Cryogenic Origin Research Articles

NON-KARSTIC SPELEOGENESIS IN SANDSTONE ROCKS OF UKRAINIAN CARPATHIANS

Due to the limited distribution of karst rocks and, accordingly, the small number of karst caves in the Ukrainian Carpathians, the caves of non-karst (pseudokarst, clastokarst) genesis attract considerable attention from cave researchers. The latter most often develop in massive and coarse-grained sandstone strata, usually found as part of flysch strata. The caves of non-karstic genesis are widely spread in the Cretaceous and Paleogene sandstone formations of the Ukrainian Carpathians. Most of them are developed in the massive sandstone of the Yamna Formation of the Palaeocene. The primary information about all caves on the territory of Ukraine is collected by the Commission for Accounting and Documentation of Caves of the Ukrainian Speleological Association (UkrSA), and by local caving clubs and individual researchers. Currently, the number of discovered caves in the sandstone of the Ukrainian Carpathians exceeds the number of mapped caves, not to mention their detailed description. The minimal information about each cavity includes the name, entrance coordinates, total length, and depth (amplitude) resulting from the cave survey. The additional description could contain knowledge about the history of the cave discovery, origin, geological settings, microclimate, sediments, inhabitants, paleontological and archaeological remains, etc. At present, many caves have been discovered in a few microregions: Kliuch Ridge, near Skole; the tract Drybka, between Yaremche and Yamna; on Sokilsky Ridge, and its south-eastern orographic continuation at tracts Protiate Kaminnia and Lekeche; Polonyna Runna; Lubnia Village; and Chorna Gora Ridge. Few yet not mapped cavities are known in Bubnyshche, Synytsia Mt., and some other sites. Most caves belong to three genetic types: tectonic, gravitational, and selective corrosion. The largest among tectonic caves is Tectonic (Dovbush) cave near Yamna Village, which is 388 m long. The longest selective-corrosion cave is 92 m long. Some caves with fissure-like morphology could also be of cryogenic origin. We suggest that the caves with the fissure-like morphology are the forms of paleoseismic dislocations. Keywords: sandstone; pseudokarst; speleogenesis; selective corrosion; Ukrainian Carpathians.

Cryogenic ridges: a new speleothem type

Cryogenic cave carbonates have been described from several formerly or presently glaciated karst caves. In most of these occurrences, they precipitated as loose grains or aggregates with various morphologies and sizes. Here, we report on a new speleothem type (cryogenic ridges) identified in Sohodoalele Mici Cave (SW Romania) within a large chamber near the entrance shaft. This study was motivated by the presence of a network of calcite ridges over the stalactites’ surface and by the observation that during winter, these speleothems are covered by a thin ice layer. The higher δ18O (−3.5 to –1‰) and δ13C (0 to 7‰) values found in the calcite ridges relative to δ18O (–7.5 to –4‰) and δ13C (–9 to –2‰) values of calcite from the inner stalactite indicate that the ridges are of cryogenic origin and formed during relatively rapid carbonate precipitation associated with evaporative cooling and freezing of the water. Four U-series ages suggest that the stalactites with ridges formed during cold winters of the Holocene, when cave air temperatures dropped below freezing.

Composite sand-ice wedge pseudomorphs suggestive of a frosty Ediacaran–Cambrian transition

The Ediacaran–Cambrian transition (approx. 580–520 million years ago), one of the most critical intervals in Earth's history, witnessed physical environment change and climate fluctuations coupled with extraordinary radiations of metazoan life. Up to now, there are insufficient data to evaluate the true nature of the Ediacaran–Cambrian transition climate. This research reports the newly discovered wedge structures on the Luoquan glacial diamictites in western Henan, North China Craton, to discuss and try to prove the nature of the Ediacaran–Cambrian transition climate fluctuation. The results show that the Luoquan wedges show downward V-shaped pinching in two dimensions, with heights of 20–400 cm and widths of 3–25 cm. A cryogenic origin of composite sand-ice wedge pseudomorphs is the most likely interpretation based on observations of their morphological, textural, and sedimentological characteristics. The observed evidence is ambiguous but could indicate an extremely cold climate resulting in periglacial environments during the Ediacaran–Cambrian transition. These findings can contribute to a better understanding of extreme fluctuations in the global climate that probably affected ocean chemistry and biological evolution during the Ediacaran–Cambrian transition.

Cryogenic origin of fractionation between perchlorate and chloride under modern martian climate

The high perchlorate (ClO4−) to chloride (Cl−) ratios observed at the Phoenix landing site, northern polar region of Mars, have been puzzling since detection. However, a lack of understanding of perchlorate-chloride-water systems under cryogenic conditions makes it difficult to assess ClO4−/Cl− ratios during deliquescence-related processes. Here we quantitatively evaluate ClO4−/Cl− fractionation in deliquescence-induced brines of magnesium- and calcium-perchlorate-chloride salt mixtures under subzero conditions, by measuring solubility data and constructing temperature-dependent thermodynamic models. We find that under specific relative humidity (RH) and temperature (T) conditions, deliquescence of perchlorate-chloride mixtures may form brines with fractionated ClO4−/Cl− signatures. Appropriate RH-T, water-limited conditions, and aeolian processes are required to produce and preserve the elevated ClO4−/Cl− signatures in soils. Under the present climate, the north polar region can support ClO4−/Cl− fractionation and potentially enrich perchlorate for longer periods on global Mars. This highlights the uniqueness of Mars’ arctic environment and its implications for modern habitability.

Interpretation of the anomalous groundwater chemistry and 234U/238U activity ratio disequilibrium in the northern part of the baltic region

The anomalous isotope-hydrogeochemistry phenomena in the groundwater of Estonian Cambrian-Vendian (Ediacaran) and Ordovician-Cambrian aquifer systems were formed in the Late-Middle Pleistocene. In the periglacial environment, in northern and northwestern Estonia, these aquifer systems with fracture porose crystalline basement are connected to hydraulically joint unit characterized by high radioactivity groundwater. A significant alteration of groundwater occurred by series of isotope and chemistry facies fractionation. In this study, uranium isotopes activity ratio (234U/238U), 4He content, isotope-hydrogeochemistry and adjusted 14C ages are coupled for a new prospect of the estimation of northern Baltic Basin groundwater evolution. Analyzing radiocarbon and 4He groundwater residence time results and uranium isotope activity ratio distribution suggests a prolonged periglacial environment in which groundwater evolved. Stable isotope ratios of δ18O and δ2H correlation and hydrochemical composition changes support the cryogenic origin of groundwater. Pleistocene glaciations cyclically affect groundwater in multiple ways: permafrost isotope-geochemistry partitioning; periodically changing reversed flow directions of recharge and discharge areas; oscillations of the sea, river system, and periglacial lakes level, surface and sub-permafrost water mixing via taliks and fractured basement rocks. These processes lead to forming the sequence of isotope-hydrogeochemistry types and specific zoning; in general, two separate groundwater fractions – brackish in the lower part and freshened above. An extensive groundwater exploitation on the northern coast sites influenced a sharp dysfunction in the groundwater body, destabilizing the natural equilibrium state formed in the Holocene and Pleistocene.

Seismic Monitoring of Permafrost in Svalbard, Arctic Norway

AbstractWe analyze data from passive and active seismic experiments conducted in the Adventdalen valley of Svalbard in the Norwegian Arctic. Our objective is to characterize the ambient wavefield of the region and to investigate permafrost dynamics through estimates of seismic velocity variations. We are motivated by a need for early geophysical detection of potentially hazardous changes to permafrost stability. We draw upon several data sources to constrain various aspects of seismic wave propagation in Adventdalen. We use f-k analysis of five years of continuous data from the Spitsbergen seismic array (SPITS) to demonstrate that ambient seismic noise on Svalbard consists of continuously present body waves and intermittent surface waves appearing at regular intervals. A change in wavefield direction accompanies the sudden onset of surface waves when the average temperature rises above the freezing point, suggesting a cryogenic origin. This hypothesis is supported further by our analysis of records from a temporary broadband network, which indicates that the background wavefield is dominated by icequakes. Synthetic Green’s functions calculated from a 3D velocity model match well with empirical Green’s functions constructed from the recorded ambient seismic noise. We use a shallow shear-wave velocity model, obtained from active seismic measurements, to estimate the maximum depth of Rayleigh wave sensitivity to changes in shear velocity to be in the 50–100 m range. We extract seasonal variations in seismic velocities from ambient noise cross-correlation functions computed over three years of SPITS data. We attribute relative velocity variations to changes in the ice content of the shallow (2–4 m depth) permafrost, which is sensitive to seasonal temperature changes. A linear decreasing trend in seismic velocity is observed over the years, most likely due to permafrost warming.

Cryogenic processes in soils of chalky landscapes in steppe zone south of the Orenburg region

Specific microrelief marked by white chalky spots at the soil surface was studied in Volga-Ural region. The microrelief was described and soil features were studied in a soil trench across the microrelief including morphology and further micromorphology in the thin sections with the aim to better understand the genesis and functioning of chalky polygons, and to testify the hypothesis of their cryogenic origin. Wide range of cryogenic features was found both at macro- and microscale. Some are expected to be relict, while the other features are supported or formed by modern cryogenic processes. The further investigation of the temperature regime is planned to investigate the spatial diversity and role of winter freezing in the modern squeezing of wet powdery chalky material to the soil surface.

Характеристика вторичных отложений в пещере Старателей (Свердловская область)

The paper reports, for the first time, on cryogenic minerals and flowstones in the Starateley cave on the River Sosʼva (the Northern Urals). The cave was found and explored in 2011; presently it is one of the largest, in terms of its volume, underground caverns in the Sverdlovsk Region. Upon our visit in 2016 in addition to «common»speleothems, such as cryogenic flour and flowstone, we have found peculiar aggregates of yellowish calcite as well as cave pearls. The depleted O and enriched C isotope signatures indicate cryogenic origin of this calcite and its formation from slowly freezing solution. Dating cryogenic calcite with 230 Th/ 234 U method allow to constraint the time of climate warming-related thawing of permafrost on the eastern slope of the Northern Ural Mountains to 85.4 ± 0.5 ka BP. The age of cave pearls is Holocene (7.4 ± 2.1 ka BP). Stalagmite sample has not been dated due to low U contents and inferred «open system» behavior of U and Th isotopes.

Cryogenic carbonates and cryogenic speleothem damage in the Za Hájovnou Cave (Javoříčko Karst, Czech Republic)

A new locality of coarse-grained cryogenic cave carbonates has been found in the Za Hajovnou Cave in Javořicko Karst in Central Moravia, Czech Republic. Crystals and crystal aggregates, usually up to 15 mm in size, form typical loose accumulations on the surface of large fallen limestone blocks and clays covering the bottoms of several cave chambers distant from the cave entrance. The cryogenic origin of the carbonates is supported by their mode of occurrence, specific crystal and aggregate morphology, and C and O stable isotope data. U-series dating of one sample of cryogenic carbonate (age 29.5 ±0.1 ka) indicated that a period of karst water freezing occurred in marine isotope stage (MIS) 3, within the Weichselian. The cave also hosts numerous examples of speleothem damage. As shown in this paper, some of these are clearly connected with freezing conditions and cave ice action.

INVESTIGATION OF THE PROPERTIES OF MARMALADE WITH PLANT CRYOADDITIVES DURING STORAGE

This article presents the results of studies of the properties of marmalade with natural plant cryoadditives during storage for 3 months (90 days). To improve the organoleptic characteristics and antioxidant properties of marmalade, plant additives of cryogenic origin were used, namely cryopastes from quince, apple, carrot, pumpkin, grapes, and cryopowders from rose hips, sea buckthorn, and grapes. It is shown that the use of plant cryoadditives makes it possible to increase the biological value and antioxidant properties of new types of marmalade. For new types of marmalade with cryoadditives, during its shelf life, these properties have not been studied earlier. However, it should be noted that such studies are necessary and relevant for solving the problem of preserving the quality indicators and antioxidant capacity of marmalade with cryoadditives. New kinds of marmalade have high organoleptic characteristics during the whole storage period. It is shown that the storage conditions of marmalade, according to current regulatory documentation, are suitable for new marmalade products, since the physico-chemical and microbiological indicators vary, but remain within acceptable limits. Thus, the moisture content decreases to almost 31%, the acidity rises by 12–16%, compared to freshly prepared samples. The content of reducing substances increases by 30–64%. It is determined that the value of the antioxidant capacity of all the samples developed is much higher – almost 2.3–8 times than the same figure for the control sample. After the storage period, the antioxidant capacity is reduced by 15–35%, but this data also significantly exceeds the antioxidant capacity of the control sample. Storage of marmalade with cryopastes and cryopowders for 90 days is possible, since all the basic physico-chemical, microbiological, and organoleptic indicators at the end of shelf life meet the requirements. Indicators of antioxidant capacity for them also remain at a fairly high level. New technologies of jelly-fruit marmalade with plant cryoadditives have been introduced at 4 enterprises. 2 utility model patents have been received, and regulatory documents have been developed and approved for the manufacture of new jelly products.

Geochemical characteristics of the infilling of ground wedges at Puerto Deseado (Santa Cruz, Argentina): palaeoenvironmental and chronological implications

Ground wedge structures of cryogenic origin are common in the Quaternary sediments along the coast of the Patagonia, and their formation is related to climatic cold events experienced by this area in the Late Quaternary. The infilling sediments of two wedges generations were analyzed in the area of Puerto Deseado. Bulk chemistry (major elements), X-ray diffraction (XRD), morphoscopic observations with Scanning Electronic Microscope (SEM) and chemical analyses of volcanic glass shards were undertaken to provide indications about infilling sediment provenience, along with chronological constraint for wedge formation. Bulk chemistry and XRD patterns indicate a significant SiO2-enriched composition of the sediment infilling compared to the most of the loess deposits of the North Argentina and the present day dust originated in Patagonia. This was interpreted as due to the nature of the bedrock present over the Deseado Massif. SEM morphoscopic characteristics of glass shards evidence typical aeolian reworking features, with impact structures and indented edges of the volcanic fragments. Chemical analyses of the glass shards indicate that they were probably generated by the H0 eruption (17,300-17,400 cal yr BP) of the Hudson volcano. Volcanological data indicate that H0 eruption dispersed toward NE, but volcanic glasses were available for reworking due to a WNW component in the western wind direction. Over the Deseado Massif structural high the glass shards mixed with sediments enriched in SiO2, and were eventually deflated further to SE reaching the present coastal area and infilling the frost cracks. The age of the glass shards (17,300-17,400 cal yr BP) and that of the sandy layer affected by cryogenic structures (14,670±750 yr BP) well constrain to the Late Glacial both wedge generations.

Cryogenic Deformation Structures in Late Cenozoic Unconsolidated Sediments of the Tunka Depression in the Baikal Rift Zone

The Late Cenozoic alluvial deposits in the Tunka depression of the Baikal Rift Zone, Russia, contain wedge-shaped structures and involutions that provide valuable palaeogeographic information about the southern part of eastern Siberia. The structure of the unconsolidated host deposits, the shape and size of the deformation structures (wedge shaped, wave like or drop like) and the physical-mechanical properties of the sediments (particle size, density, porosity, water content and colour) point to a cryogenic origin of the deformation structures, as ice wedge pseudomorphs and cryoturbations, rather than an origin associated with seismic activity or sedimentation. The oldest pseudomorphs and cryoturbations developed during climate-warming periods of the subboreal climatic phase (3600–2600 years ago). Copyright © 2014 John Wiley & Sons, Ltd.

Noble gas concentrations in fluid inclusions as tracer for the origin of coarse-crystalline cryogenic cave carbonates

The chemically inert behaviour of noble gases, their well-known solubility in water and the long-term constancy of atmospheric noble gas mixing ratios make them a unique tool for paleoclimate studies of groundwater. This concept has recently been extended to fluid inclusions in speleothems. Here we use noble gas concentrations of fluid inclusions contained in calcite crystals to constrain the formation history of coarse crystalline cryogenic cave calcites from Heilenbecker Cave (Germany).Cryogenic cave carbonates form under conditions related to the freezing of cave pools and are a new archive for paleo-permafrost timing and extent. The cryogenic origin of these carbonates is typically deduced from their crystal habit and the carbon and oxygen isotope ratios, but this can be ambiguous in some cases. A geochemical method that provides clear-cut proof of the cryogenic origin of individual crystals has been lacking so far.We examined the formation process of cryogenic cave calcites using water and noble gases extracted from inclusions in these crystals. Based on their δ13C and δ18O values, these calcite crystals could have also formed as ‘normal’, i.e. non-cryogenic, speleothems. Noble gas concentrations derived from fluid inclusions in these cryogenic calcites, however, deviate significantly from commonly observed concentrations in atmospheric air, surface water, groundwater, and stalagmites. These concentrations cannot be explained simply by a solubility component nor by the addition of various amounts of excess-air to a solubility component. The data, however, are consistent with the scenario of a slowly freezing water body lacking exchange with the cave atmosphere. The gradual freezing process leads to a partitioning of the noble gases between ice and remaining water and thereby to a pronounced over-abundance of heavy noble gases in the liquid phase recorded in the fluid inclusions of the cryogenic calcite crystals.

Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates

Abstract. Coarse crystalline cryogenic cave carbonates (CCCcoarse) dated to the last glacial period are common in central European caves and provide convincing evidence of palaeo-permafrost during this time. Little is known, however, about the exact nature of the environment in which CCCcoarse formed as no modern analogue setting is known. Here, we report the first findings of sub-recent, albeit inactive, CCCcoarse from a cave of the Western Alps which is located in the present-day permafrost zone. The globular shape and the presence of ubiquitous euhedral crystal terminations are comparable to previously reported aggregates from the last glacial period and strongly suggest that these aggregates formed subaqueously in pools lacking agitation. Furthermore, stable isotope values of mm-sized spheroids point to calcite precipitation in a closed system with respect to CO2, strongly supporting the hypothesis of a cryogenic origin associated with the freezing of water ponds. U-series analyses revealed three clusters of late Holocene calcite precipitation intervals between 2129 and 751 a b2k. These ages correlate with known periods of elevated summer temperatures, suggesting that warming and thawing of the frozen catchment above the cave allowed water infiltration into the karst system. The growth of CCCcoarse resulted from the re-freezing of this water in the still cold karst cavities.

Cryogenic origin for brine in the subsurface of southern McMurdo Sound, Antarctica

Sampling of interstitial fluids during deep coring in southern McMurdo Sound, Antarctica, revealed the presence of seawater-sourced, hypersaline brine at depths >200 m below the seafloor. Na-Cl-Br and SO 4 -Cl-Br relationships are consistent with a concentration mechanism that involves the removal of pure H 2 O as ice and precipitation of mirabilite (Na 2 SO 4 ·10H 2 O) during progressive freezing of seawater. The brine is in Neogene subglacial, glacimarine, and marine facies that record advance and retreat of glaciers through the Ross Sea embayment. In this environment, sea ice formation in semi-isolated marine basins that occupied flexural troughs along ice sheet margins produced dense brines that sank and infiltrated the permeable subglacial sediment. Repeated cycles of glacial advance and retreat provided multiple opportunities for batches of seawater to be transformed into brine that now is in the subsurface of southern McMurdo Sound. Results demonstrate the feasibility of brine formation via seawater freezing and attest to the potential of a cryogenic origin for subsurface brines in high-latitude regions of the Northern Hemisphere, as proposed by some workers.

Processes responsible for the development of a pit and mound microrelief

Hummocky ground is a conspicuous feature of some cultivated pastures in the mountain forests of the Alps. In the German scientific literature, this pit and mound microrelief is termed “Buckelwiese” (literally: “hummocky meadow”) and is commonly interpreted as a fossil, Late Glacial relief of cryogenic origin. This paper suggests an alternative hypothesis, namely that relief formation was initiated by the uprooting of trees during storms. In the rootstock-pits, karst processes gradually amplified the initial relief. This alternative hypothesis is tested in a Buckelwiesen area of the Northern Limestone Alps, where pit-to-mound vertical relief amounts to 52 cm and mounds are 250–510 cm long and 170–270 cm wide, and the density of pits and mounds is 400 ha −1. Field investigations included a ground survey using a tacheometer and the excavation of a trench to check the internal structure of one pit-mound couple. The trench was subsequently used to estimate solution rates in the subsurface material of pits and mounds. Based on the results of the field measurements and two radiocarbon dates from the test site, the paper concludes that in the study area a treethrow event occurred between 1120 and 1280 AD. Subsequently, the pits created by the uprooted trees were deepened by limestone solution at a rate of 77.2 mm/1000 years. The reconstructed formation history of the microrelief of the study area is consistent with a Holocene origin, with rates of limestone dissolution as measured in the field and with the morphometry of the features themselves.

Periglacial evidence from the western Cape Mountains, South Africa: A progress report

AbstractExtensive Pleistocene debris deposits occur in the Western Cape Mountains, South Africa. Although a cryogenic origin for the clasts is generally accepted, there is still discussion about the conditions under which debris transport and deposition took place. In the Waaihoek Mountains solifluction features occur at 1800m a.s.l. Present‐day periglacial activity results from surficial soil frost action and snowfalls in the cold season. To assess the significance of freeze‐thaw action on soil movement rates, continuous and periodic measurements are being made of climatic parameters and soil movement at several experimental sites, including a snowpatch site, at 1850m a.s.l. in the Waaihoek Mountains.

Water escape fissures resembling ice‐wedge casts in Late Quaternay subaquesous outwash near St. Lazare Québec, Canada

Post‐depositional structures in late Quaternary subaqueous outwash near St. Lazare, Québec resemble icewedge casts but are interpreted as water escape fissures. Cryogenic origin is discounted because, in contrast with ice‐wedge casts, the fissures have a higher depth to width ratio, do not form an intersecting network, and do not exhibit adjacent upward turning of strata. In addition, their truncation by the sub‐littoral unconformitydemonstrates formation before regression of the post‐glacial Champlain Sea, under conditions in which ground ice development was highly unlikely. The fissures probably formed in response to elevated pore pressures caused by melting of remnant glacier ice or by liquefaction of deeper units. Excess pore water pressure initiated upward flow of dilute sediment‐water mixtures that became concentrated in planar zones (fissures) along which they entrained and removed sediment. Slumping of the fissure walls followed, either during or after water escape. Minor faulting over cavities created by melting ice or water escape along fractures in underlying strata may have controlled the morphology of the fissures.

Criteria for identifying cryogenic origin of secondary dispersion halos of ore deposits

Criteria for identifying cryogenic origin of secondary dispersion halos of ore deposits