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Based on a reassessment of the papyri Pap. Berlin P 15871 and 1582A+B with the correction of several readings, particularly one of the three determinatives of (i) "shrine", the key word for their earlier interpretations, it is suggested that the architectural drawings do not show a rock cut temple or a hemi-speos but KV 5, the so-called tomb of the sons of Ramesses II in the Valley of the Kings. Differences in the handwriting, in the depiction of the bedrock pattern surrounding the rectangular rooms, and other observations suggest that more than one person was involved in the creation of the architectural drawings. As suggested in the past, they belonged to at least two different papyri. Terms referring to work in progress indicate that the papyri are related to work in progress, as opposed to other architectural drawings which represent the beginning or final stages of tomb construction projects. [ABSTRACT FROM AUTHOR]

To prevent economic losses caused by borehole breakout during coalbed methane extraction, it is essential to understand the mechanisms of borehole deformation and the distribution patterns of stress-induced fractures. However, previous research efforts have failed to address these aspects adequately. This article investigates the geometry nature of borehole breakout in pre-loaded coal samples under various factors using the discrete element method (DEM). The results revealed significant distinctions in borehole breakout behaviour between coal and other geological materials. In the case of coal, the geometry of breakout is particularly pronounced during the initial stages of failure. However, as stress differentials intensify, the geometry undergoes relatively minimal alterations compared to other rock formations, suggesting a relatively weak sensitivity. The geometry of the borehole breakout in the coal seam widened and deepened as the stress difference increased and the coal elastic modulus decreased. The breakout volume first increased significantly and remained stable as the stress difference increased. A critical threshold line is proposed to represent the macroscopic failure of coal rock caused by drilling, considering the combined effects of elastic modulus and stress differential. The region below the threshold line represents the trend of macroscopic failure after drilling instability, while the region above the threshold line indicates a stable trend. The findings of this study have practical implications for engineering applications. Highlights: Various factors (stress difference, borehole size, coal elastic modulus) influence the geometry nature of borehole breakout in coal. Breakout depth and breakout width in simulated coal rock show a linear positive correlation with stress differences. Borehole deformation in coal seams is apparent once it occurs but shows lower sensitivity to the in-situ stress difference compared to sandstone and limestone,. A decisive criterion for determining whether borehole breakout leads to macroscopic fracture in coal rock is suggested by considering the joint impact of elastic modulus and stress difference. [ABSTRACT FROM AUTHOR]

In this study, the mechanical behavior of novel fully grouted cable rock bolts made of basalt fiber–reinforced polymer (BFRP) was investigated, which included pullout and double-shear joint behavior. Three BFRP cables were prepared: (1) single-tendon; (2) untwisted multiple-tendon; and (3) twisted multiple-tendon. In the pullout tests, the effects of cable type, borehole diameter, and encapsulated length were studied. However, the influence of the pretension load level was focused on in the double-shear joint tests. The results suggested that an overly thick grout annulus significantly reduced the pullout strength and stiffness. For the BFRP cable with multiple tendons, the initial pullout stiffness was enhanced compared with the BFRP cable with a single tendon due to better interfacial bonding with the grout. In the double-shear joint tests, the pretension of the cable significantly improved the shear capacity and stiffness. With an enhancement in the confinement from pretension, the partial failure of the grout at an early stage could be prevented. The parallel and twisted-tendon BFRP cable rock bolts had larger failure displacements than the single-tendon cable. This analytical study found that a pullout analytical model available in the literature was accurate when back-calculating the stress conditions along the rock bolt. The predicted shear capacity of the rock joint showed good agreement with the experimental values. A parametric study indicated that the joint shear capacity was sensitive to the tensile and shear strengths of the cable but was irrelevant to the cable moduli. Considering the effectiveness of pretension and creep safety for BFRP, a suitable range for the pretension load was suggested. Practical Applications: This study attempts to promote the use of novel, fully grouted cable rock bolts made of basalt fiber–reinforced polymer (BFRP) materials in geotechnical engineering applications. Different types of cable rock bolts are produced, which include single-tendon, untwisted multiple-tendon, and twisted multiple-tendon cables. In the pullout tests, the untwisted multiple-tendon cable exhibited the highest pullout capacity, because of its better interfacial bonding with the grout. From the double-shear joint tests, the pretension of the cable could significantly improve the shear capacity and stiffness. In general, the BFRP cable rock bolts could have a competitive mechanical behavior compared with the steel rock bolts. The respective analytical models for pullout and double-shear joint specimens have proved to be accurate for predicting the mechanical responses of the cable rock bolts. These concise but reliable analytical models could allow researchers and designers to better utilize these novel cable rock bolts in potential applications. [ABSTRACT FROM AUTHOR]

The Rochechouart impact structure in the northwestern part of the French Massif Central (FMC) has a great diversity of impactites, including monomict impact breccias, suevite, and impact melt rocks (IMRs). The structure is strongly eroded, which allows the study of impactites of the crater fill and the transition into the crater floor. The FMC has had a multistage geological evolution from the late Neoproterozoic to the Ordovician (600–450 Ma) until the later stages of the Variscan orogeny (~300 Ma). Previous geochronological work on Rochechouart has been focused mainly on the impactites and constraining the impact age, and scarce work has been done on the FMC‐related target rocks. Here, U‐Pb isotope analysis by LA‐MC‐ICP‐MS has been conducted on zircon from two IMRs from the Recoudert and Montoume localities, and from a monzodiorite, a paragneiss, and two amphibolite samples of the basement to the impact structure. Zircon from the target rocks yielded mainly Neoproterozoic to Carboniferous ages (~924 to ~301 Ma) that can mostly be correlated to different stages of the geological evolution of the FMC. The monzodiorite also yielded a Permian age of 272 ± 12 Ma. Zircon from the IMRs, and especially from the Montoume sample, gave a comparatively higher diversity of Neoproterozoic to Jurassic ages (~552 to ~195 Ma). Provenance analysis for the zircon age populations of the impactites compared to those of the basement rocks shows overall poor correlation between the two age groups. This suggests that other target lithologies were involved in the formation of these impact melts as well. Post‐Variscan and preimpact ages (281–226 Ma) obtained for both melt rocks probably reflect a previously unconstrained event in the evolution of the regional geological history. Ages similar to the currently most widely accepted impact age of ~204–206 Ma were obtained from both IMR samples. In addition, the Montoume melt rock yielded several post‐204 Ma ages, which might reflect a to date unconstrained, about 194 Ma postimpact thermal/hydrothermal event. [ABSTRACT FROM AUTHOR]

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

Hausdorf, B., Xu, J., BAMBERGER, S. (2024) Repeated colonization of the Northern Limestone Alps from the Southern Limestone Alps by the rock‐dwelling snail species Cochlostoma henricae—Zoologica Scripta, 00, 000–000. The evolution of biogeographic disjunctions in the Southern and Northern Limestone Alps has been studied only in a few taxa. Cochlostoma henricae (Strobel, 1851) is a land snail species restricted to limestone rocks showing such disjunctions. We studied the phylogeny and population structure of this species using genomic ddRAD data to better understand the differentiation of the species in the Southern Alps and the origin of the isolated occurrences in the Northern Limestone Alps. Phylogenetic and population‐genetic analyses of the ddRAD data revealed a subdivision of the C. henricae populations into a western cluster and an eastern cluster. These clusters were probably separated by glaciers that extended from the Piave Valley to the margin of the Alps. Such a longitudinal subdivision is a common pattern of several species in the Southern Limestone Alps. However, the boundaries between western and eastern population groups differ between taxa. Cochlostoma henricae colonized the Northern Limestone Alps at least twice. The population from Breitenwang in Tyrol originated from the western group, whereas the occurrences in the Salzkammergut are from the eastern group. These and similar disjunctions of several other land snails show that even species with limited dispersal abilities could cross the Alps repeatedly by passive long‐distance dispersal events. A subdivision of C. henricae into three subspecies, proposed based on shell characters, does not correspond to its population‐genetic structure. Instead, the eastern and western population groups represent distinct evolutionary units. [ABSTRACT FROM AUTHOR]

Satellite imagery has become a major source for identifying and mapping terrestrial and planetary landforms. However, interpretating landforms and their significance, especially in changing environments, may still be questionable. Consequently, ground truth to check training models, especially in mountainous areas, can be problematic. This paper outlines a decimal format, [dLL], for latitude and longitude geolocation that can be used for model interpretation and validation and in data sets. As data have positions in space and time, [dLL] defined points, as for images, can be associated with metadata as nodes. Together with vertices, metadata nodes help build 'information surfaces' as part of the Digital Earth. This paper examines aspects of the Critical Zone and data integration via the FAIR data principles, data that are; findable, accessible, interoperable and re-usable. Mapping and making inventories of rock glacier landforms are examined in the context of their geomorphic and environmental significance and the need for geolocated ground truth. Terrestrial examination of rock glaciers shows them to be predominantly glacier-derived landforms and not indicators of permafrost. Remote-sensing technologies used to track developing rock glacier surface features show them to be climatically melting glaciers beneath rock debris covers. Distinguishing between glaciers, debris-covered glaciers and rock glaciers over time is a challenge for new remote sensing satellites and technologies and shows the necessity for a common geolocation format to report many Earth surface features. [ABSTRACT FROM AUTHOR]

This study conducts uniaxial compression tests on granite samples with prefabricated fissures to investigate the damage mechanism of granite containing non-penetrating joints. These tests combine indoor experiments with three-dimensional discrete element numerical simulations. Stress–strain curves for the rock specimens and the microscopic crack extension mechanism are obtained under varying nodal configurations and by adjusting the inclination angle, penetration, and the number of prefabricated fissures. Results indicated that jointed rocks exhibit a more pronounced plastic deformation capacity than intact rocks when subjected to uniaxial compression. For rock mass strength, the strength of the jointed rock displays a parabolic trend, first decreasing and then increasing, with the increase in joint inclination angle. The minimum value is observed at an inclination angle of 20°–40°. In contrast, the strength of the jointed rock shows a consistent decline with the increasing joint penetration degree and joint count. For rock damage patterns, rock specimens with a nodal inclination angle of 0° primarily experience vertical shear and splitting tensile damage. As the inclination angle increases (0° < α < 90°), the specimens shift towards coplanar shear damage. However, when the joint inclination angle reaches 90°, the mode of failure shifts to a pure form of splitting tensile damage. Specimens with greater penetration lean more towards coplanar shear damage. As the number of nodal joints increases, the rocks transition from shear damage to mixed tensile-shear damage. [ABSTRACT FROM AUTHOR]

Species distribution and activity patterns vary across regions, and these patterns reveal key information about the biology of a given species. However, such data in Niubeiliang National Nature Reserve located in the Qinling Mountains, Shaanxi Province, China, are inadequate due to limited monitoring studies. From September 2017 to December 2019, 57 infrared cameras were installed to monitor species distribution relative to distance from National Highway 210, and spatial and temporal activity patterns in Niubeiliang National Nature Reserve (elevation range 1,100 to 2,802 m). Sixteen species of mammals were recorded in our survey. The 4 most frequently detected species were Reeves's Muntjac (Muntiacus reevesi), Wild Boar (Sus scrofa), Pere David's Rock Squirrel (Sciurotamias davidianus), and Golden Takin (Budorcas taxicolor bedfordi). Daily patterns of these species indicated that Reeves's muntjacs and golden takins were more active at dawn and dusk, whereas wild boars and Pere David's rock squirrels were more active during the day. The relative abundance index of these mammals varied seasonally. Wild boars and Pere David's rock squirrels showed no obvious preference in elevation distribution, Reeves's muntjacs preferred low-elevation habitats (1,300 to 1,600 m), and golden takins mainly inhabited high-elevation areas (1,900 to 2,100 m). Golden takins showed obvious avoidance of roads, with avoidance distance from the road of >300 m. In contrast, Reeves's muntjacs were remarkably abundant within 200 m of the road. For both wild boars and Pere David's rock squirrels, there was no significant difference in RAI among 5 highway ranges. These findings help describe the distribution and activity patterns of these species in Qinling, to monitor their population dynamics, and to develop tailored conservation strategies for the 4 species and sympatric wildlife. [ABSTRACT FROM AUTHOR]

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

In response to the unclear rock properties of the formations in the Tazhong-Tabei block of the Tarim Basin and the difficulties in selecting drill bits, indoor rock drillability tests were conducted under high temperature and high-pressure conditions. The tests analyzed the changes in the drillability grade values of roller cone bits and PDC bits under the coupling effects of confining pressure and temperature. The research indicates that the drillability grade values of the rocks in this formation range between 4 and 6. Additionally, the drillability grade values of PDC bits are lower than those of roller cone bits. As confining pressure increases, the drillability grade values of the rocks also increase significantly when the confining pressure exceeds 30 MPa. Conversely, as the temperature rises, the drillability grade values of the rocks decrease substantially when the temperature exceeds 140 °C. A drillability analysis model for roller cone bits and PDC bits was established using finite element simulation software. The simulated drillability grade values of the rocks showed a discrepancy of less than 10% compared to the indoor test data, proving the accuracy and reliability of the indoor test data. Based on the rock drillability test results, the use of PDC bits is recommended for this formation. The optimized PDC bits successfully drilled through the target formation. These research findings are of guiding significance for accurately understanding the physical and mechanical properties of the formation rocks in the Tazhong-Tabei block and for the optimal selection of drill bits for this area. [ABSTRACT FROM AUTHOR]

New whole‐rock major and trace element geochemistry from the Leka Ophiolite Complex in Norway is presented and compared to the geochemical evolution and proposed tectonomagmatic processes recorded in the Izu‐Bonin‐Mariana system. These data demonstrate that the Leka Ophiolite Complex formed as forearc lithosphere during subduction initiation. A new high‐precision zircon U‐Pb date on forearc basalt constrains the timing of subduction initiation in the "Leka sector" of the Iapetus Ocean to 491.36 ± 0.17 Ma. The tectonomagmatic record of the Leka Ophiolite Complex captures only the earliest stages of subduction initiation and is thereby distinct from some other Appalachian–Caledonian ophiolites of similar age. The diversity of Appalachian–Caledonian ophiolite records may represent differing preservation and exposure of a variable forearc lithosphere. Plain Language Summary: The Leka Ophiolite Complex (LOC) represents a preserved fragment of oceanic crust that formed during subduction in the Iapetus Ocean. Geochemical information recorded in the LOC rocks shows that it formed during the initial phase of subduction. The age of subduction initiation in the Iapetus Ocean is estimated at 491.36 million years ago based on isotopic dating of minerals within the LOC rocks. Other fragments of preserved oceanic crust with similar ages are found in the Appalachian–Caledonian mountains; however, their geochemical information suggests that they may have formed during different stages of the subduction zone development. We consider the variations in the oceanic crustal record to reflect selective preservation of different parts of the variable oceanic crust formed during the development of a subduction zone in the Iapetus Ocean. Key Points: The Leka Ophiolite Complex (LOC) preserves a record of geochemical variation from forearc basaltic to boninitic magmatism, reflecting formation during initiation and early evolution of a subduction zoneA 491.36 ± 0.17 Ma U–Pb zircon date for an LOC forearc basalt is considered to date subduction initiation in the "Leka sector" of the Iapetus OceanDifferences between the LOC pseudostratigraphy and the model Izu‐Bonin‐Mariana forearc may result from selective preservation of the spatially variable forearc lithosphere in addition to the specific history of formation, obduction, deformation, and uplift/erosion records [ABSTRACT FROM AUTHOR]

The developing trend in tunnel engineering is toward the expansion of the tunnel's inner diameter, which is bound to affect the deformation of the tunnel surrounding rock. To address this problem, transient and slow unloading tests of small thick-walled cylindrical surrounding rock specimens made of natural sandstone with different inner diameters are performed. The influence of the tunnel excavation inner diameter on the deformation and failure characteristics of the surrounding rock under the two unloading rates is studied, and numerical simulations under the same conditions are performed using FLAC3D. The results show the following. (1) Under transient and slow unloading, the strain on the inside and outside of the surrounding rock specimen increases with increasing inner excavation diameter, and under the same conditions, the inner strain on the surrounding rock specimen is greater than the outer strain. (2) When the excavation diameter is small, the inner deformation of the surrounding rock specimen experiences partial rebound, and when the excavation diameter is large, the surrounding rock specimen is damaged. (3) The surrounding rock specimen shows obvious brittle characteristics when damaged. The specimens expand significantly along the radial direction, bulge and drop blocks in the direction of unloading, and are accompanied by circumferential cracks. (4) Comparison and analysis of the numerical simulation results with the test results indicate that the test values are 2–3 times larger than the numerical values but that the presented deformation laws are consistent. Highlights: Transient and slow unloading tests of thick-walled cylindrical surrounding rock specimens made of natural sandstone with different inner diameters were carried out using the self-developed roadway surrounding rock excavation unloading model test system. The deformation law of the tunnel surrounding rock with the increase of excavation diameter under different unloading rates was obtained. The characteristics of unloading failure of tunnel surrounding rock were monitored and observed. [ABSTRACT FROM AUTHOR]

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

The mode selectivity in the prototypical H + CH3D reaction is investigated by the initial state selected time-dependent wave packet method within a ten-dimensional quantum dynamics model. The model is a novel reduced dimensional model for the X + YCZ3 reaction, which allows the CZ3 to break C3V symmetry. The calculated reaction probabilities initially from different reactant vibrational states show that the CH3 stretching modes excitations obviously promote the H-abstraction reaction but have a slight influence on the D-abstraction reaction. In contrast, the CD stretching mode excitation significantly enhances the D-abstraction reaction. For both H- and D-abstraction reactions, the excitation of either the CH3 umbrella bending mode or the CH3 rocking mode shows a promotional effect on the reactivity, while fundamental excitation of the CH3 bending mode has a negligible effect. Impressively, the first-overtone excitation of CH3 bending mode remarkably promotes the H-abstraction reaction, resulting from the 1:2 Fermi coupling between the CH3 symmetric stretching mode and the first overtone of CH3 bending mode. In addition, translational energy is more efficient than vibrational energy in promoting the H-abstraction reaction at low energy, while vibrational energy becomes more efficient for the D-abstraction reaction. [ABSTRACT FROM AUTHOR]

In the field of rock engineering, the anisotropic failure criterion plays a vital role in predicting the strength of rocks with varying degrees of anisotropy. This study presents jointed rock as a composite material, encompassing both joints and rock blocks. A comprehensive model has been developed for jointed rock, introducing a new parameter denoted as η to account for the influence of joint thickness. Consequently, a predictive strength model that considers the thickness effect of joints has been formulated. Unlike Jaeger's single weak plane failure criterion, which exhibits a characteristic "U" shape, a novel functional model has been proposed. This new model explains the variation in strength concerning the angle of inclination. As a result, a new anisotropic strength criterion for jointed rocks has been developed. This criterion also provides a method for determining its parameters using Jaeger's failure theory. To validate the proposed criterion, 189 sets of test results from five distinct types of anisotropic rocks were utilized. The newly developed failure criterion aims to accurately estimate the anisotropic strength of jointed rocks. Moreover, it offers new criteria for evaluating the stability of engineering rock structures, particularly its applicability in predicting the strength of jointed or stratified rock mass exhibiting significant anisotropy. Highlights: A new rock strength empirical model considering the effect of joint thickness has been proposed, where the thickness and strength of joint surfaces have a significant impact on the overall strength. The overall strength of jointed rock mass shows a negative exponential decreasing trend with the increase of joint thickness. The larger the proportion of joint thickness, the closer the overall strength is to the strength of the joint surface. As the confining pressure increases, the anisotropy gradually weakens, and the confining pressure has an inhibitory effect on the anisotropy of the rock. A new empirical triaxial anisotropic failure criterion is proposed according to the variations of strength with θ and stress conditions. [ABSTRACT FROM AUTHOR]

Background: The use of rock powders in soil has emerged as a nature-based technology to improve soil properties relevant to crop development and for atmospheric carbon dioxide removal (CDR) via enhanced rock weathering (ERW). Although modeling this process is crucial, the soil microbiome has been identified as the main reason why several experimental and field results do not fit the geochemical and kinetic theoretical models. Here, the hypothesis that the bacterial community structure is modulated by the application of different silicate rock powders was tested. One phonolite, three basalt variations and one granite, as well as KCl treatments, were applied to a Ferralsol cultivated with Brachiaria in short-term pedogeochemical experiments and assessed after 1 (1M), 4 (4M) and 8 (8M) months. Results: The main changes in soil bacterial structure were observed at 8M and found to be modulated according to rock type, with petrochemistry and mineralogy acting as the main drivers. The content of microbial biomass carbon tended to decrease over time in the Control and KCl treatments, especially at 4M, while the rock treatments showed constant behavior. The sampling time and treatment affected the richness and diversity indices. The Si, Ca and Fe from mafic minerals were the main chemical elements related to the soil bacterial changes at 8M. Conclusions: The type (acidity) of silicate rock powder modulated the soil bacterial community (SBC) in a pot experiment with tropical soil. The specificity of the SBC for each rock type increased with time until the end of the experiment at 8 months (8M). The carbon content in the microbial biomass was lower in the rock powder treatments in the first month (1 M) than in the control and KCl treatments and was equal to or higher than that in the 8 M treatment. This result illustrates the challenge of modeling rock powder dissolution in soil since the soil medium is not inert but changes concurrently with the dissolution of the rock. [ABSTRACT FROM AUTHOR]

The pre-Liassic basement of the Biga Peninsula, located in the westernmost part of the Sakarya Zone, consists of metamorphic assemblages that were considered to represent different continental basements in the north and south, and the suture (ophiolitic/mélange) zone(s) between them. The Çetmi mélange, defined as between these continental fragments (the Kazdağ Massif in the south and the Çamlıca Massif in the north) was evaluated as a subduction accretionary mélange of the Intra-Pontide Ocean and it was assumed that a suture passed through this part of the peninsula. This study was carried out on the most widely distributed outcrops of the Çetmi mélange(?) on the northwest flank of the Kazdağ Massif. These units, which are named the Örenli metamorphics, are represented by a succession of low-grade metamorphic volcanic-volcaniclastic rocks and alternating metasedimentary rocks and recrystallized limestones. The tectonostratigraphically lowermost levels of the Örenli metamorphics are a blocky-chaotic assemblage, whereas the uppermost levels are a regular metavolcanic-metapelite succession, which passes upward into the Late Triassic recrystallized limestones, and is cut by very low-grade metamorphic diabase dykes of 165.81 ± 1.55 Ma age. Furthermore, metavolcanic rocks of this succession show a calc-alkaline association of Basalt-Andesite-Dacite-Rhyolite (BADR) pattern in the chemical classification diagram, which is the signature volcanic rock suite of convergent margins. In addition, all the metavolcanic rock samples show a significant enrichment in terms of incompatible elements and LIL elements and negative Nb and Ti anomalies on the MORB normalized multielement spider diagram, which indicates that these rocks characterize high-K calc-alkaline volcanism at the active continental margins. Field relationships, zircon U-Pb geochronology, and geochemical data support that these units, outcropping in the study area, represent a Triassic active continental margin, most probably a fore-arc setting, related to the Paleo-Tethyan subduction, but not the subduction mélange of the Intra-Pontide Ocean. [ABSTRACT FROM AUTHOR]

Acidification, as an effective measure to remove blockages and restore oil well productivity, has received widespread concern. However, conventional acid systems can only be used to unblock near‐wellbore zones and are difficult to act on far‐wellbore reservoirs. In this article, scanning electron microscope, energy‐dispersive X‐ray spectroscope, and X‐ray diffractometer were used to analyze the blockages in the Bai 823 well area, and it was determined that their main components were CaCO3 and FeCO3, which provided the basis for the construction of the unblocking formula. Then, the acid dissolution experiments on the plugging materials showed that the dissolution rate of 10% HCl can reach more than 85% for the scale sample; the acid dissolution experiments on the rock sample showed that the autogenous mud acid has better dissolution performance and better retardation performance for the rock sample, and the effective action time is longer, so it can be used for deeper unplugging of the reservoir. Finally, the process parameters such as the optimal acid concentration, acid dosage, and discharge volume were optimized by establishing the fracture‐matrix acid flow reaction model. Research results indicate that the autogenous mud acid can act on the blockage in the far‐wellbore area to improve the acidification effect. [ABSTRACT FROM AUTHOR]

In this study, we provide the first absolute ages for a Big Circle megalithic structure in Jordan, using rock surface luminescence dating of the buried surface of rocks collected from circle J4 in southern Jordan. Five rocks were used for this study. All rocks showed evidence of previous daylight exposure before being used in the construction of the circle. The exposure was sufficient to bleach the latent luminescence signal to a negligible level compared to the subsequent burial dose. Three rocks gave indistinguishable ages, and were last exposed to daylight in 1500 ± 100 BCE; this is very likely to be the date of circle construction. Two others gave younger ages, indicating later disturbance or reworking. These new results provide very strong evidence for construction during the Late Bronze Age, and refute the earlier hypothesis of construction during Umayyad period (661–750 CE) as a hunting trap. [ABSTRACT FROM AUTHOR]

The article titled "The Buford Highway Farmers Market" by Diamond Forde reflects on the author's memories of visiting the market with their family and the changes that occurred after a tragic event. The author describes the vibrant atmosphere of the market, with its diverse food offerings and friendly fishmonger. However, after a car accident, the author's grandmother's life became more isolated, with her only companionship being a television and religious programming. The author reflects on their promise to wear a leopard-print jacket that their grandmother bought but never got to see them wear. The article ends with the author finding joy and connection by wearing the jacket to a rock concert with their sister. Diamond Forde is an award-winning poet whose work has been published in various literary journals. [Extracted from the article]

Recent advancements in quantitatively estimating the thickness of Earth's crust in the geologic past provide an opportunity to test hypotheses explaining the tectonic evolution of southern Tibet. Outstanding debate on southern Tibet's Cenozoic geological evolution is complicated by poorly understood Mesozoic tectonics. We present new U‐Pb geochronology and trace element chemistry of detrital zircon from modern rivers draining the Gangdese Mountains in southern Tibet. Results are similar to recently published quantitative estimates of crustal thickness derived from intermediate‐composition whole rock records and show ~30 km of crustal thinning from 90 to 70 Ma followed by thickening to near‐modern values from 70 to 40 Ma. These results extend evidence of Late Cretaceous north–south extension along strike to the west by ~200 km, and support a tectonic model in which an east–west striking back‐arc basin formed along Eurasia's southern margin during slab rollback, prior to terminal collision of India with Eurasia. [ABSTRACT FROM AUTHOR]

Zircon from four plutons of peralkaline granites and quartz-bearing syenites, differing in geotectonic positions, petrological and mineralogical compositions, and contents of volatile and trace elements, was studied using SEM, CL, and EPMA with the intention to define typical textural and chemical features of zircon from peralkaline rocks. In strongly peralkaline Na-pyroxene-bearing rocks represented by the Khan Bogd and Khalzan Buregte plutons (Mongolia), the primary zircon is scarce or missing. Most zircon grains are secondary, originating in hydrothermal stage from primary Zr silicates. They often form globular or radial aggregates. Chemical compositions of zircon in these rocks typically show high contents of Y, moderate contents of REE (thus high Y/Yb values) together with low contents of U and Th and low analytical totals. In mildly peralkaline mica-bearing rocks represented by Ivigtut stock (Groenland) and Madeira pluton (Brazil), the exclusive primary Zr mineral is zircon, mostly of orthomagmatic origin. Its analytical totals approach 100 wt%, enrichment in HREE, resulting in low Y/Yb values, is typical. Zircon populations from two types of peralkaline granitoids can be distinguished from each other and from zircon from S-type granites based on combination of the Zr/Hf, Y/Yb, and U/Th values, or on the Y-Hf-P ternary diagram. [ABSTRACT FROM AUTHOR]

Understanding joints is becoming increasingly important in South Korea owing to the development of plans for high-level waste disposal. This study examined drill cores to assess the morphology of joints in five areas with different rock types. The depths and dip angles of 14,169 joints were measured, and the joints were then classified based on their dip angles. Joint spacings within each set were statistically analyzed and fitted to five statistical distribution models: double Weibull, exponential, generalized log-logistic, gamma, and lognormal. Results for each given type of rock showed similar dip angles but varying depths. The observed joint spacings were most accurately fitted using the lognormal distribution. The results of this study will provide insights into the distributions of joints in South Korea and can be used in numerical modeling and stability assessments. [ABSTRACT FROM AUTHOR]

China's coal mines are mainly underground mines, and a large number of roadways have to be excavated underground. It is of great significance for coal mine production to adopt safe and reasonable roadway support methods. In the process of roadway excavation, the rock stratum is inclined and the roadway pass through the layer. Since the surrounding rock conditions of the roadway passing through the layer are more complicated, it is easy to cause deformation of surrounding rock, failure and floor heave, which makes the support work difficult. In order to solve this problem, the mechanical properties of roadway surrounding rock were tested and the failure of roadway surrounding rock was analyzed using the +260 horizontal centralized transportation roadway in Changcheng No.2 mine. The surrounding rock of the roadway was divided into 8 regions, and the stress analysis of the surrounding rock in different regions was carried out. It is found that the left shoulder pit, the right side and the floor of the roadway are prone to damage. The influence of the lateral pressure coefficient, the rock dip angle and the lithology on the failure of the roadway surrounding rock was analyzed by Mohr-Coulomb failure criterion, and the specific failure range of the roadway surrounding rock was obtained. The support optimization design of the roadway was carried out, and the weak area of the surrounding rock was reinforced. The deformation monitoring of roadway surrounding rock after support optimization was carried out. The field monitoring results show that after the optimized support, the displacement of the roof and floor of the roadway section and the two sides are reduced by 43.6% and 40.8% respectively compared with the original scheme, and the deformation of the surrounding rock also shows a trend of gradual stability, and the surrounding rock of the roadway is effectively controlled. The research can provide a new way for the stress and failure analysis of the surrounding rock of the inclined rock roadway. [ABSTRACT FROM AUTHOR]

Rho‐associated coiled‐coil kinases (ROCKs) are key downstream effectors of small GTPases. ROCK plays a central role in diverse cellular events with accumulating evidence supporting the concept that ROCK is important in tumor development and progression. Numerous ROCK inhibitors have been investigated for their therapeutic potential in the treatment of cancers. In this article, we review recent research progress on ROCK inhibitors, especially those with potential for the treatment of cancers, reported in the literature from 2015 to 2021. Most ROCK inhibitors show potent in vitro and in vivo antitumor activities and have potential in the treatment of cancers. [ABSTRACT FROM AUTHOR]

High‐voltage electric pulse drilling technology has the advantages of high rock‐breaking efficiency, low energy consumption for rock breaking, and good quality of well wall, which is a new and efficient potential rock‐breaking method. In this paper, we constructed a numerical simulation model of rock electric breakdown and realized the whole process of rock breaking and plasma channel generation by high‐voltage electric pulse. The results of the study showed that the change of magnetic field has a large influence on the formation of plasma channels inside the rock, and under the self‐magnetic field environment, the plasma channels inside the rock show branching, and the maximum penetration depth and maximum damage depth are higher than those under the non‐magnetic field environment. In the external magnetic field environment, the plasma channels gradually tend to develop "downward" (inside the rock), and the temperature distribution of the plasma channels inside the rock is more concentrated. In the presence of a magnetic field, the speed and degree of freedom of charged particles are limited. In an external magnetic field environment, the charged particles cause fewer particles to deviate, and the particles show a "downward" accumulation phenomenon. The research in this paper can provide certain theoretical and technical guidance for the development of electric pulse rock‐breaking technology and provide reference for the development and parameter optimization of electric pulse rock‐breaking tools. [ABSTRACT FROM AUTHOR]

Ronald James Padovana was born 10 July 1942. In 1957 he began what became a fifty threeyear career in music career. In 1960 he began singing under the name Ronnie Dio, and then Ronnie James Dio. Under this name he became an iconic hard rock vocalist, performing with numerous bands including Rainbow (1974-1979), Black Sabbath (1979-1982, 1992, and 2006-2010), and his own band Dio (1982-2004). Before his untimely death on 16 May 2010, he had performed 2293 shows in 627 cities in forty-eight countries around the world. He sold over 6,500,000 albums. This map shows every city he performed in during his career at a scale of 1:74,380,000, along with three insets at varying scales highlighting performances within different world regions, and a series of 28 separate inset maps at a scale of 1:575,000,000 showing the cities he performed in during each concert tour. [ABSTRACT FROM AUTHOR]

The Ijero-Ekiti tourmaline-bearing pegmatite was investigated, using geological, geochemical, and geophysical methods to characterize its geological evolution and evaluate its mineralisation potential. Petrographical studies revealed a typical granitic mineralogical composition of quartz, feldspar, and muscovite, with tourmaline as accessory minerals. Geochemical data on whole rock analysis showed high and moderate enrichments in SiO2 (av. 71.65 wt. %) and Al2O3 (av. 14.71 wt. %) respectively, while mean values for the other major oxides ranged between 0.01 and 3.63 wt. %. Results also showed that K2O (av. 3.63 wt. %) and Na2O (av. 3.52 wt. %) concentrations were comparable to average Upper Continental values. The relatively high aluminum and alkaline compositions could be attributed to pneumatolytic crystallization from the pegmatitic melt. Aluminum Saturation Index (ASI) [Al/(Ca+Na+K)] indicated peraluminous character. Ranges of some trace elements (Cs, 1.5 - 705.6 ppm; Be, 0.5 - 12 ppm; Sn, 2.0 - 34 ppm; Ta, 1.0 - 14) support a Lithium-Cesium-Tantalum (LCT) type rare-elements pegmatites for the pegmatites of the study. The spider and K/Rb vs K/Cs plots portrayed fractionation trends suggestive of potential mineralisation. The vertical electric sounding data showed that pegmatites underlie the lateritic zone and represent the anomalous layer characterized by high resistivity values ranging from 1086 to 9489 Ohm-m with the surface to a maximum depth of 20.8m which is suspected to be a mineralised zone. Some of these pegmatites are highly tourmalinated, suggesting that they emanate from highly mineralised magma and are believed to represent late-stage pneumatolytic fluids derived from acidic magma bodies through magmatogenic processes. [ABSTRACT FROM AUTHOR]

Understanding the mechanical properties of rock is of great significance for the development of unconventional reservoirs. However, a large number of bedding makes the mechanical laws of rock unclear. To investigate the effect of bedding properties on the uniaxial mechanical properties of rock, the coal model containing bedding is developed based on the continuous–discontinuous method, and the effect of bedding angle, bedding strength, bedding number, and loading rate on the uniaxial mechanical properties of rock is investigated. The failure morphology, stress–strain evolution, peak stress, and fracture degrees are analyzed and discussed in detail. The reliability of the numerical model in this paper has been verified by comparison with the indoor experiments. The results show that when the bedding angle is 0°, the peak stress of the rock is maximum, 8.16 MPa, and when the bedding angle is 90°, the fracture degree of the rock is maximum, 3.74%. For the different bedding strengths, the peak stress first decreases linearly with the decrease of the bedding strength. The peak stress barely varies when the bedding strength is less than 0.5 MPa. The fracture degree of the rock shows a nonlinear increase with the increase in bedding strength. For different bedding numbers, the activation of the bedding is not related to the bedding number. The loading speed also has a great influence on the mechanical properties of rock. With the increase in loading rate, the difficulty of bedding activation gradually increases, and the complexity of fractures gradually increases. This study aims to further improve the understanding of the effect of bedding properties on the uniaxial mechanical properties of rock. [ABSTRACT FROM AUTHOR]

In rock masses, there might be structural nonstationarity in the joint morphology that influences the shear behavior of rock joints. However, research into this effect is seldom reported. In this study, shear tests on artificial rock joints that contained stationary morphology and different nonstationary features were conducted. The experimental results showed that nonstationarity has a significant effect on the shear properties of rock joints. Under the action of lower normal stress levels, the peak shear strength of joints increased with the increase in the nonstationary angle, and it was easy for the slip behavior along the nonstationary trend to occur. Under higher normal stress levels, the damage to big areas in the upper and lower joint blocks, especially on the left and right ends of the joint surfaces, readily appeared. In this case, the nonstationary characteristics tended to be the main factor that controlled the damage to joints. The analysis revealed that after subtracting the nonstationary angle, the peak friction angles of the joints with nonstationarity were close to the peak friction angles of the joints with stationary morphology and provided the same normal stress. Therefore, the nonstationary angle and stationary joint morphology were separately but fully considered to describe the peak dilatancy angle. Using the proposed model for the peak dilatancy angle, a new criterion for the peak shear strength of joints that contained nonstationary features was established. Comparisons of the new criterion with the published criteria when estimating the peak shear strength of rough rock joints showed that the new criterion has a good prediction accuracy for rock joints with nonstationarity. [ABSTRACT FROM AUTHOR]

To study the stress distribution characteristics of the surrounding rock of the gob-side coal–rock roadway in a gently inclined coal seam under the influence of excavation and mining disturbance, a physically similar simulation experiment was carried out. With an infrared thermal imager and professional infrared thermal analysis software (SmartView 4.3), the 2D and 3D temperature fields of the detection object were obtained, the numerical simulations were conducted, and the stress state of the surrounding rock was indirectly analyzed. The results indicated that during the excavation disturbance stage, the stress mainly occurred at the coal pillar side. When the coal pillar widths gradually decreased from 10 to 3 m, the stress monitoring value of the surrounding rock showed that the change process was "rising, decreasing, then rising again," and the increase of the stress level of the surrounding rock was the greatest when the width was 8 m. With the increase of mining disturbance intensity, the coal pillar yielded instability gradually, and the stress concentration area of the surrounding rock gradually shifted from the initial coal pillar side to the lower solid coal side. Under the influence of excavation and mining disturbance, the range of relatively high or low temperatures of the surrounding rock was basically consistent with the large and small area distribution of the stress monitoring value during the surrounding rock stress concentration and transfer. This showed that the method of indirect analysis of the surrounding rock stress state based on infrared temperature detection was highly feasible. The numerical simulation results showed that under the influence of excavation and mining disturbance, the stress distribution of the surrounding rock was basically consistent with the infrared temperature field detection results during the surrounding rock stress concentration and transfer. Our research conclusions provide a scientific basis and theoretical guidance for the deformation mechanism and control technology of the surrounding rock of gob-side coal–rock roadways in a gently inclined coal seam. [ABSTRACT FROM AUTHOR]

Tight gas sandstone reservoirs are commonly characterized by complex diagenetic processes, resulting in time-consuming analysis for manual classification and prediction of diagenetic facies types with inherent preference and accuracy limitations. This work explores the feasibility of automatically classifying and predicting diagenetic facies types in tight gas sandstone reservoirs using unsupervised and supervised machine learning models. Firstly, petrophysical and petrological parameters, including porosity, permeability, bulk density, cement content, plane porosity, intergranular volume, and dissolution pore volume were used as input to identify diagenetic facies types automatically through an unsupervised machine learning model based on K-means algorithm. The classified diagenetic facies types exhibited significant diagenetic differences as shown in rock thin sections. Subsequently, with the identified diagenetic facies type as the learning target and logging series data as input, three types of supervised machine learning models were employed to predict the single-well vertical profile of diagenetic facies type distribution. The results indicated that the XGBoost model had optimal performance with the accuracy of 0.87. This work provides a complete automated workflow from basic petrophysical data to complex diagenetic facies profiles based on supervised and unsupervised machine learning models for diagenetic facies type analysis. [ABSTRACT FROM AUTHOR]

As the depth of mineral exploration increases, integrated geophysical methods are increasingly playing a crucial role in prospecting deep structures at the district scale. The Nanling-Xuancheng ore district is the eighth ore district in the middle-lower Yangtze metallogenic belt in China. To reveal the deep structure of the mining district, this study mainly focuses on regional high-precision gravity and magnetic data and integrates the interpretation of magnetotelluric and reflection seismic data from a key area. By using a 2.5D joint inversion method with prior information constraints, new insights into the deep structures, tectonic deformation, and magmatic activity are obtained. Structurally, the Nanling-Xuancheng ore district presents a structural pattern of "two uplifts and two depressions" composed of multi-level thrust-overturned and folds formed by Mesozoic depressions, which has a three-layer structure in the vertical direction (shallower than 10 km). Tectonically, the main faults in the study area trend NW, which intersect with NE-trending and EW-trending faults to form a branching structure from deep to shallow. The fault intersections provide pathways for magma intrusion. The distribution of deep-seated concealed magmatic rocks shows the characteristic pattern of "a primary magma source spawning multiple subsidiary intrusion". [ABSTRACT FROM AUTHOR]