(1) Background: Show caves are unique natural attractions and touristic traffic can trigger their degradation within a very short time. There are no universal solutions to counter the effects of the touristic impact upon cave environment and both protection protocols and management plans have to be established on a case-by-case basis; (2) Methods: The study includes four show caves from the Romanian Carpathians, where monitoring of the number of visitors, paralleled by the monitoring of the main physico-chemical parameters of the air and water (CO2, temperature, humidity, drip rate, conductivity, and pH) was implemented; (3) Results and Conclusions: The results of the study has: (i) established a monitoring protocol to be applied to each of the four show caves; (ii) established a set of basic principles to be enforced by the management of show caves; (iii) issued a set of preventive measures and instructions to be followed by the personnel and stakeholders of the caves.

The region of Eastern Europe & Turkey contributed to the SISAL (Speleothem Isotopes Synthesis and AnaLysis) global database with stable carbon- and oxygen isotope time-series from 18 entities from 14 cave systems. The currently available oldest record from this region is the ABA-2 flowstone record (Abaliget Cave; Hungary) reaching back to MIS 6. The temporal distribution of the compiled 18 entities points out a ~20-kyr-long period, centering around 100 ka, lacking speleothem stable isotope record in the region. The regional subset of SISAL_v1 records displays a continuous coverage for the past ~90 kyr for both δ¹⁸O and δ¹³C, with a mean temporal resolution of ~12 yr for the Holocene, and >50 yr for the pre-Holocene period. The highest temporal resolution both for the Holocene and the pre-Holocene was achieved in the So-1 record (Sofular Cave; Turkey). Assessing the data, an important split was found regarding the climatic interpretation of speleothem δ¹⁸O. While the oxygen isotope composition of more continental formations is thought to reflect mainly temperature variations and changes in moisture transport trajectories, it may strongly reflect fluctuations of precipitation amount in the southern part of the region. Variations of δ¹³C primarily interpreted as humidity changes reflecting dry/wet periods across the region. Elevation gradients from three non-overlapping time periods from the region - for the last 5kyr - indicated systematically prevailing elevational gradients around -0.26‰ 100m^-1 in δ¹⁸O. The regional comparison of SISAL_v1 speleothem δ¹⁸O and the temporal distribution of coarsely crystalline cryogenic cave carbonate occurrences back to 45ka does not appear to confirm the finding that occurrence of the latter coincides with the warming from stadial to interstadial conditions.

Two strongly curved areas of the Carpathians in Romania are earthquake-prone: Vrancea - in the South-Eastern Carpathians, and Danubian – in the western edge of the Southern Carpathians. By far the highest seismicity episode in 2023 was recorded in the Southern Carpathians, near Targu Jiu city, of more than 4000 earthquakes. A first ML 5.2 mainshock was recorded on 13 February, followed by a second one, ML 5.7, on 14 February. Our purpose is to provide a first analysis of this sequence in order to explain its extent and unusual development, in time. The possible role of fluids in the middle crust, is discussed in connection with the rather unusual character of the space-time distribution of aftershocks. A large and high-quality dataset is provided by the dense array of seismic stations which has been gradually improved by adding new stations in the epicentral area. The thorough revision of the phase picking and location reveals a few interesting and intriguing features of seismicity that still remain worthy to be further investigated. The database built within this paper provides excellent information not only for Targu Jiu area, but for any other investigation in intra-continental regions characterized by diffuse and sporadic seismic activity.

A notable REE mineralization in Europe is associated with the Ditrău Alkaline Massif (DAM) in the Eastern Carpathians (Romania). It is an expression of the latest hydrothermal phase in the DAM and is found in the form of mineralized carbonate veins cross-cutting the complex in the NW (Jolotca region) and the SE (Belcina region) parts of the DAM. In the Belcina veins monazite-(Ce), xenotime-(Y), apatite, together with Fe-Mg-rich carbonate, thorite, thorogummite, gedrite and plagioclase are rock-forming. Three different textural and chemical types of the monazite-(Ce) and the xenotime-(Y) document a three-stage evolution. The relative phosphate age succession (from older to younger) thereby is xnt1 > xnt2 (>)+ mnz1 + Fe2O3 + Fe-gedrite > mnz2 + Fe-dolomite (+ plagioclase) > mnz3 + xnt3 + apatite. Phosphate chemistry shows that these crystallized from hydrothermal fluids, whereby each phosphate type follows a separate evolutionary path recommending growth from (at least) 3 independent and successive hydrothermal fluids. Chemistry and pathways within the DAM suggest that these hydrothermal fluids could be derived from a subsurface carbonatitic intrusion. Mnz1,2 and xnt1,2 ages are tightly cluster at 215.8 ± 0.7 Ma (Norian, Upper Triassic). The third-generation phosphate ages are younger, but associated with large analytical uncertainties and did not deliver geologically useful ages. The mean age of ca. 216 Ma is interpreted as timing the Belcina REE mineralization, what together with the fluid chemistry, supports a model of the presence of a late-stage, independent carbonatitic intrusion about 10 Ma after the main igneous activity (ca. 235 - 225 Ma) forming the DAM, synchronous with extension-related magmatism in the region.