ASGP (2018), vol. 88: 303–319

SOLUTION-COLLAPSE BRECCIAS IN THE UPPER OLENEKIAN–LADINIAN SUCCESSION, TATRA MTS, POLAND

Piotr JAGLARZ & Tomasz RYCHLIŃSKI

Jagiellonian University, Faculty of Geography and Geology, Institute of Geological Sciences, Gronostajowa 3a; 30-387 Kraków, Poland; e-mails: piotr.jaglarz@uj.edu.pl, tomasz.rychlinski@uj.edu.pl

Jaglarz, P. & Rychliński, T., 2018. Solution-collapse breccias in the upper Olenekian–Ladinian succession, Tatra Mts, Poland. Annales Societatis Geologorum Poloniae, 88: 303–319.

Abstract: The upper Olenekian–Middle Triassic succession of the Tatricum domain (Central Western Carpathians, southern Poland) includes a few horizons of breccias, which are intercalated with early-diagenetic dolostones. On the basis of macroscopic and microscopic (including cathodoluminescence) observations, the paper presents a new interpretation of the genesis of the breccias and their diagenetic history. The rocks studied range from monomictic, cemented mosaic packbreccias to chaotic, unsorted, monomictic, particulate rubble floatbreccias. The processes that preceded the formation of the breccias encompassed the precipitation of evaporites and the early-diagenetic dolomitization of lime muds. The solution-collapse breccias were formed during episodes of cyclic sediment emersions in the upper Olenekian and Middle Triassic, as the result of gradual sediment collapse after karstic dissolution of the intercalated evaporites. After the brecciation process, during diagenesis the rocks were subjected to cementation by sulphate minerals and next, to multi-stage dolomitization. Later tectonic processes led to fracturing and even re-brecciation of the previously formed solution-collapse breccias.

Manuscript received 23 February 2018, accepted 20 December 2018