Search in KarstBase
![]() |
![]() |
The genesis of the largest gypsum caves in the world and their hydrogeologic role are considered. The caves are developed in the Neogene sequence of the southwestern outskirts of the Volyno-Polilsky artesian basin. Four evolutionary-stadial settings of the formation of groundwater of the Miocene thickness are distinguished. It is found that the large maze cave systems in the gypsum are formed under conditions of a confined aquifer system due to dispersed recharge from a basal aquifer, under general ascending circulation through the gypsum layer. The general and regional models of artesian speleogenesis are elaborated, based on the ideas about substantial role of transverse percolation through dividing layers in multi-layer artesian systems and inversion of hydrogeological function of components of the geo-filtration section during speleogenesis. The conceptions about structure and evolution of groundwater circulation in the Miocene aquifer system, as well as related concepts on speleogenesis in the gypsym, constitute a new basis for solving a number of practical problems of region hydrogeology, engineering geology, geochemistry and environment.
In Russian and Ukrainian, with abstract in English
Most of exogenous epigenetic sulphur deposits are clearly associated with intensely karstified carbonate and sulphate rocks. This paper demonstrates, using the Pre-Carpathian region as an example, that karstification is one of the most important processes guiding the formation of sulphur deposits. This is determined by a coincidence of some major prerequisites of these two processes.
In the Podol’sky and Bukovinsky regions the Miocene aquifer system is well drained by erosion valleys; the giant network caves known here in gypsum formed under past artesian conditions. In the region of sulphur deposits, associated with the same karstified gypsum strata, true artesian conditions still prevail. Hydrogeologic data show that abundant cavities detected in the vicinity of sulphur deposits can be interpreted as having the same origin as the relict caves of the Podol’sky and Bukovinsky regions. The widespread belief that the gypsum/anhydrite bed in the region is an aquifuge separating the Miocene aquifers is inadequate. This belief caused much controversy with regard to the genetic interpretations of sulphur deposits in the region. Cave systems formed by the upward water flow through the gypsum/anhydrite bed govern the water exchange between the aquifers within the aquifer system.
A new karst model for the formation of sulphur deposits is suggested. It agrees well with the hydrogeological features of the Miocene sequence and with biogeochemical mechanisms of sulphur origin in low-temperature diagenetic environments.
A review of the book: Klimchouk, A.B. Hypogene Speleogenesis: Hydrogeological and Morphogenetic Perspective
In March 2007 there was a 30th anniversary of a discovery of the Zoloushka (Cinderella) Cave, which is one of the largest gypsum caves in the world. Until now over 90 km of passages of a total volume of 0.65 million m3 have been mapped. The cave was accidentally encountered by the face of a gypsum quarry in 1946, but it was not penetrated by speleologists until 30 years later. From the very beginning of exploration, the cave attracted the attention of many speleologists and later - geographers and geologists. It became a notable supplement to the family of the largest gypsum caves, which were investigated in the area of the neighboring Podolsky (Podolia) region. It appeared however not entirely similar to them: as compared to the cave systems in Podolia the Zoloushka Cave shows more voluminous passages and it is more filled with clayey sediments. The cave passages developed mainly in the upper part of the gypsum layer, which resulted in collapses in many sections. The main feature of the Zoloushka Cave is that it was artificially uncovered (in the quarry face) and it was not accessible until the gypsum layer was drained by pumping out karst water. The quarry exposed rich groundwater reservoir ? a large karst aquifer. Gradual deepening and extension of the quarry caused the increase of outflow rate and the increase of water withdrawal. In the late 1960s, when the most (18-20m) of the gypsum layer (total thickness 24-26 m) was entrenched, the karst system had been already drained. Groundwater, marking the surface of a depression cone, was preserved only in the lowest parts of the cave. The karst system became accessible to investigations. Opening of the Zoloushka maze had interrupted the natural evolution of the hydrogeological settings ? it had occurred in the moment when it was almost totally filled with water. The caves in the Podolia region underwent this stage tens of thousand years earlier. Modern draining and younger age of the Zoloushka Cave determined a specific character of its internal relief (increased moisture of deposits, lack of secondary gypsum formations which are so typical for the Pololian?s caves), and caused different processes to operate (roof subsidence, sediment drying/draining, water flows between different areas, etc.), which accompanied a sudden conversion from water-filled chambers to empty ones. It became clear from the very beginning that the cave is an extremely interesting object from a scientific point of view. The cave provided a unique opportunity to carry out multi-aspect investigations. Many phenomena and features were observed by speleologists for the first time. Morphological features of the cave, such as large cylindrical pits created by rising underground water, evidence undoubtedly a confined origin of the cave system. The morphogenetic studies in the cave have played an important role in understanding problems of karst development in this region and establishing a new (artesian) regional concept of speleogenesis. The abundance of iron-manganese deposits in the cave attracted the attention of geochemists, who determined the presence of numerous geochemical processes which occurred when the cave became drained. The cave made it possible for speleologists to study the mechanisms of sinkhole development, which is extremely important for an adequate understanding and assessment of karst hazards. The cave sediments contain numerous carbonate insertions (lithified fills of relict fissures in gypsum), which make it possible to reconstruct important palaeogeographic, palaeotectonic and palaeokarstic events. During all these years the cave has been well studied. This work represents a kind of summary of all the hitherto achievements and has a general and complex character. Many problems however remained unresolved. Therefore the aim of this work is not only to present general results of the investigations which have been carried out in the Zoloushka Cave, but also to attract the interest of specialists of different fields in order to enlarge and intensify the investigations in the cave itself and its surrounding. The book's twelve chapters deal with history of the cave discovery and study, natural conditions and karst of the region, geological environment of the cave, speleomorphogenesis, morphological structure of the cave network, hydrology, breakdown processes and sinkhole development, cave sediments, cave microclimate, life in the cave, cave genesis and age, scientific and practical importance of the cave.
In Russian, with extended abstract and captions in English and Polish.
This book provides an overview of the principal environments, main processes and manifestations of hypogenic speleogenesis, and refines the relevant conceptual framework. It consolidates the notion of hypogenic karst as one of the two major types of karst systems (the other being epigenetic karst). Karst is viewed in the context of regional groundwater flow systems, which provide the systematic transport and distribution mechanisms needed to produce and maintain the disequilibrium conditions necessary for speleogenesis. Hypogenic and epigenic karst systems are regularly associated with different types, patterns and segments of flow systems, characterized by distinct hydrokinetic, chemical and thermal conditions. Epigenic karst systems are predominantly local systems, and/or parts of recharge segments of intermediate and regional systems. Hypogenic karst is associated with discharge regimes of regional or intermediate flow systems.
Various styles of hypogenic caves that were previously considered unrelated, specific either to certain lithologies or chemical mechanisms are shown to share common hydrogeologic genetic backgrounds. In contrast to the currently predominant view of hypogenic speleogenesis as a specific geochemical phenomenon, the broad hydrogeological approach is adopted in this book. Hypogenic speleogenesis is defined with reference to the source of fluid recharge to the cave-forming zone, and type of flow system. It is shown that confined settings are the principal hydrogeologic environment for hypogenic speleogenesis. However, there is a general evolutionary trend for hypogenic karst systems to lose their confinement due to uplift and denudation and due to their own expansion. Confined hypogenic caves may experience substantial modification or be partially or largely overprinted under subsequent unconfined (vadose) stages, either by epigenic processes or continuing unconfined hypogenic processes, especially when H2S dissolution mechanisms are involved.
Hypogenic confined systems evolve to facilitate cross-formational hydraulic communication between common aquifers, or between laterally transmissive beds in heterogeneous soluble formations, across cave-forming zones. The latter originally represented low-permeability, separating units supporting vertical rather than lateral flow. Layered heterogeneity in permeability and breaches in connectivity between different fracture porosity structures across soluble formations are important controls over the spatial organization of evolving ascending hypogenic cave systems. Transverse hydraulic communication across lithological and porosity system boundaries, which commonly coincide with major contrasts in water chemistry, gas composition and temperature, is potent enough to drive various disequilibrium and reaction dissolution mechanisms. Hypogenic speleogenesis may operate in both carbonates and evaporites, but also in some clastic rocks with soluble cement. Its main characteristic is the lack of genetic relationship with groundwater recharge from the overlying or immediately adjacent surface. It may not be manifest at the surface at all, receiving some expression only during later stages of uplift and denudation. In many instances, hypogenic speleogenesis is largely climate- independent.
There is a specific hydrogeologic mechanism inherent in hypogenic transverse speleogenesis (restricted input/output) that suppresses the positive flow-dissolution feedback and speleogenetic competition in an initial flowpath network. This accounts for the development of more pervasive channeling and maze patterns in confined settings where appropriate structural prerequisites exist. As forced-flow regimes in confined settings are commonly sluggish, buoyancy dissolution driven by either solute or thermal density differences is important in hypogenic speleogenesis.
In identifying hypogenic caves, the primary criteria are morphological (patterns and meso-morphology) and hydrogeological (hydrostratigraphic position and recharge/flow pattern viewed from the perspective of the evolution of a regional groundwater flow system). Elementary patterns typical for hypogenic caves are network mazes, spongework mazes, irregular chambers and isolated passages or crude passage clusters. They often combine to form composite patterns and complex 3- D structures. Hypogenic caves are identified in various geological and tectonic settings, and in various lithologies. Despite these variations, resultant caves demonstrate a remarkable similarity in cave patterns and meso-morphology, which strongly suggests that the hydrogeologic settings were broadly identical in their formation. Presence of the characteristic morphologic suites of rising flow with buoyancy components is one of the most decisive criteria for identifying hypogenic speleogenesis, which is much more widespread than was previously presumed. Hypogenic caves include many of the largest, by integrated length and by volume, documented caves in the world.
The refined conceptual framework of hypogenic speleogenesis has broad implications in applied fields and promises to create a greater demand for karst and cave expertise by practicing hydrogeology, geological engineering, economic geology, and mineral resource industries. Any generalization of the hydrogeology of karst aquifers, as well as approaches to practical issues and resource prospecting in karst regions, should take into account the different nature and characteristics of hypogenic and epigenic karst systems. Hydraulic properties of karst aquifers, evolved in response to hypogenic speleogenesis, are characteristically different from epigenic karst aquifers. In hypogenic systems, cave porosity is roughly an order of magnitude greater, and areal coverage of caves is five times greater than in epigenic karst systems. Hypogenic speleogenesis commonly results in more isotropic conduit permeability pervasively distributed within highly karstified areas measuring up to several square kilometers. Although being vertically and laterally integrated throughout conduit clusters, hypogenic systems, however, do not transmit flow laterally for considerable distances. Hypogenic speleogenesis can affect regional subsurface fluid flow by greatly enhancing initially available cross- formational permeability structures, providing higher local vertical hydraulic connections between lateral stratiform pathways for groundwater flow, and creating discharge segments of flow systems, the areas of low- fluid potential recognizable at the regional scale. Discharge of artesian karst springs, which are modern outlets of hypogenic karst systems, is often very large and steady, being moderated by the high karstic storage developed in the karstified zones and by the hydraulic capacity of an entire artesian system. Hypogenic speleogenesis plays an important role in conditioning related processes such as hydrothermal mineralization, diagenesis, and hydrocarbon transport and entrapment.
An appreciation of the wide occurrence of hypogenic karst systems, marked specifics in their origin, development and characteristics, and their scientific and practical importance, calls for revisiting and expanding the current predominantly epigenic paradigm of karst and cave science.
![]() |
![]() |