Cave mapping represents one of the most complex challenges in geomorphological cartography, as it must convey the true three-dimensional geometry of subterranean spaces such as overlapping passages, irregular cross-sections, and variable ceiling and floor morphologies, within a two-dimensional framework. This study examines the methodological and interpretive challenges of cave mapping, utilizing the Gamssteighöhle cave in the Austrian Alps as a case study. During the 11 years of exploration, over 10 km of passages were surveyed using the DistoX vector survey method. Yet, the complex morphological forms necessitated deviations from the standard symbology recommended by the International Union of Speleology. Several key visualization challenges are analyzed, including subvertical pits, overlapping passages, and 3D maze-like networks. Solutions such as multiple projection planes, transparency effects, perpendicular cross-sections, and splitting maps into separate sheets are proposed to maintain readability and spatial context. We evaluate traditional vs. LiDAR-based mapping, concluding that while dense 3D point clouds offer exceptional precision, they do not inherently yield readable or informative maps. Cartographic generalization, with its interpretative input of the cartographer, remains indispensable for transforming spatial data into coherent and communicative cave maps. LiDAR and photogrammetry greatly enhance visualization and quantitative analysis but complement rather than replace traditional mapping.

The Giant Geode of Pulpí is a unique mineralogical phenomenon worldwide, remarkable for its large selenite gypsum crystals. Its recent development as a tourist site and inclusion on UNESCO’s Tentative World Heritage List, highlight the need to assess the impact of visits on its conservation. This study investigates airborne particle dynamics inside the Geode, focusing on tourist activity and natural ventilation. We measured deposition rates and composition of airborne particles using passive traps and a continuous laser-optical particle counter. Microenvironmental variables linked to ventilation, such as temperature and radon gas concentration (²²²Rn), were simultaneously monitored. Results show a predominance of fine particles (<5 >μm), which remain suspended longer and penetrate deeper into the cavity. Coarse particles (>5 μm) settle quickly, mainly near the Geode entrance. Chemically, most particles correspond to autochthonous mine minerals (celestine, siderite, quartz, and gypsum), though allochthonous materials such as non-mineral fibers introduced by visitors were also identified. Natural ventilation strongly influences particle behavior. Fine particle concentrations (<5 >μm) rise (i.e., up 30×103 particles/L) when the renewal of air with the exterior, characterized by lower suspended particle concentrations, is restricted. Under these conditions, the particle remobilization induced by visitors causes a higher accumulative effect of fine particles in the mine-Geode atmosphere. Autochthonous mining debris and dust is the main source of coarse particles, with concentrations peaking during visiting hours due to resuspension by tourist movement, up to 2,000 particles/Lfor 5-10 mm particles and up to 400 particles/L for >10 mm. These findings provide a foundation for preventive conservation strategies. Adapting visitor pathways and access protocols could reduce particle resuspension and deposition, helping preserve the exceptional crystals of the Geode of Pulpí for future generations.

The water-film that coats cave walls and speleothems is a key player for the regulation of cave microclimate and the control of speleothem growth. In this paper, we demonstrate the capability of a confocal optical sensor to quantitatively measure on-site the rapid variations of water-film thickness when dripping, active condensation, or dryness occur on walls of various caves. Results obtained from a sample of four prehistoric caves and one stalagmite cave from Southwest France, indicate that the measurable thickness of water-films is generally in the 25-70 µm range for cave walls and reaches 200-300 µm on the horizontal plane of active speleothems. The high measurement frequency enables the monitoring of water-film dynamics for a few minutes, especially the tracking of thickness changes triggered by drop dripping and water flow. The optical sensor appears to be a promising tool for the conservation of prehistoric caves facing subsurface warming.

Near Snail Shell Cave in central Tennessee, USA, seven image interpreters independently mapped lineaments using a 3DEP LiDAR DTM, revealing geomorphic and structural differences in and near different parts of the cave. MANOVA comparison of lineament and cave passage trend for Western, Central, and Eastern Snail Shell caves reveals statistically significant differences (p < 0.05). The Western cave (mean depth 44 m) is in the gently-dipping limb of the Snail Shell anticline, and the Central cave (mean depth 31 m) is in the anticline hinge. In contrast, many Eastern cave passages (mean depth 40 m) cut across the anticline hinge and part of the limb of the Overall syncline. For both the Western and Central caves, a post-hoc Tukey’s HSD test fails to show that lineament trend within 235 m of the cave differs significantly from passage trend, and the test fails to show that the two differ significantly within 235 and 433 m of the Eastern cave. Additional statistical testing fails to show a difference between Western passage trend and bed strike, indicating the likelihood that lineaments and passages developed within strike-joints. However, testing shows a statistically significant difference between passage trend and bed strike for the Central and Eastern caves. The strike of joints inside the Eastern cave shows that it is within a joint zone which penetrates to depths of at least 80 m and is expressed at the surface as an ~4.2 km-long belt of elevated lineament line density. The lack of a statistically significant difference between Eastern passage trend and the trend of a nearby topographic escarpment suggests that many joints are stress release fractures formed during relatively recent erosion. For the Eastern cave, intersections between lineaments and structures would be attractive targets for groundwater exploration at depths typical of wells in carbonates.

We redefine the extent of former glaciers in the northern Jura Mountains through the study of endokarst deposits. Sedimentary deposits (pebbly debris flows, laminated clays, and allochthonous limestone blocks) and chemical deposits (speleothems) were identified and studied using three complementary approaches: (i) detailed geomorphological mapping, (ii) petrographic analysis, and (iii) U/Th-dating. In addition, a surface geomorphological analysis made it possible to calculate the minimum erosion time required for the formation of the sinkhole linked to the underground study site. The study site is the Dolois Chamber, an underground site upstream of the Verneau karst network (Doubs Department, France). The combined results aided in reconstructing the chronology of the various events affecting the study site, including 1) formation of the Baume-des-Crêtes paleo-sinkhole a few hundred thousand years (during Marine Isotope Stage (MIS) 8); 2) invasion by a pebbly debris flow, probably linked to a mid-Pleistocene glacial periods (MIS 8 or 6); 3) hydrological dysfunction, including significant flooding and deposition of laminated clays; 4) capture of the paleo-sinkhole by the Biefs-Bousset active sinkhole approximately 10 kyr (MIS 2); and 5) a recent return to water level variations of approximately 10 m during flooding. Furthermore, our results show that the extent of the ice cap in the Jura Mountains during the mid-Pleistocene (MIS 8-6) probably did not reach beyond the topographic high of the Salinois Fault Zone at the plateau margin.

Fires occurring in cave guano are a rare and unusual phenomenon and the occurrence of such events in Southeast Asia is particularly novel. In this study, we document the first recorded instance of a bat guano fire in a tropical cave at Tham Chao Ram in Sukhothai province, northern Thailand. A bacteriological analysis was made of the guano at the fire site and from a control site within the cave. We give a comprehensive review of global reports on bat guano fires in caves, conduct an initial investigation of the physical factors at the fire site and discuss the potential causes of such fires. Additionally, we discuss the implications for guano cave management and decision-making in relation to cave guano fires. This report emphasizes the need for further research into the conditions that lead to guano fires, their ecological impacts and the development of effective management strategies to prevent or mitigate such incidents in cave environments.

Exposure to radon and its progeny poses a significant health risk for workers in tourist caves. Implementing protective measures is challenging due to increasingly strict gas concentration and dose limits in new regulations. This study evaluates the annual effective radiation doses received by workers and researchers, considering seasonal and spatial radon variability. Radon levels, temperature, and ventilation patterns were continuously monitored for at least one year in each cave. Results show significant radon fluctuations influenced by seasonal ventilation regimes driven by thermal gradients between the cave and external atmosphere. Using International Commission on Radiological Protection guidelines, the study calculates the maximum allowable working hours to comply with European and Spanish regulations, which set an annual dose limit of 20 mSv for occupational exposure. Findings emphasize the necessity of continuous radon monitoring and tailored management strategies, such as adjusting work schedules and restricting access during high-radon periods. Additionally, the study highlights the limitations of passive radon detectors, which tend to underestimate actual radon levels compared to continuous monitoring. This research provides a protocol for managing radon exposure in culturally significant caves while ensuring worker and visitor safety. The methodology includes initial spatial dosimetry, continuous monitoring, and safe working hour recommendations based on monthly radon levels. Monitoring should also consider parameters like temperature, humidity, and CO₂ to understand ventilation dynamics. These measures are essential for compliance with radioprotection standards while preserving the integrity of these unique cultural and historical sites.

Stalagmites are invaluable archivers of past climate conditions, as their oxygen isotopic composition (δ¹⁸Oc) closely mirrors the isotopic signature of the drip water (δ¹⁸Ow) from which they precipitate. This isotopic relationship is governed by the fractionation factor (1000ln¹⁸α), which is temperature dependent. In this research, we studied 1000ln¹⁸α within Cueva Ensueño, a cave situated in Puerto Rico’s northern karst region, as a step toward calibrating δ¹⁸Oc for paleoclimate interpretations using stalagmites. We collected drip waters, measured their temperature in situ, and sampled carbonates from ten selected stations within the cave. Sampling was conducted in December and May, representing months of the dry and wet seasons, respectively. To better understand isotopic variations in stalagmites, we farmed calcite at the same drip sampling locations during both seasons. Our findings reveal a seasonal bias in isotopic fractionation of farmed carbonates at Cueva Ensueño, with higher 1000ln¹⁸α values in May (30.7–32.7) and lower values in December (27.8–29.7), but when these values are averaged, they merge towards the isotopic fractionation of the shaved stalagmites. We also found that stable isotope transfer into the cave is delayed, which could be due to epikarst storage effect and piston flow recharge, with the May drip water likely affected by moisture recycling before reaching the cave (as shown by the high d-excess values). In contrast to stable isotopes, the drip elemental composition suggests an immediate prior calcite precipitation response, which could be evidence of a dual transfer process. This research illuminates our understanding of oxygen isotope fractionation, which is useful for paleoclimate reconstructions and can provide insights into similar settings in the region.

This study presents the results of a long-term investigation of the microclimatic conditions in Shulgan-Tash Cave (Southern Urals, Russia), which hosts the largest assemblage of Upper Paleolithic paintings (ca. 16.3–19.6 ka) in Eastern Europe. The cave exhibits two distinct seasonal ventilation regimes – winter and summer – differentially influence its two levels of galleries. In the Lower Level, which contains 83% of the images, near-atmospheric CO2 concentrations persist year-round, and temperature variations associated with seasonal infiltration events are minimal (1.0–1.3°C). By contrast, the Upper Level, including the decorated Hall of Paintings, is affected by downdrafts of CO2-rich air during summer, resulting in elevated concentrations (up to 0.2–0.3% vol.). These conditions reflect the position of this sector beneath a densely forested massif and the degassing of phreatic waters. The principal threats to the preservation of the cave art include: (i) summer condensation, mitigated by the use of air-circulation screens; (ii) cyclic CO2 fluctuations, which drive alternating dissolution and degassing in water films on decorated walls; and (iii) rapid degassing of infiltrating waters, leading to calcite deposition over the paintings. These processes variably affect the decorated chambers, highlighting the need for site-specific conservation measures. Given the cave's recent inscription on the UNESCO World Heritage List, these findings provide an essential basis for developing effective long-term preservation strategies for this unique cultural heritage site.