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Moraine failures are severe events in proglacial areas that lead to major surface changes. On July 1, 2015, a lateral moraine collapsed within the 9.1 km2 glacierized Djankuat Catchment in the Northern Caucasus. This study quantifies the surface changes over a 7-year period after the collapse and proposes the main event triggers using hydrometeorological measurements and remote sensing data. Digital Elevation Models (DEMs), derived from Unmanned Aerial Vehicle (UAV) surveys and satellite images for the 2010–2022 period, were used to estimate erosion/deposition associated with the event and further surface changes in several zones: the breach, the fan, the headward erosion area and gully erosion on lateral moraine slopes. The failure occurred due to an extreme precipitation event (7-day cumulative sum: 227 mm, 24 h prior: 60 mm), simultaneous snowmelt within the whole upstream catchment, and continuous positive temperatures. During the 2015 event, approximately 200,000 m3 of material was instantly eroded, corresponding to a surface lowering of 1.91 m a−1 (over 52,227 m2). Only 25 % of the eroded material redeposited on the fan. Later in 2017–2019, the breach underwent infilling with a 10 m deposition layer in the bottom (net change ca. 14,600 m3), while the stream in the headward erosion area continued to incise (ca. −12,900 m3). From 2019 to 2022, the dynamics decreased, and a positive sediment budget was assessed for all zones except the intensive local erosion on the fan in 2021–2022 (ca. −15,200 m3). Gully changes suggested a constant erosion of 90–100 mm a−1. Based on daily rainfall measurements for the 2008–2022 period, we proposed a 3-day and prior 15-day cumulative precipitation threshold that outlines major erosional events in the Djankuat River valley. A cumulative 3-day precipitation of 100 mm could be a sufficient but not necessary condition since some significant sediment export was recorded below that threshold. • Surface changes due to the moraine failure in the Caucasus were quantified. • The main factors are rainfall, simultaneous snowmelt, and high temperatures. • Deepening caused headward erosion of a new channel, followed by stabilization. • Snowmelt only is not enough to initiate significant erosion. • Erosion-deposition processes occur when the 3-day rainfall exceeds 100 mm. [ABSTRACT FROM AUTHOR]

This paper describes the modelling of suspended sediment yield in a plains region in the European part of Russia (EPR) and its prediction for ungauged catchments. The studied plains area, excluding the Caucasus and Ural Mountains, covers 3.5 × 106 km2 of the total area of about 3.8 × 106 km2. Multiple regression methods, such as a generalized linear model (GLM) and a generalized additive model (GAM), are used to construct the models. The research methodology is based on a catchment approach. There are 49,516 river basins with an average area of about 75 km2 in the plain regions. The suspended sediment yield geodatabase contains data from 385 gauging stations. The linear GLM model of suspended sediment yield explains about 50% and the GAM model about 65% of the data variability (R-squared adjusted). The models include mean slope steepness, percentage of arable land, runoff per unit area, catchment area, soil rank and catchment soil erodibility as significant predictors. They also include a zonal-sectoral gradient (the sum of active temperatures and the standard deviation of air temperature, or directly by geographic coordinates). A GAM model is trained to predict suspended sediment yields for unexplored areas of the area. The paper presents the results of extrapolating suspended sediment yield values to ungauged river basins in a plains region of the EPR. For the first time for such a large area, the models built and the use of the basin approach made it possible to predict runoff values for hydrologically unexplored river basins. [ABSTRACT FROM AUTHOR]

• Suspended sediment fluxes of a small glacierized catchment in the Caucasus were evaluated. • An exceptional erosion event changed the sediment dynamics. • The proglacial area with buried ice is the main sediment source during non-rainy days. • About half of the annual sediment fluxes moved during high runoff events. Suspended sediment yields from glacierized catchments are often among the highest in the world, and their sediment dynamics can be highly variable. This study was undertaken in the 9.1 km2 glacierized catchment of the Djankuat River located in the Russian part of the Northern Caucasus. The outlet of the study catchment is a hydrological gauging station located at an altitude of 2635 m a.m.s.l. ('N43°12′31.71″, E42°44′05.93″). The catchment includes a temperate valley glacier (area = 2.42 km2) and three smaller hanging glaciers, several moraine deposits, rock walls, and a large and expanding proglacial area. The main goal of our study was to assess the impact of an exceptional erosion event on 1st July 2015 (with an annual exceedance probability of less than 0.1%) on suspended sediment yields and the relative contributions of various sediment sources The work combined direct suspended sediment discharge measurements at the gauging station during five ablation seasons (2015–2019) with geomorphic mapping techniques based on detailed field observations and sediment source fingerprinting. Results show that mean annual suspended sediment yields reached 1118 t km−2 year−1 which is one of the highest measured estimates for any of the glacierized mountain rivers globally. About half of the annual suspended sediment flux was exported during a limited number (1–12% of the annual events) of extreme hydrological events. The sediments mobilized by bank and riverbed erosion within the new lower reach of a tributary channel which appeared after the breakthrough of a lateral moraine became the primary sediment source. It contributed over 50% of the suspended sediment on days with extreme rainfall. Contributions to the suspended sediment load from the glacier source were event-dependent and were only dominant (c. 60–70%) in the upper reaches of the proglacial area (first 800 m). The proglacial part of the study catchment with buried ice was the main sediment source (79%) during non-rain days. [ABSTRACT FROM AUTHOR]

Exploration efforts around the Greater Caucasus region started towards the end of the 19th century and established a wide range of petroleum play types in various basin segments around the orogen. All these plays are associated with the flanks of the inverted thrust‐fold belt and the adjacent foreland basin systems, but display significant variation among the basin segments depending on the tectonostratigraphic units involved and the degree of exploration maturity. Whereas the same main source rocks have generated most of the hydrocarbons in all the basins (namely organic‐rich shales in the Oligocene – Lower Miocene Maykop Group and the Eocene Kuma Formation), it is primarily the trapping style, both proven and speculative, which is responsible for the broad spectrum of play types observed. Eleven play type diagrams across six main petroleum provinces of the Greater Caucasus region are presented in this paper and summarize the current exploration understanding of the existing discoveries and potential new play targets. These play cartoons offer a prospect‐scale summary of both mature producing and underexplored basin segments in a coherent visual manner, and are therefore intended to promote future exploration efforts in the Caucasus region. The testing of new play types requires the proper risking of the two most critical elements in the region: hydrocarbon kitchen effectiveness, and post‐charge trap modification. The de‐risking of these factors will require properly designed, fit‐for‐purpose acquisition of modern geological and geophysical data sets. [ABSTRACT FROM AUTHOR]

Strong seasonal variations in the radon exhalation rate from the soil surface were revealed during a two-year monitoring cycle in a fault zone on a slope of Mount Beshtau in the Caucasus Mineral Water Resort area, Russia. The variations are characterized by very high radon levels in summer and low levels in winter. In the warm season (from late April to early October), the radon exhalation rate values ranged from 4.5 to 23.8 Bq m–2 s–1. During the cold period (from November to March), the radon levels decreased to 0.04–0.17 Bq m–2 s–1. A strong correlation was found between the radon exhalation and atmospheric air temperature (the Pearson correlation coefficient is 0.8). The simulation results show that seasonal fluctuations in the radon exhalation rate are caused by an inversion of the convective radon transport direction in the fractured zones of the rock massif. In summer, the convective flow of radon is directed from the rock massif to atmosphere, whereas this flow in winter comes from the atmosphere to rock massif. The rate of convective transport varies from 5 to 28 m day–1 during the warm season and from –2 to –4 m day–1 during the cold one. Seasonal radon anomalies in fault zones are most probably caused by thermally induced convective air flows in the highly permeable rock zone due to the temperature difference between the rock air and atmospheric air. Seasonal radon anomalies should be taken into account both when mapping radon risk and when using radon as a tracer of gas transport in geochemical and geophysical research. [ABSTRACT FROM AUTHOR]

Abstract—Tengmalm's Owl (Aegolius funereus caucasicus But.) inhabits dark coniferous, pine, and deciduous forests in the mountains of the North Caucasus in the range from the city of Tuapse in the west to Inner Dagestan in the east, rising to pine forests to a height of 1900–2000 m above sea level. During its winter wanderings, it occasionally occurs in the foothills, but almost does not go out to the piedmont plains. Winter records in the steppe regions of Ciscaucasia may refer to nomadic specimens of a nominate subspecies (A. f. funereus L.), which is common in Voronezh oblast and in northern Rostov oblast. The bird finds the most optimal conditions in old dark coniferous and mixed forests of the Western Caucasus, and its maximum abundance is noted in the Teberda Nature Reserve (1 pair/10 km2). In the Central and Eastern Caucasus, it lives in old deciduous forests (mountains with a low elevation) and in pine forests (mountains of average height). The population of Tengmalm's Owl in the North Caucasus is considered relatively stable, and its total number is now estimated at 1000–2000 pairs, including 200–400 pairs living in Karachaevo-Cherkessia and 20–30 pairs living in Adygea. Tengmalm's Owl is ecologically closely connected with the Black Woodpecker (Dryocopus martius), whose old hollows it usually nests in. The birds display from January to May, but most actively in mid-April. In late April, they lay eggs and fledglings appear in June–July. [ABSTRACT FROM AUTHOR]

The authors highlight relatively unknown efforts at local civil society building and conflict management in the North Caucasus. They feature a report that surveys activities with youth and with elders' councils, in the republics of Chechnya, North Ossetia-Alania, Kabardino-Balkaria, Dagestan, and Ingushetia. [ABSTRACT FROM AUTHOR]

This paper discusses the joint impact of catchment complexity in topography, tectonics, climate, landuse patterns, and lithology on the suspended sediment yield (SSY, t km−2 year−1) in the Caucasus region using measurements from 244 gauging stations (GS). A Partial Least Square Regression (PLSR) was used to reveal the relationships between SSY and explanatory variables. Despite possible significant uncertainties on the SSY values, analysis of this database indicates clear spatial patterns of SSY in the Caucasus. Most catchments in the Lesser Caucasia and Ciscaucasia are characterized by relatively low SSY values (<100–150 t km−2 year−1), the Greater Caucasus region generally have higher SSY values (more than 150–300 t km−2 year−1). Partial correlation analyses demonstrated that such proxies of topography as height above nearest drainage (HAND) and normalized steepness index (Ksn) tend to be among the most important ones. However, a PLSR analysis suggested that these variables' influence is likely associated with peak ground acceleration (PGA). We also found a strong relationship between land cover types (e.g., barren areas and cropland) and SSY in different elevation zones. Nonetheless, adding more gauging stations into analyses and more refined characterizations of the catchments may reveal additional trends. [ABSTRACT FROM AUTHOR]