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The abandoned gypsum quarry at Dingwall, in Canada, is a unique place with a peculiar “living” landscape created by expansive hydration of anhydrite process actively operating in the weathering zone at the quarry bottom. It causes a rapid volume increase of the rocks and the formation of the unique domed and tepee-like hydration landforms (several meters in length and up to 2.09 m high) with internal hydration caves (swelling caves, German: Quellungshöhlen). The quarry also shows some rare evaporite minerals, sulphate karst, spheroidal weathering of anhydrite and the other phenomena. Several steps of geoconservation strategy are described to promote Dingwall quarry as a geosite and a geodiversity site: inventory, quantitative assessment, conservation, interpretation, promotion and monitoring. The performed inventory describes the elements of the geoheritage. The quantitative assessment of the site, made according to the method by Brilha (Geoheritage 8:119–134, 2016), was based on the four aspects: scientific value, potential educational use, potential tourist use and the rate of destruction. For showing the geological heritage, the plan of the site was prepared, with paths for visitors, attendant infrastructure, thematic interpretation panels and plates with QR codes. As a part of the promotion, application of the Internet with already operating sites (e.g. hydrationcave.com) is proposed. In turn, monitoring, with measurements of benchmarks and photographic and photogrammetric documentation, will ensure the proper functioning of the site after establishing it as a geosite and a geodiversity site.

In the Dingwall gypsum quarry in Nova Scotia, Canada, operating in 1933–1955, the bedrock anhydrite deposits of the Carboniferous Windsor Group have been uncovered from beneath the secondary gypsum beds of the extracted raw material. The anhydrite has been subjected to weathering undergoing hydration (gypsification), transforming into secondary gypsum due to contact with water of meteoric derivation. The ongoing gypsification is associated with a volume increase and deformation of the quarry bottom. The surface layer of the rocks is locally split from the substrate and raised, forming spectacular hydration relief. It shows numerous domes, ridges and tepee structures with empty internal chambers, some of which represent unique hydration caves (swelling caves, Quellungshöhlen). The petrographic structure of the weathering zone has been revealed by macro- and microscopic observations. It was recognized that gypsification commonly starts from a developing network of tiny fractures penetrating massive anhydrite. The gypsification advances from the fractures towards the interior of the anhydrite rocks, which are subdivided into blocks or nodules similar to corestones. Characteristic zones can be recognized at the contact of the anhydrite and the secondary gypsum: (1) massive and/or microporous anhydrite, (2) anhydrite penetrated by tiny gypsum veinlets separating the disturbed crystals and their fragments (commonly along cleavage planes), (3) gypsum with scattered anhydrite relics, and (4) secondary gypsum. The secondary gypsum crystals grow both by replacement and displacement, and also as cement. Displacive growth, evidenced by abundant deformation of the fragmented anhydrite crystals, is the direct cause of the volume increase. Crystallization pressure exerted by gypsum growth is thought to be the main factor generating volume increase and, consequently, also the formation of new fractures allowing water access to “fresh” massive anhydrite and thus accelerating its further hydration. The expansive hydration is taking place within temperature range from 0 to ~30 °C in which the solubility of gypsum is lower than that of anhydrite. In such conditions, dissolving anhydrite yields a solution supersaturated with gypsum and the dissolution of anhydrite is simultaneous with in situ replacive gypsum crystallization. Accompanying displacive growth leads to volume increase in the poorly confined environment of the weathering zone that is susceptible to upward expansion.

The main lithological characteristics of the channel facies of the Susidovychi terrace, which correspond to the high (situated over the canyon) groups of Dnister terraces, were given. The investigations in the gravel pit at Kulakivtsi proved that the alluvium of the terrace has been formed in two stages. During the first stage, the lower 1.5 thick bed of the alluvium was deposited. The upper one, nearly 4 m thick alluvium bed was formed in the next, second one depositional stage. The stages of the alluvium formation were recorded in the changes of the granulometric and petrographical composition of the alluvium, and of the roundness of the coarse-grained clasts. The transition between these two alluvial beds is outlined by the voluminous intercalations of the sand lenses, and also by a change in the colour of the alluvial deposits. Granulometric composition of the alluvium of the channel facies, in general, changes little in the section. Only in the transition zone from the lower to the upper part of the alluvial deposits, there is a sharp, abrupt increase in the content of gravels and a sharp reduction in the content of boulders. Generally, in the composition of the alluvium two dominant and two subordinate components are clearly identified. The pebble grains and the sandy-clay matrix are the dominant components, whereas the gravel grains and the boulders are less common. Petrographic composition of the coarse-grained fraction of the terrace alluvium proved to be the richest of all the so far investigated sections of the high (situated over the canyon) terraces of the Dnister River (at Kunysivtsi, Ivane-Puste, Repuzhyntsi, and Lysychnyky). The pebbles 40–100 mm in diameter show particularly diverse petrographic composition which includes fragments of nine types of rocks: the four of the Carpathian provenance (sandstone, aleurite, cherts, and quartzite), and the five of the Podillian provenance (red-coloured Devonian sandstone, Albian cherts and sandstone, and lithothamnian and cryptocrystalline chemogenic limestone). More precisely, the richest is the lower part of the alluvial deposits where the fragments of all the nine rock types occur. The upper part of the alluvium is markedly poorer because only the five rock types occur there. Diversity of the petrographic composition of the alluvium decreased by reducing the local Podillian types of rocks, which are represented only by the red-coloured Devonian sandstones. The composition of the Carpathian types of rocks remained unchanged. The detected changes in the granulometric and petrographic composition of the alluvium of the investigated terrace permitted to show that the principal providers of the local (Podillian) debris of rocks was played by the Podillian tributaries of the Dnister River. The Dnister alone transported mainly the Carpathian material and only the small volume of Podillian rocks represented by the debris of the red-coloured Devonian sandstones. It was also found that the accumulation of the alluvial deposits of the Susidovychi terrace in the Kulakivtsi section took place in the conditions of restructuring of the Dnister palaeodrainage system. In the initial stages of this terrace formation, the palaeo-Dnister was directed from the village Dobryvliany further north than today, and it entered into the present-day Tupa River valley at environs of the village Bedrykivtsi. In the vicinity of the village Bedrykivtsi, the palaeo-Dnister was turning sharply eastward and proceeded along the present-day river valleys of Tupa and Seret. In the later stages of the Susidovychi terrace formation, the palaeo-Dnister left the portion of its valley stretching between the villages Bedrykivtsi and Schytivtsi, and it shifted several hundred meters to the south and has stopped practically within its current canyon valley. The desolate portion of its palaeo-valley located between the villages Bedrykivtsy and Kasperivtsi has been inherited by the Tupa River and the lower portion of this palaeo-valley located between the villages Kasperivtsi and Schytivtsi – by the Seret River. Key words: palaeo-Dnister, over the canyon terraces, Susidovychi terrace, alluvium, granulometric composition, petrographical composition, roundness, Carpathian material, Podillian material.

Studies of Miocene sediments in the Fore-Carpathian Basin, conducted by geologists from the University of Warsaw have provided new insights on the distribution of the facies infilling the basin, particularly in the forebulge and back-bulge zones. The origin of the large-scale sand bodies, evaporitic deposits and large-scale organic buildups is discussed, described and verified. These deposits originated in variable, shallow marine settings, differing in their water chemistry and the dynamics of sedimentary processes, and are unique with regard to the fossil assemblages they yield. Many years of taxonomic, biostratigraphic, palaeoecologic and ecotaphonomic investigations have resulted in the identification of the fossil assemblages of these sediments, their age, sedimentary settings and post-mortem conditions. Detailed studies were focused on corals, polychaetes, most classes of molluscs, crustaceans, echinoderms, and fishes.

The results of the investigation of the influence of the microclimatic conditions on the weathering (hydration) of anhydrite and the formation of gypsum domes and caves from swelling of the anhydrite beds in the Pisky quarry are presented. The whole day synchronous measurements of temperature and humidity, with an interval of 15 minutes, were conducted in the selected points within the gypsum-anhydrite domes (inside the caves), in the vicinity of the domes, and in the variable sites of the stone pit, with the use of the automatic electronic recording devices. The values of temperature and humidity from 15 representative sites, recorded during the stable hot weather conditions, have been analysed. The average diurnal and extreme values, and the diurnal run of the temperature have been shown on the graphic drawings. The reasoning has been made about the dependence of the gypsum domes and caves formation on the conditions of availability of the water; the water from precipitation, the ground water, the water running down the slopes, and the condensation water. It has been pointed out that microclimatic conditions influence the development of gypsum domes and caves from swelling of the anhydrite beds through the condensation of water onto the anhydrite bed in the conditions of aspiration of the humid air through the caves. Key words: gypsum domes, caves from swelling of the anhydrite beds, anhydrite rocks, hydration, gypsum, microclimatic conditions, condensation of water vapor.

In the quarry at Pisky, 30 km south of Lviv, due to weathering (hydration) of anhydrite (CaSO4), and its transformation into gypsum (CaSO4•2H2O) the volume of the rock increases and the unique forms of relief form called the hydration domes. In the interiors of the growing domes chambers are formed that gradually transform into the caves called the hydration caves (or the swelling caves). At the same time the rocks dissolve and their surface is covered with rillenkarren. The unusual weathering and geomorphological processes taking place today require the accurate documentation and monitoring. In this paper we describe the optimum field methods used to document the zone of weathering. These methods include: method of benchmarks, method of 3D laser scanning, method of scanning with structured light LED, method of terrestrial photogrammetry, and the method of modelling of 2.5D objects using photogrammetry. We discuss the advantages and disadvantages of the methods used.

The Miocene of the northern part of the Polish Carpathian Foredeep contains a record of events particularly important in the evolution of the Central Paratethys Basin. There, the Paratethyan Badenian Salinity Crisis resulted in the deposition of evaporite gypsum deposits of the Krzyzanowice Formation. The ensuing post-evaporite marine Badenian deposition is recorded by the marly Pecten Beds. The transition to the overlying clays of the Syndesmya Beds represents the initial deterioration of normal marine conditions within the basin, and is associated with the disappearance of typical stenohaline faunal components during the Badenian–Sarmatian Extinction Event, and the subsequent appearance of endemic Sarmatian taxa. The history of these Paratethyan events has hitherto been only poorly dated. New 40Ar/39Ar dating of biotite and volcanic glass from a rhyolite tuff within the Pecten Beds (Babczyn-2 core) constrains its depositional age to 13.06 ± 0.11 Ma. This age suggests that the faunal extinction presumably took place after 13.06 ± 0.11 Ma, and that the salinity crisis ended before then. This result is consistent with other reliable radiometric age constraints that collectively suggest that the crisis began shortly after 13.81 ± 0.08 Ma ( de Leeuw et al., 2010 ), and that evaporite deposition took place ca. 13.60 ± 0.07 Ma ( de Leeuw et al., 2010 ). Both the Badenian evaporites and the Pecten Beds in Carpathian Foredeep are thus Serravallian in age and represent the lower part of Neogene Nannoplankton Zone 6 (NN 6).

Microbialite deposits are considered as a product of the interactions between activity of benthic microorganisms and physicochemical properties of environment. Activity of currents is one of the most important physical processes influencing the accretion of microbialite domes. The domes growing in current-swept areas usually show elongated shapes parallel to the dominating water flow direction.