Mineralogical Profiles Research Articles

Bay Laurel of Northern Morocco: A Comprehensive Analysis of Its Phytochemical Profile, Mineralogical Composition, and Antioxidant Potential

Laurus nobilis, sometimes referred to as laurel, has been used for medicinal and culinary purposes for a very long time. The main subjects of this study are the phytochemical composition, mineralogical profile, and potential antioxidant properties of Laurus nobilis in Tangier, Northern Morocco. For phytochemical analysis of methanolic extracts, high-performance liquid chromatography (HPLC-UV-MS) was used, and Fourier transformation infrared spectroscopy (FT-IR) was used to identify each individual component. Minerals were studied by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and wavelength dispersive X-ray fluorescence (WD-XRF). Total tannin, flavonoid, and phenolic amounts were quantified using aqueous and methanolic extracts. The antioxidant properties were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) assays. Research has revealed a complex array of phytochemicals, including tannins, flavonoids, and phenolic acids. Mineral analysis has revealed the existence of vital components that are beneficial to health. Comparing the methanolic extract to the water extract, it demonstrated higher levels of phenols, flavonoids, and tannins as well as stronger antioxidant activity, indicating greater health benefits. This comprehensive study highlights the importance of Laurus nobilis from Northern Morocco as a reliable botanic resource with potential pharmaceutical, nutritional, and cosmetic uses.

The utility of dust for forensic intelligence: Exploring collection methods and detection limits for environmental DNA, elemental and mineralogical analyses of dust samples

Environmental DNA (eDNA), elemental and mineralogical analyses of soil have been shown to be specific to their source material, prompting consideration of using the airborne fraction of soil (dust) for forensic intelligence work. Dust is ubiquitous in the environment and is easily transferred to items belonging to a person of interest, making dust analysis an ideal tool in forensic casework. The advent of Massive Parallel Sequencing technologies means metabarcoding of eDNA can uncover bacterial, fungal, and even plant genetic fingerprints in dust particles. Combining this with elemental and mineralogical compositions offers multiple, complementary lines of evidence for tracing the origin of an unknown dust sample. This is particularly pertinent when recovering dust from a person of interest to ascertain where they may have travelled. Prior to proposing dust as a forensic trace material, however, the optimum sampling protocols and detection limits need to be established to place parameters around its utility in this context. We tested several approaches to collecting dust from different materials and determined the lowest quantity of dust that could be analysed for eDNA, elemental composition and mineralogy, whilst still yielding results capable of distinguishing between sites. We found that fungal eDNA profiles could be obtained from multiple sample types and that tape lifts were the optimum collection method for discriminating between sites. We successfully recovered both fungal and bacterial eDNA profiles down to 3 mg of dust (the lowest tested quantity) and recovered elemental and mineralogical compositions for all tested sample quantities. We show that dust can be reliably recovered from different sample types, using different sampling techniques, and that fungi and bacteria, as well as elemental and mineralogical profiles, can be generated from small sample quantities, highlighting the utility of dust for forensic intelligence.

Appraisal of hydrochemistry and suitability assessment for water in an agriculture-dominated aquatic ecosystem of Rajasthan, India

The study is the first comprehensive investigation of the water quality and geochemistry of an ecologically important large endorheic lake located in Rajasthan, India. The water quality and its suitability appraisal classified the water as fit for drinking, irrigation, and industrial application with the possible problem of corrosion. Most of the dissolved ions were observed to be coming from crustal/natural origin, with the exception of chloride. The water was observed to be MgHCO3 type and CaMgCl type based on the relative abundance of ions. Considering the environmental relevance towards eutrophication, the Nitrogen:Phosphorous (N:P) value of 10:1 in water classified the lake in transition from oligotrophic to eutrophic with an urgent need of intervention to arrest addition of domestic wastewater and agricultural runoff. Additionally, Fourier Transmission Infra-Red (FTIR) investigation of sediments and soil revealed that the chemical signatures of soil and sediments are similar, and most of the sediments are transported into the lake from a short distance. The geochemical classification of water and mineralogical profile of soil and sediments of the lake confirmed that rock–water interaction (silicate weathering in particular) is controlling the water chemistry via direct cation exchange. Considering the importance of lake as a hotspot for tourists, migratory birds, crocodile conservation, aquaculture and its application for irrigation and drinking, present study recommends effective management of water quality for its sustainable use.Graphical abstract

Phasing the history of ancient buildings through PCA on mortars’ mineralogical profiles: the example of the Sarno Baths (Pompeii)

AbstractA total of 83 wall joint mortar samples collected from the Sarno Baths complex in Pompeii (Naples, Italy) were analysed by optical microscopy (OM) and X‐ray powder diffraction‐quantitative phase analysis (XRPD‐QPA) in order to scan the ancient construction phases and modern restorations to which the building was subject. The major issue to overcome in the research depended on the fact that the most part of the analysed mortars was taken from undated structures, while only 35 were collected from dated ones. In order to observe correlations in sample distribution which could reflect ancient building phases and modern restorations, we then processed XRPD‐QPA data of the mortars through principal component analysis (PCA). A rational subdivision of the full dataset into a smaller one before performing PCA was a useful step for a proper enucleation of coherent groups. The presence in most of the resulting groups of dated samples also allowed us to place in a precise timeframe the undated ones. This study demonstrates that our approach, integrating the traditional archaeological analysis with archaeometrical methods and statistics, could be adopted as a tool with which to frame the constructive episodes in other ancient buildings in Pompeii as well as at other archaeological sites.

Bryozoan carbonate skeletal geochemical composition in the White Sea compared with neighbouring seas

A fundamental question underlying skeletal mineral secretion in marine invertebrates is the extent to which the physico-chemical parameters of seawater (e.g., salinity, temperature) and animal physiology influence their skeletal mineralogy and chemistry. Groups with more complex mineralogies, such as bryozoans, have the ability to actively control their own skeletal composition in response to environmental conditions and could be considered indicators of global environmental change. Thus, this study aims to reveal how the unique environmental conditions of low salinity (circa 24–26), prominent seasonality and semi-isolation of the White Sea (WS) subarctic region caused by the last glaciation (12,000 ya) affect the carbonate skeletal geochemical composition of bryozoans. X-ray diffraction analysis of 27 bryozoan taxa (92 specimens) revealed a completely monomineral calcite composition of skeletons with a mean value of 6.9 ± 1.8 mol% MgCO3 and moderate variability at the species and family levels. Most specimens (43.5%) precipitated skeletal magnesium within the range of 7–8 mol% MgCO3. Regional analysis of the mineralogical profile of the White Sea bryozoans shows that they differ statistically from bryozoan species living in the neighbouring Arctic and temperate Scotland regions in terms of magnesium content in calcite (approximately 7 mol% MgCO3 in the White Sea versus 5 mol% MgCO3 in other regions). We suggest that the effect of low salinity on magnesium content was compensated by relatively high summer temperature causing rapid growth and calcification and possibly resulted in the increased Mg contents in the White Sea (WS) bryozoans. However, on a local scale (between sampling locations), the influence of temperature and salinity could be excluded as a source of observed intraspecific variability. The concentration of MgCO3 in skeletons of the studied bryozoans is controlled by other environmental variables or is species-specific and depends on the physiological processes of the organisms.

An unusual occurrence of ferroan magnesite in a tonstein from the Minusinsk Basin in Siberia, Russia

Altered volcanic ash layers are common constituents of coal beds throughout the world and are typically preserved as thinly bedded, kaolinite-rich layers called tonsteins. Two tonsteins from the Minusinsk coal basin in southern Siberia, Russia, were selected for bulk chemistry analysis and the lower tonstein was selected for analysis by X-ray diffraction (XRD) and scanning electron microscopy with an energy dispersive detector (SEM/EDS). In addition to minerals commonly found in tonsteins such as kaolinite, K-feldspar, quartz, apatite, zircon, and sulfide minerals, the mineralogical profile of this tonstein includes a unique groundmass component of ferroan magnesite, confirmed by XRD. Ferroan magnesite has never before been reported in tonsteins and has been only briefly mentioned in one paper as a rare mineral found in freshwater sediments associated with coal. The probable parent magma type of the ash was evaluated using TiO2/Al2O3 and Zr/TiO2 vs. Nb/Y classification plots as well as chondrite-normalized REE distribution profiles. The results indicate a probable magmatic source of rhyolitic to slightly andesitic composition. The magnesium source is enigmatic: felsic to intermediate magmas are typically Mg-poor. Furthermore, a Mg-rich environment during initial clay mineral formation would typically result in a smectite or illite clay mineral assemblage instead of the dominant kaolinite present. Several potential external sources of Mg for ferroan magnesite formation were examined, including marine incursion, hydrothermal activity, and influx of non-marine Mg-rich porewaters. Low total sulfur content and absence of illite make marine incursion improbable, and there is no evidence of hydrothermal influence. Total MgO levels fall well within expected limits for a felsic magmatic source, so there is no clear indication of a large influx of Mg into the system post-depositionally. The most likely explanation of this unusual occurrence of ferroan magnesite is that magnesium and iron-bearing minerals in the volcanic ash and underlying rock layers were dissolved and mobilized by HCO3-bearing solutions from organic material in the peat swamp, which in turn allowed ferroan magnesite to precipitate in the subsurface during diagenesis.

Mineralogical Profile of Supergene Sulfide Ore in the Western Copper Area, Morenci Mine, Arizona

Mineralogical Profile of Supergene Sulfide Ore in the Western Copper Area, Morenci Mine, Arizona

Mineralogical Diversity in Lake Pavin: Connections with Water Column Chemistry and Biomineralization Processes

As biominerals are good tracers of microbial interactions with the environment, they may provide signatures of microbial evolution and paleoenvironmental conditions. Since modern analogues of past environments help with defining proxies and biosignatures, we explored microbe mineral interactions in the water column of a maar lake, located in France: Lake Pavin. This lake is considered as a potential Precambrian ocean analogue, as it is ferruginous and meromictic, i.e., stratified with a superficial O2-rich layer (mixolimnion) and a deeper permanently anoxic layer (monimolimnion). We combined bulk chemical analyses of dissolved and particulate matter in combination with electron microscopy analyses of the particulate matter at different depths along the water column. The mineralogy changed along with water chemistry, and most of the minerals were intimately associated with microorganisms. Evolution of the redox conditions with depth leads to the successive precipitation of silica and carbonates, Mn-bearing, Fe-bearing and S-containing phases, with a predominance of phosphates in the monimolimnion. This scheme parallels the currently-assessed changes of microbial diversity with depth. The present results corroborate previous studies that suggested a strong influence of microbial activity on mineralogical diversity through extracellular and intracellular biomineralization. This paper reports detailed data on mineralogical profiles of the water column and encourages extended investigation of these processes.

Mineralogy of soils on the Baer mounds in southern Astrakhan oblast

The methods of X-ray diffractometry, scanning electron microscopy, and energy dispersion analysis have been used in the mineralogical study of Baer mound soils in the southern part of the Astrakhan oblast. It has been established that such framework minerals as quartz and feldspars form the basis of the mineralogical composition of soils and mound deposits. It has been shown that the mound topsoils have similar mineralogy along the entire profile. Besides the essentially higher content of layered minerals, the soils at the foot of the mound and in the intermound hollow are characterized by a binomial mineralogical profile. Kaolin, chlorite, illite, illite-smectite, and smectite have been identified in the clay fraction of the soils. The processes of illitization growing down the slope and along the soil profile have been recognized in the soils.

Using the chemical composition of carbonate rocks on Mars as a record of secondary interaction with liquid water

In the search for habitable environments on Mars, sites that have been altered by liquid water represent an important target. Quickly dissolving and precipitating carbonates, found in multiple locations on Mars, represent a key potential mineral indicator of locations with a history of aqueous alteration, and therefore possible habitability. Recent liquid surface water on Mars may differ significantly from the fluids, either sedimentary, hydrothermal, or pedogenic, that formed carbonate minerals on Mars. Interactions of carbonate rocks with such recent surface water may therefore cause changes in chemistry and mineralogy with depth that form weathering profiles recording the conditions of alteration. To test the prediction that martian carbonates may record a signature of aqueous alteration on Mars, we performed reactive transport modeling of putative carbonate outcrops on Mars using the reactive transport code CrunchFlow. Model inputs included two parent rocks chosen based on the carbonate-rich rock at Gusev Crater, Comanche, one consisting of 60% magnesite, 20% siderite, and 20% porosity, and one consisting of 50% magnesite, 20% siderite, 9% calcite, 1.6% rhodochrosite, and ~20% porosity. Reacting solutions consisted of four scenarios: acidic, sulfate-containing solutions, perhaps resulting from an acid vapor scenario; dilute solutions resulting from martian analog basalt dissolution; concentrated solutions resulting from modeled evaporation of the dilute solutions; and solutions based on the results of the Phoenix Lander. Modeling was performed under low oxidation and high oxidation conditions. Based on the modeling results, a carbonate rock would become enriched in siderite upon interaction with acidic water under low oxidation conditions; the same rock would become enriched in calcite after interaction with Ca-enriched solutions. A carbonate rock reacting under more oxidizing conditions would preferentially dissolve siderite, leaving a surface enriched in magnesite and ferric oxide. Therefore, the Mg-rich carbonates on Mars are consistent with possible interaction with liquid water under oxidizing conditions, similar to those measured at the Phoenix landing site. Future detailed chemical and mineralogical profiles through weathered rock into the unaltered interior of carbonate rocks may therefore allow the quantitative interpretation of the aqueous history and possible habitability of locations on Mars.

In situ investigations and reactive transport modelling of cement paste/argillite interactions in a saturated context and outside an excavated disturbed zone

The interactions between cementitious materials and a clayey deep formation were investigated by studying the specific in situ context of the Tournemire Underground Research Laboratory (URL) of the French Institute for Radioprotection and Nuclear Safety and by reactive transport modelling using the HYTEC code. The study forms part of the safety assessment framework for the deep geological disposal of high to intermediate level long-lived radioactive waste. The in situ context investigated in the Tournemire URL corresponds to an engineered cemented borehole crosscutting the Toarcian argillite formation. The argillite/CEM II cement paste contacts have been in place over 18a and were sampled in a saturated context outside the excavated disturbed zone (EDZ). Studies of the mineralogy (XRD, carbonatometry, SEM and TEM), petrophysical properties (BET) and geochemistry (TOC, Sr contents, C, O and Sr isotopes, EDS analyses) were carried out both on the argillite and on the cement paste in contact. Alteration of the cement paste is clearly expressed by decalcification and the opening of macroporosity. These modifications are mainly due to the dissolution of portlandite. The neoformation of C–S–H phases was identified in the first few micrometre next to the argillite interface, along with secondary carbonates at the outermost contact. Geochemical measurements argue for the introduction of a sedimentary fluid into the macroporosity of the cement paste to explain the formation of part of these secondary phases. This hypothesis is considered and tested using the HYTEC code, which indicates that such transport could have occurred near the argillite/cement paste contact at a very early stage. After this stage, the transport was reversed and ‘cementitious’ fluids flowed from the cement paste to the argillite. The changes brought about by these fluids are observed over a thickness of 11–13mm in a so-called ‘black rim’, in which carbonates and C–S–H secondary phases are identified in the matrix of the sediment. An illitization process may also be observed in this altered rim, reaching its maximum development towards the inner part. Geochemical analyses show that the argillite disturbances are strictly confined to the black rim. Theoretical mineralogical profiles based on thermodynamic equilibria defined by the HYTEC code are in good agreement with the observations, and are used to achieve a better understanding of transport processes.

The impact of cemented layers and hardpans on oxygen diffusivity in mining waste heaps A field study of the Halsbrücke lead–zinc mine tailings (Germany)

This article reports fibre-optic oxygen measurements on a reactive mine waste heap located in the polymetallic sulphide mine district of Freiberg in south-eastern Germany. The heaped material consists of sulphide-bearing tailings from a processing plant of a lead–zinc mine. Mine waste material was deposited in the water phase after separation of mining ores in a flotation process. The tailing impoundment is partly covered with coarse sand and topsoil. Oxygen profiles were monitored during one year at eleven locations showing different physical and mineralogical compositions. At each location a borehole was drilled where the optic sensors were installed at 2–5 different depths. After installation the oxygen profiles were monitored seven times during one year from 2006–2007 and three to five oxygen profiles at each location were obtained. Oxygen measurements were accompanied by physical, chemical and mineralogical data of the tailing material. Additionally, a detailed mineralogical profile was analysed at a location representative for the central part of the heap, where the cemented layers show lateral continuity. Results showed that cemented layers have a significant influence on natural attenuation of the toxic As and Pb species owing to their capacity of water retention. The measured oxygen profiles are controlled by the zone of active pyrite weathering as well as by the higher water content in the cemented layers which reduces gaseous atmospheric oxygen supply. In contrast, gypsum bearing hardpans detected at three other locations have no detectable influence on oxygen profiles. Furthermore, the grain size distribution was proved to have a major effect on oxygen diffusivity due to its control on the water saturation. Temporal changes of the oxygen profiles were only observed at locations with coarse sediment material indicating also an important advective part of gas flux.

Modelling chemical depletion profiles in regolith

Chemical or mineralogical profiles in regolith display reaction fronts that document depletion of leachable elements or minerals. A generalized equation employing lumped parameters was derived to model such ubiquitously observed patterns: C = C 0 C 0 − C x = 0 C x = 0 exp ( Γ ini · k ˆ · x ) + 1 Here C, C x = 0 , and C o are the concentrations of an element at a given depth x, at the top of the reaction front, or in parent respectively. Γ ini is the roughness of the dissolving mineral in the parent and k̂ˆ is a lumped kinetic parameter. This kinetic parameter is an inverse function of the porefluid advective velocity and a direct function of the dissolution rate constant times mineral surface area per unit volume regolith. This model equation fits profiles of concentration versus depth for albite in seven weathering systems and is consistent with the interpretation that the surface area (m 2 mineral m − 3 bulk regolith) varies linearly with the concentration of the dissolving mineral across the front. Dissolution rate constants can be calculated from the lumped fit parameters for these profiles using observed values of weathering advance rate, the proton driving force, the geometric surface area per unit volume regolith and parent concentration of albite. These calculated values of the dissolution rate constant compare favorably to literature values. The model equation, useful for reaction fronts in both steady-state erosional and quasi-stationary non-erosional systems, incorporates the variation of reaction affinity using pH as a master variable. Use of this model equation to fit depletion fronts for soils highlights the importance of buffering of pH in the soil system. Furthermore, the equation should allow better understanding of the effects of important environmental variables on weathering rates.

Reactive transport modeling of geochemical interactions at a concrete/argillite interface, Tournemire site (France)

Mineralogical and petrographical investigations of a borehole sealed by concrete (“engineered analogue” of concrete/clay interactions) overcored at the Tournemire site offer the possibility to perform reactive transport modeling over a timescale of 15 years, which is significantly longer than standard durations of laboratory experiments. The HYTEC code was used to simulate mineralogical evolutions in the Tournemire argillite matrix and along small fractures, as well as in concrete, assuming either thermodynamic equilibrium approach or kinetic control coupled to diffusive transfer. The mineralogical profiles calculated in thermodynamic equilibrium and with kinetics are very similar in the concrete. In contrast, kinetics of dissolution and precipitation reactions is found to be necessary for a better reproduction of the experimental observations in the argillite samples compared to thermodynamic equilibrium calculations, in particular with respect to the extent of the alkaline perturbation. The major effects observed when considering kinetics in the calculations are to smooth the sharpness and intensity of the mineralogical transformation fronts, these fronts being predicted to occur deeper inside the argillite matrix (<1 cm) and the fractures (⩽2 cm), as well as to lessen clogging of pores within the argillite. At 15 °C, the secondary mineral sequence simulated from the concrete to the argillite is: CSH/ettringite/carbonates at the concrete/argillite interface, followed by a zone of neoformation of clay-like phases and calcite, and a last zone with precipitation of calcite. Main discrepancies between the modeling results and the experimental observations are the precipitation of muscovite instead of K-feldspar and the neoformation of zeolites. Calculations also correctly predict that carbonates form at the concrete/argillite interface, which most probably result from concrete alteration and follow Ostwald’s step rule of mineral precipitation with a predominance of metastable vaterite over calcite.

In situ mineralogy and permeability logs from downhole measurements: Application to a case study in chlorite‐coated sandstones

Well‐logging techniques provide continuous profiles of various in situ physical properties like the bulk density, the photoelectric effect, and the natural gamma radioactivity of geological formations. Our purpose is to use this information to determine a continuous profile of the mineralogy with depth. The well‐log derived mineralogy is then combined with a petrophysical model to infer continuous permeability and saturation profiles in chlorite‐bearing sandstone formations. Our mineralogical inversion algorithm combines a cluster analysis of the raw data and their inversion using the generalized nonlinear inverse method developed by Tarantola and Valette [1982]. A field case is treated concerning a borehole intersecting an alternation of sandstones and shales. The mineralogical logs we obtained are in very good agreement with the mineral proportions measured independently on core samples. Mineralogical profiles are combined with a specific textural model to derive a continuous profile of permeability. We found a very good agreement between this computed permeability log and independent core permeability measurements over 3 orders of magnitude.

Assessing the Unique Characteristics of Close-Proximity Soil Samples: Just How Useful Is Soil Evidence?

Abstract An evaluation of current techniques used in the forensic analysis of soils and geologic evidence. Research was performed to determine the discriminative qualities of the various procedures to discern at what point soils become indistinguishable from one another. Included in this research is an assessment of the techniques from an analyst standpoint to determine what level of advanced mineralogical examination is required to segregate one sample from another. One hundred samples were collected from three different sites; a beach, an island isolated by a river, and a bus parking lot. The samples were analyzed utilizing color determination, particle size distribution analysis and mineralogical profiles of the twenty-five most common soil minerals. Of the three hundred samples examined, over one-half could be discriminated by color alone, the remainder needing only particle size distributions analysis for differentiation, negating the need for lengthy mineralogical examinations. These examinations were conducted with very inexpensive equipment and calculations which could be used with a minimum of training and cost.

Mineralogical and geochemical profile through the Echassieres Ta-Li-Sn mineralized granite (French Massif Central)

Mineralogical and geochemical profile through the Echassieres Ta-Li-Sn mineralized granite (French Massif Central)

In situ investigations of thermal conductivity, heat production, and past hydrothermal circulation in the Cajon Pass Scientific Drillhole, California

Wireline logs from the Cajon Pass drillhole provide observations of crustal properties and processes near the San Andreas fault. Mineralogical profiles developed from geochemical logs are combined with a technique for calculating thermal conductivity from the volume fractions of component minerals. Variations in the equilibrium temperature gradient correlate with conductivity contrasts, and thus with lithology, rather than with fluid circulation. K, U, and Th contents calculated from gamma spectroscopy logs yield heat production values which range from 1.3 to 2.4 µW/m³, averaging 1.8 µW/m³ in the section from 500 to 1800 m. Evidence for depletion of U relative to Th raises the possibility of extensive fluid circulation in the past. However, discontinuity of depletion across faults suggests that the fluid regime responsible for U depletion predated San Andreas faulting.

Layer-By-Layer Mechanism of Smectite Illitization and Application to a New Rate Law

AbstractA layer-by-layer mechanism explains important features of mixed-layer clay minerals formed during the illitization of smectite, including the occurrence of randomly interstratified illite/smectite, the transition to ordered interstratifications, and the development of long-range ordering. A variety of solid-state transformation mechanisms were tested with a stochastic model, which accounts for interactions among clay layers. The model produces most successful results when the reaction of smectite layers with one illite nearest neighbor is favored over smectites with no illite neighbors by a factor of about two, and over those with two illite neighbors by a factor of ten or more. Synthetic X-ray powder diffraction patterns calculated from model results compare well with those of illite/smectite minerals. These results suggest a new kinetic rate law. Solutions to this rate law for reaction within sediments undergoing burial give mineralogical profiles with depth similar to those observed in subsiding sedimentary basins.