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... The recognition of structures is fundamental to map generalization, furnishing structural information that assists in choosing and parameterizing generalization operators. We specifically focus on the process of recognizing groups of small polygons in geological maps as a prerequisite to subsequent aggregation or typification operators. Proximity between polygons represents an essential criterion ...
... To clarify the main factors that control deep carbonate rock gas reservoirs in the Jiulong Mountain area, China, reservoir fractures and caves were investigated. This study revealed, for the first time, that fault-dissolved body traps have formed in the Maokou Formation, Sichuan Basin, and that the identification of fault-dissolved bodies is key in the exploration process. In this study, high-prec ...
rocks, etc ; Africans; arts; fields; history; South Africa; Show all 6 Subjects
Abstract:
... Stone Age and rock art sites that Breuil would visit near Kimberley, South Africa, during and after the 1929 conference of the British and South African Associations for the Advancement of Science, were amongst the first he would see in Africa. Breuil's published observations and an autobiographical account afford a keyhole view on his initial thoughts with hints of ways these would develop, along ...
rocks, etc ; fluids; material forms; mathematical models; monitoring; Show all 5 Subjects
Abstract:
... This study develops a method to estimate the redistribution of elements during several associated metasomatic processes simultaneously involved in the formation of a geological complex. The method is based on classical mass balancing using isocon analysis. The proposed approach is applicable if geological prerequisites indicate that (a) the metasomatic rocks inherited some components (x, y, etc.) ...
carbonate rocks, etc ; carbon; evolution; oxygen; stratigraphy; strontium; Iran; Show all 7 Subjects
Abstract:
... This study addresses the timing implications of chemical stratigraphy and chronostratigraphic correlation of unconformity-related shallow water (neritic) carbonate rock units. Cenomanian–Santonian sequences (i.e., Sarvak and Ilam formations) host considerable volumes of hydrocarbon in the Zagros region of SW Iran, which represent good examples of unconformity-related reservoirs worldwide. Geochemi ...
rocks, etc ; area; engineering; engineers; fields; geometry; mountains; Himalayan region; Show all 8 Subjects
Abstract:
... We propose the new continuous slope mass rating (SMR) charts for easy calculation of SMR class of rock slopes in the field. SMR class can be determined by plotting the parallelism between dip directions of slope and discontinuity (slope dip direction and trend direction of intersection line in case of wedge failure) (A) in the x-axis and discontinuity dip amount (βⱼ) (plunge amount in case of wedg ...
carbonate rocks, etc ; air temperature; carbonates; groundwater; gypsum; karsts; Albania; Show all 7 Subjects
Abstract:
... The territory of Albania presents wide outcrops of soluble rocks, with typical karst landforms and the presence of remarkable carbonate aquifers. Many karst areas are located near the coasts, which results in a variety of environmental problems, mostly related to marine intrusion. This paper focuses on the brackish springs of Albania, which exhibit temperatures approximately equal to the yearly ai ...
volcanic rocks, etc ; Rhodophyta; flora; macroalgae; Aegean Sea; Mediterranean Sea; Show all 6 Subjects
Abstract:
... This study contains an updated checklist and new collections of marine algae from the coasts of the Aegean Sea and the Levantine Sea of Turkey. A total of 573 marine algal taxa at specific and infraspecific levels (137 brown algae, 318 red algae, and 118 green algae) are reported, 32 of which are regarded as endangered or threatened macroalgae (four green algae, nine red algae, and 19 brown algae) ...
carbonate rocks, etc ; computer software; direct contact; geometry; landscapes; lidar; Show all 6 Subjects
Abstract:
... Airborne light detection and ranging (LiDAR) and unmanned aerial vehicle-structure from motion (UAV-SfM) provide point clouds with unprecedented resolution and accuracy that are well suited for the digital characterization of rock outcrops where direct contact measurements cannot be obtained due to terrain or safety constraints. Today, however, how to better apply these techniques to the practice ...
rocks, etc ; Poisson distribution; control methods; deformation; engineering; engineers; mass; materials; Show all 8 Subjects
Abstract:
... The change in the stress state of the underground rock caused by excavation is the root cause of the deformation instability. Compensating for the stress change is one of the keys to effectively control the instantaneous deformation of rockbursts and the slow deformation of soft rocks in deep underground engineering. At present, the Platts pressure arch theory and the New Austrian Tunneling Method ...
volcanic rocks, etc ; brittleness; deformation; geometry; geophysics; microstructure; permeability; porosity; research; Show all 9 Subjects
Abstract:
... The permeability of volcanic rock controls the distribution of pore fluids and pore fluid pressure within a volcanic edifice, and is therefore considered to influence eruptive style and volcano deformation. We measured the porosity and permeability of a porous volcanic rock during deformation in the brittle and ductile regimes. In the brittle regime, permeability decreases by a factor of 2–6 up to ...
rocks, etc ; case studies; computers; engineering; engineers; exhibitions; imports; mass; shape; Show all 9 Subjects
Abstract:
... The presence of discontinuities in fractured rocks contributes to the formation of blocks. Characterizing the size and shape of the congregation of blocks in the rock mass provides a comprehensive understanding for studying its engineering properties. The existing block shape characterization method (BSCM) considers two factors: α describes the shortening of the minor principal axis of the block, ...
carbonate rocks, etc ; diffusivity; equations; geometry; horizontal wells; karsts; mathematical models; seepage; Show all 8 Subjects
Abstract:
... This paper presents a new method to obtain a semi-analytical solution for bottom hole pressure (BHP) of a horizontal well in fracture-cavity reservoirs. The basic building block of the method is to build a new source function suitable for the seepage of carbonate rock for the first time and obtain BHP step by step. This paper uses Laplace transform and Perturbation method to solve the diffusivity ...
carbonate rocks, etc ; X-radiation; contact angle; oils; petroleum; salinity; temperature; wettability; Show all 8 Subjects
Abstract:
... The wettability change from oil-wet towards more water-wet conditions by injecting diluted brine can improve oil recovery from reservoir rocks, known as low salinity waterflooding. We investigated the underlying pore-scale mechanisms of this process to determine if improved recovery was associated with a change in local contact angle, and if additional displacement was facilitated by the formation ...
volcanic rocks, etc ; carbon; denitrification; nitrates; nitrogen; polyesters; technology; temperature; total nitrogen; Show all 9 Subjects
Abstract:
... The denitrification performance of immobilized mixed aerobic denitrifying bacteria (IMADB) was investigated. IMADB displayed strong temperature adaptability under low Carbon/Nitrogen conditions. At 5, 15, and 25 °C, the nitrate removal efficiencies of volcanic rock and polyester fiber sponge immobilized system reached 83.95%-98.25% and 89.71%-98.14%, respectively. The nitrate content removed by th ...
rocks, etc ; Koreans; cracking; polluted soils; remediation; silty soils; surfaces; synergism; technology; Show all 9 Subjects
Abstract:
... Thermal plasma blasting technology has been widely applied for rock cracking. Though, the application for environmental remediation has yet to be reported. Since the delivery of remediation agents into diesel contaminated clayey zones are exceptionally challenging, herein, this study explores the effect of pilot-scale thermal plasma blasting for soil fracturing and concurrently dispersing the Fent ...
rocks, etc ; acoustics; artificial intelligence; energy; engineering; engineers; extracts; methodology; prediction; wills; Show all 10 Subjects
Abstract:
... The static and dynamic failure processes of hard rocks were simulated by compression tests to investigate the precursors of hard rock instability. In the tests, acoustic emission (AE) signals were acquired, and their clustering features were automatically extracted by the clustering unsupervised learning method. The results showed that a class of AE signals featured ‘high rise time, high ring coun ...
sedimentary rocks, etc ; gneiss; granite; landslides; probability; rain; regression analysis; water; South Korea; Show all 9 Subjects
Abstract:
... How landslide-triggering rainfall conditions vary with geology is unclear. The effects of three different geological conditions (gneiss, GN; granite, GR; sedimentary rock, SR) on variations in intensity–duration (I-D) conditions and rainfall characteristics responsible for initiating shallow landslides were examined using data from 476 landslides in South Korea from 1963 to 2018 and detailed stati ...
metamorphic rocks, etc ; absorption; data collection; goethite; magnetite; microscopy; mineralization; pyrite; surveys; Egypt; Show all 10 Subjects
Abstract:
... Through various scales of observation, ranging from remote sensing data, field investigations, hand specimens, microscopic petrographic examinations, XRD, to SEM, indicators of various mineralization types are highlighted in Ras El-kharit-wadi Khashir (Eastern Desert, Egypt). Systematic remote sensing exploration of the mineralized zones is performed through integrating Sentinel 2 and ASTER datase ...
carbonate rocks, etc ; aquifers; bedrock; electrical resistance; geophysics; karsts; landscapes; tomography; vadose zone; China; Show all 10 Subjects
Abstract:
... The soils and underlying weathered carbonate rock in karstic regions play an important role in the infiltration, storage, and retention of water and nutrients. Because of significant heterogeneity of the karst, the use of individual geophysical techniques is often not sufficient for unambiguous assessment of the irregular distributions of soils and underlying fractures. In this study, ground penet ...