Halite Inclusions Research Articles

Calibration strategies for the elemental analysis of individual aqueous fluid inclusions by laser ablation inductively coupled plasma mass spectrometry

Using a combination of synthetic fluid inclusions in halite, microvolume aqueous solutions and National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 611 Glass, calibration graphs were established for the determination of elemental ratios in natural fluid inclusions by laser ablation–inductively coupled plasma mass spectrometry (ICP-MS). For simultaneous multi-element analysis, optimization studies demonstrate the necessity to adopt a compromise set of operating conditions since ICP-MS sensitivity (signal:background) may differ from element to element as a function of argon flow, radiofrequency power and spray chamber temperature. Synthetic fluid inclusions were prepared by crystallization from saturated sodium chloride solutions containing up to 13 major and minor cations. The microvolume calibration standards, ‘microwells’, consisted of small holes (3 × 3 × 2 mm3) drilled into plastic sheet, filled with a standard solution and hermetically sealed. In order to allow direct comparison between the different test materials, all the elements (Li, Na, Mg, K, Ca, Mn, Cu, Zn, Rb, Cs, Ba, Pb, B, Cl, Br) were ratioed to strontium. The relative standard deviations for the element ratios were generally better than 25%, indicating that the nature of the sample (salt, glass and aqueous solution) does not markedly affect the consistency of ablation or the efficiency of transfer between the ablation chamber and ICP torch. Element ratios for the synthetic fluid inclusions were linear over several orders of magnitude and in close agreement with those for the NIST SRM 611 Glass and microwell solutions, irrespective of inclusion size (20–100 µm) and depth in the sample (up to 80 µm). Statistical t-tests on the mean element ratios confirm that microwells and glasses constitute suitable alternatives to synthetic fluid inclusions for the calibration and routine analysis of natural fluid inclusions.

New quantitative approach in trace elemental analysis of single fluid inclusions: applications of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)

Laser ablation inductively coupled plasma mass spectrometry has been used for the in situ elemental analysis of individual fluid inclusions with artificially prepared fluid inclusions as external standards. Artificial fluid inclusions standards were prepared by drawing a standard solution of known composition into microcapillary tubes. An ICP-MS equipped with an Nd:YAG laser operating in the UV region (266 nm) was used for data acquisition. The laser was focused and fired on 25–30 µm spots on the microcapillary tubes until the fluid was reached. The content of the microcapillary tube then emptied and was transported with argon to the torch. The average volume of fluid released, per pulse of laser, was approximately 100 pl. Calibration curves were created by plotting signal intensity versus concentration. The long-term precision (RSD%) of measurements for Sr were 1.1–3.1% for a 1000 ppm solution, 2.7–4.9% for a 500 ppm solution and 3.1% for a 250 ppm solution. Similar measurements on the same solutions for Rb gave values of 1.9–2.3% for a 1000 ppm solution, 5.1–6.3% for a 500 ppm solution and 1.7% for a 250 ppm solution. The technique was tested on fluid inclusions in halite from the Palo Duro Basin, Texas, USA. The results show that concentrations for Sr range from 90 to 153 ppm, and for Rb from 98 to 100 ppm. The precision of analysis for individual natural fluid inclusions ranges from 5 to 31% for both Sr and Rb. The concentration of Sr calculated by this method is in agreement with earlier work.

Paleotemperatures preserved in fluid inclusions in halite

A variety of paleoclimate proxy records allow determination of relative warming or cooling. However, if we are to understand climate change, quantification of past temperature fluctuations is essential. Our research indicates that fluid inclusions in halite can yield homogenization temperatures that record surface brine temperatures at the time of halite precipitation. To avoid problems with stretching, leaking, and initial trapping of air, samples with primary, single-phase (liquid) fluid inclusions are chilled in a freezer to nucleate vapor bubbles. We tested the reliability of this method of obtaining fluid-inclusion homogenization temperatures using modern salts precipitated at Badwater Basin, Death Valley, California. Homogenization temperatures correlate well with measured brine temperatures. The same method is applied to fluid inclusions in Pleistocene halite from a core taken at the same location in Death Valley. Results are at several scales, recording diurnal temperature variations, seasonal temperature fluctuations, and longer-term warming and cooling events that correlate with major changes in the sedimentary environment related to climate. This technique is uniquely instrumental for paleoclimate studies because it offers actual, not just proxy, paleotemperature data.

Stable isotopes of lake and fluid inclusion brines, Dabusun Lake, Qaidam Basin, western China: Hydrology and paleoclimatology in arid environments

The Qaidam Basin, underlain by salt, is the largest (120,000 km2) on the Qinghai-Tibet Plateau, western China. Numerous shallow to ephemeral saline lakes and dry saline pans are present on the Qarhan Salt Plain. Dabusun Lake, the largest (about 200 km2), contains high salinity NaMgCl brines. Whereas it precipitates halite, it is fringed by a potash salt flat. The dominant inflow to Dabusun Lake, the Golmud River, contains dilute Na+HCO−3-rich meteoric waters. Dabusun Lake brines fall on an evaporation trend given by δD(‰) = 3.3δ18O−43. Both δD and δ18O values increase with salinity which in turn varies considerably with flooding and evaporation. The isotope compositions of the fluid inclusion brines from modern halite formed along the lake's edge are intermediate to those of Dabusun Lake brines and those from the salt flat. Shallow sediments beneath Qarhan consist of interbedded salts and mud. A short core section (1.3–1.7 m depth) from the northern edge of Dabusun Lake, was found to contain three dissolution surfaces and three mud partings. The δ18O values for fluid inclusions in 22 primary halite samples from this section show a record of episodic flooding (lower δ18O values) followed by evaporation (gradual increase in δ18O values). Primary fluid inclusions in halite crystallized initially at the surface provide a geochemical record of surface brines. Their major element compositions varied through time. More concentrated fluids indicate more arid conditions in the basin, whereas wetter conditions prevailed during intervals of non-salt deposition when laminated muds accumulated. The isotope compositions together with the activity of H2O of fluid inclusions in primary halite were used to determine isotope variations in regional precipitation and hence paleoclimatic changes on the Qinghai-Tibet Plateau during the past 50,000 years.

Organic inclusions in salt. Part I: Solid and liquid organic matter, carbon dioxide and nitrogen species in fluid inclusions from the Bresse basin (France)

Organic inclusions from the Etrez and Cormoz areas of the Paleogene Bresse salt basin (France) have been studied. Different organic fractions are trapped with brine solutions in fluid inclusions in halite. Isolated inclusions from both areas are brine-bearing, and organic matter is sometimes associated with daughter mineral phases (carbonate, sulfate, clay). Structured and unstructured solid organic matter is observed both in the Etrez area (central basin) and in the Cormoz area (Northern ridge), while liquid organic droplets are only observed in fluid inclusions from the Cormoz area. FTIR microspectroscopic measurements show a low aliphatic contribution, and the presence of aromatic and oxygen double bonds for the solid organic matter. Low to high aliphatic contents (C5 and C7+, deduced from CH 2 CH 3 ratio measurements), low to high CC and CO contributions, and the presence of characteristic CN functions of amino-acids are detected in liquid droplets by FTIR spectroscopy. Carbon dioxide, originating from the thermal degradation of solid organic matter, is generally detected. Organic two-phase inclusions (brine + liquid organic matter) in planes are located in clear halite crystals from the Cormoz area. High aliphatic contributions, and variable aromatic and oxygen contents are observed. Ammonium ions (NH 4 +) are detected in the brine solution, and no carbon dioxide contribution is recorded. Organic matter trapped in the halite of the Bresse basin is immature to early mature. In the deeper part of the basin (Etrez, 800–1000 m), the organic matter in the inclusions is slightly thermally degraded, with little or no generation of liquid organic compounds. This agrees with the data on organic matter previously published from this area. In the Northern ridge (Cormoz, 500–800 m), liquid heteroatomic compounds (C, H, O, N) were produced, migrated through the salt and were trapped without gas phases. This implies a slightly lower temperature in the deeper part (Etrez) of the Bresse basin. Differences in thermal gradients between the Northern ridge, and the deeper part of the Bresse basin, must be invoked to explain differences in organic matter maturation. The analysis of organic inclusions is a contribution to understanding the thermal and biochemical history of the Bresse basin by the in situ observation of organic evolution products which are preserved by entrapment in salt.

Microanalysis of primary fluid inclusions in halite: constraints for an evaporitic sedimentation modeling. Application to the Mulhouse Basin (France)

The chemistry of the waters from which the evaporitic minerals crystallized in the lower part of the Salt IV unit of the Mulhouse Basin (France) has been investigated. The lithological and fluid inclusion data have been compared to the output data of the mass transfer program NEWEQUI which simulates the change in brine composition during its evaporation advancement. The results show that the evolution of the composition of the brine is compatible with the calculated sequence of evaporation of a parent water corresponding to a seawater modified by CaCl 2-rich hydrothermal water. In the studied sequence fluid inclusion data provide useful constraints for reconstructing the paleoenvironment controlling the evaporitic sedimentation. They also provide data on the water stratification in the basin and on its connectivity with the open sea, and important parameters controlling the productivity (possible sources for the nutrients) and the preservation of organic matter in the sediment.

Marine to nonmarine facies transition in Permian evaporites of the Palo Duro Basin, Texas: Geochemical response

The late Paleozoic Palo Duro Basin evolved from a marine to nonmarine environment as it was infilled. The evaporitic part of the sequence (Leonardian through Ochoan) is composed of regressive carbonate-anhydrite-halite cycles that displaced open-marine environments toward the south during basin filling. Systematic vertical changes in evaporite geochemistry through the evaporite section include increasing 87Sr/86Sr ratios and decreasing (altered from marine) δ34S in anhydrite, decreasing (recycled) bromide content of the halite, and increasing meteoric influence on the stable isotopic composition of fluid inclusions in halite. Geochemical changes correspond to changes in evaporite sedimentology and document the evolution from marine-dominated to partly nonmarine evaporites. Geochemical tracers, when used with sedimentological and facies analysis, provide reliable indicators of the sources of water and solutes in an anhydrite- halite facies tract. Perennial, intermittently stratified, and ephemeral brine- pool conditions affect the amount of synsedimentary recycling. Variable rates of reflux and marine recharge control residence times of brines in the depositional environment. These are two key processes in relating evaporite geochemistry to depositional environment.

Determination of carbon and oxygen in fluid inclusions of rocksalt

Nuclear microprobe analysis is used to quantitatively characterize fluid inclusions in halite. We show the presence of three types of fluid inclusions located near the surface of rocksalt sections: hydrocarbon, brine + hydrocarbon and brine-rich inclusions. The elemental salt and and inclusion stability has been verified under microbeam investigation with a beam current density up to 26 pA/smm 2. Oxygen and carbon detection limits of 10 −4 molcm −3 were achieved. Moreover, the composition of these fluid inclusions appears to be strongly inhomogeneous.

Single fluid inclusion analysis by laser ablation inductively coupled plasma atomic emission spectrometry: quantification and validation

Laser ablation inductively coupled plasma atomic emission spectrometry (ICP-AES) can provide quantitative determinations of element ratios in the concentrated brines contained within single fluid inclusions, larger than 30 µm in diameter, in topaz and halite. Inclusions formed at different stages can therefore be analysed separately and differentiated. This is an advantage over previous bulk methods of fluid inclusion analysis by ICP-AES that only provide composite analyses of all inclusion types present. Validation of the laser ablation ICP-AES analyses of the inclusions in topaz was obtained using scanning electron microscopy (qualitative), bulk crush–leach ICP-AES (semiquantitative) and a method of ‘geological feasibility’(semi-quantitative). Quantitative validation was achieved using synchrotron X-ray fluorescence microprobe analysis, which showed no significant bias for the determinations of the ratios between Cu, Fe, Mn, Pb and Zn. Synthetic fluid inclusions containing standard solutions were used to validate the laser ablation ICP-AES analysis of inclusions in halite. A bias of <6% was detected for the determinations of ratios between Ba, Ca, K, Li and Mg, and <20% for Sr:Ca. The precision of individual elemental ratios was 20–45%(relative standard deviation) but this could be reduced to 3–8%(standard error on the mean) by the analysis of large numbers of inclusions (e.g., 30). In some natural inclusions the geochemical variability was found to be a limiting factor in the precision of the replicate measurements. The nebulization of standard solutions was found to be an appropriate method of calibration for the determination of element ratios in this application.

Measurement of the hydrogen and oxygen isotopic compositions of concentrated chloride brines and brines from fluid inclusions in halite

Solutions of 1–5 m NaCl, KCl, CaCl 2 and MgCl 2, and synthetic brines were analyzed for hydrogen and oxygen isotopic compositions by vacuum distillation-microequilibration techniques. No effect on the hydrogen isotopic composition was observed for any of the solutions within the precision of the technique of ±5‰ determined from analyses of distilled water. Oxygen isotopic compositions of solutions measured by vacuum distillation-microequilibration indicate that oxygen isotopes are not fractionated during analysis in NaCl, KCl and CaCl 2 solutions. Vacuum distillation-microequilibration analyses of MgCl 2 solutions show depletions in 18O relative to pure water that can be related to the concentration of Mg 2+ in the solution. The greatest depletion in 18O occurs in the 4 m MgCl 2 solutions which have δ 18O-vaIues 6‰ lower than that measured for pure water. Corrections based on the measurement of the δ 18O-values of the pure MgCl 2 solutions can also be applied to mixed chloride brines. Both melting and crushing of halite grown in solutions of known isotopic composition followed by microequilibration to determine the stable isotopic composition of fluid inclusions give results within the precision determined from analyses of distilled water.

Measurement of the hydrogen and oxygen isotopic compositions of concentrated chloride brines and brines from fluid inclusions in halite

Solutions of 1–5 m NaCl, KCl, CaCl 2 and MgCl 2, and synthetic brines were analyzed for hydrogen and oxygen isotopic compositions by vacuum distillation-microequilibration techniques. No effect on the hydrogen isotopic composition was observed for any of the solutions within the precision of the technique of ±5‰ determined from analyses of distilled water. Oxygen isotopic compositions of solutions measured by vacuum distillation-microequilibration indicate that oxygen isotopes are not fractionated during analysis in NaCl, KCl and CaCl 2 solutions. Vacuum distillation-microequilibration analyses of MgCl 2 solutions show depletions in 18O relative to pure water that can be related to the concentration of Mg 2+ in the solution. The greatest depletion in 18O occurs in the 4 m MgCl 2 solutions which have δ 18O-values 6‰ lower than that measured for pure water. Corrections based on the measurement of the δ 18O-values of the pure MgCl 2 solutions can also be applied to mixed chloride brines. Both melting and crushing of halite grown in solutions of known isotopic composition followed by microequilibration to determine the stable isotopic composition of fluid inclusions give results within the precision determined from analyses of distilled water.

The composition of Permian seawater

Forty-nine brine inclusions in marine halite from the Ochoan Salado Formation in the Delaware Basin and fifteen inclusions in halite from the Leonardian Wellington Formation in the Kansas Basin were extracted, and their chemical compositions were determined. The brines are of the Na-K-Mg-Cl-SO 4 type; their compositions resemble those of evaporated modern seawater. The values of (m Cl − − m Na + ) m Br − and (m Mg 2+ + m Ca 2+ − m SO 4 2− − 1 2 m m HCO 3 − ) m Br − of the inclusion brine from the two formations are equal to or slightly higher than those of modern seawater. The original m Na + m Br − and m Cl − M br − ratios of the inclusion brines were probably equal to or slightly larger than those of modern seawater. The values of m Mg 2+ m Br − of the inclusion brines from the Salado Formation are very close to that of modern seawater; the ratios of inclusion brines from the Wellington Formation are slightly lower, probably due to the formation of dolomite/magnesite. The m Mg 2+ m Br − ratio in the initial seawater was probably close to the parent seawater of the Salado brines. The values of (m SO 4 2− − m Ca 2+ + 1 2 m HCO 3 − ) m Br − of the inclusion brines appear to be reduced by the formation of dolomite/magnesite, and the value of this ratio in Permian seawater was probably similar to that of modern seawater. The m K + M br − ratios of the inclusion brines are variable, but the original ratios are probably close to or slightly larger than that of modern seawater. If the Br − concentration of Permian seawater was equal to that of modern seawater, the composition of Permian seawater can be narrowly constrained; in mmol/kg H 2O, 460 ≤ m Na + < 630, 550 ≤ m Cl − < 730, m Mg 2+ = 54 ± 6, m K + ∼- 11, ( mSO 2− 4 − m Ca 2+ + 1 2 m m HCO 3 − ) ≥ 17, 20 < m SO 4 2− < 45, 5 < m Ca 2+ < 20, and 0.15 < m Hco 3 − < 5 . The composition of Permian seawater was therefore quite similar to that of modern seawater.

Stable isotope paleoclimatology of brine inclusions in halite: Modeling and application to Searles Lake, California

The isotopic composition of brine inclusions in halite can be used as paleohydrologic and paleoclimatic indicators in arid environments. For this purpose, steady-state isotopic models of the brine inclusions in halite were developed for three hydrologic regimes: the “evaporation pan,” “terminal-lake,” and “through-flow lake” or “strait-exchange sea.” The model calculations predict that the steady-state isotopic compositions are sensitive to the hydrologic regime, to the normalized relative humidity, and to the isotopic compositions of atmospheric water vapor and inflow water. Short-term fluctuations of the isotopic parameters in the steady-state equations are not important, and in general only the long-term mean values are recorded in the brine inclusions in halite. Modern and old (up to 1.95 Ma) samples of nonmarine halite from Searles Lake (California) were analyzed for the chemical and isotopic compositions of the brine inclusions. From the modern surface halite, the isotopic composition of the atmospheric water (probably of the winter time) and the probable seasons when the halite samples were deposited were obtained. From brine inclusions of the 1.3 Ma halite, the annual-mean isotopic compositions of atmospheric water vapor and inflow water were calculated using the steady-state “terminal lake” model. The calculated isotopic composition of the 1.3 Ma inflow water shows a δD enrichment of about 60%. compared to the modern counterpart. The amount of this δD enrichment is similar to that found from the calcite veins at the Spring Mountain in Nevada ( Wionograd et al., 1985), which was attributed to the effect of the orogeny of the Sierra Nevada. The chemical composition of the brine inclusions indicates that the Owens River was more enriched in HCO 3 −(+CO 3 2−) 10,000 and 28,000 a ago than at present, probably due to larger contribution of Long Valley caldera hot spring waters.

Chemistry of fluid inclusions in halite from the Salina Group of the Michigan basin: Implications for Late Silurian seawater and the origin of sedimentary brines

Fluid was extracted from 18 fluid inclusions in halite of the Late Silurian Salina Group exposed in the Crystal Mine on the outskirts of Detroit, Michigan. Compared with modern seawater evaporated to the same degree, the inclusion fluids are severely depleted in SO 4 −2, somewhat depleted in Na + and Mg +2, and greatly enriched in Ca +2. The composition of the inclusion fluids can be derived from Silurian seawater with a composition close to that of modern seawater, if it is assumed that the composition of the Silurian seawater was modified by dolomitizing CaCO 3-rich sediments and by albitizing silicate minerals during its evolution into evaporite brines. Since the evolution of the brines involved a number of chemical reactions, it is impossible to recover the initial concentration of all of the major ions in the parent Silurian seawater from the composition of the inclusion fluids alone. It is likely, however, that the m k + m Br − ratio and the functions [m Ca +2 + m Mg +2 − m SO 4 −2 − m HCO 3 − 2m Br − and [if m cl − − m Na + m Br − ] in Late Silurian seawater had values close to those of modern seawater. Measurements of the isotopic composition of sulfur and of Sr in anhydrite within and associated with the halite host of the fluid inclusions are consistent with previous measurements of δ 34 S in Silurian marine anhydrites and with the 87Sr 86Sr ratios of Late Silurian marine carbonates.

Geochemical investigation of NaCl-KCl-MgCl2-CaCl2-FeCl2 solutions in Zechstein 2 salt, Suldrup Dome, Denmark. Microthermometry on fluid inclusions in halite

Large, irregular fluid inclusions with daughter bischofite, MgCl2 • 6H2O, in recrystallized halite from former brine pockets in grey Zechstein 2 rock salt from the Suldrup dome, Denmark, were studied by means of microthermometry. The test material consists of ca 3 kg cleavage pieces and a piece of core of extremely clean, colourles, limpid halite. Anhydrite and pyrrhotite are present as solid inclusions in trace amounts only. The irregular inclusions studied all contain daughter bischofite at room temperature. Optical, crystallographic, and chemical (melting) methods proved the daughter mineral to be bischofite. The mean dissolving temperature Tmhex = 56.5 ± 0.9°C, 95% confidence limit, of 117 measurements yields, from pertinent phase diagrams, a quantitative composition of the equilibrium solution: 114 mol MgCl2 + 1.2 mol K2Cl2 per 1000 mol H2O, saturated with NaCl (ca. 2 mol Na2Cl2 per 100 mol H2O). Exposed to the atmosphere, the equilibrium solution becomes orange yellowish after some days, thus proving the presence of FeCl2 (5-10 mol/1000 mol H2O). In one inclusion carnallite (KMgCl3 • 6H2O) was observed, the dissolving temperature Tmcar = 81.9°C of which is a minimum trapping temperature. The minimum trapping pressure is calculated at slightly higher than 65 MPa. The viscosity at 80°C is estimated at ca. 4 centipoise. Measurements of the homogenization temperature in fluid phase are meaningless due to the presence of compressed gas, possibly H2S. The following model is proposed concerning the formation of the studied halite: During the end of the diapiric penetration phase in Lower Cretaceous, a metamorphic lye mixed with concentrated sea water in NaCl facies in brine pockets within the grey Zechstein 2 rock salt, causing salting out of the studied halite. The metamorphic lye derived from a metamorphosed carnallitic potash zone. The carnallitic solution was mixed with an infiltrating rinneitic (3KC1 · NaCl · FeCl2) solution. The mixture was squeezed out from the potash zone during the diapiric penetration phase, leaving a trail of disseminated grains and fracture fillings of carnallite all the way up to the former brine pockets. The minerals bischofite and pyrrhotite, Fe1-xS, are reported from Denmark for the first time.

Effect of partially dissolved impurity on the mobility of liquid inclusions in halite

Effect of partially dissolved impurity on the mobility of liquid inclusions in halite

The analysis of fluid inclusions in halite

A technique has been developed to drill into fluid inclusions in halite, to extract the inclusion fluids, and to determine the concentration of all of the major and some of the minor constituents in these fluids. The minimum diameter of usable fluid inclusions is ca. 250 μm. After dilution, the fluids are analyzed by ion chromatography and coulometry. Uncertainties in the concentration of the major cations and anions is on the order of 4%. The analytical scheme provides much more precise analyses of inclusion fluids than have been available to date. The analyses are a useful starting point for reconstructing the composition of the seawater from which the evaporite brines evolved.

H 2S-bearing inclusions in recrystallized halite

On a cryogenic investigation solid H 2S was successively observed after freezing CO 2 in water-poor fluid inclusions in halite of Cambrian Siberian salts. Melting of a H 2S solid phase occurs at nearly eutectic temperatures of −95.6°C in CO 2H 2S inclusions and in the range −98° to −100°C in CO 2H 2SCH 4 or CO 2H 2SN 2 inclusions. The compositions of the inclusions were determined by Raman microspectrometry.

Extraction and isotopic analysis of fluid inclusions in halites.

Basic technique for the extraction and isotopic analysis of fluid inclusions in halite was investigated using synthetic single crystals of halite and three natural halite samples from China. Vacuum ball-mill, vacuum decrepitation and vacuum melting methods were examined for the extraction of fluid inclusions. Results of analyses on δD and δ18O of the water in fluid inclusions extracted by the ball-mill method from synthetic single crystals agreed with those of the mother solution from which the single crystals were formed. Although the δ18O value of the water extracted by the melting method agrees well with that of the mother solution, the δD value was about 7‰ more negative than that of the mother solution. There was a great difference in both δD and δ18O of the water extracted by the two methods applied to the identical natural halite samples; the melting method gave consistently more negative values for both δD and δ18O compared with those by the ball-mill method. The difference was interpreted as a result of the hydrolysis of NaCI with H2O combined with the formation of oxides of alkaline-earth elements in brine inclusions in natural halite samples in the process of the melting method. Although the melting method has an advantage of complete recovery of volatiles in halite samples, the chemical and isotopic compositions of volatiles can not be retained owing to a variety of thermal reactions which occur at high temperatures. It was concluded that the ball-mill method is much superior to the melting method in order to obtain isotopic and chemical information on fluid inclusions in halite, though the recovery of fluid inclusions by the ball-mill method is not 100%, and high concentrations of Mg2+ and Ca2+ in fluid inclusions require correction for the δD and δ18O values of the water.

Zechstein Salt Denmark. Salt Research Project EFP-81. Volume IV: Microthermometry

Volume IV is part of four volumes elaborated in the course of Salt Research Project EFP-81. The volume deals with studies of fluid inclusions in halite and quartz crystals from Danish salt dornes.