Diamonds containing fluid inclusions provide invaluable samples of upper mantle fluids, the study of which illuminates not only diamond formation but also the long-term evolution of the subcratonic, lithospheric mantle. The very large range of inclusion compositions worldwide has been interpreted to represent four end-member fluids: saline (rich in Na + K + Cl); silicic (rich in Si + Al); and carbonatitic

Methane generated by microorganisms is most often depleted in the doubly substituted isotopologue 12CH2D2 relative to the stochastic reference distribution. To constrain the controls on depleted Δ12CH2D2 values, we experimentally isolated the root cause with microorganisms that produce methane from methylphosphonate via the C-P lyase pathway. This mechanism of methane production preserves the three

The feedback between CO2 sources and sinks through chemical weathering is one of the important reasons why Earth has maintained a habitable climate for over four billion years. The lithium (Li) isotopic system is a promising tracer of silicate weathering, but the mechanisms causing its isotope fractionation during weathering remain ambiguous. Here, we performed batch experiments of Li adsorption to

The westward subduction of the Pacific plate interacted with the northward subduction of the eastern Neo-Tethys plate in the Early Cretaceous. However, the subduction polarities between these two plates in the Early Cretaceous is not well constrained. The proto-Philippine arc is suggested to have originated at the Pacific – Neo-Tethys intersection in the SW Pacific in the latest Jurassic – Early Cretaceous

Coccolithophores are important contributors to global calcium carbonate through their species-specific production of calcite coccoliths. Nannofossil coccolith calcite remains an important tool for paleoreconstructions through geochemical analysis of isotopic and trace element incorporation including Sr, which is a potential indicator of past surface ocean temperature and productivity. Scyphosphaera

In the lower part of the mantle transition zone, seismic polarization anisotropies, which could be caused by the lattice preferred orientation (LPO) of elastically anisotropic minerals, were observed related with subducted materials. Stishovite, which is one of the dominant minerals in mid-ocean ridge basalt, continental crust and sediment layers, possesses significant anisotropic elasticity and has

The dynamo effect is the most popular candidate to explain the non-primordial magnetic fields of astrophysical objects. Although many systematic studies of parameters have already been made to determine the different dynamical regimes explored by direct numerical geodynamo simulations, it is only recently that the regime corresponding to the outer core of the Earth characterized by a balance of forces

Gas diffusion-sorption is a critical step in coalbed methane (CBM) exploitation and carbon dioxide sequestration. Because of the particularity of gas physical properties, it is difficult to visualize the gas diffusion-sorption process in coal by experimental methods. Due to the limitation of experimental approaches to image the three-dimensional coal pore structure, it is impossible to obtain the three-dimensional

Gases present in the Earth crust are important in various branches of human activities. Hydrocarbons are a significant energy resource, helium is applied in many high-tech instruments, and studies of crustal gas dynamics provide insight in the geodynamic processes and help monitor seismic and volcanic hazards. Quantitative analysis of methane and CO2 migration is important for climate change studies

Plugging high-permeability zones within oil reservoirs is a straightforward approach to enhance oil recovery by diverting waterflooding fluids through the lower-permeability oil-saturated zones and thereby increase hydrocarbon displacement by improvements in sweep efficiency. Sporosarcina pasteurii (ATCC 11859) is a nitrogen-circulating bacterium capable of precipitating calcium carbonate given a calcium

This study aims to better understand, at a regional scale, the concentration and distribution of selected chemical elements in surface environments and the influence of natural factors (geological background, geomorphology) and anthropogenic factors (mining activities, land-use, agricultural fertilization) on their distribution in the Baoshan area, Yunnan province, southwest China. Mineral resources

Analyses of Lunar Laser Ranging data show that the spin‐symmetry axis of the Moon is ahead of its expected Cassini state by an angle of 𝜙p = 0.27 arcsec. This indicates the presence of one or more dissipation mechanisms acting on the lunar rotation. A combination of solid‐body tides and viscous core‐mantle coupling have been proposed in previous studies. Here, we investigate whether viscoelastic deformation

Mars atmospheric pressure variations induce ground displacements through elastic deformations. The various sensors of the InSight mission were designed in order to be able to understand and correct for these ground deformations induced by atmospheric effects. Particular efforts were made, on one hand, to avoid direct pressure and wind effects on the seismometer and, on the other hand, to have a high

The pre‐collisional locations and geometries of the Lhasa terrane (LT) are critical to constrain the India‐Asia collision. However, the inclinations of the Cretaceous paleomagnetic data obtained from the northern limb of folds are obviously lower than those obtained from the southern limb, which cause large discrepant paleolatitudes of the LT prior to India‐Asia collision. Here, we carried out a new

The timing of crustal shortening and strike‐slip faulting along the East Kunlun Shan provides insight into the history of surface uplift and may constrain the time at which the Tibetan Plateau reached high elevations. We investigate a series of extensional basins and restraining bends along the Xidatan strand of the Kunlun strike‐slip fault, which provide an ideal setting to unravel the tectonic history

Geochemical patterns in the surficial media are complex because of the various processes involved in their formation. These processes may or may not relate to mineralization. Therefore, geochemical anomalies identified are usually subject to uncertainty. Geographically weighted lasso (GWL) was adopted in this study to model the non-stationary relationships between the geological/geographical features

Granitic aquifers, which occur in crystalline Basement bedrocks, are generally fresh and serve as potable water sources in many developing countries. In this study, we examine the chemical evolution processes, and water isotope geochemistry of a sparsely studied granitic aquifer in a sub-river watershed of the White Volta River Basin in West Africa. Our goal is to establish the sources of water that

There is a large compositional variation of I-type granites. Although partial melting and fractional crystallization are the two primary mechanisms for the variation, it is intriguing to know how they jointly work. This issue is addressed by a combined study of geochemistry and phase equilibrium modelling for a Triassic pluton from the Qinling orogen. The pluton consists of high-K, calc-alkaline I-type

Zinc and lead smelting slags from Ruda Śląska are unique in their chemistry and phase composition, which resemble rare natural rocks such as paralavas and melilitolites. Moreover, considering its size, we can treat a pyrometallurgical slag dump as a geological body. In slags from Ruda Śląska the assemblage melilite ± pseudowollastonite ± wollastonite ± plagioclase was discovered in glassy slag. High-temperature

The IUPAC-IUGS joint Task Group “Isotopes in Geosciences” recommends a value of (106.25 ± 0.38) Ga for the half-life of 147Sm, and a corresponding decay constant λ147 = (6.524 ± 0.024) × 10-12 a-1, both with a coverage factor k = 2. For the extinct radionuclide 146Sm two very different half-lives are used in the scientific community (c. 68 and 103 Ma), to such a degree that no consensus value can be

Seismic recordings from the USArray of the October 1, 2013 Sea of Okhotsk earthquake and the May 24, 2010 Western Brazil earthquake include high-amplitude SxP signals due to S-wave to P-wave scattering about 150 to 200 km below the 660-km discontinuity below these events. The scattering structures have been mapped previously and interpreted as fragments of folded crust that subducted into the uppermost

Multiple-layered coal seams widely exist in main coal mining areas of China. When these coal seams are exploited, the pillar mining method is always employed. This leads to many coal pillars left in the upper coal seams as a protective barrier. As a result, these residual pillars will not only cause the loss of coal resources but also could trigger environmental issues and a serious of mine disasters

The pore characteristics of the low-rank coal are different from medium- and high-rank coals. The low-temperature N2 adsorption (LP-N2A) measurements with a single low-rank coal were launched, and the dynamic change of pore structures under various pretreatment temperatures from 120°C to 300°C was studied. The isothermal curves of the DFS coal sample feature IV type, the hysteresis loops convert from

The Pamir gneiss domes represent the most extensive exposure of mid to lower crustal rocks in the Himalayan‐Tibetan orogen north of the India‐Asia suture zone. Unlike other domes in the Central and Southern Pamir, the Muztaghata dome stands out due to its higher metamorphic grade, more complex structural elements, and variable timing of metamorphism. In order to unravel the P‐T‐t history of the Muztaghata

We present high‐resolution tomographic images of isotropic P wave velocity and azimuthal anisotropy in the crust and uppermost mantle beneath NE Tibet by jointly inverting 62,339 arrival times of the first P and later PmP waves from 6,602 local earthquakes and 9 seismic explosions. Widespread low‐velocity zones in the middle crust contribute most of seismic anisotropy in the crust beneath NE Tibet

Electromagnetic loop systems rely on the use of non‐conductive materials near the sensor to minimize bias effects superimposed on measured data. For marine sensors, rigidity, compactness and ease of platform handling are essential. Thus, commonly a compromise between rigid, cost‐effective and non‐conductive materials (e.g. stainless steel versus fibreglass composites) needs to be found. For systems

Seismic modelling of the shallow subsurface (within the first few metres) is often challenging when the data are dominated by ground‐roll and devoid of reflection. We showed that, even when transmission is the only available phase for analysis, fine‐scale and interpretable P‐wave velocity (VP ) and attenuation (QP −1) models can still be prepared using full‐waveform inversion, with data being preconditioned

Abstract Satellite imagery was used to identify active neotectonic faults. The areas of greater fault density coincide with concentration zones of earthquake epicenters, including the largest of them (K ≥ 10). The earthquakes are confined to intersections of deep NE and NW striking faults. The Kulu–Tenka region can be considered as the area of interaction between the zones of dynamic influence of faults

Abstract Records of an IRIS broadband seismic station (AAK) deployed in the Tien Shan area were studied. An STS-1 seismometer made it possible to investigate ground motion velocity in the range of a few minutes. The result was to identify asymmetric anomalies in seismic noise that differ from Earth tidal variations. These indicate the effects of local tectonic processes during some time intervals.

Abstract This new seismic tomography study for the crust of southern Crimea and the northeastern Black Sea based on low-magnitude (M ≤ 3) earthquakes indicates significant heterogeneity of the crust at depths of 15–35 km. In the present paper we discuss the velocity distribution for P- and S-waves and give geological and tectonic interpretations in the context of collisional interaction between the

Abstract This study is concerned with the mineralogical composition of volcanic ejecta in the Central Kamchatka Depression: the plateau basalts of the Ozernaya Kamchatka, Kunch, and Nikolka Stratovolcano. These data were compared with rock compositions for some volcanoes in the Klyuchevskoi Group, the plateau basalts of Bakening Volcano, and data on xenoliths of two types, viz., the “island-arc” type

Abstract This paper presents the results of areal seismic studies in the deep structure of the Dzhau Tepe mud volcano, which is the largest of its kind on the Kerch Peninsula. It is the first time that data has been obtained concerning nearly vertical fluid-conducting structures beneath the volcano that supply material onto the ground during more active periods. A new approach is proposed for interpretation

Abstract This paper presents the results of mineralogical and crystallographic studies in the first Russian finding of a mineral belonging to the fluoride class, viz., knasibfite, which was found in fumarolic deposits discharged during the Great Tolbachik Fissure Eruption. We investigated its crystal structure to corroborate the fact that knasibfite is orthorhombic, sp. gr. Imm2; a = 17.181 (2), b

Intracontinental deformation is an inseparable element of the evolutionary history of orogenic belts. It can reactivate and intensely modify the structures of previous orogenic belts due to remote effects of plate margin orogenesis. As an important part of the Phanerozoic Central Asian Orogenic Belt (CAOB), the Alxa Block and its vicinity experienced multistage intracontinental deformation during the

The Western Kunlun orogenic belt (WKOB) located south of the Tarim Basin and the north-western margin of the Tibetan Plateau, was previously considered a complex orogenic belt that closed along the Kudi-Qimanyute suture zone (KQSZ) and Mazar–Kangxiwar suture zone (MKSZ) from north to south during Proto- and Paleo-Tethys. The MKSZ between the South Kunlun and Tianshuihai terranes was interpreted as

Gaseous elemental mercury (Hg0) concentrations in the atmosphere have been increasing due to anthropogenic activities since the onset of colonial mining in the 17th century. However, accurate measurements of atmospheric Hg, including temporal trends, are mostly limited to recent decades. Natural environmental archives including tree-rings show promise for reconstructing atmospheric concentrations of

The shock metamorphism of opal-A induced by supersonic microprojectile impacts in an advanced laser-induced projectile impact test (LIPIT) was investigated using synchrotron X-ray diffraction (XRD) and transmission electron microscopy (TEM). The three-dimensional topography of impact area is similar to the meteorite crater that has a circular outline with an uplifted rim. The post-impact synchrotron

Lawsonite is an abundant hydrous mineral in oceanic crust, sediments, and metasomatic rocks at depths of ~45 to 300 km in most subduction zones, but it is rarely preserved in the geologic record because it commonly transforms to epidote and other minerals during prograde or retrograde metamorphism. Owing to the significance of lawsonite for water and element cycling in subduction zones, occurrences

The newly discovered Zhaojinggou TaNb deposit in the northern margin of the North China Craton contains ore reserves of more than 38 Mt. at an average grade of 0.013 wt% Ta2O5 and 0.012 wt% Nb2O5. The TaNb mineralization is mainly hosted in a peraluminous, albite granite body, which is about 400 m long and 20 to 100 m wide, with a surface exposure of ~0.05 km2. Granitic pegmatites and greisen veins

Stream carbon fluxes are one of the major components in the global C cycle, yet the discrimination of the various sources of stream carbon remains to a large extent unclear and less is known about the biogeochemical transformations that accompany the transfer of C from soils to streams. Here, we used patterns in stream water and groundwater δ13C values in a small forested tropical headwater catchment

Data on the chromium stable isotope composition of planetary reservoirs have the potential to provide information about core formation, partial melting and conditions of the Moon formation. In order to detect the small Cr isotopic differences between various reservoirs in the solar system, their compositions need to be precisely constrained. The current BSE value of δ53Cr = −0.11 ± 0.06‰ (Sossi et

Carbonated hydroxy-apatite (Ca10-b(NH4,K,Na)2b(PO4)6-y[(CO3)2x+(3/2)y(OH)2–2x]; CHAP) was synthesized in batch-type experiments by mixing of calcium (Ca)- and phosphate-bearing aqueous solutions and the transformation of calcite powder in aqueous solution between 11° and 65 °C. Compositional changes of the mother solution and solid phase products were followed by powder XRD, scanning-electron microscopy

The long-term potential capacity for soils to deliver essential elements to plants and the soil solution is often assessed using aqua regia (AR) extractions, and understanding specific mineral contributions to extracted element concentrations is central to the accurate interpretation of such data. The objective of this study was to assess whether the supplying quantitative soil mineralogy data to the

Although volumetrically minor in the upper continental crust, pegmatites host lots of rare-metal mineralization (e.g., Li, Be). Pegmatites and associated mineralization were generally thought to originate from extreme differentiation of a parent granite system. We propose an alternative model to interpret the genesis of pegmatite and factors controlling Li mineralization based on combined Nd and Li

The Acasta Gneiss Complex (AGC) of the Northwest Territories, Canada, contains some of the oldest evolved terrestrial crust and has a sustained record of more than a billion years of magmatism (>4.0–2.9 Ga). These rocks provide an opportunity to investigate the nature of continental crust formation on the early Earth. Because complexities in zircons and bulk rocks are characteristic of the early Earth

Silicon (Si) isotopic compositions of authigenic Si-bearing materials can be powerful tracers of geological Si cycling and reconstruction of Earth’s climate. Interpretations of Si isotope data, however, are complicated by an inadequate understanding of natural Si isotopic fractionation pathways. This study investigated Si isotope fractionation between hydrothermal fluids and amorphous silica sinters

Hydrothermal fluids in orogenic and intrusion-related (mesothermal) gold deposits are dominated by saline-aqueous-carbonic fluids, commonly represented by the ternary system H2O-NaCl-CO2. The phase equilibria, thermodynamic properties (PVTx, density, compositions of fluid phases) and quartz dissolution-precipitation behavior in the H2O-NaCl-CO2 system, which are still poorly constrained, are of great

In many volcanic settings, eruptive deposits experience prolonged cooling in the presence of water, such as in subglacial or submarine eruptions. Under these conditions, volcanic glass will rehydrate and record the isotopic composition of the water. This isotope exchange is moderated by H2O solubility and diffusivity in the glass. In this study, we report results from glass hydration experiments conducted