New palynological data for Toarcian (Lower Jurassic) deep-marine sandstones of the Western Caucasus, southwestern Russia

Information on Jurassic palynomorphs from the Greater Caucasus is potentially of great importance, but its availability to the international research community is severely limited. New palynological data for Toarcian deposits of the Western Caucasus are recorded in the present paper. Particularly, dinoflagellate cysts are described for the first time from the Bagovskaja Formation; palynomorphs are found in sandstone levels within this unit. The most representative assemblage includes pollen (with predominant bisaccate pollen), spores (Cyathidites being commonest), and dinoflagellate cysts amongst which the predominant taxon is Nannoceratopsis spiculata. The dinocyst assemblage implies a late Toarcian age for the upper part of the Bagovskaja Formation. On the basis of these new palynostratigraphical results, the range of the formation is extended; previously, only the lower part had been dated on ammonite evidence

Kimmeridgian-Tithonian sea-level fluctuations in the Uljanovsk-Saratov Basin (Russian Platform)

Abstract The Uljanovsk-Saratov Basin, located in the southeast of the Russian Platform, presents an intriguing record of the Kimmeridgian-Tithonian sea-level fluctuations. In the Late Jurassic, this basin was a trough within the Interior Russian Sea. The data available from both outcrops and boreholes have permitted outlining a number of lithostratigraphic units and regional hiatuses in the northeastern segment of the Uljanovsk-Saratov Basin, thus permitting a precise reconstruction of transgressions/regressions and deepenings/shallowings. In total, three transgressive-regressive cycles and two deepening pulses have been established. These regionally documented changes were both related in part to global eustatic changes, and they also corresponded in part to the regional sea-level changes in some basins of Western Europe and Northern Africa, but not to those of the Arabian Platform. Differences observed between the global and regional curves as well as rapid Tithonian sea-level oscillations are explained by the influences of tectonic activity. It is hypothesized that the regional Tithonian oxygen depletion might have been a consequence from the rapid flooding of a densely vegetated land

Earth Science Frontier at Urban Periphery: Geoheritage from the Vicinity of Kazan City, Russia

Characterizing geological heritage sites (geosites) available in Russia remains an urgent task. The present study focuses on two geosites from the vicinity of Kazan—a large city on the Volga River. They are attributed to the standardized geoheritage types and scored by means of several criteria. It is found out that the Pechischi geosite represents nine geoheritage types, from which the stratigraphical type (stratotype section of the Upper Kazanian regional unit of the Guadalupian) and the geohistorical type (history of the Permian System studies) are the most important. This geosite reaches 675 out of 750 maximum possible scores, and it is ranked globally. The Cheremushki geosite represents six geoheritage types, from which the stratigraphical type (reference section of the Urzhumian regional unit of the Guadalupian) and the paleontological type (locality of diverse fossils, including tetrapods) are the most important. This geosite reaches a score of 250 and is ranked nationally. The undertaken study allows for recommending several actions for the effective conservation and exploitation of these geosites. The innovative interpretation is that the presence of geosites at the urban periphery makes its general (not only geological) heritage value comparable to that of the city’s center

Dispersed Geoheritage Points of the Lagonaki Highland, SW Russia: Contribution to Local Geoheritage Resource

Dispersed geoheritage points, which are small-sized and low-unique localities, manifest local geoheritage and, thus, may be useful for its comprehensive understanding. Field studies in the Lagonaki Highland (Western Caucasus, southwestern Russia) have permitted to find four geoheritage points that are described with argumentation of their importance to scientists, educators, and/or tourists. These points, none of which can be defined as a ‘traditional’ geosite, provide some precious sedimentary, palaeontological, and mineralogical information that improves perception of the local geoheritage landscape dominated by the Late Jurassic carbonate platform deposits. The studied localities are constituents of the local geoheritage resource because of their utility to three main categories of potential users. Scientists may be interested in these dispersed geoheritage points because of the need to collect massive geological data from big areas. Educators and tourists may appreciate these points because of their location along principal roads, i.e., their good accessibility

How global are the Jurassic–Cretaceous unconformities?

The reality of the global-scale sedimentation breaks remains controversial. A compilation of data on the Jurassic–Cretaceous unconformities in a number of regions with different tectonic settings and character of sedimentation, where new or updated stratigraphic frameworks are established, permits their correlation. Unconformities from three large reference regions, including North America, the Gulf of Mexico, and Western Europe, were also considered. The unconformities, which encompass the Jurassic-Cretaceous, the Lower–Upper Cretaceous and the Cretaceous–Palaeogene transitions are of global extent. Other remarkable unconformities traced within many regions at the base of the Jurassic and at the Santonian–Campanian transition are not known from reference regions. A correlation of the Jurassic–Cretaceous global-scale sedimentation breaks and eustatic curves is quite uncertain. Therefore, definition of global sequences will not be possible until eustatic changes are clarified. Activity of mantle plumes is among the likely causes of the documented unconformities

The human imprint on the unique geological landscape of the Western Caucasus

Human intervention in the geological environment is commonly thought to pose a threat to geoheritage. However, new information from the Western Caucasus where unique geological features are concentrated in Mountainous Adygeya, implies that man-made features in fact add value to geoheritage. Such features include a lengthy artificial niche in the Guama Gorge, accumulations of large artificial clasts along the road leading to the Lagonaki Highland and the Khadzhokh Quarry with the artificial Red Lake. These contribute to the regional uniqueness of geosites and can be classified as geomorphological, sedimentary, economical and hydro(geo)logical geoheritage types. Interestingly, these artificial features have natural analogues in the study area. Such integrity of local geological landscapes urgently require special interpretations for guided excursions and explanatory panels for correct comprehension of the origin of these unique features on the part of unprepared tourists. Generally, the human imprint on geological landscapes of Mountainous Adygeya is significant and occasionally positive, which makes the entire geodiversity hotspot of special, international interest and an object for further investigations

Geological activity of humans represented in the world heritage sites of India, Italy, and Russia: Evidence of the anthropocene

The idea of the Anthropocene attracts attention of scientists, policy-makers, and broad public to the geological activity of humans and poses new important questions for the modern stratigraphy. The growth of the Anthropocene-related knowledge and its promotion can be based potentially on the UNESCO World Heritage Sites (WHS). On the one hand, many of these sites provide spectacular evidence of the human activity. On the other hand, these are remarkable tourist attractions. The WHSs of three heritage-rich countries, namely India, Italy, and Russia, have been assessed with regard to how these reflect the geological activity of humans. It is established that 65-90% of all WHSs in each country provide direct and indirect evidence of such an activity (artificial caves, terrace building, etc.), which appears to be enough for the general discussion of the idea of the Anthropocene. However, the distribution of the WHSs by their age allows focusing only on the “early” (before 1800 AD) start of the Anthropocene, which is not enough for full discussion of the lower limit of this unit. The examples considered in the present study imply that some WHSs alone provide very important pieces of the Anthropocene-related knowledge

Geological activity of humans represented in the World Heritage Sites of India, Italy, and Russia: Evidence of the Anthropocene

The idea of the Anthropocene attracts attention of scientists, policy-makers, and broad public to the geological activity of humans and poses new important questions for the modern stratigraphy. The growth of the Anthropocene-related knowledge and its promotion can be based potentially on the UNESCO World Heritage Sites (WHS). On the one hand, many of these sites provide spectacular evidence of the human activity. On the other hand, these are remarkable tourist attractions. The WHSs of three heritage-rich countries, namely India, Italy, and Russia, have been assessed with regard to how these reflect the geological activity of humans. It is established that 65–90% of all WHSs in each country provide direct and indirect evidence of such an activity (artificial caves, terrace building, etc.), which appears to be enough for the general discussion of the idea of the Anthropocene. However, the distribution of the WHSs by their age allows focusing only on the “early” (before 1800 AD) start of the Anthropocene, which is not enough for full discussion of the lower limit of this unit. The examples considered in the present study imply that some WHSs alone provide very important pieces of the Anthropocene-related knowledge