Hasil untuk "Geology"

Yupeng LI, Yaning CHEN, Fei WANG et al.

Tajikistan, a mountainous country and a vital water tower for Central Asia, is becoming increasingly vulnerable to snow drought under climate change, threatening its snow- and glacier-fed streamflow. Yet, the impacts of snow drought on the regional hydrology remain insufficiently understood. In this study, we integrated multisource data, including the Fifth Generation European Centre for Medium-Range Weather Forecasts Atmospheric Reanalysis for Land Applications (ERA5-Land) data and hydrological station data, to systematically assess the snow drought patterns and their impacts on streamflow during 1950–2023. We identified snow drought events based on precipitation and snow fraction anomalies relative to climatological means and classified them into warm snow drought, dry snow drought, and warm&dry snow drought. The results revealed that snow drought was a recurrent phenomenon, occurring in 51.70% of the years during the study period, with warm&dry snow drought accounting for 21.90% of the total events. Both the frequency and severity exhibited pronounced spatial variability, largely governed by the elevation and snowfall fraction. Specifically, the frequency of warm snow drought was negatively correlated with the snowfall fraction, decreasing on average by 0.20 per unit increase in snowfall fraction, whereas the frequency of dry snow drought was positively correlated, increasing by 0.07 per unit increase. The streamflow analysis results demonstrated that snow drought typically reduced the warm-season discharge by 5.00%–18.00% in certain rivers, thereby exacerbating the water stress during the dry season. The results of this study advance our understanding by explicitly linking the types of snow drought to hydrological responses in Central Asia’s high mountains, providing a scientific basis for climate adaptation and sustainable water resource management in Tajikistan.

Rafael León, Carlos R. Cánovas, M. Dolores Basallote et al.

El talio (Tl) es un elemento no esencial para los seres vivos y un metal ubicuo en la corteza terrestre, con una concentración media de alrededor de 0.5 mg/kg. Este metal se obtiene comúnmente como subproducto durante el procesado de concentrados de pirita y sulfuros polimetálicos (Cu-Pb-Zn). El Tl puede exhibir un alto potencial de citotoxicidad y genotoxicidad para los seres humanos en sus dos estados de oxidación principales (I y III). El contenido de Tl de suelos y aguas superficiales está fuertemente condicionado por el substrato geológico, y aunque las concentraciones en suelos oscilan entre 0.1 y 2 mg/kg, se pueden observar elevadas concentraciones en la corteza terrestre asociadas a sulfuros o minerales ricos en potasio. La meteorización de rocas ricas en estos minerales conduce a niveles crecientes de este metal en suelos, aguas y sedimentos. En el presente trabajo se analiza el origen, la movilidad y el destino final del Tl en áreas afectadas por drenaje ácido de mina en la Faja Pirítica Ibérica, uno de los distritos de sulfuros masivos polimetálicos más importantes del mundo.

Benjamín Castro-Cancino, Waldo Pérez-Martínez, Paulina Vidal-Páez et al.

In the mountainous and foothill areas of Santiago, Chile, debris flows and debris floods have been recurrent over recent decades, triggered by short-duration, high-intensity summer rainfall events. These events have caused significant damage to infrastructure and have affected the population, including loss of human lives. This study assesses the susceptibility to debris flow and debris flood generation in the Arrayán and Gualtatas stream basins, located in the Metropolitan Region, using satellite and cartographic data. A Susceptibility Index (SI) was determined through the analysis of 14 conditioning factors, grouped into three main categories: geology, geomorphology, and soil conditions. The weighting and ranking of each factor’s importance were carried out using the Analytic Hierarchy Process (AHP). The results, presented in a susceptibility map, indicate that 60.78% of the study area exhibits low to very low susceptibility, 24.64% moderate susceptibility, and 14.58% high to very high susceptibility, concentrated in stream headwaters, steep slopes, and areas with unconsolidated deposits. Recent debris flow events that have reached urban areas coincide with high-susceptibility zones, validating the methodology and cartographic products, which can support land-use planning and risk management efforts.

Rob Felix, Jaap Bouwman, Baudewijn Odé et al.

This paper presents all available information on the Orthoptera of the Socotra Archipelago, an area well-known for its endemic flora and fauna. General information is provided about the climate and geology of the Socotra Archipelago. The various habitats where grasshoppers have been found are described and illustrated, followed by a concise history of Orthoptera research on Socotra. Besides an identification key to the species, additional information about the material examined, taxonomy, diagnostic notes, distribution and occurrence, including maps, habitat, biology and bioacoustics, is provided for each species. In total, 65 Orthoptera species are reported here from Socotra, Abd el Kuri, Samha and Darsa, including Oecanthus castaneus Felix & Bouwman, sp. nov. and two unknown species assigned to Ectatoderus. Of these 65 species, 30 (46%) are endemic to the Socotra Archipelago. Re-descriptive notes on Acrotylus innotatus Uvarov, 1933 and Glomeremus capitatus Uvarov, 1957 are provided, including the description of the female of the latter species and the male of Oxytruxalis ensis (Burr, 1899). Acrotylus innotatus Uvarov, 1933, Dictyophorus griseus (Reiche & Fairmaire, 1850), Eumodicogryllus chivensis (Tarbinsky, 1930), Ochrilidia geniculata (Bolívar, 1913), Sphingonotus rubescens (Walker, 1870) and S. balteatus (Serville, 1838) are recorded for the first time from the Archipelago. Bioacoustics are presented for: Ochrilidia socotrae Massa, 2009, Stenohippus socotranus (Popov, 1957), Sphingonotus ganglbaueri Krauss, 1907, S. insularis (Popov, 1957), Acheta rufopictus Uvarov, 1957, Eumodicogryllus chivensis (Tarbinsky, 1930), Ectatoderus guichardi Gorochov, 1993 as well as two other species assigned to Ectatoderus, Oecanthus castaneus Felix & Bouwman, sp. nov., Ruspolia aff. R. basiguttata (Bolívar, 1906) and Pachysmopoda abbreviata (Taschenberg, 1883). Red List Assessments for 29 endemic species have been prepared including Oxytruxalis ensis (Burr, 1899) (Critically Endangered, CR), Cataloipus brunneri (Kirby, 1910) (Endangered, EN) and Glomeremus capitatus Uvarov, 1957, Phaneroptila insularis Uvarov, 1957, Phaulotypus granti Burr, 1899, Socotracris kleukersi Felix & Desutter-Grandcolas, 2012, Socotrella monstrosa Popov, 1957 and Xenephias socotranus Kevan, 1973 (all Vulnerable, VU).

Pilar Ortíz Sandoval, Margarita Aguilera‐Gómez, Anna Kostka et al.

Abstract Anthropogenic activities, such as industrial processes, urban development, intensive agriculture and waste disposal, have significantly contributed to the continuous introduction and accumulation of a wide array of xenobiotic compounds into natural ecosystems. Among them, emerging contaminants (ECs) such as pharmaceuticals, endocrine‐disrupting chemicals (EDCs), and per‐ and polyfluoroalkyl substances (PFAS) are of increasing concern due to their persistence, bioactivity and limited regulation. ECs enter ecosystems through diverse pathways including wastewater discharge, agricultural runoff and atmospheric deposition. Once released, many of these xenobiotics can bioaccumulate in organisms and enter the food chain, posing serious risks to food safety and public health. Traditional physico‐chemical remediation methods are often insufficient or environmentally taxing, prompting a shift toward bio‐based alternatives like bioremediation. These approaches, which rely on the activity of microbial communities to degrade pollutants, offer more sustainable solutions but require further interdisciplinary research to optimise their use. The One Health framework provides an effective model for addressing the complex risks posed by xenobiotics. This research programme aims to harmonise methodologies for cumulative dietary risk assessment across Europe and explore microbial strategies for xenobiotic degradation. By integrating microbiomics, toxicology, environmental science and food safety, this approach supports the development of safer food systems and more effective pollution management in line with the ‘farm to fork’ and One Health principles.

M. Marín-Martín, E. Tejedor, G. Benito et al.

<p>The Mediterranean basin, a recognized climate change hotspot, faces increasing hydroclimatic pressures, particularly from severe drought and precipitation events. To assess contemporary changes and potentially manage future impacts, it is crucial to understand the long-term context of this variability beyond the relatively short instrumental record. This study utilizes tree-ring records to reconstruct past hydroclimate in the Iberian Range of eastern Spain, a water-sensitive Mediterranean environment. We present a well-replicated tree-ring width chronology from <i>Pinus sylvestris</i> and <i>Pinus nigra</i> trees that calibrates and verifies significantly against cumulative instrumental precipitation over a 320 d period ending in June (<span class="inline-formula"><i>r</i></span> <span class="inline-formula">=</span> 0.749; <span class="inline-formula"><i>p</i></span> <span class="inline-formula">&lt;</span> 0.01). The resulting 520-year reconstruction reveals substantial multi-centennial variability in precipitation and reveals an increase in the frequency and intensity of hydroclimatic extremes (both wet and dry) during the late 20th and early 21st centuries compared to the longer-term baseline. The reconstruction has a spatial representativeness centred over eastern and central Iberia and covaries with independent historical drought indices derived from rogation ceremony records during the late 18th and early 19th centuries. The documented intensification of hydroclimatic extremes is consistent with climate change projections and provides a baseline for evaluating ecosystem resilience and water resource vulnerability.</p>

Jin Lee, Sung-soo Kim, Do-hun Lee

This study was conducted to identify changes in insect composition and function before and after the construction of onshore wind farms. We investigated insect fauna, composition, and functional groups in grassland and forest sites at the operational Muchang Wind Farm (MC) in Yeongdeok and Yeongyang, Gyeongsangbuk-do, and the planned Gasan Wind Farm (GS) in Jeongsun, Gangwon-do, Korea. Insects were collected using a sweeping net, pitfall traps, and light traps. A total of 12 orders, 75 families, and 2,497 individuals were collected across the study sites. Among taxonomic groups, the order with the highest species and individual counts was Lepidoptera, with 222 species and 628 individuals (25.0%), followed by Coleoptera, with 81 species and 241 individuals (23.5%). Additionally, based on functional groups such as herbivores, predators, decomposers, etc., the results reveal distinct differences in the proportion of these groups between grasslands created by habitat disturbance at the operational MC site and those at the planned GS site. The findings of this study provide valuable insights into the effects of habitat changes due to onshore wind farm establishment on insect communities.

J. Lee, W. M. Hannah, D. C. Bader

<p>In the Energy Exascale Earth System Model (E3SM) Multi-scale Modeling Framework (MMF), where parameterizations of convection and turbulence are replaced by a 2-D cloud-resolving model (CRM), there are multiple options to represent land–atmosphere interactions. Here, we propose three different coupling strategies, namely the (1) coupling of a single land surface model to the global grid (MMF), (2) coupling a single land copy directly to the embedded CRM (SFLX2CRM), and (3) coupling a single copy of land model to each column of the CRM grid (MAML). In the MAML (Multi-Atmosphere Multi-Land) framework, a land model is coupled to CRM at the CRM-grid scale by coupling an individual copy of a land model to each CRM grid. Therefore, we can represent intra-CRM heterogeneity in the land–atmosphere interaction processes. There are 5-year global simulations run using these three coupling strategies, and we find some regional differences but overall small changes with respect to whether a land model is coupled to CRM or a global atmosphere. In MAML, the spatial heterogeneity within CRM induces stronger turbulence, which leads to the changes in soil moisture, surface heat fluxes, and precipitation. However, the differences in the MAML from the other two cases are rather weak, suggesting that the impact of using MAML does not justify the increase in cost.</p>

João Carlos Baptista Jorge da Silva

O presente trabalho apresenta a célula K0-UFBa, onde é mostrado um dispositivo eficiente para a determinação do coeficiente de empuxo no repouso de solos a partir de amostras indeformadas. A célula K0-UFBa foi desenvolvida e licenciada no LabGeo da Escola Politécnica da Universidade Federal da Bahia (UFBa), Brasil. Seus principais componentes e detalhes de montagem são mostrados. O desenvolvimento do equipamento baseou-se nos ensaios de odômetro, porém com confinamento lateral de água, que por ser incompressível, não permite deformação neste sentido, mantendo a condição de K0. A fim de avaliar os resultados da célula K0 em amostras indeformadas obtidas de dois poços escavados em solo residual, esses resultados foram comparados com os ensaios DMT, que foram feitos próximo aos poços. Os resultados mostraram comportamento semelhante ao longo da profundidade em ambas às áreas de ensaio quando comparados com os resultados da célula K0 e ensaios de campo (DMT). A pequena variação dos valores deve-se principalmente à heterogeneidade do solo residual, associada a fatores como erosão superficial, cimentação devido à presença de óxidos e histórico de tensões originadas da rocha mãe.

Kathrin Heine, Kathrin Heine, Viktoria Kichmann et al.

This study analyzed skeletal development, body condition, and total body fat development of growing heifers. A total of 144 female primiparous Holstein cattle from four commercial dairy farms with different degrees of stillbirth rates were examined during the rearing period. This included measurements in body condition, fat tissue, metabolic, and endocrine factors. Pelvic measurements and the sacrum height were analyzed to assess skeletal development. The body condition was classified via body condition scoring, bioelectrical impedance analysis (BIA), back fat thickness measurements, and the body mass. For the first time, BIA was used as an appropriate method to evaluate the fat tissue content of cattle throughout the rearing period. This analysis technique can be performed on heifers aged 8–15 months. Throughout that period, the fat content decreased while the skeletal development increased. In addition, high free fatty acid concentrations in serum of the animals with high frame development were found, supporting our hypothesis that stored energy of body fat deposits is used for skeletal growth. Furthermore, we were able to demonstrate complex endocrine relationships between fat metabolism and skeletal growth by using specific markers, such as leptin, insulin growth factor-1 (IGF-1), and estradiol (E2). Food analysis showed high crude protein (CP) levels in the total mixed ration above recommendation for daily protein intake of all farms. However, there was a positive correlation between CP and the body frame measurements in our study. In summary, we established a novel regression formula for BIA analysis (“BIA-Heine”) in heifers to evaluate the body composition throughout different ages and physiological stages in the development of heifers. This special formula allows the evaluation of fat tissue without a whole-body analysis and therefore provides an innovative technique for animal welfare support.

Ershe XU, Guoliang TAO, Zhiming LI et al.

The mineral composition, lithofacies association, pore-fracture type, pore structure and pore development control of the Qianjiang Formation shale oil reservoir in the Qianjiang Sag of the Jianghan Basin were studied using thin section petrography, scanning electron microscopy, mercury injection-liquid nitrogen adsorption and 3D reconstruction of micro-CT. The main lithofacies of Eq34-10 rhythm (the tenth rhythm in the fourth submember of the third member of the Qiangjiang Formation) are laminated argillaceous dolomite, laminated dolomitic (calcareous) mudstone and mirabilite filled laminated dolomitic mudstone. The main reservoir porosity includes interlayer fractures, intergranular pores and intergranular solution pores. The pore development of inter-salt shale oil reservoir is mainly controlled by lithology and lithofacies, and the pore development degree of mirabilite filled laminated dolomitic mudstone, laminated dolomitic (calcareous) mudstone and laminated[JP3]argillaceous dolomite increase accordingly. Macro-pores are the most developed porosity in the laminated argillaceous dolomite facies, with the best pore connectivity and oil-bearing properties, and is the dominant lithofacies in the inter-salt shale oil reservoir and the most favorable exploration target.

Ehsan Saeed, Saeedeh Senemari, Bijan Maleki et al.

The present study investigates the geochemical properties of potential source rocks in the eastern Caspian Basin from Alborz structural zone. For this purpose, sections of Suchelma and Purva in south of Neka and an outcrop in south of Sari were selected. The studied samples of sedimentary source rocks of the Paleocene age were analyzed based on Rock-Eval analysis method. The results of Rock- Eval pyrolysis and organic petrography results of probable source rock sediments in one of the exploration wells of Gorgan plain were also studied. According to the results, most of the outcrops samples are immature and were deposited in a regressive continental environment. The samples of exploration borehole studied, are good in terms of organic matter richness but in terms of the amount of kerogen maturation are immature. According to the results of this study, these samples have weak hydrocarbon generating power and total organic carbon content of about 1% as well as kerogen type III. It was also specified in the determination of organic facies that most of the mentioned samples show deep environmental conditions adjacent to orogenic and continental sites and are deposited in a regressive environment. Keywords: Source rock, Rock- Eval experiment, Maturity, Southern Caspian Basin, Hydrocarbon generation potential.   Introduction The Caspian Sea region is well known for its abundant oil reserves and oil and gas production has played an important commercial role in the region for more than 150 years especially in Azerbaijan and to a lesser extent in Turkmenistan (Smith- Rouch 2006). Identification of hydrocarbon systems in the Caspian sedimentary basin is of great importance for exploratory studies and to achieve the production of hydrocarbon resources. One of the main pillars of any oil system is the source rock. Therefore, it is necessary to identify the source rock and determine its location in any system to avoid imposing exorbitant costs and unsuccessful excavations. The relatively low geothermal gradients (around 1.5°C 100m-1) from rapid burial provide favorable thermal conditions for the preservation of hydrocarbons at relatively great depths (up to10+ km) (Nadirov 1990). A petroleum source rock is defined as any rock that has the capability to generate and expel enough hydrocarbons to form an accumulation of oil or gas. Definitions that do not include migration and accumulation are too general, because in a sense practically all rocks contain organic matter (OM) form some hydrocarbons. A potential source rock is one that is too immature to generate petroleum in its natural setting but will form significant quantities of petroleum when heated in the laboratory or during deep burial (Hunt 1996). The main source- rocks in the south Caspian basin are considered to be Paleogene- Miocene deposits (Maykop/ Diatom) (Guliyev et al. 2001). Paleocene deposits in Iran are important for hydrocarbon reserves due to their organic matter as a source rock. Therefore, this study investigates the hydrocarbon generation potential of Paleocene sediments in the east of southern Caspian Basin. Materias and Methods Three outcrops in Mazandaran province were selected for this study. From each of Suchelma and Purva outcrops, six and seven samples, respectively, and from south of Sari two samples of potential source rock sediments of the Paleocene age were analyzed for Rock- Eval pyrolysis. The Rock- Eval pyrolysis and Organic Petrography results of eight samples of the Paleocene deposits in one of the exploration wells of Gorgan plain were also studied. The Rock- Eval pyrolysis method has been extensively used for oil and gas exploration in sedimentary basins over the world (Behar et al. 2001). Vitrinite reflectance is the most reliable maturity parameter for measuring thermal maturity of sedimentary organic matter (Tokatli et al. 2006).   Discussion of Results and Conclusions According to the results, most of the outcrops samples harvested were poor in terms of total organic carbon content and in terms of kerogen maturity were before the oil window. Therefore, they are weak in terms of hydrocarbon generation potential. These samples contain kerogen type IV. Also in determining the organic facies, it was found that most of the sediments were deposited in a continental regressive environment. The well samples are good in terms of organic matter richness, immature in terms of the amount of kerogen maturation and weak in terms of hydrocarbon generation potential. The measurement results of vitrinite reflectance also confirmed that the borehole samples were immature. These samples contain kerogen type III. It was also specified in the determination of organic facies that most of the well samples show deep environmental conditions adjacent to orogenic sites and are deposited in a regressive environment

Jinyu Chen, Fabrice Gaillard, Arnaud Villaros et al.

The original PDF version of this Article contained an error in which Fig. 3 and its legend were omitted and Equations 5 and 6 contained errors.This has been corrected in the PDF version of the Article. The HTML version was correct from the time of publication.

A. E. Shalaginov, N. N. Nevedrova, I. O. Shaparenko

In the regions of high seismic activity, investigations of fault zones are of paramount importance as such zones can generate seismicity. A top task in the regional studies is determining the rates of activity from the data obtained by geoelectrical methods, especially considering the data on the faults covered by sediments. From a practical standpoint, the results of these studies are important for seismic zoning and forecasting of natural and anthropogenic geodynamic phenomena that may potentially occur in the populated areas and zones allocated for construction of industrial and civil objects, pipelines, roads, bridges, etc. Seismic activity in Gorny Altai is regularly monitored after the destructive 2003 Chuya earthquake (M=7.3) by the non-stationary electromagnetic sounding with galvanic and inductive sources of three modifications. From the long-term measurements that started in 2007 and continue in the present, electrical resistivity and electrical anisotropy are determined. Our study aimed to estimate the variations of these electrophysical parameters in the zone influenced by the fault, consider the intensity of the variations in comparison with seismicity indicators, and attempt at determining the degree of activity of the faults. Based on the results of our research, we propose a technique for measuring and interpreting the data sets obtained by a complex of non-stationary sounding modifications. The technique ensures a more precise evaluation of the electrophysical parameters. It is concluded that the electric anisotropy coefficient can be effectively used to characterize the current seismicity, and its maximum variations, being observed in the zone influenced by the fault, are characteristic of the fault activity. The use of two electrophysical parameters enhances the informativeness of the study.

DANIEL B. BLAKE, ANDREA TINTORI, TEA KOLAR-JURKOVŠEK

The Paleozoic-Mesozoic transition saw the disappearance of asteroid stem groups and the ascent of the crown group, but late Paleozoic and Triassic asteroids are rare and transition events are poorly documented. Three new Middle and Late Triassic specimens augment existing data; included are a specimen of Trichasteropsis weissmanni from Germany, a specimen of Trichasteropsis? sp. indet. from Italy, and a possible member of the extant Poraniidae from Slovenia. Presence of a small ossicle at the interbrachial midline and adjacent to the marginal series of the new T. weissmanni specimen is consistent with similar expressions not only of other trichasteropsids but also occurrence of two interbrachial ossicles in Paleozoic, stem-group asterozoans; presence is in turn consistent with a hypothesis of derivation of the axillary/odontophore coupling from two ossicles rather than direct derivation of the crown-group odontophore from a single stem-group axillary. Morphology of Trichasteropsis? sp. indet., including, for example, the evenly-tapering arms are reminiscent of those of diverse crown-group asteroids whereas the enlarged distal arms of T. weissmanni are unique, the morphology of T? sp. indet. thereby potentially indicative of a plesiomorphic, stemward positioning within the Trichasteropsiidae. The range of the Poraniidae is tentatively extended to the Carnian. Similarities shared by the Poraniidae and the Trichasteropsiidae suggest stemward positioning within crown-group diversification; however, known Triassic fossils do not appear closely related to extant taxa identified in recent molecular studies as basal within the crown-group. A temperate climate is suggested as preferred by the Triassic asteroids rather than a tropical, warmer one.

A. Escher, W. Watt

W. Tutin, R. West

G. Packham

R. J. Adie, B. Gunn, G. Warren

V. Prest