This study evaluates Seasonal Auto-Regressive Integrated Moving Average (SARIMA) techniques for predicting river discharge up to 12 months ahead. The Sava River, Serbia, was chosen as the test basin because it plays a crucial role in regional water resource management. However, accurate long-term discharge prediction is challenging due to climatic variability and non-stationarity in hydrological series. Monthly discharge series from 1926 to 2022 at the Sremska Mitrovica station were modeled and forecasted using SARIMA and compared with Zero-Order Forecasting (ZOF) and Random Forests. The selected SARIMA model predicted discharge with a normalised Root Mean Square Error of 21% and a normalised Mean Absolute Error of 16% calculated as a percentage of mean observed discharge. This study evaluates both classical stochastic methods (SARIMA) and machine learning (Random Forest) for the Sava and underscores the potential for improved hydrological predictions in the Western Balkans. Future research should incorporate additional covariates and apply these models to diverse river systems to enhance predictive accuracy.
The velocities of the compressional and shear waves (VP and VS) were determined for seven parallel Multichannel Analysis of Surface Waves (MASW) traverses within the upstream basin of Chaq-Chaq Dam in Sulaimani, Kurdistan Region- Iraq. These traverses were executed with a spacing of 2 meters (m) between the geophones. The objective of this study was to investigate subsurface geological features, determine the depth to bedrock, assess bedrock strength, calculate primary and shear wave velocities, and explore potential causes for the collapse of the constructed Chaq-Chaq Dam. Data was collected using Geometrics Seismodule Controller software and processed using ParkSeis Software. The velocity results indicate that the study area comprises three geological layers: a surface soil layer on top, a middle layer of rock fragments, and a limestone layer at the bottom. The calculated Poisson’s ratio based on VP and VS values for these three layers ranges between 0.35 and 0.39 for the first layer, 0.30 and 0.33 for the second layer, and 0.24 and 0.25 for the third layer. These results suggest that the first layer has relatively high values of Poisson’s ratio, indicating an incompetent soil layer. The second layer exhibits moderate values, suggesting a fairly competent layer of rock fragments, while the third layer has low values, indicating a well-competent limestone layer. The findings also highlight deficiencies in the dam’s design, particularly in the southern parts where most of the traverses show the presence of sinkholes. These sinkholes are likely caused by water infiltration during the rainy winter season. When water pressure is applied to the dam, these sinkholes in the southwestern portion could be attributed as the cause of the dam collapsing. Additionally, the dam side was not properly intertied with the rocks forming the right bank of the dam.
This research focuses on Özkonak and the surrounding area in the Avanos district, investigating the relationship between tectonic lineaments and the formation of goethite and malachite mineralisation. The study aims to clarify how structural geological features influence the formation processes of these secondary minerals. Recent advances in satellite technology have greatly improved the effectiveness of remote sensing in mineral exploration. The study combined field surveys with Landsat-8 OLI/TIRS satellite imagery, processed using Geomatica, ENVI, and ArcGIS, to investigate the relationship between geological-tectonic lineaments and mineralisation patterns. The results indicate a strong correlation between mineralisation and tectonic lineaments, with significant concentrations of goethite and malachite mineralisation found to the west of Özkonak. This is particularly evident in areas characterised by imbricated thrust faults. These formations are likely to be secondary in the oxidation zone, suggesting the presence of primary sulphide deposits. The occurrence of mineralisation coincides with regions of significant tectonic lineaments, as shown by rose diagrams derived from both field and satellite data. The analysis revealed that the ore veins' position was N830W/170SW. The average orientation of the ore veins aligns with the N80-900W and N30-500E trending lineaments. In addition, a satellite-based surface temperature map indicates higher temperatures in the mineralised areas, which corresponds with the lineament maps. The results of this study could greatly enhance the exploration of primary sulphide deposits, which are the source of secondary mineralisation.
Sea-level variability on planetary time scales (10–100 d) is a prominent feature of the Adriatic Sea and an important preconditioner of coastal flooding. We characterized its properties in the present climate using the nearly century-long Bakar tide-gauge record (1929–2021) and mean sea-level pressure from ERA5 reanalysis, and assessed projected changes using three regional climate model simulations (ALADIN, CCLM, and RACMO). High coherence between sea level and mean sea-level pressure in the 10–100 d band justified using mean sea-level pressure as a proxy for planetary-scale sea level in future climate. Extreme planetary-scale episodes were defined as sea-level anomalies ≥ +19 cm and mean sea-level pressure ≤ -13.5 hPa, separated by at least ten days. In the past period, extreme sea-level episodes peaked in the cold season, occurred typically once or twice per year, lasted three to six days, and showed no significant century-scale trend in intensity, frequency, or duration. Evaluation of regional climate models for the period 1971–2000 showed that all models reproduced the observed seasonal cycle and episode intensity, while the CCLM and especially RACMO models tended to overestimate frequency and duration. Future projections (2039–2068, 2069–2098) under RCP4.5 and RCP8.5 indicated no robust changes in episode intensity, duration, or frequency suggesting that planetary-scale atmospheric forcing over the northern Adriatic is unlikely to change substantially in warmer climates. Consequently, future flood risk will be governed primarily by mean sea-level rise and its superposition with tides and storm surges, rather than by strengthened planetary-scale anomalies.
In this study, geodynamic processes in the Western Anatolia Region were analyzed using Interferometric Synthetic Aperture Radar (InSAR) and Global Navigation Satellite Systems (GNSS) data, incorporating wavelet transformation of InSAR time series based on GNSS observations. InSAR data were processed over a six-year period to produce line of sight (LOS) displacement maps. Ascending and descending track data were merged to derive information on both horizontal and vertical displacements. The InSAR-derived displacements were then compared with GNSS station data from the region to assess variations in the east and up components obtained by both techniques. Significant horizontal and vertical displacements were detected. While the Menemen Plain experienced a subsidence of up to 15 centimeters over a six-year period, the island of Samos experienced a rise of 29 centimeters. The performance of InSAR results was evaluated against GNSS data using Root Mean Square Error (RMSE). The RMSE values significantly decreased after applying corrections to the InSAR processing, indicating improved accuracy. For the DEUG station, the RMSE between InSAR and GNSS time series improved to 1.93% in the east component and 5.29% in the vertical component after wavelet-based noise removal. At the IZMI station, the RMSE was reduced to 2.62% (east) and 6.00% (vertical). Finally, at the CES1 station, the RMSE was reduced to 2.71% for the east component and 5.84% for the vertical component, all after correction.
This paper proposes a lightweight convolutional neural network model to identify the types of natural earthquake and blasting events quickly and accurately. Since an event is generally recorded by several stations, it is necessary to preprocess and classify the data based on the event beforehand. This ensures that different station waveforms of the same event do not appear in any two of the training sets, validation sets, and test sets. With the three-component waveforms recorded by stations after preprocessing as the input, the network model and hyperparameters are optimized by analyzing the average and variance in the accuracy and loss values of the verification set in the fivefold cross-validation, and the accuracy and loss curves in the training process. Finally, the classification results of all stations that achieve a certain signal-to-noise ratio for each event are taken as the output of this event type based on the principle that the majority prevails over the minority. This study uses 2,190 natural and blasting events recorded by the Hainan Seismic Network before August 2022, which includes 53,067 waveforms, to train and test the effectiveness of the model. Twenty percent of those events are selected randomly as the test set. The results showed that out of 438 randomly selected events, 427 were correctly identified, resulting in an accuracy rate of 97.48%. Specifically, the accuracy rate for seismic events was 95.59%, with a recall rate of 89.04%, while the accuracy rate for blasting events was 97.84%, with a recall rate of 99.18%. In conclusion, the convolutional neural network model proposed in this paper can rapidly and accurately identify natural and blasting types in Hainan.
The application of aeromagnetic anomalies to rare earth mineral (lepidolite) exploration in Ijero-Aramoko pegmatite field Southwestern Nigeria, has been carried out with a view to determining the locations and depth to the lineaments hosting the pegmatite bodies. The methodology adopted involved Euler deconvolution technique applied to the 2-D profile and gridded potential field data to obtain estimates of locations and depths of causative bodies. In this study, upward continuation was applied to transform the aeromagnetic data, originally measured at a flight altitude of approximately 100 meters above ground level, to a height of 400 meters above sea level. This process allowed for the suppression of very shallow sources and background noise, thereby enhancing the imaging of relevant shallow magnetic sources (structures) and anomalies of interest in the residual aeromagnetic map. The 2-D geomagnetic sections developed along two section lines across the study area delineated suspected fault/ fracture zones that are characterized by low magnetic susceptibility. Euler deconvolution method was applied to the data with SI values 0.5, 1 and 2. Euler solution for structural indices and the power spectral analysis gave depth values ranging from <10-50 m for shallow sources, 50-250 m for intermediate magnetic sources and 250-770 m for deeper sources. The Euler solution for structural indices of 0.5 and 1.0 gave the best solutions. The results of this study showed that pegmatite rich rare earth mineralisation occurs as a magnetic source which exhibited low magnetic intensity at relatively shallow depth. The existence of mining sites close to the lineaments further confirms the evidence of mineralisation of some the geologic structures delineated in the study area.
Mine tremors are a significant factor contributing to safety accidents in mining areas, and studying the characteristics of the rupture process at the source of mine tremor is crucial for improving the understanding of the disaster mechanism caused by mine tremors. This paper conducts an in-depth analysis and study of 39 strong mine tremor in Shandong mining areas in China using a combination of numerical simulation and theoretical analysis. Firstly, the waveform recording of strong mine tremors is processed using Fast Fourier Transform (FFT). Subsequently, the noise term, instrument response, path effect, and site response of the monitoring station are eliminated from the waveform recording. Finally, based on the Brune source model, a genetic algorithm is utilized to fit and obtain the source parameters. The response characteristics of source parameters for strong mining tremors are analyzed, and the scale of focal rupture as well as the characteristics of regional stress release are revealed. The results showed that the calculated corner frequencies, seismic moments, moment magnitudes, and stress drops of these strong mining tremors were in the ranges of 0.9-2.6 Hz, 1012-1014 N m, 2.5-3.5, and 0.02-0.18 MPa, respectively. The results showed that the mine tremors exhibited cross-correlation relationships between the source parameters similar to those of earthquakes. This demonstrates that various source parameters of mine tremors have the same physical significance as those of earthquakes in representing the scale of focal rupture and magnitude of regional stress. However, the stress drops of strong mining tremors were orders of magnitude lower than those of earthquakes, indicating that the background stresses of the mining tremors were far smaller than those of earthquakes. This signifies that even relatively small changes in regional stress can potentially trigger the occurrence of mining tremors. We need to pay close attention to factors that can cause regional stress changes during the resource extraction process in mining areas. This provides theoretical support for the monitoring and assessment of the risk associated with strong mine tremors.
Indonesia experiences intense volcanic and tectonic activity due to its strategic location between 6 degrees N-11 degrees S latitude and 95 degrees E-141 degrees E longitude, where several major tectonic plates converge. Physiographically, Mount Pandan is located in the modern Sunda Arc region within the Anticlinorium or Kendeng Zone. Previous research recorded a minor earthquake in 2016, indicating ongoing tectonic activity in the Kendeng Zone, connected to sub-magmatic activity observed in several hot springs in Banyukuning, Jari, and Selogajah. Using gravity data, we identify the relationship between tectonic and magmatic activity through 3D inversion modelling of subsurface structures. This analysis correlates with fault fracture density (FFD) for surfaces with faults or fractures. Identifying the focal mechanism is essential for constructing the fault model of the earthquake source. The movement of Earth's crust along the Kendeng Fault influences underlying magmatic processes. Evidence of this interaction includes low-density zones and sub-magmatic features, such as the presence of hot springs. Earthquakes around the mountain with magnitudes below 4.0 SR suggest a relationship between the movement of strike-slip faults and oblique reverse faults with magma ascent. 3D inversion modelling reveals four layers: & THORN; At a depth of 0-0.46 km, with an estimated density range of 1.69-2.69 g/cm3, we interpret the layer as caprock, composed of pyroxene and host rock types. & THORN; The layer at 0.46-1.14 km, with a density range of 1.31-2.23 g/cm3, is interpreted as a reservoir containing sand and clay rock types. & THORN; Andesite and volcanic breccia rocks make up the layer at 1.14-1.59 km, with a density range of 2.4-2.8 g/cm3. It is thought to be caprock and intrusion (active fault). & THORN; We interpret the layer at 1.59-2.43 km, with a density range of 1.43-3.45 g/cm3, as a heat source with basalt rock types and magma content. These findings provide new insights into the subsurface structure and fault dynamics of the Kendeng Zone, contributing to a better understanding of tectono-magmatic interactions in seismically active regions.
On September 18, 2024, an M4.7 earthquake struck Feidong County in Hefei, Anhui Province. Located at the complex junction of the Tanlu fault zone, this event exhibited a clear foreshock-mainshock-aftershock evolution, attracting widespread attention. To investigate the aftershock activity and seismogenic structure of this earthquake sequence, this study employs deep learning methods applied to continuous waveform data from the Anhui seismic network for automatic detection. Coupled with precise earthquake relocation, a comprehensive and high-precision seismic catalog was constructed. The relocation results indicate that the Earthquake sequence are mainly distributed along a linear trend in the NE-SW direction, extending approximately 12 km, with hypocentral depths concentrated between 8 and 13 km. Notably, both the mainshock and most aftershocks occur at a depth of about 10.5 km. Focal mechanism solutions reveal that the dominant earthquakes in the region exhibit right-lateral strike-slip rupture on steeply dipping faults trending NE, which is highly consistent with the orientation and structural characteristics of the primary Zhuding-Shimenshan fault in the area. In conjunction with observational evidence of fluid intrusion, it is inferred that fluids may have migrated from the southwest into the seismogenic zone through structural pathways such as the Zhuding-Shimenshan fault and accumulated within a depth range of approximately 10 km near the fault. This fluid accumulation likely induced local stress concentration, which may be the primary trigger for the Feidong earthquake sequence.
Mine tailings are increasingly recognized as potential valuable mineral resources. This study applies magnetic susceptibility analysis to three boreholes in flotation tailings from dumps at the Pb-Zn Rudnik Mine, Serbia. The samples were obtained over a small spatial distance (10 cm), allowing for the application of various statistical methods with the obtained dataset. The results indicate that the mutual similarity among boreholes cannot be established with statistical significance; however, certain zones between boreholes exhibit some similarities. These variations are attributed to anthropogenic deposition, where local materials were intermixed and arbitrarily deposited during mining and processing, preventing clear statistical correlations. The study identifies key zones of interest in all three boreholes for further geochemical and mineralogical investigations.
In regions of low seismicity, such as Baranja in northeastern Croatia, seismic hazard assessments rely heavily on the detailed characterization of the few largest known earthquakes. This study focuses on the two strongest historical earthquakes in the area, macroseismic data from Bosnia and Herzegovina, Croatia, Hungary, and Serbia. The number of intensity observations for the earthquake of 1922 was expanded from 106 to 278, whereas the previously macroseismically not analysed event of 1924 is decribed by 14 data points. Using a modified Kövesligethy–Jánosi model that accounts for intensity anisotropy in the epicentral area, we inverted the macroseismic fields to relocate the epicentres and estimate focal depths and magnitudes. Both events were relocated near the village of Zmajevac, within the Bansko Brdo tectonic unit, close to its boundary with the Drava depression. The 1922 epicentre moved 13 km north-northeast of the original location in the which occurred on 24 November 1922 and 12 August 1924. We re-evaluated these events using newly collected Croatian Earthquake Catalogue (CEC), while the 1924 epicentre shifted 22 km westward. Revised moment magnitudes are Mwm 5.3 and Mwm 4.4 for the 1922 and 1924 events, respectively. Estimated focal depths are shallower than previously listed: 11 km and 8 km, compared to the 18 km and 14 km in CEC. These results indicate that significant seismicity in Baranja is confined to the Bansko Brdo unit, with no evidence of strong earthquakes or faults with sufficient seismogenic potential in the Drava Depression or Northern Baranja–Bačka units. This has important implications for regional seismic hazard estimates. Furthermore, we find no instrumental support for the largest catalogued aftershock of the 1922 event and propose its removal. Finally, we interpret the 1924 earthquake as a late aftershock of the 1922 mainshock, suggesting a dependent relationship between the two.
В Южной Якутии, в г. Нерюнгри, методом дистанционного индуктивного зондирования изучены особенности изменчивости в слое годовых теплооборотов эффективных значений диэлектрической проницаемости юрских песчаников, слагающих основание инженерных сооружений. В слое сезонномерзлых выветренных песчаников на глубине 0–5 м значения диэлектрической проницаемости изменяются в диапазоне 3,2–19,2 отн. ед., а в слое трещиноватых песчаников на глубине 5–14 м – в диапазоне 2,8–15,4 отн. ед. Фоновые значения диэлектрической проницаемости закономерно снижаются от 6,4 отн. ед. у сезонно-мерзлых выветренных песчаников до 4,8 отн. ед. у трещиноватых песчаников. В разнообразии изменчивости абсолютных значений диэлектрической проницаемости отчетливо проявляет себя предсказуемость относительной изменчивости ее значений в виде повторяемости в разных местах г. Нерюнгри блочного строения песчаников, которое образовалось в результате деятельности тектонических, экзогенных и криогенных процессов. Следы тектонического дробления сохраняются в трещиноватых песчаниках, но сила их физического выветривания уменьшается, что проявляется в уплотнении блочной структуры. Степень вертикального уплотнения структуры при переходе от сезонно-мерзлых выветренных песчаников на глубине 0–5 м к трещиноватым песчаникам на глубине 5–14 м равна 20–30%. Эта оценка получена на основе анализа различий фоновых значений диэлектрической проницаемости и коэффициентов ее корреляции между сезонно-мерзлыми выветренными и трещиноватыми песчаниками. In the city of Neryungri in South Yakutia, the peculiarities of variability in the annual heat turnover layer of the effective permittivity values of Jurassic sandstones forming the basis of engineering structures were studied by remote inductive sensing. In the layer of seasonally frozen weathered sandstones at a depth of 0–5 m, the values of dielectric constant vary in the range of 3.2–19.2 rel. units, and in the layer of fractured sandstones at a depth of 5–14 m – in the range of 2.8–15.4 rel. units, the background values of dielectric constant naturally decrease from 6.4 rel. units. seasonally frozen weathered sand- stones have up to 4.8 rel. units for fractured sandstones. In the variety of variability of the absolute values of the dielectric constant, the predictability of the relative variability of its values is clearly manifested in the form of the repeatability in different places of Neryungri of the block structure of sandstones, which was formed as a result of tectonic, exogenous and cryogenic processes. Traces of tectonic crushing remain in fractured sandstones, but the force of their physical weathering decreases, which is manifested in the compaction of the block structure. The degree of vertical compaction of the structure during the transition from seasonally frozen weathered sandstones at a depth of 0–5 m to fractured sandstones at a depth of 5–14 m is 20–30%. This estimate was obtained based on the analysis of differences in the background values of the dielectric constant and its correlation coefficients between seasonally frozen weathered and fractured sandstones.
В статье представлены результаты комплексного исследования зон фокусированной разгрузки флюидов (ЗФР) в северо-восточной части Восточно-Сибирского моря. Восточно-Сибирское море, являясь мелководным окраинным морем Северного Ледовитого океана, обладает сложным геологическим строением и характеризуется наличием зон интенсивной разгрузки на морское дно глубинных флюидов, связанной с разломами и ослабленными зонами. Исследования проводились с использованием комплекса геофизических и литолого-геохимических методов. В ходе работ исследовали пять площадок, в пределах которых выявлены области разгрузки флюида с аномально высокими концентрациями метана термогенного происхождения. Кроме того, полученные данные косвенно указывают на возможное наличие многолетнемерзлых пород в регионе. Результаты исследования имеют важное значение для характеристики современных процессов в ВЧР и оценки углеводородного потенциала бассейна. The article presents the results of a complex research of focused fluid discharge zones in the north-eastern part of the East Siberian Sea. The East Siberian Sea, being a shallow marginal sea of the Arctic Ocean, has a complex geological structure and is characterised by the presence of zones of intensive discharge of deep fluids to the seabed associated with faults and weakened zones. The studies were carried out using a set of geophysical and lithological-geochemical methods. During the works five sites were investigated, within which the areas of fluid discharge with anomalously high concentrations of methane of thermogenic origin were revealed. In addition, the data obtained indirectly indicate the possible presence of permafrost in the region. The results of the study are important for characterising the current processes in the upper part of the section and assessing the hydrocarbon potential of the basin.
Для строительства объектов донной инфраструктуры и безопасного бурения на шельфе необходимо проводить геолого-геофизические исследования, целью которых является изучение верхней части разреза и обнаружение опасных геологических процессов. В рамках данной работы была выполнена специализированная обработка поверхностных волн, полученных при проведении морских работ МОВ ОГТ 3D, по технологии MASW (Multichannel Analysis of Surface Waves) с применением нейронных сетей с целью детального изучения верхней части разреза шельфа Печорского моря. В результате выполненной работы удалось показать эффективность применения нейронных сетей для обработки большого количества сейсмических данных, позволивших повысить разрешение моделей скоростей поперечных волн; подобрать оптимальную архитектуру нейронных сетей, а также выработать методику обучения моделей; уточнить положение некоторых типов опасных геологических процессов и явлений (палеоврезов, грубообломочных отложений) и получить дополнительную информацию об их свойствах и глубинном положении. For the construction of bottom infrastructure facilities and safe drilling on the shelf, it is necessary to conduct geological and geophysical studies aimed at studying the upper part of the section and detecting geohazardous processes. Within the framework of this work, specialized processing of 3D standard marine seismic data was performed using MASW (Multichannel Analysis of Surface Waves) technology using neural networks in order to study in detail the upper part of the section of the Pechora Sea shelf. As a result of the work done, it was possible to demonstrate the efficiency of using neural networks for processing a large amount of seismic data, which made it possible to increase the horizontal resolution of shear wave velocity models; select the optimal architecture of neural networks, and develop a methodology for training models; clarify the position of some types of geohazardous processes (paleoincisions, coarse-grained sediments) and obtain additional information on their properties and depth position.
Показана возможность расчета полного сейсмического волнового поля методом спектральных элементов для детальных объемных цифровых моделей среды, построенных в программах геологического моделирования Petrel или в аналогичных. Учитываются все типы волн, возникающих в среде: продольные, поперечные, поверхностные, обменные, дифрагированные, в отличие от упрощенных сверточных и лучевых схем, применяемых в настоящее время и зачастую дающих результаты, приводящие к ошибочным выводам. Основой разработки послужили передовые теоретические и прикладные решения, полученные группой ученых МГУ им. М.В. Ломоносова в рамках созданного ими программного обеспечения «Фидесис». Вычисления производились на новом суперкомпьютере «МГУ-270», одном из самых мощных в России, с использованием передовых параллельных вычислительных технологий для гибридных высокопроизводительных систем. The study demonstrates the feasibility of modeling the full seismic wavefield using the spectral element method for detailed 3D digital subsurface models constructed in geological modeling software (Petrel or similar). The approach accounts for all wave types generated in the medium: compressional, shear, surface, converted, and diffracted waves, unlike simplified convolutional and ray-based schemes currently employed, which often yield misleading results. The development leverages advanced theoretical and applied solutions from Lomonosov Moscow State University's research group, implemented in their proprietary software "Fidesys." Computations were performed on the "MSU-270" supercomputer, one of Russia's most powerful systems, utilizing state-of-the-art parallel computing technologies for hybrid high-performance architectures.
Представлены результаты изучения гравитационных процессов в Черноморской впадине по данным мультичастотного сейсмоакустического профилирования, гидролокации бокового обзора и многолучевого эхолотирования. Рассмотрены примеры проявления на сейсмоакустических разрезах отложений подводных оползней и гравитационных потоков. Особое внимание уделено интерпретации данных, полученных с использованием автономного необитаемого подводного аппарата в глубоководной зоне моря. The results of studying gravity processes in the Black Sea basin based on data from multifrequency continuous seismic profiling, sidescan sonar, and echo sounding are presented. Examples of the occurrence of underwater landslides and gravity flows on seismic acoustic sections of sediments are considered. Special attention is paid to the interpretation of data obtained using an autonomous uninhabited underwater vehicle in the deep-sea zone.
В статье обосновывается важность опережающего изучения строения верхней части разреза на шельфе до начала инженерно-геологических изысканий с целью выявления опасных геологических процессов и явлений для бурения. Основой работ является методика специальной обработки и интерпретации стандартных данных сейсморазведки 2D и 3D для решения инженерных задач. Предложенные подходы позволяют выявлять аномалии в сейсмическом разрезе для их дальнейшей идентификации и ранжирования по степени опасности для хозяйственной деятельности. Понимание инженерно-геологических условий района необходимо для нескольких задач: во-первых, для оценки рисков постановки буровой установки, безопасного бурения скважин и возможностей обустройства шельфовых месторождений, в том числе оптимизации выбора участков для детальных инженерно-геологических изысканий, методов и объемов работ на предварительном этапе; во-вторых, для регионального изучения геологического строения верхней части разреза; d-третьих, для территориального планирования инженерно-геологических изысканий. Авторы подчеркивают как геологическую, так и экономическую целесообразность и эффективность предлагаемого подхода, подтвержденные исследованиями на отдельных участках шельфа. This article substantiates the importance of preliminary studies of the shallow subsurface structure on the continental shelf prior to engineering and geological surveys for drilling, with the goal of identifying hazardous geological processes and features. The approach is based on a methodology for specialized processing and interpretation of standard 2D and 3D seismic data, aimed at solving engineering-related problems. The proposed methods enable the detection of anomalies in seismic sections and their subsequent classification of hazard they pose to industrial operations. Understanding the engineering and geological conditions of the study area serves multiple purposes: first, to assess the risks associated with rig installation, well drilling, and the development of offshore fields—including the optimization of locations for detailed geotechnical investigations, and the selection of methods and volumes of work in the early planning stages; second, to support the regional study of shallow subsurface geological structures; and third, to aid in spatial planning of offshore territories. The authors emphasize both the geological and economic feasibility of the approach, which has been validated through research conducted in selected shelf areas.
В данной статье описываются основные подходы к использованию данных комбинированной аэроэлектроразведочной системы для решения обратных задач. Разработаны алгоритмы решения стохастической задачи оценивания параметров горизонтально-слоистой среды при помощи итерационного обобщенного фильтра Калмана. Они позволяют комбинировать параметры отклика во временной и в частотной областях и уменьшить степень неоднозначности решения обратной задачи. This article describes the main approaches of using combined airborne electromagnetic data to solve inverse problems. Algorithms for solving the stochastic problem of estimating the parameters of a horizontally layered medium using an iterative extended Kalman filter have been developed. They allow combining response parameters in the time and frequency domains and reducing the ambiguity degree in the solution of the inverse problem.
Представлены новые экспериментальные результаты, впервые демонстрирующие возможности уверенно регистрировать при проведении ВСП на оптоволоконном кабеле волны разных типов, используемые в многоволновой сейсморазведке. Показано, что при надежном контакте кабеля со стенкой скважины на не продольных вертикальных профилях преобладают обменные волны, интенсивность которых может превышать интенсивность продольных отраженных волн. Приведены разрезы, полученные путем миграции записей ВСП с выделенными обменными отраженными волнами. New experimental results are presented, demonstrating for the first time the possibility of detecting waves of various types used in multi-wave seismic exploration during VSP operations on fiber-optic cables. It is shown that with reliable contact of the cable with the borehole wall, converted waves prevail on offset vertical profiles, the intensity of which may exceed the intensity of compressional reflected waves. The crosssections obtained by migration of VSP records with selected converted reflected waves are presented.
