Search

Abstract The geological model of large hydrothermal salt accumulations linked to "Wilson cycles" as reviewed by Hovland and Coworkers, un-adequately addressed: (1) the lack of well exposed submarine volcanogenic hydrothermal feeder zone, (2) the sequential precipitation of different hydrothermal evaporite minerals and (3) the absence of hydrothermal alteration mineralogy around the major evaporites. These aforementioned points are the main classical features to be linked to the hydrothermal model of evaporites. Experimentally, heating seawater during submarine volcanism firstly results in precipitation of anhydrite followed by halite, other evaporite minerals, serpentine, brucite, talc, metallic sulfides-oxides and related hydrothermal alterations. In this regard, Mg/Ca – Cl, Mg/Ca – SO 4 , Mg/Ca – Na/Cl and Mg/Ca - TDS biplots show that hydrothermal brines of riftogenic and subduction zone settings plot in a separate field than the subduction-related Andean Salars as well as seawater. This indicates that the hydrothermal serpentinization of basaltic oceanic crust and mantle peridotites removes magnesium from seawater and incorporates the Mg into serpentine, brucite and other hydrous Mg-silicates rather than the hydrothermal brines. Finally, our comment arose from a recent global classification of the most distinguished marine, non-marine and exhalative hydrothermal evaporites. Highlights • Major types of evaporites are of solar origin. • Minor hydrothermal evaporites are linked to submarine hydrothermal fluids. • Hydrothermal evaporites show volcanogenic feeder zone and alteration mineralogy. • Mg/Ca-Cl and Mg/Ca-Na/Cl diagrams separate hydrothermal evaporites from solar ones. • A new global map highlights the marine, non-marine and hydrothermal evaporites. [ABSTRACT FROM AUTHOR]

Tropical coastal karst areas represent dynamic, fragile, and biodiverse environments. Central America's karst regions have been scarcely studied, with most of the research focused on the northern part of the region and on several larger cave systems. The coastal carbonate zones of the Central American region represent a unique karstic landscape, which, so far, has been insufficiently studied. Therefore, in this paper, we aim to describe the (i) landscape geomorphology and (ii) chemical conditions that define Ciénega de El Mangle in Panama as a distinctive karstic site. Carried geomorphological mapping and the characterization of karstic features have resulted in the identification of the different karstic forms and processes that are present within this unique karstic area. Considering that the chosen karstic study area is located in a marine–coastal fringe on the periphery of a lagoon, it is affected by a combination of several factors and processes, including seawater intrusion (through sinkholes), the formation of conchiferous limestone (CaCO3), and NaCl precipitation related to efflorescence. Due to the seasonally humid tropical climate, the chemical weathering processes are intense, thus forming alkaline soils that are hindering the development of mangrove vegetation. The geomorphology of the area results from intense evaporation combined with an influx of brackish groundwater, due to which a landscape has evolved in the marine–coastal strips, of seasonal tropical climates, that exhibit saline beaches, known as a littoral shott. In total, 24 karstic microdolines have evolved within the shott, of which six represent domical geoforms formed by gradual evaporitic precipitation, while seven other geoforms represent active karstic sinkholes filled with brackish water. These results are key for understanding the past and present climate interactions and conditions that have led to the formation of tropical karst environments. [ABSTRACT FROM AUTHOR]

The Upper Permian Zechstein Supergroup has the potential to play an important role in the UK's future energy production and energy transition. However the Supergroup is comparatively poorly understood in the UK, particularly the link between the onshore and offshore geology. In this paper we re‐evaluate available data in order to present a consistent regional interpretation of the Z1 to Z3 Zechstein Supergroup cycles. This review is based on an interpretation and re‐evaluation of 620 offshore wells located in the UK portion of the SW Southern North Sea and 83 onshore wells located in Yorkshire and Lincolnshire (eastern England). The Zechstein Supergroup was interpreted in each well, and the data was used to compile seven SW‐NE oriented correlation panels which show the development of the Supergroup in the study region. Five isopach maps for key formations in the Zechstein Supergroup were created, together with depositional environment maps for each of the main Zechstein carbonate formations. In combination, these regional‐scale maps and diagrams have resulted in a consistent interpretation of the Zechstein Supergroup over an area which extends from the onshore outcrop in the west to the UKCS boundary in the Southern North Sea in the east. [ABSTRACT FROM AUTHOR]

Sinkholes are a severe problem in urban areas located in karstic regions, especially where evaporitic rocks such as gypsum exist. Identification and proposal of mitigation measures are needed to reduce this geo-hazard effect on buildings and social urban living. This paper presents a case study of the town of Alcalá de Ebro (Spain), which is located in the highest sinkhole risk region of Europe. The identification and mitigation of a series of sinkholes that appeared are analyzed. The former involves a geological investigation, including boreholes, field tests and geophysics. The latter is addressed by the use of geogrids, mortar injections and polyurethane injections. A complementary finite element analysis is carried out to set the ground behavior associated with the sinking process and assess its future evolution. The Ebro River appears to be the main cause of sinkholes, and results show that ground treatments applied were successful in their purpose, as there are no apparent deformations indicating that the subsidence or sinking process is still active in the area. The use of different techniques depending on the size of the sinkhole, the objectives pursued and the element affected is discussed. [ABSTRACT FROM AUTHOR]

Atmospheric CO2 concentrations can reach high levels inside natural caves, representing a hazardous condition for both humans frequenting the underground environment and its safeguard due to the corrosion of speleothems induced by the acidification of atmospheric moisture. These issues are particularly critical for the eco-sustainable management of caves protected as nature reserves and undergoing touristic exploitation. In this paper we present the results of the C6 project, which was activated in 1999 for the monitoring of air quality inside three caves protected as nature reserves in Sicily (Italy). Near-real-time and spot measurements of air temperature and CO2 concentration have been carried out since the year 2000, giving the opportunity of evaluating the gas hazard for visitors and its potential impact on the protected underground environments, as well as the influence of meteorological and hydrological conditions in driving carbon dioxide accumulations. The analysis of data acquired in the hypogeal atmosphere, and their comparison with analogous epigeal measures, indicates that carbon dioxide accumulation is controlled by a complex interaction among cave topography, meteorological dynamics, gaseous exchanges between groundwaters and the atmosphere, and human fruition. This last factor, under particular conditions, can surprisingly diminishing underground CO2 concentrations. [ABSTRACT FROM AUTHOR]

The identification of potassium (K) and magnesium (Mg) salts prior to the well drilling is a key factor to avoid washouts, closing pipes, fluid loss damage, and borehole collapse. The Bayesian classification combines the outcomes from statistical rock physics and seismic inversion, providing the spatial occurrence of the most-probable salt types. It serves as a facies identifier of Mg–K-rich salts (bittern salts) before drilling. Nevertheless, the most-probable classification is limited to the seismic resolution which may underestimate seismically thin-layer thicknesses. Along with the most-probable facies, the Bayesian classification renders the facies probability volume. We demonstrate that the facies probability and facies-specific total thickness highly correlate to each other even under the threshold of seismic resolution. Thus, we employ the bittern-salts probability volume to predict thin-bed bittern-salts thickness in undrilled locations. To capture the variability of the seismic estimation, we resort to Monte Carlo-assisted simulations of wells that emulate the layering patterns of a site-specific deposition environment. These simulations are crucial to assist the estimation of the joint probability density function between the facies volume and the total thickness. Therefore, given the facies probability, the joint probability density function enables us to derive the conditional expectation and percentiles of thin-bed thicknesses. Furthermore, this paper proposes a method to quantify the negative influence of seismic noise in the estimation of thin-bed thicknesses. The blind well confirms the consistency of this technique to unfold the uncertainty in the seismic predictability of thin layers. We argue that this procedure is extendable to other facies. [ABSTRACT FROM AUTHOR]

Structural decoupling in the Zagros fold‐and‐thrust belt, SW Iran, is controlled by the presence of intermediate detachment horizons within the Phanerozoic stratigraphic column such as intervals rich in evaporites. The effectiveness of the detachment horizons varies across the Zagros, and controls the style of folding and therefore the formation of structural traps. In this paper, field mapping, seismic interpretation and well data is used to investigate the complex structural style at six large‐scale anticlines located on either side of the surface trace of the NW‐SE trending Zagros Frontal Fault system in the South Dezful Embayment (Central Zagros). At some of these anticlines, lower – middle Miocene evaporites in the Gachsaran Formation decouple the folded overlying succession from the competent, underlying interval which includes the Asmari Formation reservoir. Anticlines to the northeast of the surface exposure of the fault have undergone four times more shortening than anticlines to the southwest. This localized shortening compared to regional values has resulted in some cases in complex asymmetric folding, and in severe structural decoupling above and below the Gachsaran Formation. However, other anticlines to the NE of the fault which underwent a similar amount of shortening, but in which the thickness of the Gachsaran Formation is reduced and the salt content is lower, show a harmonic style of folding above and below the formation. Thus, the efficiency of the Gachsaran detachment varies throughout the study area and appears to be controlled mainly by the total thickness of the formation, the net thickness of salt‐rich intervals within it, and the amount of structural shortening across the Zagros Frontal Fault system. These observations could be relevant to similar structural domains both in the Zagros and in other fold‐and‐thrust belts where intermediate detachment horizons and regional‐scale faults have together controlled the configuration of folds and structural traps. [ABSTRACT FROM AUTHOR]

The territory of Albania presents wide outcrops of soluble rocks, with typical karst landforms and the presence of remarkable carbonate aquifers. Many karst areas are located near the coasts, which results in a variety of environmental problems, mostly related to marine intrusion. This paper focuses on the brackish springs of Albania, which exhibit temperatures approximately equal to the yearly air temperature at their location. Total dissolved solids of the springs are higher than 1000 mg/L, their waters are not drinkable, and they are rarely used for other purposes. The groundwater of the alluvial aquifers of Albania, particularly those of Pre-Adriatic Lowland, are often brackish too, but these will not be addressed here. Brackish springs of Albania are mainly of karst origin and can be classified into two groups: springs in evaporitic rock, mainly gypsum, and springs in carbonate rock. The hydro-chemical facies of the first group are usually Ca-SO4, locally with increased concentrations of Na-Cl, whereas springs belonging to the second group usually exhibit Na-Cl facies. The largest brackish springs of Albania are described in detail, including their hydro-chemical correlations. [ABSTRACT FROM AUTHOR]

The internal structure and architecture of evaporite sequences is often overlooked, with attention frequently concentrating on the external geometries that salt bodies form. The availability of extensive 3D seismic data affords the opportunity to interpret the internal structures within these evaporite sequences and comprehensively characterise the different structural facies over large areas. This paper concentrates on the Zechstein Supergroup evaporite deposits within the Southern North Sea of the United Kingdom's Continental Shelf. This analysis of the internal structural complexity and stratigraphic heterogeneity utilises 26,000 km2 of 3D seismic data together with over 96 wells from the Southern North Sea. Characterisation of the different structural facies present was undertaken alongside mapping their spatial distribution to understand the relationship they have with one another and the structural evolution that may have been taken. This work has (1) characterised and mapped six different internal structural facies present within the Zechstein with increasing levels of deformation; (2) shown the internal lithological heterogeneity is indicative of variations in the vertical strength profile of layered evaporite sequences; (3) discontinuous high‐amplitude reflections within the Zechstein are as a result of the geometries being too steeply dipping for the seismic data to image; and (4) the ability to possibly predict the internal heterogeneity of areas of poorly imaged salt, such as within large diapiric salt structures, from surrounding structural facies. These findings suggest that there is significant internal complexity even within areas of the basin with minor mobilisation to the external salt geometry. [ABSTRACT FROM AUTHOR]

This paper examines how non‐marine thrombolites are formed through a complex, multiphase process of microbial framework construction, erosion, cementation, recrystallization and episodes of internal sedimentation. Recognition of such phases of thrombolite construction provides a framework for the interpretation of the fluctuating environmental conditions leading to their formation. Microbialite frameworks are examined in detail from the Purbeck Limestone Group and their affinities and palaeo‐environmental significance assessed. Three types of thrombolite, one stromatolite and a leolite are described and interpreted. The thrombolite frameworks include: a peloidal mesoclotted type, a thrombolite constructed by the filamentous alga Cladophorites and a type with concentrically laminated micritic mesoclots. Physical and chemical erosion led to extensive early cavity formation within the frameworks. Early calcite rim cements with associated spherulites then developed over the microbial frameworks and these were reworked into cavities. Frameworks were also replaced by chalcedonic quartz and calcite spherulites. Internal sediments comprise peloids, intraclasts and brackish‐water molluscs and ostracods, together with their debris. The thrombolites grew in moderate‐energy to high‐energy shallow, lacustrine, microbial mounds whereas stromatolites occurred in deeper‐water settings. A brackish‐water, lacustrine setting is indicated by the preserved macro‐biota, microbes, absence of charophytes and syndepositional evaporites, and negative stable carbon and oxygen isotope ratios. Strontium isotopes suggest that the carbonate‐rich waters were fed from erosion of Mid–Lower Jurassic limestones on the western basin margin with possible mixing with waters from nearby uplifted Upper Jurassic limestones and with Late Jurassic seawater. The research indicates that non‐marine thrombolites have a complex, multiphase origin resulting in a diverse succession of textures and structures relating to microbially induced and influenced construction, dissolution, cementation, recrystallization and mineral replacement which have not been previously recorded and indicate the major differences between marine and non‐marine thrombolites. [ABSTRACT FROM AUTHOR]

The geometry, kinematics and dynamics of fold‐and‐thrust belts are strongly influenced by the mechanical behaviour of the basal décollement. However, many fold‐and‐thrust belts also include mechanically weak lithologies such as evaporites and marls or mudstones at different levels within the shortened stratigraphy. The kinematics and dynamic evolution of these thrust belts are controlled by the mechanical behaviour both of the basal décollement and of the weak units embedded within the overlying stratigraphic succession. In the Zagros fold‐and‐thrust belt (ZFTB), the shortened sedimentary cover is between 7 and 12 km thick and mechanically weak lithologies compartmentalize the stratigraphic column at shallow and intermediate levels. In this paper, satellite, field and seismic data from the Kurdistan Region of Iraq are used to identify structures of different sizes and surface traces. The observations are used to underline the role of mechanically weak horizons within the Zagros stratigraphy and the decoupling of deformation both laterally and with depth in the belt. The decoupling between shallow and deeper structures observed in seismic profiles from the Kurdistan Region of Iraq is also reported from field observations from the Iranian part of the Zagros fold‐and‐thrust belt, where folds with different surface traces occur. Decoupling between shallow and deep layers by incompetent lithologies at intermediate depths (e.g. marls, mudstones and evaporites) results in the formation of disharmonic folds. The geometry, size and location of such folds may differ between outcropping and subsurface structures. Decoupling may have a significant impact on hydrocarbon exploration in different parts of the Zagros fold‐and‐thrust belt due to potential offsets between outcropping and subsurface structures and their associated traps. [ABSTRACT FROM AUTHOR]

The objective of this paper is to study the hydrochemical characteristics of Lake Dayet Erroumi (Khemisset, Morocco). Three sampling campaigns were carried out in April, July and November 2019. The temperature, pH and electrical conductivity were measured in situ using Hanna Instruments HI 98280. Concentrations of calcium, magnesium, carbonate, bicarbonate and chloride were analysed by the volumetric method. The atomic absorption technique was used to determine sodium, potassium, nitrate and sulphate. The physico-chemical analysis of the water indicates that the pH is basic. The nitrate and sulphate concentrations show that the water is of good quality according to Moroccan surface water guidelines. Furthermore, the hydrochemical facies of water is of the sodium-chloride type according to the Piper diagram. The value of the electrical conductivity indicates that the lake water has high salinity. The high mineralization of water is explained by the leaching from evaporitic rocks in the region. The principal component analysis shows that the spatial and temporal variation in salinity constitutes the major phenomenon of the hydrochemical characteristics of this lake. Salinity varies inversely with the pH value. The salinity of the water is controlled by abiotic factors (rain and evaporation). However, other parameters (pH, nitrate, carbonate and bicarbonate) depend on biotic factors. Evaporation plays a crucial role in the seasonal variation of the water chemical composition. During wet seasons, the mineralization of water decreases due to dilution by rainwater and the water level of the lake rises (high water period). During dry seasons, lake water evaporates and consequently the mineralization of the water increases, which explains the increase in salinity during the low water period. [ABSTRACT FROM AUTHOR]

Cu and Fe skarns are the world's most abundant and largest skarn type deposits, especially in China, and Au‐rich skarn deposits have received much attention in the past two decades and yet there are few papers focused on schematic mineral deposit models of Cu–Fe–Au skarn systems. Three types of Au‐rich deposits are recognized in the Edongnan region, Middle–Lower Yangtze River metallogenic belt: ∼140 Ma Cu–Au and Au–Cu skarn deposits and distal Au–Tl deposits. 137–148 Ma Cu–Fe and 130–133 Ma Fe skarn deposits are recognized in the Edongnan region. The Cu–Fe skarn deposits have a greater contribution of mantle components than the Fe skarn deposits, and the hydrothermal fluids responsible for formation of the Fe skarn deposits involved a greater contribution from evaporitic sedimentary rocks compared to Cu–Fe skarn deposits. The carbonate‐hosted Au–Tl deposits in the Edongnan region are interpreted as distal products of Cu–Au skarn mineralization. A new schematic mineral deposit model of the Cu–Fe–Au skarn system is proposed to illustrate the relationship between the Cu–Fe–Au skarn mineralization, the evaporitic sedimentary rocks, and distal Au–Tl deposits. This model has important implications for the exploration for carbonate–hosted Au–Tl deposits in the more distal parts of Cu–Au skarn systems, and Fe skarn deposits with the occurrence of gypsum‐bearing host sedimentary rocks in the MLYRB, and possibly elsewhere. [ABSTRACT FROM AUTHOR]

Temperature increases and creep in saline rocks can cause annular pressure buildup (APB), presenting a significant challenge in oil well operations, particularly in deep and ultra-deep pre-salt fields. This paper proposes a one-dimensional axisymmetric multilayer thermomechanical model that accounts for the influence of evaporite layers and thermomechanical effects on APB. We developed a finite element model that integrates heat transfer and thermomechanical interactions, utilizing a double deformation mechanism as a constitutive model to represent the viscous behavior of the rock formation. Additionally, this model enables the iterative calculation of fluid properties based on temperature and pressure conditions. To validate the model, we conducted case studies using widely adopted commercial finite element software. Its consistent results provide a deeper understanding of the pressure increases caused by the influence of saline rock and thermal effects, offering valuable insights into the safe and efficient operation of oil wells using a model with reduced computational complexity. [ABSTRACT FROM AUTHOR]

Under nonequilibrium conditions, inorganic systems can produce a wealth of life-like shapes and patterns which, compared to well-formed crystalline materials, remain widely unexplored. A seemingly simple example is the formation of salt deposits during the evaporation of sessile droplets. These evaporites show great variations in their specific patterns including single rings, creep, small crystals, fractals, and featureless disks. We have explored the patterns of 42 different salts at otherwise constant conditions. Based on 7,500 images, we show that distinct pattern families can be identified and that some salts (e.g., Na2SO4 and NH4NO3) are bifurcated creating two distinct motifs. Family affiliations cannot be predicted a priori from composition alone but rather emerge from the complex interplay of evaporation, crystallization, thermodynamics, capillarity, and fluid flow. Nonetheless, chemical composition can be predicted from the deposit pattern with surprisingly high accuracy even if the set of reference images is small. These findings suggest possible applications including smartphone-based analyses and lightweight tools for space missions. [ABSTRACT FROM AUTHOR]

In this paper, an experimental investigation on the heat transfer of saturated water falling film on a single horizontal plain tube is presented. The water film falling on the outside of the tube has been heated by the condensing steam flowing in the tube, and the heat transfer coefficient between the water film and the steam has been measured. Experiments were performed at saturation temperatures of liquid film and steam as 58°C and 61°C, and 61°C and 65°C, a tube pitch of 57.16 mm, heat fluxes from 10 to 50 kW m-2, and film flow rate per unit of length of the tube up to 0.12 kg m-1 s-1. Brass plain tubes with external diameters of 25.4 mm and lengths of 950 mm were used in the experiments. The experimental results show that the heat transfer coefficient increases with the increasing film flow rate and heat flux, and the quality of vapor has an obvious influence on the heat transfer performance of falling film evaporation. The coupling of condensation and evaporation heat transfer inside and outside the tube is investigated qualitatively in this paper. [ABSTRACT FROM AUTHOR]

The homogenization of primary inclusions was key to reconstructing the specific conditions that lead to evaporite formation, determining brine temperature, and indirectly indicating the climate during the Badenian salinity crisis in the Carpathian region. They present the results of geochemical studies of Late Cretaceous potassium salts [[7]], infer the evaporite basin evolution from stable isotope studies [[8]], and make paleogeographic inferences regarding the Late Cretaceous period in southern China [[9]]. In his excellent and complete compendium "Evaporites" [[1]], John Warren defines evaporites as salt rocks that were originally precipitated from a saturated surface or subsurface brine under hydrology conditions, driven by solar evaporation. [Extracted from the article]

The present paper focuses on the description of the main evaporite karst areas of Albania, and on their environmental problems. Even though the majority of the karst areas in Albania is represented by carbonates, evaporites crop out significantly at several sites, and deserve a specific attention for their morphological, karstic and speleological peculiarities. Vulnerability of karst is well marked by pollution and degradation problems in regions such as Dumre (central Albania), where some tens of lakes of karst origin are present in the Permian–Triassic evaporites. Water pollution with negative effects on the local ecosystems, and anthropogenic changes of the natural karst landscape in the last century resulted in intense environmental degradation at Dumre. Messinian evaporites crop out in the Kavaja area (near the Adriatic coast), and at other sites in central-southern Albania. In these areas, surface karst morphology is characterized by a number of dolines, ponors and blind valleys, which often correspond to inlet points of subterranean drainages and caves. Notwithstanding these peculiarities, and the relevance of the area for biospeleological studies, many caves have been destroyed by quarrying activities, resulting in severe losses to the natural heritage. Following a general description of the evaporite karst areas of Albania, the paper focuses on the present situation of the evaporites in the country, which is frequently affected by degradation and environmental losses in the karst landscape, and pollution of the aquifers. [ABSTRACT FROM AUTHOR]

This paper describes and interprets the mineral and facies assemblages that occur in carbonate-evaporite shallow lacustrine deposits, considering the importance of the processes pathway (i.e. dolomitization, gypsum calcitization and silicification). The Palaeogene deposits of the Deza Formation (Almazán Basin, central-northern Spain) are selected as a case study to determine the variety of physicochemical processes taking place in carbonate-evaporite shallow lakes and their resulting diagenetic features. Dolostones are the predominant lithology and are composed mainly of dolomite with variable amounts of secondary calcite (5 to 50%), which mainly mimic lenticular gypsum (pseudomorphs). Five morphological types of dolomite crystal were identified as follows: dolomite tubes, dolomite cylinders, rhombohedral dolomite, spheroidal and quasi-rhombohedral dolomite, and cocoon-shaped dolomite. The dolomite cylinders and tubes are interpreted as the dolomitized cells of a widespread microbial community. The sequence of diagenetic processes started with growth of microlenticular interstitial gypsum in a calcareous mud deposited on the playa margin mudflats, and that sometimes included microbial sediments. Immediately following growth of gypsum, dolomite replaced the original calcite (or possibly aragonite) muds, the microbial community and the gypsum. Partial or total replacement of gypsum by dolomite was related mainly to the biomineralization of endolithic microbial communities on gypsum crystals. Later calcitization took place under vadose, subaerial exposure conditions. The development of calcrete in distal alluvial settings favoured the release of silica and subsequent silicification on the playa margin mudflats. Stable isotope compositions of calcite range from −9·02 to −5·83‰ δ13 CPDB and −7·10 to 1·22‰ δ18 OPDB; for the dolomite, these values vary from −8·93 to −3·96‰ δ13 CPDB and −5·53 to 2·4‰ δ18 OPDB. Quartz from the cherts has δ18 OSMOW values ranging from 27·1 to 31·1‰. Wide variation and relatively high δ18 OSMOW values for dolomite indicate evaporitic and closed hydrological conditions; increased influx of meteoric waters reigned during the formation of secondary calcite spar. [ABSTRACT FROM AUTHOR]

This paper examines evaporated deposits of gypsum known as the Ulukışla Evaporites located in the Ulukışla Basin, central Anatolia, Turkey. The Late Eocene compression between the Eurasian and Afro-Arabian plates formed numerous shallow epicontinental basins in SE central Anatolia. During this period, the Ulukışla Basin was a shallow marine environment. The composition of the Ulukışla Basin indicates that gypsum and stromatolite were deposited due to an arid climate and sea level oscillation between 37.25 and 38.52 Ma. Oxygen, sulfur, and strontium isotopes and the geochemistry of the evaporated rocks were measured to understand the paleoenvironment of this formation. Trace element analyses of Fe, K, Mg, Na, Mn, Sr, Ni, and Cu from the gypsum samples showed very high variability. The average K/Na, Sr/Ca, and Mg/Na were measured to be 0.4, 2.35, and 2.9 %, respectively, which indicates that the Ulukışla gypsum lies in a formerly hypersaline environment. Sr/Sr, O, and S isotope ratios indicate that the gypsum was deposited in marine water then mixed with fresh continental water. [ABSTRACT FROM AUTHOR]

Chemical deposits inside evaporite (gypsum, anhydrite and halite) caves are far less common than those developed within limestone or volcanic cavities. Moreover they exhibit a lower scarce mineralogical variability due to several reasons, the most important of which are: 1) calcium sulfate and sodium chloride are by far less reactive than calcium carbonate; 2) evaporite outcrops normally have a low mineralogical variability within the cave recharge areas. Therefore these karst environments were less investigated from this point of view in the past: no general paper exists on speleothems developing in halite and anhydrite caves until present, while the last printed one on gypsum (and anhydrite) karst appeared around 20 years ago. Several mineralogical studies were carried out in the last decades in caves from different evaporite areas proving that some of them host peculiar minerogenetic mechanisms, which are, at the moment, exclusive for these areas, and sometimes also brought to light to rare or even new cave minerals. In the present paper, together with an overview on all the actually known minerogenetic mechanisms active within the evaporite caves, the related chemical deposits and speleothems are shortly described. Far from being exhaustive, the recent mineralogical research on evaporite caves puts in evidence their unexpected richness in peculiar hosted speleothems and rare cave deposits. Seven out of the fifty known evaporite cave minerals, and around 10 speleothem types/subtypes are exclusive to these environments. Taking into account that only a few evaporite areas have been, so far, studied, it is highly probable that in the near future many more new cave deposits will be discovered, thus increasing the mineralogical interest of these unique caves. [ABSTRACT FROM AUTHOR]

Sinkholes are common in the Friuli Venezia Giulia (FVG) Region (NE Italy), where the presence of karstifiable rocks favours their occurrence accelerated by intense rainfalls. Their existence has been reported since the end of the 1800s along the Tagliamento Valley, in correspondence with the mantled evaporites (gypsum). Furthermore, tens of evaporite sinkholes have been documented on the reliefs adjacent to the village of Sauris and along the narrow W-E-oriented valleys, where regional faults have played a major role in their spatial distribution. This paper reports for the first time an inventory of the sinkholes affecting the evaporites of the FVG Region. These phenomena were mapped and categorised using a genetic classification. The main output is an A0-format map, which incorporates a 1:50,000 scale Sinkhole Inventory Map (SIM). The SIM encompasses 552 sinkholes. The cover suffosion sinkholes are the most abundant, followed by bedrock collapses. There is a clear prevalence of the circular shape (65%) over other shapes. Diameters are 1–140 m, with depths ranging 0.1–40 m with a mean value of 4.5 m. The SIM can motivate regional planning authorities to perform further investigations aimed to understand the geomorphological evolutions of these phenomena. [ABSTRACT FROM PUBLISHER]

A recent paper by Caruso et al. (2015) dealing with the Calcare di Base of Sicily and Calabria reintroduced an earlier idea that onset on the Messinian salinity crisis is diachronous. The paper provided a stratigraphic correlation of five sections together with the reference section of Falconara and Gibliscemi (Sicily) in order to establish the diachronous nature of restricted saline conditions. In our opinion their conclusions are not supported by the data, and the paper contains some stratigraphic errors that depend on a flawed presentation of the main stratigraphic concepts provided over the past few years covering the deposits of the Messinian salinity crisis in Sicily. In this discussion we challenge the stratigraphic conclusion of Caruso et al. (2015) holding that: a) they did not fully consider the different types of deposits included in the Calcare di Base unit and consequently did not recognize the large scale unconformity at the base of the brecciated limestone (Calcare di Base type 3); b) they did not provide univocal criteria for the definition of the onset of the Messinian salinity crisis; c) they hold the idea that the onset of the salinity crisis must be coincident with the onset of the evaporites, concept which is not necessarily true; d) they arbitrarily correlated different evaporitic deposits formed during different stages of the MSC; e) they provided a stratigraphic correlation of the study sections and their tuning with the insolation curve that lacks of reliable stratigraphic constraints. Consequently, they have presented an unreliable schematic evolution of the Caltanissetta basin. [ABSTRACT FROM AUTHOR]

Manzi et al. (in press) took the opportunity offered by our paper to repeat again all the set of ideas supporting an interpretative model of the Messinian Salinity Crisis (MSC), a model they assert to be valid for the whole Mediterranean basin. What emerges from reading this long comment may be summarized in one criticism of our article: we have not systematically applied their interpretative model to our data! The aim of our paper was not to promote their ideas, but to submit the results of more than 20 years of field studies and petrographical and geochemical analyses on Sicilian and Calabrian sequences of the Messinian “Calcare di Base”. It is out of our purpose to enumerate again in this reply the data and interpretations we have developed in our paper, which disagree with their model and rule out most of their propositions. Thus, we will not reply in detail to this repetitive stream of ideas supporting their model. But we want to respond to some general and unfair comments, which are often far away from objectivity, and rectify some inaccurate assertions about the description of some sections. [ABSTRACT FROM AUTHOR]

The presence of trace elements in water for domestic supply or irrigation could pose a significant toxic risk for health, due to direct consumption or bioaccumulation through the ingestion of vegetables irrigated with this water. This paper studies the presence of 41 trace elements plus nitrate and bromate in groundwater, using a multivariate statistical tool based on Principal Component Analysis and a geostatistical Kriging method to map the results. Principal Component Analysis revealed 11 significant principal components, which account for 82% and 81% of the total variance (information) respectively for the two dates analysed. Ordinary Kriging was applied to draw maps of the trace elements and PC scores. This research breaks new ground in terms of the large number of parameters used and in terms of the analysis of spatiotemporal variations in these parameters. The results obtained indicate that PC1 represents the natural quality of the aquifer (geogenic) and that there is little change in the average PC1 value between the two dates studied (June near the peak recharge point and November at the end of summer). Agriculture is the human activity that causes the greatest variations in the quality of the groundwater due to the use of fertilizers and due to watering crops with wastewater (PC7_J and PC5_N, June and November, respectively). Other elements of industrial origin, which are dangerous for human health, such as Pb, Cu and Cd, are grouped together in other principal components. The results show that the decline, or even complete absence, of natural recharge during the summer months leads to an increase in the TEs produced by human activity. This indicates that a temporary reduction in the natural recharge could worsen the quality of water resources. Based on the interpretation of the estimated maps, a synthetic map was created to show the spatial distribution of the areas affected by geogenic and anthropogenic factors. Studies with a global approach like this one are necessary in that the possible sources of pollution that could alter the quality of the groundwater and the amount of trace elements and other potentially harmful substances could increase as time goes by. The main advantage of the methodology proposed here is that it reduces the number of parameters, so simplifying the results. This makes it easier to interpret the results and manage the quality of the water. • PCA and geostatistical methods were used to establish the spatiotemporal variations in 41 trace elements. • A complex spatial relationship between anthropogenic and geogenic activities was reduced to just six categories. • The anthropogenic activity with the greatest impact on groundwater quality is agriculture. • Evaporitic rocks were the main cause of geogenic contamination of the groundwater. [ABSTRACT FROM AUTHOR]

Engineering applications pose major challenge in designing structures that are safe, durable, and sustainable in various environmental situations. The slake durability index (SDI) test is commonly used to evaluate weak rock disintegration, such as evaporates, which are widely found in the Abu Dhabi area near the foundation levels, encountering construction challenges due to their disintegration. This study intends to provide insight into the disintegration characteristics of evaporitic rocks in the Abu Dhabi region under acidic and alkaline environmental conditions. Distilled water and groundwater which was collected from the study area is used as slaking fluids. As a result, rock blocks from the Abu Dhabi region, which is divided into four zones, were collected, and six sets of representative SDI test samples for each zone were prepared and tested using slaking fluids of pH values 2, 4, 6, 8, 10, and 12, as well as distilled water and groundwater. In addition, the macroscopic and microscopic (thin section, X-ray diffraction, X-ray fluorescence, and scanning electron microscopy) descriptions of representative samples from each zone were carried out. According to the findings, the overall average slakes durability weight loss of evaporates lies in the range of 60–72 wt% and could be classified as medium durably for Zones 1 and 4 under the basic environment, and for Zones 2 and 3 under the acidic environment. Thus, this study delivers the detailed explanation about the slaking characteristics of evaporitic rocks under various pH level conditions for engineers and decision makers to overcome degradability problems. [ABSTRACT FROM AUTHOR]

This paper reports the first interpretative field map and stable isotope geochemistry of an exhumed Miocene inlier with conical mud volcanoes in a Persian (Arabian) Gulf salt flat (sabkha). In Kuwait, the siliciclastic low-heat flow margin of the northern gulf sector produced sedimentary conditions with numerous multilayered, unstable density gradients that were highly susceptible to recording liquefaction effects. The geotechnical characteristics of the sabkhas and the effects of local seismic activity resulted in ideal conditions in marginal sediments of Kuwait Bay, well suited for the development of deformation features. Three-dimensional, pseudo-biohermal exposures exhibit ellipsoidal pillows with craters separated by fluidized channels of chaotic orientation. The size and morphology of these structures together with co-genetic mud volcanoes are strongly influenced by sedimentary factors such as density gradients and tectonic events such as localized seismic activity, which caused mixing of fluids. Diapirs emerged concurrently with syn-sedimentary deformation, and the mud injection responded to episodic seismic activity. Interpretation based on previously published reflux models such as evaporative pumping and seawater flooding of coastal sabkhas is not applicable in this case. Rather, a model of focused ascent of brine initiated by episodic seismicity is proposed. Swarms of mud volcanoes represent new abiotic sedimentary features in sabkhas, but the per-ascensum nature of the fluid offers some comparisons to siliceous hot-water vents in south-eastern Brazil. [ABSTRACT FROM AUTHOR]

This paper investigates the origin of solutes within the groundwaters of the Monturaqui–Negrillar–Tilopozo (MNT) aquifer system within the high Andes of the Atacama Desert that discharges into the Salar de Atacama. Key questions include the relative significance of volcanic hydrothermal processes and evaporitic brine recycling over solute supply as well as the pathways of solute ingress to the MNT aquifer system. Groundwaters were analysed for elemental (major, minor and trace) and isotopic (δ 18 O/δ 2 H; δ 13 C–DIC; δ 34 S–SO 4 ; 87 Sr/ 86 Sr) constituents to which various hydrochemical and multivariate statistical methods have been applied. Groundwaters are all classified as thermal and show increasing temperatures (27–35 °C) and concentrations of HCO 3 (4.4–10.4 mmol L − 1 dissolved inorganic carbon [DIC]) with increasing proximity to Volcano Socompa resulting from an increasing mass flux of steam and magmatic CO 2 ( p CO 2 = 0.016 to 0.10 atm; δ 13 C–CO 2 = − 9.3 to − 3.6‰ (V-PDB)) boiled off a deep hydrothermal reservoir. Superimposed upon this gradational and relatively smooth spatial increase in heat and mass flow is a sharp, structurally controlled, increase in TDS (826–3632 mg l − 1 ) and a concomitant change in δ 34 S–SO 4 (+ 0.79 to 4.9‰ (V-CDT)) and 87 Sr/ 86 Sr values (0.707375–0.706859) associated with the inflow of evaporitic solutes. Evaporitic inputs are chemically and isotopically distinct from localised secondary hydrothermally derived solutes with major, minor and trace element data suggesting an origin within a highly oxidising, alkaline, evaporitic lake receiving dilute inflows enriched in volcanic/fumarolic sulfur mineralisation probably from volcanoes Socompa, Salín or Pular that delimit the eastern topographic extent of the aquifer system. The conceptual model presented in this paper proposes that basal leakage of evaporitic brines from active salar(s), within the high altiplano/volcanic arc, are actively entrained by sub-regional groundwater flow and conveyed to the MNT aquifer system where they mix with solutes derived from localised secondary hydrothermal gas–water–rock interaction. This work provides detail on the origin and processes controlling the solute composition of groundwater inflows to the Salar de Atacama within the volcanically active and hyperarid Atacama Desert and may be of significance to conceptual models of evaporitic brine evolution, recycling of evaporitic brines and hydrothermalism in arid regions. [ABSTRACT FROM AUTHOR]

The Sivas Basin in Turkey displays in its central part an Oligo-Miocene halokinetic province which acts as a major outcrop analogue to study salt-sediment interactions. Based on field geology observations, the present paper focuses on the geometry and sedimentology of several minibasins having the particularity of being mainly filled by gypsiferous deposits. Such type of evaporite-rich minibasins remain difficult to identify and are poorly studied in other halokinetic provinces. In the Sivas Basin, the evaporites were recycled from diapiric salts and precipitated in saline ponds emplaced above deflating diapiric stems. Diapir deflation resulted either from local transtensive strain, cessation of diapir feeding and/or subsurface dissolution of the diapiric salt. Minibasin subsidence was likely enhanced by the fast emplacement rate of the capping evaporites, together with the high density of the depositional sulfates compared to the diapiric halite. The evaporite-rich minibasins stand out from their surrounding siliciclastic counter-parts by their small dimension (lower than 1 km-wide), their encased teardrop shape, and their high internal deformations. The later include well-developed halokinetic sedimentary wedges, aerial mega-slumps or inverted flaps. Such structural features probably resulted from the ductile rheology of the evaporite infill and the complex pattern of downbuilding. Although secondary evaporitic minibasins have never been identified in other ancient halokinetic settings, our study highlights that they could developed in any evaporitic environments, coastal or continental, such as in the Precaspian Basin. The secondary minibasins described here can also act as field analogues of other primary evaporite-rich minibasins already suspected in salt giant basins (e.g. in the Santos Basin, Brazil). • Oligo-Miocene evaporite-rich minibasins (EMB) developed on deflating diapirs in the Sivas Basin. • EMB filled by gypsiferous deposits recycled from the diapirs and precipitated in saline lacustrine environments. • EMB with small dimension (lower than 1 km-wide), encased shapes, and high internal halokinetic deformations. • Inferred influence of the density, rheology and sedimentation rate of the depositional sulfates for EMB development. [ABSTRACT FROM AUTHOR]

The Fengcheng Formation in the Mahu sag of the Junggar Basin was primarily composed of detritus, pyroclastic material, carbonates, and evaporites. In order to establish the diagenesis pathways of the Fengcheng Formation, some methods of polarized light microscope, SEM, CL, EPMA, LR, and fluid inclusion analysis were applied to discuss the diagenesis process. The results showed the following: (a) The formation of an alkaline lake was the result of the influence of a high concentration of sodium-rich sources, and it led to the preservation of alkaline minerals in the stratum. (b) After the sediments were buried, three mineral assemblages were formed in the Fengcheng Formation, which are carbonate mineral assemblages (i.e., calcite + ferreous dolomite), reedmergnerite and carbonate mineral assemblages (i.e., reedmergnerite + calcite + ferreous dolomite), and reedmergnerite and alkaline mineral assemblages (i.e., reedmergnerite + shortite + trona), respectively. (c) According to the homogenization temperature of reedmergnerite primary fluid inclusions, the alkaline diagenesis of Fengcheng Formation was divided into an early stage (≤100 °C) and a middle stage (>100 °C), respectively. The earlier stage is marked by the formation of ferrous saddle dolomite, quartz dissolution, and the agglutination of laumontite. These processes occurred under normal burial conditions. The latter is marked by the reedmergnerite's appearance, which is correlated with the deep hydrothermal activity controlled by faults. (d) Based on sedimentary and diagenetic factors, including climate, provenance, diagenetic surroundings, and the action of subsurface fluid, the alkaline deposition-diagenesis model for shale series in four stages of the Fengcheng Formation was established. [ABSTRACT FROM AUTHOR]

In northern Switzerland, Middle Muschelkalk evaporites (Zeglingen Formation) were deposited under arid conditions in the southernmost part of the epicontinental Central European Basin during times of reduced inflow of sea water from the Tethyan realm. Because of their marginal position in the basin, direct and detailed correlation of Muschelkalk sediments of northern Switzerland with equivalent strata in interior parts of the basin is not straightforward. Based on detailed sedimentological logging of 640 m of drill cores from ten wells in northern Switzerland, 22 lithofacies and 10 lithofacies associations were distinguished for the Middle Muschelkalk evaporites. High-resolution regional correlations of gamma-ray logs record substantial thickness variation of the evaporites. Locally, dissolution was recognized by visual core examination that could be dated to Middle Triassic times and that was likely related to subsurface fluid flow along deeper seated faults. In combination with the regional thickness variation, the dissolution phenomena suggest a tectonically active depositional setting in the Middle Triassic. Middle Muschelkalk evaporites consist of nine types of mainly auto-cyclic shallowing- or brining-upward mini-cycles which form a correlatable succession of five distinct 4th order cycle-sets. Despite the tectonically active depositional environment, most lithofacies encountered appear to have nearly flat bounding surfaces. Thus, marine transgressions flooded wide areas nearly simultaneously. The corresponding deposits serve as reference levels to tie the peripheral facies of northern Switzerland into the supra-regional context. [ABSTRACT FROM AUTHOR]

The widespread occurrence of evaporites is an important feature of the Middle Triassic Leikoupo Formation in the Sichuan Basin, southwest China. Their origins and geological implications, however, have not been well addressed so far. The issues were preliminarily discussed in this paper. The evaporites include two genetic types. The first is found predominantly in the first to third members of the formation, exhibits a uniform lateral distribution, and presents fairly thin (<5 m) individual layers with a cumulative thickness of <50 m. These evaporites show predominantly laminar bedding with massive beds locally, and their origin is inferred to be from lagoon deposition. The second genetic type was formed later, and occurs from the middle part of the third member to the middle part of the fourth member of the formation. The lithology includes massive gypsum rocks and halites. There is marked variation in both the thickness and lateral distribution of the second type of deposits, and they are inferred to have been deposited in evaporitic depressions whose depositional centers were located in the western and northern basins. These results have implications for the understanding of the region's tectonics. The tectonic stress field of the Sichuan Basin during the Middle Triassic was subject to a transition from extensional to compressive stress. The time interval represented by the first member to the lower part of the third member of the formation encompassed a stable tectonic stage during which the transition was initiated. In contrast, the time interval represented by the middle part of the third member to the middle part of the fourth member was characterized by an active tectonic phase. During that time, the NW-SE and NE-SW trending stresses became activated, resulting in the formation of new depositional centers. Strong evaporation led to the rapid deposition of evaporites in structural lows. The findings provide a new understanding of the geology of the Lower Triassic Leikoupo Formation in the Sichuan Basin. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Engineering Geology & the Environment is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most subsurface rock models consider salt bodies as homogenous masses and set to evaporite minerals constant values of elastic properties such as density, compressional and shear velocities, Young's modulus and Poisson's ratio. Lithological analyzes of outcrops and wells indicate that evaporites present large vertical and lateral heterogeneities. Recent studies have demonstrated that the knowledge of the elastic properties of rock salt can substantially benefit velocity modeling, seismic imaging, reservoir geomechanical analysis, prediction of wellbore stability and calculation of optimum fluid weight. However, few papers document the spatial estimation of elastic properties for salt formations. We propose an approach to characterize the internal structures of the salt bodies in the Santos Basin, offshore Brazil, using well and 3D seismic data. It starts with a rock-physics analysis at well-log scale, which reveals that the elastic properties of rock salt are highly correlated. Once the relationships of the elastic properties are established, we explore the functionality of the empirical equations as property predictors. We demonstrate that the elastic properties can be empirically estimated from compressional velocity. The comparison between the estimated and the measured well logs validates the estimation. Then, we perform the seismic inversion to generate the spatial distribution of the acoustic impedance. We derive compressional and shear velocities, density, Young's modulus and Poisson's ratio volumes by applying the empirical equations to the acoustic impedance volume. The blind well points out that, through this workflow, the seismic data can successfully predict the elastic properties of the salt formation in undrilled portions. • Studies of in-situ elastic behavior of evaporites. • Formulation of new empirical equations as property predictors. • Compaction has null influence on the elastic properties of rock salt. • Combination of seismic inversion and rock physics for quantitative characterization. • Review of multidisciplinary applications of elastic properties of rock salt. [ABSTRACT FROM AUTHOR]

Construction of the great Upper Gotvand Dam in the Karun River, Iran, with an impoundment capacity of 4.5 billion cubic meters, has resulted in an environmental disaster: accumulation of 66.5 million metric tonnes of dissolved salt in the reservoir and a dramatic increase in the salinity of the reservoir water up to 200 g/L. This paper aims to identify and assess the main sources of the salinization of the reservoir water integrating multiple data: (1) geological and geomorphological evidence; (2) continuous vertical records of electrical conductivity at 11 stations along the reservoir; (3) total dissolved solids and major ion concentrations of 108 water samples at 58 sampling stations; (4) δ18O, δ2H in 35 water samples and δ37Cl in 16 water samples from the reservoir and surrounding rivers and springs. Geological and geomorphological evidence, hydrogeochemical data and isotopic signature reveal that halite dissolution is the main cause of salinization in the Gotvand Reservoir. The results show that salt dissolution in the Gachsaran Formation (especially at Anbar Ridge), which was under-estimated in the study phase of the project, has provided about 86 per cent of the dissolved salt accumulated in the reservoir over a 2-year period since the impoundment of the reservoir in 2011. Image 1 • Significant salt has accumulated in the reservoir of the Gotvand Dam. • δ18O, δ2H and δ37Cl stable isotope techniques were used to identify salinity sources. • Main cause of the reservoir salinity is halite dissolution of an evaporite formation. [ABSTRACT FROM AUTHOR]

This paper focuses on Messinian Salinity Crisis (MSC) evaporites in the Cyprus Arc (eastern Mediterranean) using high-resolution reflection seismic and multi-beam data. The results shed new light on the Miocene to Present tectonic evolution of this area and contribute to our general knowledge of the MSC in a deep basin setting. The evaporites and overlying formations show a complex deformation pattern due to a combination of thick-skinned plate-tectonic convergence and thin-skinned disharmonic deformation related to the mobile evaporite-bearing unit. Several MSC markers are identified and precisely mapped: the base of the MSC unit is a 'decollement' level, whereas the top is clearly identified as a toplap surface. Intra-MSC markers and two MSC subunits are identified and mapped over the entire study area. The geometry of MSC markers shows that the lower MSC subunit was deposited in a relatively quiet tectonic setting. The nature of the anisopachous upper unit indicates a syn-depositional phase of large-scale plate-tectonic activity. A thin-skinned phase of compressional deformation during the Late Miocene affected the entire MSC unit, overlain by undeformed Pliocene-Quaternary layers. A second thin-skinned phase, well expressed in the bathymetry, occurred from the Pliocene to Recent, resulting in extensional gravity-gliding within the evaporites and the Pliocene-Quaternary sequence. We show that the MSC had a dramatic impact on the regional structure. For instance, the erosive nature of the top of the MSC unit is linked to the desiccation episode rather than to the cessation of tectonic activity. This particularly strong and short-lived erosion may have been enhanced by the regional effects of the MSC, owing to differential uplift/subsidence caused by the drawdown. The evaporites are essential markers for constraining the tectonic framework, provided that active deformation can be distinguished from passive gliding associated with extensional/contractional deformation. [ABSTRACT FROM AUTHOR]

- Weathering of meteorites at the scale of the entire Antarctic Search for Meteorites program population is studied by analyzing the recent version of the online Antarctic meteorite classification database that includes information about 15,263 meteorites. This paper updates, supplements, and expands on the last Antarctic meteorite weathering census by , Meteoritics 23:151-159). On average 5% of all Antarctic meteorites are indicated as evaporite bearing in the Antarctic Meteorite Database. Evaporite formation depends on compositional group. Evaporites are much more common on C chondrites than on ordinary chondrites, supporting previous findings. Ordinary chondrites of petrologic type 3 more often have evaporites on their surface than meteorites of other petrologic types. Contrary to previous findings, there is no apparent relation between evaporite formation and meteorite rustiness. Some meteorite-bearing fields influence the frequency of evaporite-mineral formation on meteorites. The influence of location is apparently related to differences in environmental conditions, most probably microclimate or/and hydrologic conditions. There is no relation between abundance of evaporite-bearing meteorites and distance from the sea. Evaporite formation varies with year of collection; however, it was not possible to distinguish whether this is related to annual changes in environment or an artifact of sample categorization or curation. [ABSTRACT FROM AUTHOR]

In the Zagros orogenic belt in SW Iran, a 14 km thick sedimentary succession is decoupled from crystalline basement by the thick Infracambrian Hormuz complex. The complex consists of evaporites ('Hormuz salt') together with marls, sandstones, carbonates and volcanic rocks and is known from emergent salt diapirs in the Fars and High Zagros areas. In this paper, we document discrete pulses of halokinetic activity using seismic profiles, well data and recent field studies. The earliest phase of mobilization of the Hormuz salt occurred in the pre-Silurian. Later pulses of salt movement took place during opening of Neo-Tethys in Permo-Triassic times and during ophiolite obduction onto the NE Arabian plate margin in the Late Cretaceous. Halokinesis was intense during the Neogene Zagros orogeny when some salt plugs breached the surface. [ABSTRACT FROM AUTHOR]

The Salar de Atacama, located in Northern Chile, is a wide salt flat that is characterized by several salt lakes, which are locally called lagunas. The Laguna de la Piedra is one of the salt lake systems that is located in the northernmost sector of the Salar de Atacama. The present paper examines some physicochemical properties of the Laguna de la Piedra as well as the microbial diversity of the evaporite deposits. Under extreme desiccation and ambient UV flux, the evaporite deposits can create favorable endolithic microniches for the development of microorganisms. In the Laguna de la Piedra these deposits host a variety of halophilic microorganisms, which were investigated by using an optical and environmental scanning electron microscope (ESEM) as well as molecular diversity studies based on the small subunit ribosomal (SSU) rRNA of Bacteria, Archaea and Eucarya. We detected a single phylotype of halophilic archaea and a oxytrichid ciliate. Within the bacteria, a variety of Cyanobacteria, Bacteroidetes, Alpha-, Beta- and Deltaproteobacteria, as well as members of the candidate division TM6, were identified. [ABSTRACT FROM AUTHOR]

Titan is the only body, beside the Earth, where liquid is present on the surface in the form of lakes and rivers. Moreover, observations reveal that the shorelines of some lakes have retreated by several kilometers. It means that there exist conditions necessary for evaporites formation. In fact, Cassini observations suggest the existence of organic evaporites deposits. One subject of the paper is thermal convection in regolith covered with evaporite deposits. The next subject is the convection below bed of a lake or a river. Some difference of convection in these cases are found, e.g. different convective pattern. The difference of pattern of convection in regolith could lead to different convection patterns in the lake which could be observable. The last subject is the interaction of flow with grains of sediments. It is indicated that the convection in regolith could trigger saltation or motion of sediments at the bedload. [ABSTRACT FROM AUTHOR]

Field measurements of dielectric properties of hypersaline deposits were realized over an arid site located in Death Valley, CA. The dielectric constant of salt and water mixtures is usually high but can show large variations, depending on the considered salt. We confirmed values observed on the field with laboratory measurements and used these results to model both the amplitude and phase behaviors of the synthetic aperture radar (SAR) signal at C- and L-bands. Our analytical simulations allow reproducing specific copolar signatures observed in both Airborne SAR (AIRSAR) and Spaceborne Imaging Radar (SIR-C) data, corresponding to the saltpan of the Cottonball Basin. More precisely, the main objective of the present paper is to understand the influence of soil salinity as a function of soil moisture on the dielectric constant of soils and then on the backscattering coefficients recorded by airborne and spaceborne SAR systems. We also propose the copolarized backscattering ratio and phase difference as indicators of moistened and salt-affected soils. More precisely, we show that these copolar indicators should allow monitoring of the seasonal variations of the dielectric properties of saline deposits at both C- and L-bands. Because of the frequency dependence of the ionic conductivity, we also show that L-band SAR systems should be efficient tools for detecting both soil moisture and salinity, while C-band SAR systems are more suitable for the monitoring of soil moisture only. Through the study of terrestrial evaporitic environments by means of spaceborne SAR systems, our results could also be of great interest for defining future planetary missions, particularly for the exploration of Mars. [ABSTRACT FROM AUTHOR]

The Bochnia Salt Mine, presented in this paper, is situated ca. 40 km E of Cracow, in the southern part of the Neogene Carpathian Foredeep, close to the Carpathian edge. In this region the rock-salt deposits formed as a result of the Late Miocene folding and local tectonic thickening of Badenian evaporites. The Bochnia deposit, situated in the almost vertical N limb of the Bochnia Anticline, stretches ca. 7 km WE, but only 15-200 m NS. Salt mining in Bochnia began in the thirteenth c. and continued until 1990. The historic part of the mine, since 1995 operated by a company supplying health and tourism services, is an officially listed monument of historic heritage. Legal protection also comprises 27 sites of key value for the geology of the deposit. These documentation sites record the whole profile of the evaporite series and the adjacent beds, main and minor tectonic structures, as well as mineralogical curiosities, such as fibrous halite and enterolithic anhydrite. For some years, efforts have been made to enter the Bochnia Salt Mine, in 2008 visited by over 140 000 tourists, on the UNESCO World List of Cultural and Natural Heritage. [ABSTRACT FROM AUTHOR]