Journal articles: 'Rocks'

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Noma, Kensuke, Naotsugu Oyama, and James K. Liao. "Physiological role of ROCKs in the cardiovascular system." American Journal of Physiology-Cell Physiology 290, no. 3 (March 2006): C661—C668. http://dx.doi.org/10.1152/ajpcell.00459.2005.

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Rho-associated kinases (ROCKs), the immediate downstream targets of RhoA, are ubiquitously expressed serine-threonine protein kinases that are involved in diverse cellular functions, including smooth muscle contraction, actin cytoskeleton organization, cell adhesion and motility, and gene expression. Recent studies have shown that ROCKs may play a pivotal role in cardiovascular diseases such as vasospastic angina, ischemic stroke, and heart failure. Indeed, inhibition of ROCKs by statins or other selective inhibitors leads to the upregulation and activation of endothelial nitric oxide synthase (eNOS) and reduction of vascular inflammation and atherosclerosis. Thus inhibition of ROCKs may contribute to some of the cholesterol-independent beneficial effects of statin therapy. Currently, two ROCK isoforms have been identified, ROCK1 and ROCK2. Because ROCK inhibitors are nonselective with respect to ROCK1 and ROCK2 and also, in some cases, may be nonspecific with respect to other ROCK-related kinases such as myristolated alanine-rich C kinase substrate (MARCKS), protein kinase A, and protein kinase C, the precise role of ROCKs in cardiovascular disease remains unknown. However, with the recent development of ROCK1- and ROCK2-knockout mice, further dissection of ROCK signaling pathways is now possible. Herein we review what is known about the physiological role of ROCKs in the cardiovascular system and speculate about how inhibition of ROCKs could provide cardiovascular benefits.

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Zhang, Jin Yu, Huan Sheng Dong, Reza K. Oqani, Tao Lin, Jung Won Kang, and Dong Il Jin. "Distinct roles of ROCK1 and ROCK2 during development of porcine preimplantation embryos." REPRODUCTION 148, no. 1 (July 2014): 99–107. http://dx.doi.org/10.1530/rep-13-0556.

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Cell-to-cell contact mediated by cell adhesion is fundamental to the compaction process that ensures blastocyst quality during embryonic development. In this study, we first showed that Rho-associated coiled-coil protein kinases (ROCK1 and ROCK2) were expressed both in porcine oocytes and IVF preimplantation embryos, playing different roles in oocytes maturation and embryo development. The amount of mRNA encoding ROCK1 and the protein concentration clearly increased between the eight-cell and morula stages, but decreased significantly when blastocysts were formed. Conversely, ROCK2 was more abundant in the blastocyst compared with other embryonic stages. Moreover, immunostaining showed that ROCK1 protein distribution changed as the embryo progressed through cleavage and compaction to the morula stage. Initially, the protein was predominantly associated with the plasma membrane but later became cytoplasmic. By contrast, ROCK2 protein was localized in both the cytoplasm and the spindle rotation region during oocyte meiosis, but in the cytoplasm and nucleus as the embryo developed. In addition, ROCK2 was present in the trophectoderm cells of the blastocyst. Treatment with 15 μM Y27632, a specific inhibitor of ROCKs, completely blocked further development of early four-cell stage embryos. Moreover, we did not detect the expression ofROCK1but did detectROCK2expression in blastocysts. Moreover, lysophosphatidic acid an activator of ROCKs significantly improved the rates of blastocyst formation. These data demonstrate that ROCKs are required for embryo development to the blastocyst stage. Together, our results indicate that ROCK1 and ROCK2 may exert different biological functions during the regulation of compaction and in ensuring development of porcine preimplantation embryos to the blastocyst stage.

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Haga, Raquel B., Ritu Garg, Francesca Collu, Bárbara Borda D'Agua, Sofia T. Menéndez, Audrey Colomba, Franca Fraternali, and Anne J. Ridley. "RhoBTB1 interacts with ROCKs and inhibits invasion." Biochemical Journal 476, no. 17 (September 13, 2019): 2499–514. http://dx.doi.org/10.1042/bcj20190203.

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Abstract RhoBTB1 is an atypical Rho GTPase with two BTB domains in addition to its Rho domain. Although most Rho GTPases regulate actin cytoskeletal dynamics, RhoBTB1 is not known to affect cell shape or motility. We report that RhoBTB1 depletion increases prostate cancer cell invasion and induces elongation in Matrigel, a phenotype similar to that induced by depletion of ROCK1 and ROCK2. We demonstrate that RhoBTB1 associates with ROCK1 and ROCK2 and its association with ROCK1 is via its Rho domain. The Rho domain binds to the coiled-coil region of ROCK1 close to its kinase domain. We identify two amino acids within the Rho domain that alter RhoBTB1 association with ROCK1. RhoBTB1 is a substrate for ROCK1, and mutation of putative phosphorylation sites reduces its association with Cullin3, a scaffold for ubiquitin ligases. We propose that RhoBTB1 suppresses cancer cell invasion through interacting with ROCKs, which in turn regulate its association with Cullin3. Via Cullin3, RhoBTB1 has the potential to affect protein degradation.

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Priya, Rashmi, Xuan Liang, Jessica L. Teo, Kinga Duszyc, Alpha S. Yap, and Guillermo A. Gomez. "ROCK1 but not ROCK2 contributes to RhoA signaling and NMIIA-mediated contractility at the epithelial zonula adherens." Molecular Biology of the Cell 28, no. 1 (January 2017): 12–20. http://dx.doi.org/10.1091/mbc.e16-04-0262.

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Rho kinases (ROCK1 and ROCK2) function downstream of the small GTPase RhoA to drive actomyosin cytoskeletal remodeling. It has often been believed that ROCK1 and ROCK2 may be functionally redundant, as they share a highly conserved kinase domain. However, in this study, we report differential functional effects for these ROCKs at the epithelial zonula adherens (ZA). Using specific siRNA, we found that ROCK1 depletion disrupted cadherin organization at the ZA, accompanied by loss of F-actin and NMIIA, whereas ROCK2 knockdown had no significant effect. Further, ROCK1, but not ROCK2, was necessary to stabilize GTP-RhoA at the ZA, thereby sustaining junctional tension and inhibiting intraepithelial cell movement. We also found that nonmuscle myosin IIA is a major determinant of ROCK1 cortical stability. Thus, despite sharing the catalytic domain with ROCK2, ROCK1 appears to be the dominant kinase essential for junctional integrity and contractile tension at epithelial ZA.

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Kitchenham, Paul. "Rock Art: “Tatooing” Rocks?" Time and Mind 2, no. 3 (January 2009): 347–48. http://dx.doi.org/10.2752/175169609x12464529903254.

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Fernández, F. J., and S. Llana-Fúnez. "Deformación asociada a la falla de Valdoviño (Noroeste del Macizo Ibérico) Deformation related to the Valdoviño fault (Northwest Iberian Massif)." Trabajos de Geología 36, no. 36 (September 12, 2018): 95. http://dx.doi.org/10.17811/tdg.36.2016.95-118.

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Resumen: La sección costera de la falla de Valdoviño expone rocas de falla deformadas en las proximidades de la base de la zona sismogénica de la corteza Ibérica Varisca, en la que estructuras frágiles discretas afectan una zona de deformación predominantemente dúctil. El núcleo de la falla contiene rocas ultramáficas, rocas máficas con granate, anfibolitas, neises cuarzo-feldespáticos y metavulcanitas básicas entre las facies deformadas del granitoide Varisco de A Espenuca. Este artículo describe la deformación y microestructuras relacionadas con la falla desarrolladas en el granitoides. La composición y características tectonometamórficas del resto de rocas presentes en el núcleo de la falla sugieren que las estructuras asociadas a la falla se superpusieron a fábricas tectónicas previas, similares a las que presentan las rocas de los complejos alóctonos del NO del Macizo Ibérico.Palabras clave: microestructura, rocas de falla, corteza continental, EBSD, Orógeno Varisco.Abstract: The coastal section across the Valdoviño fault exposes fault-related rocks deformed at the base of the seismogenic zone of the Iberian Variscan crust. Discrete brittle structures are superimposed over previous predominant ductile deformation fabrics in most rocks. The core of the fault contains ultramafic rocks, garnet-bearing mafic rocks, amphibolites, quartzo-feldspathic gneisses and basic metavulcanites, in between the deformed facies of the A Espenuca Variscan granitoid. We show the deformation and microstructures related to the fault developed in the Variscan granitoid. The composition and tectonometamorphic features of the rest of the related rocks at the core of the fault suggest that deformation structures are superposed onto earlier tectonic fabrics, similar to those present in the rocks of the allochthonous complexes of the NW Iberian Massif.Keywords: microstructure, fault-related rocks, continental crust, SEM-EBSD, Variscan Orogeny.

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Leckie, Dale. "Petrology and tectonic significance of Gates Formation (early Cretaceous) sediments in northeast British Columbia." Canadian Journal of Earth Sciences 23, no. 2 (February 1, 1986): 129–41. http://dx.doi.org/10.1139/e86-017.

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Moosebar–Gates sandstones are predominantly litharenites, with some feldspathic litharenites. Both the light- and heavy-mineral suites indicate a mixed source characterized by clastic and carbonate sedimentary rocks, acidic to intermediate plutonic and volcanic igneous rocks, and metamorphic rocks. The sediment sources all fall within a recycled orogenic provenance grouping. Histograms showing stratigraphic variation of mineral content do not indicate any significant progressive unroofing of more deeply buried source rocks.The source area was very extensive regionally and extended well into the Omineca Crystalline Belt and eastern margins of the Intermontane Belt. Zebraic chalcedony was derived from evaporitic rocks of the Charlie Lake Formation, situated east of the Rocky Mountain Trench. Kyanite and almandine garnet were probably derived from the Omineca Crystalline Belt west of the Rocky Mountain Trench. Regional paleoslope dipped towards the north-northwest. Restoration of strike-slip on the Rocky Mountain Trench places potential source areas to the south of the depocentre; this supports paleoslope data. During Moosebar–Gates time the Tenakihi Group in the Omineca Crystalline Belt would have been hundreds of kilometres south of its present location and south of the study area, where it could have provided sediment. Volcanic rocks were derived from west of the Rocky Mountain Trench. Source rocks in the Omineca Crystalline Belt were being eroded as early as late early Albian and providing sediment into the foreland basin to the east.

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Kravchuk, Yaroslav, Roman Hnatiuk, Myroslav Ivanyk, and Yaroslav Khomyn. "General features of relief of Marmaroshi and Pieniny rocks of Ukrainian Carpathians and their place under system of geomorphological regionalization." Visnyk of the Lviv University. Series Geography, no. 42 (October 15, 2013): 204–20. http://dx.doi.org/10.30970/vgg.2013.42.1860.

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Peculiarities of geological structure and relief of Ukrainian fragment of zones of Marmaroshi and Pieniny rocks located between Outer (Flysch) and Inner Carpathians are considered. Morphostructural differences and common features of relief of these zones are clarified. Territory of zones of Marmaroshi and Pieniny rocks is considered as separate geomorphological region of mountain part of Ukrainian Carpathians – subregion of Intermountain Valleys and Rocky Chains. Expediency of separation and taxonomic class of this geomorphological region are proved, its division into taxonomic units of lower class is realized. Key words: Marmaroshi rocks, Pieniny rocks, klippes (limestone rocks of Jurassic period), morphostructure, geomorphological regionalization, Ukrainian Carpathians.

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Rahmawan, S., S. Irham, A. Nugrahanti, F. Herdiansyah, Samsol, S. Prakoso, M. Burhannudinnur, et al. "Carbonate Rocks Grouping Using Critical Porosity Approach in Miocene Rocks, Banggai Basin." IOP Conference Series: Earth and Environmental Science 1451, no. 1 (February 1, 2025): 012011. https://doi.org/10.1088/1755-1315/1451/1/012011.

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Abstract Reservoir is the trapped location of hydrocarbons with diverse physical rock properties or high heterogeneity. The characteristics of rock heterogeneity significantly influence the rock’s ability to flow fluids, especially hydrocarbons contained within the reservoir rock. Several methods have been developed to classify the heterogeneity of reservoir rocks, such as the Amaful, Wibowo and Permadi methods, among others. These methods are developed based on experiments using sandstone rocks, although in some studies, they are also frequently employed in categorizing carbonate reservoir rocks. However, these commonly used methods still face challenges in rock classification when actual rock samples are unavailable. In this study, the classification of carbonate reservoir rocks is conducted using a critical porosity approach compared to the classification using the Wibowo and Permadi methods, as well as the hydraulic flow unit method employed in previous research. The data utilized in this study consists of experimental 43 rock samples from the Miocene era of the Banggai Basin. The analysis results reveal that using the Wibowo and Permadi method, 10 rock classifications are obtained, whereas employing the critical porosity approach results in 6 rock groups. Both methods demonstrate a correlation between rock pore structure and rock geometry, where rocks categorized under RT-10 in the Wibowo and Permadi method and RT-6 in the critical porosity method exhibit the smallest pore geometry values compared to other rock groups. Each rock classification signifies the rock’s fluid flow capability, with rocks categorized under RT-1 indicating better fluid flow capability as they possess finer geometries.

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Xie, Busheng, Lixin Wu, Wenfei Mao, Shengyu Zhou, and Shanjun Liu. "An Open Integrated Rock Spectral Library (RockSL) for a Global Sharing and Matching Service." Minerals 12, no. 2 (January 20, 2022): 118. http://dx.doi.org/10.3390/min12020118.

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Minerals and rocks are important natural resources that are formed over a long period of geological history. Spectroscopy is the basis of the identification and characterisation of rocks and minerals via proximal sensing in the field or remote sensing systems with multi- and hyper-spectral capabilities. However, spectral data is scattered around different institutions worldwide and stored in various formats, resulting in poor data usability and an unnecessary waste of time and information. To improve the usability and performance of mineral spectral data, we developed an integrated open mineral spectral library (Rock Spectral Library, RockSL). Shared spectral data and related information were collected worldwide, and data cleaning measures were performed to retain the qualified spectra and merge all qualified data (raster, vector, and text formats) in a common framework to establish a reliable and comprehensive digital data set for an easy sharing and matching service. A software system was developed for the RockSL to manage, analyse, and apply the spectral data of minerals and rocks. We demonstrate how the information encoded in RockSL can determine the species of unknown rocks and describe specific mineral compositions. We also provide a reference scheme of the work chain and present key technologies for building different spectral libraries in diverse fields using RockSL. New contributions to RockSL are encouraged for this work to be improved to provide a better service and extend the applications of geo-sciences. This article introduces the characteristics of RockSL and demonstrates an experimental application.

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Henderson, Benjamin W., Kelsey M. Greathouse, Raksha Ramdas, Courtney K. Walker, Tejeshwar C. Rao, Svitlana V. Bach, Kendall A. Curtis, Jeremy J. Day, Alexa L. Mattheyses та Jeremy H. Herskowitz. "Pharmacologic inhibition of LIMK1 provides dendritic spine resilience against β-amyloid". Science Signaling 12, № 587 (25 червня 2019): eaaw9318. http://dx.doi.org/10.1126/scisignal.aaw9318.

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Alzheimer’s disease (AD) therapies predominantly focus on β-amyloid (Aβ), but Aβ effects may be maximal before clinical symptoms appear. Downstream of Aβ, dendritic spine loss correlates most strongly with cognitive decline in AD. Rho-associated kinases (ROCK1 and ROCK2) regulate the actin cytoskeleton, and ROCK1 and ROCK2 protein abundances are increased in early AD. Here, we found that the increased abundance of ROCK1 in cultured primary rat hippocampal neurons reduced dendritic spine length through a myosin-based pathway, whereas the increased abundance of ROCK2 induced spine loss through the serine and threonine kinase LIMK1. Aβ42 oligomers can activate ROCKs. Here, using static imaging studies combined with multielectrode array analyses, we found that the ROCK2-LIMK1 pathway mediated Aβ42-induced spine degeneration and neuronal hyperexcitability. Live-cell microscopy revealed that pharmacologic inhibition of LIMK1 rendered dendritic spines resilient to Aβ42 oligomers. Treatment of hAPP mice with a LIMK1 inhibitor rescued Aβ-induced hippocampal spine loss and morphologic aberrations. Our data suggest that therapeutically targeting LIMK1 may provide dendritic spine resilience to Aβ and therefore may benefit cognitively normal patients that are at high risk for developing dementia.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips: How Should Rocks Be Labeled?" Rocks & Minerals 63, no. 5 (September 1988): 407. http://dx.doi.org/10.1080/00357529.1988.11761873.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips: Are There Rocks That Bend?" Rocks & Minerals 67, no. 3 (June 1992): 194–98. http://dx.doi.org/10.1080/00357529.1992.9926483.

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Surya Adinatha, Made Surya, and Ni Putu Tisna Andayani. "Music Creation Wajaprani | Tabuh Kreasi Wajaprani." GHURNITA: Jurnal Seni Karawitan 4, no. 2 (June 7, 2024): 219–26. http://dx.doi.org/10.59997/jurnalsenikarawitan.v4i2.3409.

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Coral rocks, as an iconic element of Bali's coast, have a central role in the island's art and culture. Music, musical arts and dance in Bali often use the character and unique shapes of coral rocks found along the coast to become inspiration for works of art. In Jembrana district, precisely in Pengeragoan village, there is Yeh Leh Beach, on this beach there are beautiful coral rocks which later became the inspiration for the creation of the creative percussion work entitled Wajaprani. The rock's sturdy character even when hit by waves is an inspiration for creating dynamic rhythms. with the character of the coral rocks on Yeh Leh Beach, the stylist thought it would be very suitable to use the medium of gamelan gong kebyar to implement the characters on the coral rocks.

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Md., Fahim Abrar Hossain, Tasneem Nazeefa, B. M. Rashed Alam A, and S. M. Fahad Hossain A. "Study on the Properties and Uses of Rocks Found in Bangladesh." Journal of Earthquake Science and Soil Dynamics Engineering 3, no. 3 (December 28, 2020): 1–7. https://doi.org/10.5281/zenodo.4395346.

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A rock is a natural substance made up of solid crystals of various minerals that were fused into a solid lump together. The solid mineral material that is part of the earth's surface and other similar planets that is exposed on the surface or underlying the earth. There are three main rock groups: Igneous rocks, Sedimentary rocks, and Metamorphic rocks. Rocks are of great resource value like minerals, some directly, and some as mineral constituents. Nearly all types of building materials used to pave roads, floors, and house walls, or various other structures, including bridges, come from rocks. These rocks are found in countries all over the world. In this research, different rocks that are found in Bangladesh were collected and identified depending on their color, texture and grain size. This paper also deals with the properties and uses of these rocks.

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Lavrskaya, Ekaterina A., Aleksey E. Selivanov, and Ksenia O. Pechenkina. "Representatives of the family Teloschistaceae as a component of the vegetation cover of rocky outcrops in the Chusovaya River valley (Middle Urals)." Вестник Пермского университета. Серия «Биология»=Bulletin of Perm University. Biology, no. 3 (2024): 263–68. http://dx.doi.org/10.17072/1994-9952-2024-3-263-268.

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The paper presents data on the patterns of lichens of the family Teloschistaceae on coastal rocks in the middle reaches of the Chusovaya River from the village of Kyn to the town of Chusovoy (Perm Krai, Sverdlovsk Oblast). To describe the lichen cover on rocky outcrops, 30×30 cm survey plots were laid out. Each site was photographed with a scale ruler, and habitat characteristics such as surface slope, exposure, overhangs, and rock were recorded. The family Teloschistaceae in the study area on rocky outcrops is represented by three genera: Caloplaca, Rusavskia, and Xanthoria. Of these genera, Rusavskia has the highest occurrence and projective coverage. Maximum indicators of occurrence of representatives of the family are noted on limestone rocks. On rocks from other rocks (sandstones) they occur less frequently. Teloschistaceae show higher values of projective coverage and occurrence on southern and eastern exposures. Representatives of Teloschistaceae are among the dominant species that play an important role in the lichen cover of coastal rock outcrops. The main factors determining their distribution on the studied substrates are exposure, rock type, and relief character.

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Satoh, Kimio, Yoshihiro Fukumoto, and Hiroaki Shimokawa. "Rho-kinase: important new therapeutic target in cardiovascular diseases." American Journal of Physiology-Heart and Circulatory Physiology 301, no. 2 (August 2011): H287—H296. http://dx.doi.org/10.1152/ajpheart.00327.2011.

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Rho-kinase (ROCKs) belongs to the family of serine/threonine kinases and is an important downstream effector of the small GTP-binding protein RhoA. There are two isoforms of Rho-kinase, ROCK1 and ROCK2, and they have different functions with ROCK1 for circulating inflammatory cells and ROCK2 for vascular smooth muscle cells. It has been demonstrated that the RhoA/Rho-kinase pathway plays an important role in various fundamental cellular functions, including contraction, motility, proliferation, and apoptosis, leading to the development of cardiovascular disease. The important role of Rho-kinase in vivo has been demonstrated in the pathogenesis of vasospasm, arteriosclerosis, ischemia-reperfusion injury, hypertension, pulmonary hypertension, stroke, and heart failure. Furthermore, the beneficial effects of fasudil, a selective Rho-kinase inhibitor, have been demonstrated for the treatment of several cardiovascular diseases in humans. Thus the Rho-kinase pathway is an important new therapeutic target in cardiovascular medicine.

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Doyle, Alexandra E., Beth Klein, Ben Zuckerman, Hilke E. Schlichting, and Edward D. Young. "Exoplanetary oxygen fugacities from polluted white dwarf stars." Proceedings of the International Astronomical Union 15, S357 (October 2019): 28–32. http://dx.doi.org/10.1017/s1743921320000939.

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AbstractThe intrinsic oxygen fugacity of a planet profoundly influences a variety of its geochemical and geophysical aspects. Most rocky bodies in our solar system formed with oxygen fugacities approximately five orders of magnitude higher than that corresponding to a hydrogen-rich gas of solar composition. Here we derive oxygen fugacities of extrasolar rocky bodies from the elemental abundances in 15 white dwarf (WD) stars polluted by accretion of rocks. We find that the intrinsic oxygen fugacities of rocks accreted by the WDs are similar to those of terrestrial planets and asteroids in our solar system. This result suggests that at least some rocky exoplanets are geophysically and geochemically similar to Earth.

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Tkacz, Karolina, Filip Rolski, Marcin Czepiel, Edyta Działo, Maciej Siedlar, Urs Eriksson, Gabriela Kania, and Przemysław Błyszczuk. "Haploinsufficient Rock1+/− and Rock2+/− Mice Are Not Protected from Cardiac Inflammation and Postinflammatory Fibrosis in Experimental Autoimmune Myocarditis." Cells 9, no. 3 (March 12, 2020): 700. http://dx.doi.org/10.3390/cells9030700.

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Progressive cardiac fibrosis is a common cause of heart failure. Rho-associated, coiled-coil-containing protein kinases (ROCKs) have been shown to enhance fibrotic processes in the heart and in other organs. In this study, using wild-type, Rock1+/− and Rock2+/− haploinsufficient mice and mouse model of experimental autoimmune myocarditis (EAM) we addressed the role of ROCK1 and ROCK2 in development of myocarditis and postinflammatory fibrosis. We found that myocarditis severity was comparable in wild-type, Rock1+/− and Rock2+/− mice at day 21 of EAM. During the acute stage of the disease, hearts of Rock1+/− mice showed unaffected numbers of CD11b+CD36+ macrophages, CD11b+CD36–Ly6GhiLy6chi neutrophils, CD11b+CD36–Ly6G–Ly6chi inflammatory monocytes, CD11b+CD36–Ly6G–Ly6c– monocytes, CD11b+SiglecF+ eosinophils, CD11b+CD11c+ inflammatory dendritic cells and type I collagen-producing fibroblasts. Isolated Rock1+/− cardiac fibroblasts treated with transforming growth factor-beta (TGF-β) showed attenuated Smad2 and extracellular signal-regulated kinase (Erk) phosphorylations that were associated with impaired upregulation of smooth muscle actin alpha (αSMA) protein. In contrast to cardiac fibroblasts, expanded Rock1+/− heart inflammatory myeloid cells showed unaffected Smad2 activation but enhanced Erk phosphorylation following TGF-β treatment. Rock1+/− inflammatory cells responded to TGF-β by a reduced transcriptional profibrotic response and failed to upregulate αSMA and fibronectin at the protein levels. Unexpectedly, in the EAM model wild-type, Rock1+/− and Rock2+/− mice developed a similar extent of cardiac fibrosis at day 40. In addition, hearts of the wild-type and Rock1+/− mice showed comparable levels of cardiac vimentin, periostin and αSMA. In conclusion, despite the fact that ROCK1 regulates TGF-β-dependent profibrotic response, neither ROCK1 nor ROCK2 is critically involved in the development of postinflammatory fibrosis in the EAM model.

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Fagg, M. C. "Resonant Rocks, 'Rock Gongs', Idiophones And Lithophones." Geological Curator 6, no. 1 (April 1994): 16. http://dx.doi.org/10.55468/gc178.

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I have been studying the uses of resonant rocks, and compiling a gazetteer of'rock gongs'. These are found worldwide, and are naturally placed and naturally tuned rocks, boulders, stalagmites and stalactites, which have been used as lithophones - in contrast to other lithophones (Chinese chime stones and "barxylophones" of stone) which are artificially tuned and are portable. It is puzzling why some rocks ring and others do not.

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Tulkin, Annakulov, Nusratullo Ziyadov, and Farhod Abdikarimov. "Analysis of overburden transportation by conveyor transport as part of a cyclic-flow technology." E3S Web of Conferences 417 (2023): 06006. http://dx.doi.org/10.1051/e3sconf/202341706006.

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This article discusses the use of belt conveyors for transporting overburden from open pits. The main technical and economic parameters of powerful belt conveyors that operate as part of a cyclic-flow technology for the development and transportation of rocks are given. The main conclusions on the effective use and further development of belt conveyors for transporting rocky rocks are given.

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Zhang, Guang, Jing Xi Chen, and Bin Hu. "The Brittle-Ductile Transition Character of Rocks and Its Effect on Rockbursts." Key Engineering Materials 261-263 (April 2004): 171–76. http://dx.doi.org/10.4028/www.scientific.net/kem.261-263.171.

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The brittle-ductile character is one of the important mechanical indexes of rocks and also one of the important affecting factors of rockburst. Both conventional and true triaxial tests have shown that the brittle-ductile character of rocks varies with the variation in rocks stress state and stress path, but these two kinds of tests have revealed totally different laws of brittle-ductile transition. This present paper analyses the results from two tests firstly and then summarizes the effect of rock’s brittle-ductile transition character on rockburst and finally points out the deficiency in present studies of rockburst.

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Lisbôa da Costa, Danúbia, Ingrid Mayara Medeiros Fernandes, Aluska Nascimento Simões Braga, Rosiane Maria da Costa Farias, Romualdo Rodrigues Menezes, and Gelmires Araújo Neves. "Microstructural Characterization of Ornamental Rock Samples: Cariri Rocks." Materials Science Forum 869 (August 2016): 159–63. http://dx.doi.org/10.4028/www.scientific.net/msf.869.159.

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Ornamental rocks are among the most promising business areas of the mineral sector, raising the necessity for, besides beauty, investments in quality, safety and characterization in the various application fields of these rocks. So, this work aims at the microstructural characterization of the class of these rocks: the Cariri Rocks, also known the limestone, which are calcareous rocks mainly formed by calcium and magnesium carbonate, possibly presenting variations due to their origins. For characterization, we studied four samples, being two from Chapada do Apodi and two from Chapada do Araripe, characterized physically and micro-structurally through chemical analysis, X-ray diffraction, optical micrography and porosimetry tests. The results prove that the limestones are calcitic and dolomitic, and present porosity varying from 5 to 15%, with pores concentration between 100nm and 10μm, besides the high microstructural heterogeneity.

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Sossi, Paolo A., and Anat Shahar. "Ironing Out Isotopic Differences Among Rocky Bodies." Elements 17, no. 6 (December 1, 2021): 407–12. http://dx.doi.org/10.2138/gselements.17.6.407.

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The variability of iron isotopes among rocky bodies in the inner Solar System provides a window onto the diversity of materials and mechanisms from which they formed. The magnitude of isotopic variation in mantle-derived rocks within a given body is similar to that between different planetary bodies. Isotopic signatures arising from primordial events, namely, evaporation/condensation, core formation and melting/crystallization, may be progressively diluted, modified, and redistributed over time by global recycling processes such as plate tectonics. Here, we assess the relative influence of these primordial mechanisms on the iron isotope compositions of igneous rocks and their implications for the structure and accretion histories of rocky planets.

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Ren, Jia Guo, and Qian Qian Wu. "Discussion on Geological Experiment Technology in Geological Work." Advanced Materials Research 616-618 (December 2012): 60–63. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.60.

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This essay puts silicate rocks test as example on the basic of the analysis of new technology and method of geological experiment. This essay analyses the experimental principal and process of silicate rock’s total iron content, and it based on geology experimental operation process. The essay tries to probe into silicate rock’s mineral chemical composition, rock structure and tectonics through the research of the iron content and other chemical components of silicate rocks. Furthermore, this essay also estimates the optional mineral’s component content of sandstone ore, and then evaluates mining products and industrial and economic value. It is very important to guide the development of the mine.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips." Rocks & Minerals 60, no. 1 (January 1985): 36. http://dx.doi.org/10.1080/00357529.1985.11764368.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips." Rocks & Minerals 60, no. 3 (May 1985): 143–44. http://dx.doi.org/10.1080/00357529.1985.11764392.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips." Rocks & Minerals 60, no. 5 (September 1985): 245. http://dx.doi.org/10.1080/00357529.1985.11764416.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips." Rocks & Minerals 60, no. 6 (November 1985): 292. http://dx.doi.org/10.1080/00357529.1985.11764429.

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Titamgim, R. Dirk. "Questions and Answers about Rocks Rock Chips." Rocks & Minerals 61, no. 1 (January 1986): 40. http://dx.doi.org/10.1080/00357529.1986.11768433.

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Titamgim, R. Dirk. "Questions and Answers about Rocks Rock Chips." Rocks & Minerals 61, no. 2 (March 1986): 93–94. http://dx.doi.org/10.1080/00357529.1986.11768447.

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Titamgim, R. Dirk. "Questions and Answers about Rocks Rock Chips." Rocks & Minerals 61, no. 6 (November 1986): 363. http://dx.doi.org/10.1080/00357529.1986.11768471.

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Titamgim, R. Dirk. "Questions and Answers about Rocks Rock Chips." Rocks & Minerals 64, no. 3 (May 1989): 229–30. http://dx.doi.org/10.1080/00357529.1989.11761761.

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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips." Rocks & Minerals 67, no. 6 (December 1992): 410–15. http://dx.doi.org/10.1080/00357529.1992.9926513.

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Dietrich, R. V. "Questions and Answers about Rocks: Rock Chips." Rocks & Minerals 69, no. 2 (April 1994): 122–27. http://dx.doi.org/10.1080/00357529.1994.9926587.

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Dietrich, R. V. "Rock Chips Questions & Answers about Rocks." Rocks & Minerals 70, no. 5 (October 1995): 340–42. http://dx.doi.org/10.1080/00357529.1995.9926644.

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Dietrich, R. V. "Rock Chips: Questions & Answers about Rocks." Rocks & Minerals 71, no. 6 (December 1, 1996): 412–16. http://dx.doi.org/10.1080/00357529.1996.9925634.

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Pujar, Anant G., A. Sreenivasa, and Ajaykumar N. Asode. "Petrography and Provenance Study of South-Central Part of Kaladgi Basin, Belgaum, Karnataka, India." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 108–12. http://dx.doi.org/10.46660/ijeeg.vol11.iss1.2020.421.

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The area under investigation covers the south-central part of Kaladgi series comprising of sedimentary rocks, mainly quartzarenites. From the geological point of view the study area comprises southcentral part of Kaladgi basin covering around 54 km2 which encompasses rocky hills of moderate height, showing three types of facies i.e., argillaceous, arenaceous and rudaceous. Among these three, arenaceous facies is more prominent in the area. These sedimentary rocks rest unconformably over gneisses. Detailed study of the rocks exposed are done by studying the petrological aspects of the rock samples which were subjected to microscopic studies, bifurcating different minerals and counting each parameter of the minerals which is plotted in the QFR ternary diagram and further illustrating the tectonic provenance of the area. Present work mainly focuses on the studies related to petrological, diagenesis and provenance of the study area where the rocks exposed in the vicinity are quartz arenites indicating that these sediments were deposited in a riverine condition.

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Pujar, Anant G., A. Sreenivasa, and Ajaykumar N. Asode. "Petrography and Provenance Study of South-Central Part of Kaladgi Basin, Belgaum, Karnataka, India." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 108–12. http://dx.doi.org/10.46660/ojs.v11i1.421.

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The area under investigation covers the south-central part of Kaladgi series comprising of sedimentary rocks, mainly quartzarenites. From the geological point of view the study area comprises southcentral part of Kaladgi basin covering around 54 km2 which encompasses rocky hills of moderate height, showing three types of facies i.e., argillaceous, arenaceous and rudaceous. Among these three, arenaceous facies is more prominent in the area. These sedimentary rocks rest unconformably over gneisses. Detailed study of the rocks exposed are done by studying the petrological aspects of the rock samples which were subjected to microscopic studies, bifurcating different minerals and counting each parameter of the minerals which is plotted in the QFR ternary diagram and further illustrating the tectonic provenance of the area. Present work mainly focuses on the studies related to petrological, diagenesis and provenance of the study area where the rocks exposed in the vicinity are quartz arenites indicating that these sediments were deposited in a riverine condition.

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Lozhnikov, O. V., V. O. Adamova, and M. M. Slivenko. "Justification of the safe parameters of recreational zones during the reclamation of watered residual quarry spaces." Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, no. 5 (October 30, 2024): 85–92. http://dx.doi.org/10.33271/nvngu/2024-5/085.

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Purpose. To determine the safe parameters of the recreational zones created in the residual space of the quarry taking into account the physical and mechanical properties of waste rocks in a watered state. Methodology. The Bishop Simplified Method is used to determine the influence of the irrigation level of the residual quarry space on the stability of the embankment from different types of mining rocks when creating a recreational area during reclamation works. Findings. The safe parameters of recreational areas during their construction in the watered residual space of the quarry were established taking into account the physical and mechanical properties of embankments made of sand, loam, and crushed rock by determining the stability of their slopes. The obtained results are necessary for the implementation of project works on the development of technological schemes for the reclamation of the residual spaces of construction materials quarry for the recreational direction of post-mining. Originality. The influence of the height of the rock embankment formation on the stable angle of inclination of the watered slope was established, which allowed determining that with an increase in the aggregates embankment height from 20 to 80 m, the safe angle of the slope will decrease from 46 to 26°. It was determined that the lowest FOS indicator is 0.57 when using sand rocks for an embankment height of 80 m at a water content of 40 %. It was established that with partial flooding of the rock embankment by 45–50 % for sandy, loamy and rocky rocks, there is a significant decrease in the coefficient of the reserve of stability by 1.4–1.5 times, in contrast to the absence of water or complete flooding, which confirms the negative impact of partial flooding of embankments and reducing the stability of their slopes. Practical value. It was determined that when forming an embankment 20 m high from loamy rocks, the volume of reclamation works will be 1.34 times less compared to sandy rocks, but 1.02 times larger than rocky rocks. When the height of the embankment increases to 80 m, the volume of reclamation works when replacing loam with sand will increase to 1.87 and 1.12 times when using crushed stone. However, taking into account the market value of materials, when using loam, the cost of construction will decrease by 2.5 times compared to sandy rocks and 3.2 times – to crushed stone, with an embankment height of 20 m. When the embankment height increases to 80 m, the cost of materials will increase by 3.5 and 3.8 times when loamy rocks are replaced by sand or crushed stone, respectively.

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Dietrich, R. V. "Questions and Answers about Rocks: Rock Chips: How Can I Get Others Interested in Rocks?" Rocks & Minerals 67, no. 2 (April 1992): 124–28. http://dx.doi.org/10.1080/00357529.1992.9926467.

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Morowitz, Harold J. "Rocks." Hospital Practice 26, no. 4 (April 15, 1991): 14–17. http://dx.doi.org/10.1080/21548331.1991.11704152.

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Cooper, William E., and Wade C. Sherbrooke. "Choosing between a rock and a hard place: Camouflage in the round-tailed horned lizard Phrynosoma modestum." Current Zoology 58, no. 4 (August 1, 2012): 541–48. http://dx.doi.org/10.1093/czoolo/58.4.543.

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Abstract The round-tailed horned lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats (uniform sand or sand with surface rocks approximately the same size as lizards). An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detection was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P. modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks (masquerade) enhances camouflage attributable to coloration and immobility.

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Harriott, Vicki J., Simon A. Banks, Roland L. Mau, Darren Richardson, and Lisa G. Roberts. "Ecological and conservation significance of the subtidal rocky reef communities of northern New South Wales, Australia." Marine and Freshwater Research 50, no. 4 (1999): 299. http://dx.doi.org/10.1071/mf98042.

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The subtropical rocky reefs of Cook Island, Julian Rocks and the South West Rocks area form part of a chain of islands and reefs with significant coral cover from the Queensland border (28˚S) to the southern extent of extensive coral communities in coastal Australia (31˚S). Benthic communities at 18 subtidal sites at the three localities were surveyed quantitatively by video-transects, and coral species lists were compiled. Twenty-eight coral species previously unrecorded for these localities were identified, increasing the species richness of hermatypic corals reported for the northern NSW region (excluding the Solitary Islands) from 14 to 43. Coral species richness declined with latitude. Benthic communities were generally dominated by turfing and macroalgal species, with Pyura, sponges, and barnacles locally abundant. Scleractinian coral cover ranged from 0% to 42.6% per site, with highest coral cover at the most southern site. Julian Rocks is a designated Aquatic Reserve, and Marine Parks have been suggested for all three localities. Selection of Marine Protected Areas requires information on their ecological significance. These surveys report the first quantitative information on the shallow- water, rocky-reef communities in the region, which is a vital step in assessing their ecological significance.

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Grzelak, Katarzyna, and Piotr Kuklinski. "Benthic assemblages associated with rocks in a brackish environment of the southern Baltic Sea." Journal of the Marine Biological Association of the United Kingdom 90, no. 1 (January 14, 2010): 115–24. http://dx.doi.org/10.1017/s0025315409991378.

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Sandy bottoms, with local patches of rocks, dominate the southern Baltic Sea coast. These rock patches create three-dimensional habitats with additional niches that can support diverse assemblages of organisms. In this study we investigated macrofaunal assemblages associated with the boulder field in the brackish Gulf of Gdansk. Of the 30 recorded taxa three animal species (Mytilus trossulus, Balanus improvisus and Electra crustulenta) together with five species of algae were directly attached to rocks. These engineering organisms provided habitats for a further 22 taxa. Among the fauna directly associated with rocks, barnacles (76%) were the most abundant while among indirectly associated biota, oligochaetes were the dominant group (45%). Rock size and algal biomass explained most variance in macrofaunal structure of the assemblages investigated. There were statistical differences in assemblage structure between two separate localities within the rocky patch, despite environmental homogeneity (salinity, water temperature and structure of sea bottom). These differences in assemblage structure were mostly due to differences in dominance of particular species rather than in species composition. Our results show that rocky patches in an otherwise soft sediment habitat provide additional living space for macrofauna leading to an increase in local biodiversity and organismal abundance.

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Gomes, Rickardo, and Valdeck Gomes. "The marble industry and its evolution since 1990 in Brazil: A bibliographic review." World Journal of Advanced Research and Reviews 19, no. 1 (July 30, 2023): 062–68. https://doi.org/10.5281/zenodo.8437162.

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The Brazilian stoneworking industry has undergone various structural, cultural, and technological changes since the 1990s. The introduction of multi-wire saws has made extracting harder rocks such as quartzites possible, increasing productivity. The arrival of modern cutting and finishing machinery has facilitated the production of slabs and met the demands of an increasingly demanding and selective market. The use of resin treatments for slabs has been a significant advance. This context has elevated Brazil as one of the largest exporters of slabs for the external market while also becoming one of the largest consumers of natural rocks. This study utilized a qualitative approach, with a literature review as the chosen research procedure. The results highlight that the rock market in Brazil, in general, primarily serves the construction industry, which is growing year after year. Nevertheless, stoneworking companies need to keep up with this growth to meet market demands.

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SINCLAIR, BRADLEY J. "Two new synonyms from Tibet (Diptera: Empididae: Clinocerinae)." Zootaxa 4268, no. 2 (May 16, 2017): 291. http://dx.doi.org/10.11646/zootaxa.4268.2.8.

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The subfamily Clinocerinae (Empididae, Diptera) are aquatic dance flies, most commonly encountered in fast flowing rocky streams and creeks. The adults often rest on emergent rocks and are rather common in temperate regions.

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Mack, Greg H., and T. Jerzykiewicz. "Provenance of post-Wapiabi sandstones and its implications for Campanian to Paleocene tectonic history of the southern Canadian Cordillera." Canadian Journal of Earth Sciences 26, no. 4 (April 1, 1989): 665–76. http://dx.doi.org/10.1139/e89-057.

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Late Campanian to Early Paleocene sandstones of the Alberta Foothills were derived from three types of rocks: (i) andesitic–dacitic volcanic rocks that were presumably comagmatic with middle to late Mesozoic plutons in the Omineca Crystalline Belt; (ii) low-grade metamorphic rocks in the suprastructure of the Omineca Crystalline Belt; and (iii) sedimentary rocks in die Rocky Mountain Thrust Belt, principally pelitic rocks in the western Main Ranges and carbonates and chert-arenites in the eastern Main and Front ranges. A paucity of quartzo-feldspathic rocks fragments and potassium feldspar indicates that the core of the Omineca Crystalline Belt was not extensively exposed at that time.Vertical trends in composition of the sandstones reveal five petrographic stages. Stage I is dominated by volcanic rock fragments and plagioclase, suggesting that initial progradation of the sediment was largely a response to coeval volcanism or tectonic emplacement of older volcanic rocks. Stages III and V are characterized by a significant decrease in the relative proportion of metamorphic detritus and an increase in the proportion of carbonate and chert detritus. These stages may represent periods of thrusting in the eastern Main Ranges or Front Ranges. In contrast, stages II and IV display increases in metamorphic detritus and stage II shows a concomitant decrease in carbonate and chert detritus, trends that indicate wearing down of the eastern Main Ranges or Front Ranges thrust sheet(s) and reintegration of the Omineca Crystalline belt and the western Main Ranges into the drainage basin. The compositional stages indicative of thrust events are associated with coarse facies, including the Entrance and High Divide Ridge conglomerates, whereas those stages indicative of tectonic quiescence are associated with fine-grained facies including coal.

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Peng, Yizhou, and I. Y. Grigorieva. "The reasons for the inheritance of the composition and properties of red-colored soils of the modern weathering crust within the western part of the Sichuan Basin of China." Geoèkologiâ, no. 3 (December 21, 2024): 44–58. https://doi.org/10.31857/s0869780924030057.

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In this work, we conducted an experimental evaluation and analysis of the characteristics and makeup of red-colored rocks from four representative Cretaceous and Jurassic sedimentary sequences in the western Sichuan Basin of China, as well as their weathering products. To determine the direction of weathering processes and the cause-and-effect link between the characteristics and composition of the parent rocks and the excess chemical components in the weathered soils, the chemical index of alteration was calculated. The findings demonstrated that, with regard to features like color, density of solid component, organic carbon content, granulometric composition, pH, mineral composition, and content of main chemical elements, all samples of weathered (dispersed) soils are quite comparable to the parent rocks. All samples of weathered soils and parent rocks exhibit similar chemical weathering characteristics and an index, according to the results of the CIAcorr calculation and the examination of the A–CN–K triangle diagrams. Furthermore, all of them have attained a moderate level of chemical weathering, with samples from Jurassic rocks (J3p, J3s, and J2s) having far lower weathering intensities than those from Cretaceous rocks (K1c). The red-colored rocks are characterized by weak chemical weathering and rapid development of physical weathering. This weathering characteristic can be attributed to the parent rock’s uniform texture and mostly clayey composition, which break down readily in environments with high humidity and plenty of heat. The low level of chemical weathering is due to the fact that the parent rock itself has undergone a significant change in chemical composition during sedimentation and subsequent diagenesis, and has acquired a high degree of resistance to subsequent transformation under modern conditions. Therefore, the characteristics and makeup of purple soil are mostly determined by the parent rock.

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YATSENKO, Ivan, Sergey SKUBLOV, Ekaterina LEVASHOVA, Olga GALANKINA, and Sergey BEKESHA. "Composition of spherules and lower mantle minerals, isotopic and geochemical characteristics of zircon from volcaniclastic facies of the Mriya lamproite pipe." Journal of Mining Institute 242 (May 25, 2020): 150. http://dx.doi.org/10.31897/pmi.2020.2.150.

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The article presents the results of studying the rocks of the pyroclastic facies of the Mriya lamproite pipe, located on the Priazovsky block of the Ukrainian shield. In them the rock's mineral composition includes a complex of exotic mineral particles formed under extreme reduction mantle conditions: silicate spherules, particles of native metals and intermetallic alloys, oxygen-free minerals such as diamond, qusongite (WC), and osbornite (TiN). The aim of the research is to establish the genesis of volcaniclastic rocks and to develop ideas of the highly deoxidized mantle mineral association (HRMMA), as well as to conduct an isotopic and geochemical study of zircon. As a result, groups of minerals from different sources are identified in the heavy fraction: HRMMA can be attributed to the juvenile magmatic component of volcaniclastic rocks; a group of minerals and xenoliths that can be interpreted as xenogenic random material associated with mantle nodules destruction (hornblendite, olivinite and dunite xenoliths), intrusive lamproites (tremolite-hornblende) and crystalline basement rocks (zircon, hornblende, epidote, and granitic xenoliths). The studied volcaniclastic rocks can be defined as intrusive pyroclastic facies (tuffisites) formed after the lamproites intrusion. Obviously, the HRMMA components formed under extreme reducing conditions at high temperatures, which are characteristic of the transition core-mantle zone. Thus, we believe that the formation of primary metal-silicate HRMMA melts is associated with the transition zone D".

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Journal articles on the topic 'Rocks'

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