Three Late Silurian carbonate proWles of the Malynivtsy and Skala Formations from Podolia (western Ukraine) are discussed in terms of sedimentation dynamics. Their common feature is the appearance of thick, stromatoporoid-rich beds within Wne-grained peritidal deposits. These intercalations are composed of fossils typical of oVshore sedimentary environments. In the most spectacular case, a channel, several tens of metres wide and inWlled with stromatoporoids, is incised in a peritidal cyclic complex. The successions investigated exhibit sedimentary features that are diagnostic of onshore redeposition. Independently of the scale of the recorded sedimentary events, the onshore redeposition was caused by factors with energy levels exceeding those of average storms, probably by hurricanes or even tsunami waves. The dynamic nature of some of the stromatoporoid beds has to be taken into account when constructing the curves illustrating bathymetrical and facies development of the Silurian succession of Podolia. The genesis of lens-shaped stromatoporoid beds, elongated depending on their origin, either parallel or perpendicular to the facies belts, should be considered an important factor in reconstructions of the depositional architecture of sedimentary hydrocarbon collectors.

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LETHAIAŁuczyń ski, P. 2006 12 01: Stromatoporoid shape and burial ratio changes during growth history and their methodological consequences in morphometrical analyses. Lethaia , Vol. 39, pp. 339 Á358. Oslo. ISSN 0024-1164. Eight Devonian stromatoporoids with clearly exposed arrangements of latilaminae were subjected to detailed morphometrical analyses. Distinctive sets of latilaminae were marked on photographs taken from polished specimens, which allowed reconstruction of their individual growth histories by presenting consecutive stages of their growth. The growth forms measured above the sediment surface and the overall shapes of the skeleton at a given time have proved to differ distinctly between each other throughout the growth history of these stromatoporoids. The morphometrical features of individual specimens (both of their growth forms and of their whole skeletons) distinctly changed throughout their development. Changing environmental factors directly influenced the growth form above the sea floor, and each specimen shows its own specific history of growth form changes. Instead, overall shapes of the skeleton of most of the studied specimens changed in a similar general manner resulting from growth during sediment accumulation. Basing the palaeoenvironmental considerations only on the stromatoporoids' final shapes may thus be very misleading. It is therefore suggested that the ascription of a specimen to a particular morphometrical category should be based on the mode of its growth history represented by a curve recording the V /B changes (vertical height versus basal length) during consecutive growth stages. Certain sedimentary processes have their direct reflection in the mode of stromatoporoid growth, and are recorded by the attributes of the shape profile (V /B ), and burial ratio (BR ) curves, which allows deciphering such features as, for example, periodicity of sediment supply, substrate consistency and tempo of sediment cementation. This is particularly valuable when the deposits are recrystallized and the sedimentary structures are not visible. The paper also tests the applicability of the new definitions of the parameters describing the stromatoporoid shape introduced recently by the author. I Burial ratio, measurements, ontogenesis, shape changes, stromatoporoids.

ABSTRACT:Łuczyński, P., Skompski, S. and Kozłowski, W. 2014. Stromatoporoid beds and flat-pebble conglomerates interpreted as tsunami deposits in the Upper Silurian of Podolia, Ukraine. Acta Geologica Polonica, 64 (3), 261-280. Warszawa.Tsunami deposits are currently a subject of intensive studies. Tsunamis must have occurred in the geological past in the same frequency as nowadays, yet their identified depositional record is surprisingly scarce. Here we describe a hitherto unrecognized example of probable palaeotsunamites.The Upper Silurian (Pridoli) carbonate succession of Podolia (southwestern Ukraine) contains variously developed event beds forming intercalations within peritidal deposits (shallow water limestones, nodular marls and dolomites). The event beds are represented by stromatoporoid and fine-grained bioclastic limestones, in some places accompanied by flat-pebble conglomerates. The interval with event beds can be traced along the Zbruch River in separate outcrops over a distance of more than 20 km along a transect oblique to the palaeoshoreline. The stromatoporoid beds have erosional bottom surfaces and are composed of overturned and often fragmented massive skeletons. The material has been transported landward from their offshore habitats and deposited in lagoonal settings. The flat-pebble conglomerates are composed of sub-angular micritic clasts that are lithologically identical to the sediments forming the underlying beds.Large-scale landward transport of the biogenic material has to be attributed to phenomena with very high energy levels, such as tropical hurricanes or tsunamis. This paper presents a tsunamigenic interpretation. Morphometric features of redeposited stromatoporoids point to a calm original growth environment at depths well below storm wave base. Tsunami waves are the most probable factor that could cause their redeposition from such a setting. The vastness of the area covered by parabiostromal stromatoporoid beds resembles the distribution of modern tsunami deposits in offshore settings. The stromatoporoid beds with unsorted stromatoporoids of various dimensions evenly distributed throughout the thickness of the beds and with clast-supported textures most probably represent deposition by traction. In some sections, the stromatoporoids are restricted to the lowermost parts of the beds, which pass upwards into bioclastic limestones. In this case, the finer material was deposited from suspension. The coexistence of stromatoporoid beds and flat-pebble conglomerates also allows presenting a tsunami interpretation of the latter. The propagating tsunami waves, led to erosion of partly lithified thin-layered mudstones, their fragmentation into flat clasts and redeposition as flat-pebble conglomerates.

Improving the parameterization of stromatoporoid shapes -a detailed approach to stromatoporoid morphometry PIOTR ŁUCZYŃ SKI Łuczyń ski, P. 2005 06 15: Improving the parameterization of stromatoporoid shapes -a detailed approach to stromatoporoid morphometry.

ABSTRACT:Łuczyński, P., Kozłowski, W. and Skompski, S. 2015. Regressive-transgressive cyclothem with facies record of the re-flooding window in the Late Silurian carbonate succession (Podolia, Ukraine). Acta Geologica Polonica, 65 (3), 297-318. Warszawa.The term "re-flooding window" was recently proposed as a time-interval connected with the transgressive stage of present day peri-reefal development. In the analysis presented here, a fossil record of a re-flooding window has been recognized. Nine Late Silurian carbonate sections exposed on the banks of the Dnister River in Podolia (Ukraine) have been correlated base on bed-by-bed microfacies analysis and spectral gamma ray (SGR) measurements. Correlated were sections representing settings ranging from the inner part of a shallow-water carbonate platform to its slope, through an organic buildup. The reconstructed depositional scenario has been divided into six development stages, with the first three representing a regressive interval and the latter three a transgressive interval of the basin's history. The re-flooding window has been identified at the beginning of a transgressive part of the succession. Surprisingly, it is characterized by an extremely fast growth of a shallow, tide-dominated platform and by deposition of calciturbiditic layers in a more basinal area. The interpreted succession is a small-scale model illustrating the reaction of carbonate depositional sub-environments to sea level changes and determining the facies position of the stromatoporoid buildups within the facies pattern on a Silurian shelf. The use of SGR analyses in shallow water, partly high-energy, carbonate facies, both for correlation purposes and for identifying depositional systems, is a relatively new method, and thus can serve as a reference for other studies of similar facies assortment.

1 Uni ver sity of War saw, In sti tute of Ge ol ogy, Żwirki i Wigury 93, 02-089 Warszawa, Po land Jezierska, A., Łuczyński, P., 2016. Ju ras sic un con formi ties in the High-Tatric suc ces sion, Tatra Moun tains, Po land. Geo log ical Quar terly, 60 (2): 273-290, doi: 10.7306/gq.1255 Dur ing the Tri as sic/Ju ras sic bound ary in ter val and in the Ju ras sic, the Tri as sic car bon ate plat forms oc cu py ing the north ern shelf of the West ern Tethys were sub jected to dis in te gra tion. Re cord of these pro cesses in the Al pine-Carpathian area is incom plete and con tains a num ber of strati graphic gaps. In the High-Tatric suc ces sion of the Tatra Moun tains (Cen tral Western Carpathians) strati graphic gaps ex pressed by un con formity sur faces oc cur be tween the Tri as sic and the Mid dle Ju ras sic. In par tic u lar ar eas, the Tri as sic is di rectly over lain by the Dudziniec For ma tion (Sinemurian-Bajocian), the Smolegowa For ma tion (Bajocian), the Krupianka For ma tion (Bathonian) or the Raptawicka Turnia For ma tion (Callovian-Hauterivian). The oc cur rence of Bajocian and Bathonian de pos its is lim ited to iso lated len tic u lar bod ies or to in fill ings of nep tu nian dykes pen e trat ing the Tri as sic. Spa tial re la tions be tween par tic u lar Ju ras sic lithosomes and the oc cur rence of strati graphic gaps be tween par tic u lar units al low dis cern ing four main un con formi ties. In the strati graphi cal or der these are: base of the Dudziniec For ma tion (ero sional un con formity), base of the Smolegowa For ma tion (penacordance or paraconformity), base of the Krupianka For ma tion (ero sional un con formity) and base of the Raptawicka Turnia For ma tion (drown ing un con formity). Fol low ing ep i sodes of ero sion mod i fied the pre vi ously de vel oped un con formity sur faces, which resulted in com plex mod ern ar chi tec ture of the Tri as sic/Ju ras sic con tact, as well as be tween par tic u lar Ju ras sic for ma tions.

ABSTRACT:Łuczyński, P., Skompski, S. and Kozłowski, W. 2016. Recent studies on the Silurian of the western part of Ukraine. Acta Geologica Polonica, 66 (3), 281-297. Warszawa.The paper summarises the effects of recent studies carried out by a team from the Department of Historical and Regional Geology of the Faculty of Geology, University of Warsaw on the upper Silurian of Podolia (western part of Ukraine).The sedimentary history of the Silurian succession of Podolia is characterised by its cyclic pattern, with shallowing-upward cyclothems. In the traditional interpretation, the occurrence of stromatoporoid beds within each cyclothem marks the deepest (or most open-marine) sedimentary environment within the cycle. According to the results of recent studies, their occurrence is connected rather with a relatively shallow-water environment and with high energy phenomena. A substantial reinterpretation of the main sedimentary processes governing the deposition and facies distribution on the shelf is presented. Particularly, there are recognised and described high-energy sedimentary events repeatedly punctuating the generally calm sedimentation that prevailed in the lagoonal settings, some of which are interpreted as tsunami induced.Further perspectives for studies on the Silurian successions of Podolia are also discussed. The main problem is the precise correlation of particular sections that are scattered over vast distances and developed in similar facies associations.