Rock masses stresses investigation based on overcoring with CSIRO cell test and 3D finite element modeling in Aqabat Al-Sulbat Road at Aseer Province, Saudi Arabia: Numerical approach

Rock masses slopes stability is a real problem and represents an important concern in Aseer Province, in order to avoid rock fall process on the main roads. For this reason, it is necessary to explore, inspect, investigate, and understand the natural stresses within these rock masses taking into a consideration the third dimension. In this sense, the state of stresses within the rock masses depends on the characteristics of Commonwealth Scientific and Industrial Research Organization (CSIRO) cell and the dimension of the overcoring hole. Furthermore, in order to achieve the 3D modeling, the characteristics of the rock masses mentioned before are introduced in the model using “Surfrac” program written in Pascal and FORTRAN, coupled with “Abaqus” software to simulate the stresses matrix in the model. As a result, the main findings of this research are summarized in three points: the first is dealing with the CSIRO cell itself, where the direction of the gauge is important during the measurement of stresses; in fact, the perpendicular gauges work better than those parallel to the hole axis. The second is evident from the model that the direction of hole must be perpendicular to the dip direction of the rock layers, allowing giving better results compared to others. The third is the selection of the measurement site requiring involving the regional stresses of the study area according to geological investigation. Finally, it is interesting to carry out geophysical exploration in the site to understand the local tectonic movement of rock masses. Moreover, a detailed map can highlight the main fractures and faults network and overlap them with the most important projects deployed in Aseer province for maintenance and monitoring.

Promising selection of onions in the South of Russia

В последние десятилетия требования к новым сортам и гибридам репчатого лука существенно возрастают. Современные сорта и гибриды лука репчатого должны обладать стабильными проявлениями основных хозяйственно ценных признаков при разных условиях выращивания. Приоритетное направление в селекции лука репчатого – не только селекция на продуктивность, но и на скороспелость, пригодность к транспортировке, которые включают в себя комплекс признаков (округлая форма луковицы, ее плотность, прочность прикрепления кроющих сухих чешуй). Важный признак – лежкость луковиц при хранении, для чего ведется селекционная работа на высокое содержание сухого вещества и сахарозы. Цель работы – создать новые сорта и гибриды лука репчатого для юга России с комплексом хозяйственно полезных признаков. Исследования проводили в 2015–2020 годах в открытом грунте на Бирючекутской овощной селекционной опытной станции – филиал ФГБНУ ФНЦО, расположенной в Ростовской области. Почвы в опытах – черноземы обыкновенные. Мощность гумусового горизонта 70 см. Содержание гумуса в пахотном слое 4,2%. Погодные условия в годы проведения опытов были типичными для климатической зоны юга России. Климат – континентальный, с безморозным периодом более 260 дней, жарким и засушливым летом и относительно короткой и теплой зимой. За годы исследований был собран разнообразный материал из разных регионов мира. Собранные сорта и гибриды оценивали по наличию ценных признаков и свойств, на их основе создавали линейный материал источников и доноров признаков, востребованных в селекционных программах. Из лучших линий сформирован банк источников и доноров наиболее важных признаков – коллекция в количестве 100 образцов. Среди изученных образцов лука репчатого были выделены генисточники ценных признаков для различных направлений селекции культуры в условиях юга России. Наиболее устойчивые к региональным стрессам генотипы включали в гибридизацию, а также на их основе создавали линейный материал. Параллельно шла сортовая и гетерозисная селекция. По результатам конкурсного испытания выделился образец GL-5 Л 40 (Титан), который был передан в Государственное сортоиспытание. In recent decades, the requirements for new varieties and hybrids have increased significantly. Modern varieties and hybrids of onion should have stable manifestations of the main economic and valuable characteristics under different growing conditions. Priority areas in the selection of onions are not only selection for productivity, but also for precocity, suitability for transportation, which include a set of characteristics (the rounded shape of the bulb, its density, the strength of attachment of the covering dry scales). An important feature is also the keeping quality of bulbs during storage, for which breeding work is conducted for a high content of dry matter and sucrose. The aim of this work is to create new varieties and hybrids of onion for the South of Russia with a complex of economically useful characteristics. The study was performed on Birutchecutskaya Vegetable Experimental Station – branch of FSBSI FSVC, located in the Rostov region in 2015–2020 in the open field. The soils in the experiments are ordinary black earth. The thickness of the humus horizon is 70 cm. The humus content in the arable layer is 4.2%. Weather conditions during the experiments were typical for the climate zone of southern Russia. The climate is continental, with a frost-free period of more than 260 days, hot and dry summers, and relatively short and warm winters. Over the years of research, various materials from different regions of the world have been collected. The collected varieties and hybrids were evaluated based on the presence of valuable traits and properties on their basis, a linear material of sources and donors of traits that are in demand in breeding programs was created. From the best lines, a bank of sources and donors of the most important features is formed – a collection of 100 samples. Among the studied onion samples, sources of valuable traits for various areas of culture selection in the South of Russia were identified. The most resistant genotypes to regional stresses were included in hybridization, and linear material was created on their basis. In parallel, there was varietal and heterosis selection. According to the results of the competitive test, a sample of GL-5 L 40 (Titan) was produced, which was transferred to the State variety testing.

Synthesis of computer simulation and machine learning for achieving the best material properties of filled rubber

Molecular dynamics (MD) simulation is used to analyze the mechanical properties of polymerized and nanoscale filled rubber. Unfortunately, the computation time for a simulation can require several months’ computing power, because the interactions of thousands of filler particles must be calculated. To alleviate this problem, we introduce a surrogate convolutional neural network model to achieve faster and more accurate predictions. The major difficulty when employing machine-learning-based surrogate models is the shortage of training data, contributing to the huge simulation costs. To derive a highly accurate surrogate model using only a small amount of training data, we increase the number of training instances by dividing the large-scale simulation results into 3D images of middle-scale filler morphologies and corresponding regional stresses. The images include fringe regions to reflect the influence of the filler constituents outside the core regions. The resultant surrogate model provides higher prediction accuracy than that trained only by images of the entire region. Afterwards, we extract the fillers that dominate the mechanical properties using the surrogate model and we confirm their validity using MD.

STRUCTURAL ANALYSIS OF THE WICHITA UPLIFT AND STRUCTURES IN THE ANADARKO BASIN, SOUTHERN OKLAHOMA

We have constructed regional structural transects across the Wichita Uplift and adjacent Anadarko Basin to show the relationship between thick-skinned basement-involved structures and thin-skinned detached fold-thrust structures. Slip from the basement-involved structures in the Wichita Uplift is transferred along two major detachments into the Anadarko Basin. Our interpretation is that along the northwestern margin, the Wichita Uplift is marked by a zone of frontal imbricates forming a triangular wedge with most of the slip dissipated along the Wichita front. Paleozoic units show tight folding with overturned beds in the frontal zone. The uplift is episodic as indicated by the truncation of major faults along unconformities and their subsequent reactivation. In contrast, along the southeast margin, a significant part of the slip is transferred into structures in the Anadarko Basin. These structures are tight faulted-detachment folds that formed above a major detachment within the Springer Shale, cored by broader structures detaching at the base of the Arbuckle Group. Examples include the Carter-Knox, Cement-Chickasha, and Cruce structures. Oblique faults with normal and strike-slip components cut some of these structures, resulting in more complex geometries. We propose that pre-existing normal faults of Precambrian-Cambrian age were either reactivated along the Wichita Uplift, or controlled the location of the Pennsylvanian age structures in the Anadarko Basin. Progressive rotation of regional stresses from northeast-southwest to a more east-northeast-west-southwest direction during the Pennsylvanian impacted the tectonic history of the area. We used 2D and 3D seismic, well log data, and surface geology were used to evaluate the structural styles and tectonic evolution of the Wichita Uplift and the Anadarko Basin.

Multi-Attribute Analysis Using Coherency and Ant-Tracking Techniques for Fault and Fracture Detection in La Florida Anticline, Llanos Foothills, Colombia

We present techniques to reduce noise and enhance seismic quality, making possible the first multi-attribute analysis of a 3D seismic volume in the Llanos Foothills (La Florida anticline) of Colombia using coherency and ant-tracking techniques for fault and fracture detection. The results could help reduce risk in models of reservoir fracture porosity and permeability. The dominant fracture strike direction in the studied seismic volume (La Florida anticline) is NE–SW (055 ± 20°), parallel to the structural strike of the adjacent Eastern Cordillera Foothills. The application of the ant-tracking technique also reveals the NE-SW fracture set for the reservoir rocks in the La Florida anticline as well as in the non-folded reservoir rocks to the SE. We compared the fracture intensity and orientation in folded rocks with the fracture intensity and orientation in non-folded rocks. Our study showed NE-SW, NW-SE, and E-W fracture orientations in the non-folded seismic volume, suggesting that regional stresses could produce these fracture sets, not just folding processes as previously proposed. The NW-SE and WNW-ESE fracture sets are only found in the Guayabo Formation (11 Ma–Present). A right–lateral strike–slip displacement on the nearby Algeciras fault system in the last 2 m.y. may have generated WNW-ESE and NW-SE Riedel-type shear fractures in the study area.

Early syn-rift igneous dike patterns, northern Kenya Rift (Turkana, Kenya): Implications for local and regional stresses, tectonics, and magma-structure interactions

Four areas (Loriu, Lojamei, Muranachok-Muruangapoi, Kamutile Hills) of well-developed Miocene-age dikes in the northern Kenya Rift (Turkana, Kenya) have been identified from fieldwork and satellite images; in total, >3500 dikes were mapped. Three areas display NNW-SSE– to N-S–oriented dike swarms, with straight, radial, and concentric patterns in zones <15 km long, and indicate NNW-SSE to N-S regional maximum horizontal principal stress (SHmax) directions in the early to middle Miocene. Individual dikes are typically <2 m wide and tens to hundreds of meters long and have accommodated <2% extension. In places (Loriu, Lojamei, Lokhone high), dikes trend at a high angle to the rift trend, suggesting some local influence (e.g., overpressured magma chamber, cracked lid–style dike intrusions over a sill or laccolith, preexisting fabric in basement) on orientation, in addition to the influence from regional stresses. Only a minor influence by basement fabrics is seen on dike orientation. The early- to middle-Miocene dikes and extrusive activity ended a long phase (up to 25 m.y.) of amagmatic half-graben development in central Kenya and southern Turkana, which lay on the southern edge of the early (Eocene–Oligocene) plume activity. The Miocene dike sets and extension on major border faults in Turkana contrast with larger, more extensive arrays of dikes in evolved systems in the Main Ethiopian Rift that are critical for accommodating crustal extension. By the Pliocene–Holocene, magmatism and intrusion along dikes had become more important for accommodating extension, and the tectonic characteristics began to resemble those of rift basins elsewhere in the eastern branch of the East African Rift.

Supplemental Material: Early syn-rift igneous dike patterns, northern Kenya Rift (Turkana, Kenya): Implications for local and regional stresses, tectonics, and magma-structure interactions

ESRI Shapefiles of the mapped dike patterns, faults, and other features for this study.<br>