Belka et al., 2002), or as the prox i mal ter ranes de tached from * Corresponding author, e-mail: [email protected] the cratonic mar gin and re-accreted af ter dextral trans la tion Received: August 7, 2019; accepted: March 11, 2020; first (Dadlez et al., 2005). published online: June 15, 2020 322 Ryszard Habryn, Ewa Krzemińska, Leszek Krzemiński, Marek Markowiak and Grzegorz Zieliński Fig. 1A – the po si tion of the USB as a part of the Brunovistulian Terrane and the MB at the sub-Perm ian-Me so zoic palaeosurface on a tec tonic sketch map of Cen tral Eu rope (af ter Mazur and Jarosiński, 2006; Nawrocki and Poprawa, 2006); CDF – Cal edonian Defor - ma tion Front, FSS – Fennoscandia-Sarmatia Su ture, GFZ – Grójec Fault Zone, HCF – Holy Cross Fault, KLFZ – Kraków-Lubliniec Fault Zone, VDF – Variscan De for ma tion Front (af ter Pożaryski et al., 1992), WLH – Wolsztyn-Leszno High; the lo ca tions of drill holes are marked by black circles P – Potrójna IG 1, R – Raciechowice 1 (USB), B – Batowice 2 (MB); B – geo logi cal sketch map with out for ma tions youn ger than Pre cam brian in the area of the Up per Silesian Block and SE part of the Małopolska Block (after Buła and Żaba, 2005; Buła et al., 2015 mod i fied), show ing the lo ca tion of the Potrójna IG 1, Raciechowice 1 and Batowice 2 bore - holes and ad ja cent bore holes reach ing Pre cam brian rocks Their ac cre tion pro cess and par tic u lar paths of evo lu tion The state of knowl edge for both ar eas is not equiv a lent. Even that re fer to Late Ediacaran and Early Paleo zoic times are still a in com plete data in di cate a dis tinct palaeo geo graphi cal, fa cies mat ter of de bate (Dadlez et al., 1995, 2005; Pha raoh, 1999; and palaeotectonic de vel op ment (Buła, 2000; Buła et al., 2008) Belka et al., 2000, 2002; Nawrocki and Poprawa, 2006; of USB and MB dur ing the Pre cam brian and Early Pa leo zoic. Narkiewicz et al., 2015; Walczak and Belka, 2017). An other The USB is com monly referred to as the ex otic ter ranes with widely discussed is sue re mains an af fin ity of these crustal units. re spect to the EEC (or Baltica). There is no close palaeo - De tri tal zir con age data from the con glom erates in the Up per Silesian and Małopolska blocks, and their im pli ca tions... 323 geographic re la tion of both the do mains dur ing the Early Cam- mian Mas sif from the east (Dudek, 1980; Buła and Żaba, 2005, brian (Nawrocki et al., 2001). Usu ally, USB is in ter preted as Kalvoda et al., 2007). Be sides USB, the BVT in cludes also the hav ing been de rived from the Cadomian mar gin of Gond wana Brno Mas sif (Block), and the Thaya and Slavkov units lo cated or Avalonia and fi nally docked to Baltica be fore the Early Devo - on the ter ri tory of the Czech Re pub lic, where several types of nian (Belka et al., 2000, 2002; Nawrocki and Poprawa, 2006). granitoids and gneiss es have been doc u mented (Friedl et al., In con trast, the MB is in ter preted to be an in te gral part of 2004; Buła and Żaba, 2005, 2008; Kalvoda et al., 2008). The Baltica mar gin, lo cated in the pres ent-day posi tion dur ing the bound ary betw een the USB and the Brno Block is de ter mined whole Pa leo zoic (e.g., Dadlez, 2001; Jaworowski and Sikorska, by the Hána Fault de vel oped on pre-Cam brian foun da tions 2006) or sup posed to have been docked to Baltica in the Late (Buła et al., 2008, 2015). The west ern bound ary of the BVT, at Cam brian (Belka et al., 2000, 2002; Valverde-Vaquero et al., the con tact with the Moldanubicum of the Bo he mian Mas sif, is 2000; Winchester et al., 2002; Nawrocki and Poprawa, 2006; marked as the Moravo-Silesian Fault Zone (Buła et al., 2015).