The Caucasus Territory Hot-Cold Spots Determination And Description Using 2D Surface Waves Tomography

In order to identify and describe Hot-Cold spots inside the earth based on increasing and decreasing wave velocity anomalies, this paper attempts to generate the first 2D tomographic maps of Rayleigh surface wave velocity dispersion curves, by using ~1200 local-regional earthquake data and ~30000 vertical (Z) components of earthquake data waveform energy with magnitude M≥4 from 1999 to 2018 in a periods range of 5 to 70 seconds and a grid spacing of 0.2º×0.5º for a depth of ~200 km. To conduct this, a generalized 2D linear inversion procedure developed by Yanovskaya and Ditmar has been applied to construct the first 2D Rayleigh tomography velocity maps in order to understand better the regional tectonic activities in the enigmatic ongoing collision-compressed edge zone of the Eurasian-Arabic plates. In this study, we assumed that low-velocity (slow) region with dark red shade is hot spot and high-velocity (fast) region with dark blue-green-yellow is a cold spot. In short and medium periods were determined the number of 15 and 2 hot spots with a depth of 7 to 108 km, respectively. In long-periods and a depth of ~200 km, most part of the area study has covered by low-velocity anomaly.

Development of a Method for Evaluating the Technical Condition of a Car’s Hybrid Powertrain

The article presents the results of a study performed and substantiated based on the principles of a new method of diagnostics of technical conditions of a hybrid powertrain regardless of the structural diagram and design features of a hybrid vehicle. The presented new technology of the diagnostics of hybrid powertrains allows an objective complex assessment of their technical condition by diagnostic parameters in contrast to existing diagnostic methods. In the proposed method, a mechanism for the general standardization of diagnostic parameters has been developed as well as for determining the numerical values of the parameters of the powertrain. The control subset was used to control the learning error. As a result of debugging the system, the scatter of experimental and calculated points has decreased, which confirms the quality of debugging the tested fuzzy model. As a result of training the artificial neural network, the standard deviation of the error in the control sample was 0.012·Pk. A symmetry method of diagnostics of the technical state of a hybrid propulsion system was developed based on the concept of a neural network together with a neuro-fuzzy control with an adaptive criteria based on the method of training a neural network with reinforcement. The components of the vector functional include the criteria for control accuracy, the use of traction battery energy, and the degree of toxicity of exhaust gases. It is proposed to use the principle of symmetry of the guaranteed result and the linear inversion of the vector criterion into a supercriterion to determine the technical state of a hybrid powertrain on a set of Pareto-optimal controls under unequal conditions of optimality.

Combined linear regression and Monte Carlo approach to modelling exposure age depth profiles

We introduce a set of methods for analyzing cosmogenic-nuclide depth profiles that formally integrates surface erosion and muogenic production, while retaining the advantages of the linear inversion. For surfaces with erosion, we present solutions for both erosion rate and total eroded thickness, each with their own advantages. For practical applications, erosion must be constrained from external information, such as soil-profile analysis. By combining linear inversion with Monte Carlo simulation of error propagation, our method jointly assesses uncertainty arising from measurement error and erosion constraints. Using example depth profile data sets from the Beida River, northwest China and Lees Ferry, Arizona, we show that our methods robustly produce comparable ages for surfaces with different erosion rates and inheritance. Through hypothetical examples, we further show that both the erosion rate and eroded-thickness approaches produce reasonable age estimates so long as the total erosion less than twice the nucleon attenuation length. Overall, lack of precise constraints for erosion rate tends to be the largest contributor of age uncertainty, compared to the error from omitting muogenic production or radioactive decay.

Microseismicity of the Central Alpine Fault Region, New Zealand

<p>This study investigates the spatial and temporal patterns in microseismicity along the central section of the Alpine Fault, South Island, New Zealand. This section, between Harihari and Karangarua, has significantly lower seismicity than the regions to the northeast and southwest. Several hypotheses of mechanisms said to contribute to the anomaly have been proposed over the years including locked fault, slow slip, shallow creep and external fluids affecting the thermal regime and brittle-ductile transition. Focussing on the shallow crust, the contrasting seismic character is compared to the northern and southern sections from seismicity behaviour, focal mechanisms and seismogenic depth. A temporal array of eight seismographs (including three broadband instruments) was augmented with three GeoNet stations bounding the array. This provided an average spacing of 14 km and a magnitude cut-off of ML 1.6 compared to the GeoNet national network cut-off of ML 2.6 and station spacing of 80-100 km. The Gutenberg-Richter distribution for the four month time frame analysed defned a b-value of 0.75 plus or minus 0.06 which may indicate a locked, heterogeneous zone under high-stress from fluid pressure or a predominance of thrust mechanisms over the survey period. Seismicity over the deployment was within the average range of the last 15 years. The 'horseshoe' shaped seismicity pattern observed from long-term national catologue data is similar for smaller magnitudes. While the central portion of the Alpine Fault is quieter with unusually low b-value, the region is not aseismic. Neither does it experience the level of microseismicity seen in creeping faults. The brittle-ductile transition varies laterally along the fault and is estimated at up to 15 km for most of the survey region but closer to 10 km for the region associated with the highest orogenic uplift rates which compares well with past studies. A local magnitude scale was developed from direct linear inversion of the pseudoWood-Anderson amplitudes and event-station distances. A linear inversion of data from the standard New Zealand magnitude equation characterised an attenuation parameter of 0.0167 km minus 1; more than double the value used in national local magnitude calculations (of 0.0067 km minus 1). Swarm clustering dominates the seismicity character of the time frame. Utilising the earthquake relocation program HypoDD, a selection of clusters both near the Alpine Fault and away from it resolve to point sources. Those close to the Alpine Fault are located in what may be the footwall of the Fault which may indicate that the velocity model has located the events too far to the northwest.</p>

Microseismicity of the Central Alpine Fault Region, New Zealand

<p>This study investigates the spatial and temporal patterns in microseismicity along the central section of the Alpine Fault, South Island, New Zealand. This section, between Harihari and Karangarua, has significantly lower seismicity than the regions to the northeast and southwest. Several hypotheses of mechanisms said to contribute to the anomaly have been proposed over the years including locked fault, slow slip, shallow creep and external fluids affecting the thermal regime and brittle-ductile transition. Focussing on the shallow crust, the contrasting seismic character is compared to the northern and southern sections from seismicity behaviour, focal mechanisms and seismogenic depth. A temporal array of eight seismographs (including three broadband instruments) was augmented with three GeoNet stations bounding the array. This provided an average spacing of 14 km and a magnitude cut-off of ML 1.6 compared to the GeoNet national network cut-off of ML 2.6 and station spacing of 80-100 km. The Gutenberg-Richter distribution for the four month time frame analysed defned a b-value of 0.75 plus or minus 0.06 which may indicate a locked, heterogeneous zone under high-stress from fluid pressure or a predominance of thrust mechanisms over the survey period. Seismicity over the deployment was within the average range of the last 15 years. The 'horseshoe' shaped seismicity pattern observed from long-term national catologue data is similar for smaller magnitudes. While the central portion of the Alpine Fault is quieter with unusually low b-value, the region is not aseismic. Neither does it experience the level of microseismicity seen in creeping faults. The brittle-ductile transition varies laterally along the fault and is estimated at up to 15 km for most of the survey region but closer to 10 km for the region associated with the highest orogenic uplift rates which compares well with past studies. A local magnitude scale was developed from direct linear inversion of the pseudoWood-Anderson amplitudes and event-station distances. A linear inversion of data from the standard New Zealand magnitude equation characterised an attenuation parameter of 0.0167 km minus 1; more than double the value used in national local magnitude calculations (of 0.0067 km minus 1). Swarm clustering dominates the seismicity character of the time frame. Utilising the earthquake relocation program HypoDD, a selection of clusters both near the Alpine Fault and away from it resolve to point sources. Those close to the Alpine Fault are located in what may be the footwall of the Fault which may indicate that the velocity model has located the events too far to the northwest.</p>

Andesite prospect at West Sungkai of North Lampung: Its distribution based on electrical resistivity tomography

Infrastructure construction made andesite’s demand has increased, particularly in Lampung Province. In this research, its distribution in West Sungkai of North Lampung is mapped based on Electrical Resistivity Tomography (ERT) data from 6 lines, each of them was 186 m in length. Due to its excellent vertical resolution, Wenner configuration is performed. The research area is part of Quarter Holocene Volcanic (Qhv) formation. Lajur Barisan members consist of volcanic breccia, lava, and andesite-basalt tuff; thus, resistivity modeling is built within this aisle. Subsurface resistivity model has been created using the non-linear inversion method with promising low error at the third to fifth iterations, which marks an acceptable value. Using 2D and 3D ERT modeling, it is estimated that there are three mains of rocks based on their resistivity value: sandy tuff with 65 – 212 Ω m; tuff with 212 – 655 Ω m; and andesite with resistivity more than 655 Ω m. Andesite within this area is likely lava andesite which spread from the middle to the West and north. It is located at 5 – 35 m in depths with the reserve estimation of andesite is about 1.65 million tons.

Modeling long-term volcanic deformation at Kusatsu-Shirane and Asama volcanoes, Japan, using the GNSS coordinate time series

Long-term deformation of Kusatsu-Shirane and Asama volcanoes in central Japan were investigated using Global Navigation Satellite System (GNSS) measurements. Large postseismic deformation caused by the 2011 Tohoku earthquake—which obscures the long-term volcanic deformation—was effectively removed by approximating the postseismic and other recent tectonic deformation in terms of quadrature of the geographical eastings/northings. Subsequently, deformation source parameters were estimated by the Markov Chain Monte Carlo (MCMC) method and linear inversion, employing an analytical model that calculates the deformation from an arbitrary oriented prolate/oblate spheroid. The deformation source of Kusatsu-Shirane volcano was found to be a sill-like oblate spheroid located a few kilometers northwest of the Yugama crater at a depth of approximately 4 $$\text {km}$$ km , while that of Asama was also estimated to be a sill-like oblate spheroid beneath the western flank of the edifice at a depth of approximately 12 $$\text {km}$$ km , along with the previously reported shallow east–west striking dike at a depth of approximately 1 $$\text {km}$$ km . It was revealed that (1) volume changes of the Kusatsu-Shirane deformation source and the shallow deformation source of Asama were correlated with the volcanic activities of the corresponding volcanoes, and (2) the Asama deep source has been steadily losing volume, which may indicate that the volcano will experience fewer eruptions in the near future.

Inland Reservoir Water Quality Inversion and Eutrophication Evaluation Using BP Neural Network and Remote Sensing Imagery: A Case Study of Dashahe Reservoir

In this study, an inland reservoir water quality parameters’ inversion model was developed using a back propagation (BP) neural network to conduct reservoir eutrophication evaluation, according to multi-temporal remote sensing images and field observations. The inversion model based on the BP neural network (the BP inversion model) was applied to a large inland reservoir in Jiangmen city, South China, according to the field observations of five water quality parameters, namely, Chlorophyl-a (Chl-a), Secchi Depth (SD), total phosphorus (TP), total nitrogen (TN), and Permanganate of Chemical Oxygen Demand (CODMn), and twelve periods of Landsat8 satellite remote sensing images. The reservoir eutrophication was evaluated. The accuracy of the BP inversion model for each water parameter was compared with that of the linear inversion model, and the BP inversion models of two parameters (i.e., Chl-a and CODMn) with larger fluctuation range were superior to the two multiple linear inversion models due to the ability of improving the generalization of the BP neural network. The Dashahe Reservoir was basically in the state of mesotrophication and light eutrophication. The area of light eutrophication accounted for larger proportions in spring and autumn, and the reservoir inflow was the main source of nutrient salts.