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This study investigates the variations in stress, strain, and deformation of the Earth's crust in Iran arising from tectonic movements and seismic activities. We employed the Kostrov and Molnar methods to quantify these parameters, focusing on the influence of different zoning techniques on the estimations. Analyzing data from 637 earthquakes (moment magnitudes > 5.5) spanning 1909 to 2016, we determined the directions of maximum pressure, tension, and seismic strain through two primary approaches: comprehensive zoning and individual earthquake analysis. Additionally, we assess horizontal shortening and vertical crustal adjustments. Our methodology involves three distinct strategies: individual earthquake analysis, 1° x 1° zoning, and tectonic zoning. The findings demonstrate that the choice of zoning method significantly affects the direction and magnitude of seismic strain estimations. Although both methods identified significant deformations in the Dasht Bayaz and Qaen regions of Eastern Iran, differences between the Kostrov and Molnar methods in estimating seismic strain are observed. The high Zagros region shows signs of crustal thickening, whereas the Zagros foreland exhibits crustal thinning. Intriguingly, Eastern Alborz indicates uplift, and Western Alborz suggests subsidence, offering an alternative view to the conventional tectonic understanding of the Alborz range. These results highlight the critical role of zoning in stress analyses and the disparities between widely used estimation techniques. They underscore the necessity of careful method selection and interpretation in geodynamic studies, particularly in seismically active regions like Iran. [ABSTRACT FROM AUTHOR]

This study investigates the variations in stress, strain, and deformation of the Earth’s crust in Iran arising from tectonic movements and seismic activities. We employed the Kostrov and Molnar methods to quantify these parameters, focusing on the influence of different zoning techniques on the estimations. Analyzing data from 637 earthquakes (moment magnitudes > 5.5) spanning 1909 to 2016, we determined the directions of maximum pressure, tension, and seismic strain through two primary approaches: comprehensive zoning and individual earthquake analysis. Additionally, we assess horizontal shortening and vertical crustal adjustments. Our methodology involves three distinct strategies: individual earthquake analysis, 1° × 1° zoning, and tectonic zoning. The findings demonstrate that the choice of zoning method significantly affects the direction and magnitude of seismic strain estimations. Although both methods identified significant deformations in the Dasht Bayaz and Qaen regions of Eastern Iran, differences between the Kostrov and Molnar methods in estimating seismic strain are observed. The high Zagros region shows signs of crustal thickening, whereas the Zagros foreland exhibits crustal thinning. Intriguingly, Eastern Alborz indicates uplift, and Western Alborz suggests subsidence, offering an alternative view to the conventional tectonic understanding of the Alborz range. These results highlight the critical role of zoning in stress analyses and the disparities between widely used estimation techniques. They underscore the necessity of careful method selection and interpretation in geodynamic studies, particularly in seismically active regions like Iran.

The Jurassic strata constitute a focal area for recent exploration and development of tight gas reservoirs in the western Sichuan Basin. This study investigates the Jurassic Shaximiao Formation in the northern Longmenshan in the Western Sichuan basin, focusing on tight gas reservoirs. The research integrates core and outcrop observations, seismic interpretations, and burial history analyses to understand hydrocarbon source rocks, sedimentation, reservoir characteristics, and structural characteristics. The impact of Yanshan-Himalayan tectonic movements on tight gas reservoir accumulation in the Shaximiao Formation is dissected, primarily around the Qiulin structure. The Western Sichuan Depression basin's formation is influenced by gravitational gliding tectonics, which can be classified into the 'Three Zones and One Belt,' with Longmenshan in the frontal belt. Burial history analysis reveals distinct processes in the foreland belt and the depression basin. In the Qiulin area, gas reservoirs in the Shaximiao Formation are mainly charged by source rocks from the Xujiahe Formation. Tectonic movements play a significant role in creating favorable reservoirs and conditions for hydrocarbon migration and preservation. Natural gas accumulation is primarily controlled by fault connectivity to hydrocarbon sources and effective reservoir thickness. Gravitational sliding tectonics have shaped a fluvial-lacustrine environment for the Shaximiao Formation, with fluvial sand bodies acting as favorable reservoir zones. Small-scale normal faults formed by tectonic movements serve as conduits for natural gas migration. The research findings are of significant guidance for the exploration and development of tight oil and gas resources in western Sichuan basin. [ABSTRACT FROM AUTHOR]

Climatic and environmental conditions play a pivotal role in the evolution of the biosphere, serving as the primary natural factors influencing biological evolution and the development of human civilization. The study of the evolution of Earth's habitability primarily revolves around the reconstruction of climatic and oceanic conditions in geohistorical periods, shedding light on their dynamic changes. This paper collates classic geological indicators and geochemical proxies associated with paleo-climatic and oceanic environmental conditions. The latest "big data" analyses and simulations made possible by the availability of previously unimagined massive datasets reveal several key findings: During the early Paleozoic, atmospheric oxygen levels were low, and widespread oceanic anoxia was prevalent; the Devonian era witnessed a greenhouse climate, followed by the Carboniferous ice age characterized by higher oceanic oxidation levels and alkalinity. The latest Paleozoic deglaciation occurred under high pCO2 conditions, extending into much of the Mesozoic and early Cenozoic, marked by multiple hyperthermal and anoxia expansion events, until the resurgence of global glaciation in the middle-late stages of the Cenozoic, ultimately bringing environmental and climatic conditions closer to modern levels. By correlating the aforementioned long-term trends with major geological events, we can delineate the co-evolution of paleoclimate and oceanic environments in tandem with the development of Tethys tectonics as follows. (1) During the Proto-Tethys stage, global paleo-elevations were relatively low, and atmospheric oxygen levels were also relatively modest. Despite the occurrence of significant tectonic movements that led to noticeable transgressive-regressive cycles, their effects on climate and oceanic environments were somewhat limited due to the relatively weak interactions. (2) The emergence of the Paleo-Tethys was a significant event that coincided with the formation of the supercontinent Pangaea. Intensive orogenic movements during this period increased the global land area and elevation. This, in turn, led to enhanced terrestrial weathering, which elevated sea surface productivity and resulted in massive nutrient input into the oceans. Consequently, this process contributed to the rise of oxygen levels in the atmosphere and a decrease in atmospheric pCO2. These changes are considered potential driving mechanisms for late Paleozoic glaciation and oceanic oxygenation. (3) The transition from the Paleo-Tethys to the Neo-Tethys was closely linked to the breakup of Pangaea. During this period, the terrestrial weathering processes were relatively weak due to decreased continental elevations. This resulted in a long-term greenhouse climate and intermittent global oceanic events, which were responses to the high atmospheric pCO2 levels during the Mesozoic and early Cenozoic eras. (4) The Neo-Tethys stage ended with the dramatic uplift of the Alps-Himalaya Mountain ranges due to the collision of India and Asia. This uplift had a profound global impact, significantly increasing continental elevations. As a result, weathering and carbon burial processes intensified, leading to a reduction in atmospheric pCO2. Concurrently, this uplift played a crucial role in the establishment of the East Asian monsoon and North Atlantic deep-water circulations, both of which played a part in triggering the late Cenozoic ice age. These models suggest that the teleconnections between land and sea (orogeny-terrestrial weathering-marine carbon burial) span over the whole Phanerozoic and might have played a key role in balancing the Earth surface system. Combined, the tectonic, volcanic, paleo-climatic, as well as paleoenvironmental events recorded in the Tethys oceans and adjunct continents represent valuable natural experiments and lessons for understanding the present and the future of Earth's habitability. [ABSTRACT FROM AUTHOR]

The Jurassic strata constitute a focal area for recent exploration and development of tight gas reservoirs in the western Sichuan Basin. This study investigates the Jurassic Shaximiao Formation in the northern Longmenshan in the Western Sichuan basin, focusing on tight gas reservoirs. The research integrates core and outcrop observations, seismic interpretations, and burial history analyses to understand hydrocarbon source rocks, sedimentation, reservoir characteristics, and structural characteristics. The impact of Yanshan-Himalayan tectonic movements on tight gas reservoir accumulation in the Shaximiao Formation is dissected, primarily around the Qiulin structure. The Western Sichuan Depression basin’s formation is influenced by gravitational gliding tectonics, which can be classified into the ‘Three Zones and One Belt,’ with Longmenshan in the frontal belt. Burial history analysis reveals distinct processes in the foreland belt and the depression basin. In the Qiulin area, gas reservoirs in the Shaximiao Formation are mainly charged by source rocks from the Xujiahe Formation. Tectonic movements play a significant role in creating favorable reservoirs and conditions for hydrocarbon migration and preservation. Natural gas accumulation is primarily controlled by fault connectivity to hydrocarbon sources and effective reservoir thickness. Gravitational sliding tectonics have shaped a fluvial-lacustrine environment for the Shaximiao Formation, with fluvial sand bodies acting as favorable reservoir zones. Small-scale normal faults formed by tectonic movements serve as conduits for natural gas migration. The research findings are of significant guidance for the exploration and development of tight oil and gas resources in western Sichuan basin.

The studied rock collapse structure is located on the Liburnian coast (Rijeka Bay, channel zone of the NE Adriatic). The relief of the southern part of this coast, with a length of 6.5 km, is a large escarpment with very steep to vertical slopes reaching heights of 100 m above sea level, as a result of tectonic movements along the Kvarner fault zone. These events probably led to a sudden relaxation of the highly fractured rock mass. The progressive expansion occurred at locations where previously favourably oriented faults and fissures had formed a polygonal rock collapse resembling a rock-slide which is the focus of this study. Another aim of this study is to reconstruct and explain the complex morphological evolution of the studied landslide, from the pre-failure deformations, through the failure itself, to post-failure displacements, as well as possible future instabilities. Recent techniques to survey the instability, location and to analyse the evolution of the rupture surface and its dimensions were combined (Unmanned Aerial Vehicle, Side Scan Sonar and Remotely Operated Vehicles). The estimated total volume of displaced rock mass is 950,000 mi The lower part of the instability phenomenon was submerged during the Holocene sea level rise. Since then, a large part of the displaced rock mass has been in a stable position, with sporadic rock falls. However, given unfavourable orientation and discontinuity characteristics, as well as unfavourable environmental influences, possible instabilities might also be expected in the future. [ABSTRACT FROM AUTHOR]

Landslides are a significant global risk due to their impact on nature, society, and the economy. The Al Hoceima-Ajdir region is highly susceptible to geohazards such as earthquakes and ground instabilities caused by local tectonic movements and specific climatic and geomorphological conditions. This study aims to assess landslide susceptibility in Al Hoceima-Ajdir using a digital mapping approach that integrates the geostatistical Frequency Ratio tool, geomatic tools, and field observations. The frequency ratio method, a widely used technique in geospatial analysis, evaluates the relative frequency of landslides based on the spatial distribution of conditioning factors such as slope, lithology and land use – land cover. This method calculates the ratio of the frequency of landslides within specific classes of these factors to their respective frequencies in the entire study area. This research introduces a novel susceptibility map highlighting major threats to several natural and touristic sites crucial to the region's socio-economic activities. The susceptibility map was developed by analyzing 40 historical landslides along various predisposing factors, including topographic, geo-hydrological, and anthropogenic parameters. The results identify areas prone to landslides and classify their susceptibility into five levels ranging from very high to very low, with each level indicating a different degree of risk and requiring a specific set of preventive measures. The reliability of this map was evaluated using the Receiver Operating Characteristics (ROC) method, demonstrating a high accuracy of 89%, further validated by field visits. This high-precision susceptibility map is significant for pre- and post-risk management, enhancing prevention and mitigation strategies. It also protects society, the economy, and the environment by providing a reliable regional planning and hazard management tool. The findings of this study offer a significant advancement in the methodology for landslide susceptibility assessment and present a model that can be adapted to other regions facing similar geohazards. The research underscores the importance of integrating geostatistical tools with field data to produce accurate and actionable susceptibility maps, benefitting the global scientific community by improving hazard prediction and management strategies. • Spatial-temporal reconstruction of rainfall and land use changes in El Ganzra, Morocco. • LME model predicts precipitation and land use changes up to 2050. • Kappa coefficient of 0.80 indicates high model reliability. • Predicted a decrease in annual cumulative precipitation by 11.4% in the region from 1985 to 2050. • Loss of forest land & water bodies contribute to irregular annual rainfall. [ABSTRACT FROM AUTHOR]

The Wufeng-Longmaxi (WL) shale is widely distributed in the Sichuan Basin and adjacent areas in southwest China. The basin experienced multiple-stage complex tectonic movements, whose influences on burial, thermal maturation and gas generation histories in different areas are poorly understood. Based on a detailed study of the denudation stages, strata thickness, and thermal history of the basin, burial and thermal maturation histories of seven wells in different areas were modelled using PetroMod software. Due to the high maturity of the WL shale, a low-maturity Silurian Polish Llandovery shale was used for gold tube closed-system pyrolysis experiments to obtain kinetic parameters for evaluating methane generation history. The Polish shale was selected due to its depositional age, sedimentary environment and organic type, which are similar to the WL shale. The burial history of the WL shale can be divided into five stages: I. Early to Middle Silurian rapid burial; II. Caledonian uplift and denudation; III. Permian to Triassic sustained burial and denudation; IV. sustained burial since the Late Triassic; and V. Late Cretaceous to present sustained uplift and denudation. The thermal maturity of the WL shale in all wells increased with burial depth during stage IV. In addition, high calculated reflectance increments in wells JY1 and N201 during stage III occurred due to the relatively high basal heat flow and deep burial depth, resulting in higher current thermal maturities than in the other wells. The late Permian–Early Triassic and the Middle Jurassic–Early (or Late) Cretaceous were the key methane generation periods for wells JY1 and N201. In contrast, the other five wells had a single methane generation stage, mainly determined by burial and thermal maturation processes. The time of uplift and the amount of denudation during stage V, the current burial depth, the development of faults and fractures, high proportion of retention and the seal capacity of the overlying caprock are key factors for shale gas preservation. Hence, this study will help guide future shale gas development in the Sichuan Basin. • Burial, thermal maturation and gas generation histories of seven wells in different areas of the Sichuan Basin were modelled. • Methane generation histories were reconstructed by kinetic parameters from the Lower Silurian Llandovery shale. • Influences of tectonic evolution processes on burial, thermal maturation and gas generation histories were evaluated. • Main controls on shale gas preservation, such as timing of uplift, denudation and burial depth, were studied. [ABSTRACT FROM AUTHOR]

In this study, data of dipole electric sounding of the earth's crust in the area of the high-altitude dam of the Chirkey Hydropower Plant (HPP) are analyzed to identify "hidden" tectonic faults in the region. It is recommended to conduct monitoring investigations using the dipole sounding method, to identify geodynamically active fault zones, while selecting a dam construction site. [ABSTRACT FROM AUTHOR]

Recently, the establishment of Continuously Operation Reference Stations (CORS) networks has been fundamental for Global Navigation Satellite Systems (GNSS)-based geomatics activities worldwide. The Egyptian Surveying Authority (ESA) established a CORS network in 2011 adjusted to the International Terrestrial Reference Frame (ITRF) ITRF2008 (epoch 2011.8096). CORS networks' coordinates must be updated regularly to remain consistent with the latest reference frame realization, so this study aims to update the ESA CORS network to the ITRF 2014 (epoch 2019.5833) reference frame, analyze the coordinates' changes, and determine the positional directions and velocities because of tectonic movements over 2011-2019. Results show that the 2D and 3D coordinate discrepancies during that time have averages of 0.237 m and 0.253 m, respectively. Furthermore, the average direction of horizontal movements is 55.4°, and the overall 2D and 3D regional velocities are 29.7 and 31.7 mm/year, respectively. Therefore, the tectonic movements in Egypt, over the last decade, should be considered in GNSS high-accuracy geomatics activities. In addition, the developed ITRF coordinates-conversion produced accuracy in the order of 1-2 cm. Therefore, we suggest this conversion model is appropriate for GNSS surveying applications in Egypt. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA cytochrome b and d-loop sequences (2,137 bp) in 65 specimens of Sarcocheilichthys sinensis from five populations were identified as two lineages (I and II). The pairwise genetic distance between lineages I and II was 1.94%. SAMOVA analyses suggested that the best grouping occurred at three groups, Yangtze, Qiantang and Minjiang Rivers. High haplotype diversity (0.949) and low nucleotide diversity (θπ = 1.067%) were detected. The results of the neutrality tests, mismatch distribution and approximate Bayesian computation (ABC) did not support demographic expansions. The results of phylogenetic analysis, statistical dispersal-vicariance analysis (S-DIVA), ABC, MIGRATE-N and the time to the most recent common ancestor (TMRCA) indicated two colonization routes. First, before the Wuyi Mountains lifted, S. sinensis dispersed from the Yangtze River to the Minjiang River. Second, during glaciation, the continental shelf was exposed, which contributed to the dispersion of populations from the Yangtze River. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA cytochrome b sequences (1141 bp) in 229 specimens of Acrossocheilus paradoxus from 26 populations were identified as four lineages. The pairwise genetic distances among these four lineages ranged from 1.57 to 2.37% (mean=2.00%). Statistical dispersal-vicariance analysis suggests that the ancestral populations were distributed over mainland China and Northern and Western Taiwan. Approximate Bayesian computation approaches show that the three lineages in Taiwan originated from the lineage in mainland China through three colonization routes during two glaciations. The results indicated that during the glaciation and inter-glacial periods, the Taiwan Strait was exposed and sank, which contributed to the dispersion and differentiation of populations. Furthermore, the populations of A. paradoxus colonized Taiwan through a land bridge to the north of the Formosa Bank, and the Miaoli Plateau in Taiwan was an important barrier that limited gene exchange between populations on both the sides. [ABSTRACT FROM AUTHOR]

The prospects of identification of gas hydrate deposits within the Black Sea are considered in the work. The areas are described that contain gene-fluids structures which are associated the methane-hydrated deposits. The promising areas for the searches for gas-hydrates deposits within the Black Sea are grounded. We consider the theory of their formation and existence under certain thermodynamic conditions. Attention is drawn to the area located on the continental slope in the north-western Black Sea. It is suggested that the relationship of mud volcanoes and gas hydrates with thermal diapir has paragenetic nature, and their relationship with the thermal diapir is genetic.

The north and south Moluccas (Indonesia) have very different geotectonic origins and, due to that, a difference in flora is to be expected. The north Moluccas moved westwards along the north coast of New Guinea to their present position, the south Moluccas moved north from Australia. On the other hand, a comparable climate in both areas and (partial) submergence during tectonic movement may have equalized both floras. Collection data from Naturalis Biodiversity Center on 1559 species in 121 families treated in Flora Malesiana were collected for the Moluccas, Sulawesi, and Western New Guinea (latitudes 9.2°S and 5.6°N and longitudes 118.8°E and 141°E) and georeferenced. Species Distribution Models (SDMs) were made, based on least correlated climate and edaphic variables, using only those species that were present in 5 or more grid cells of 5‐arc minutes and models were tested for deviation from random. Both areas differ significantly and share only 50%–65% of their species. The 348 significant SDMs differ much less, though still significantly, sharing 91% of the species. Despite strong climatic and edaphic similarities between the North and South Moluccas, they differ greatly in species composition, which is in support of geotectonic reconstructions. The differences between the North and South Moluccas suggest that the continuous dispersal barriers and tectonic backgrounds have influenced their current flora. [ABSTRACT FROM AUTHOR]

Ratawi Field is a promising hydrocarbon bearing structure conforming several reservoirs, and lies northwest of the Basrah city and west of Northern Rumaila Field. Kinetic Analysis referred to that the type of Fold of Ratawi Structure similar to the types which are associated with Salt Structure activity.Geophysical Interpretation referred to the presence of Salt Structure beneath Ratawi Structure. The Isopach Maps shows that the crest thickness is less than the limbs, this characteristics is always due to those of salt structures beneath Ratawi field. Both of Tectonic Movement and Salt Structure play a great role in forming and development of Ratawi Structure. [ABSTRACT FROM AUTHOR]

Earth subsidence has been one of the important issues jeopardizing environment and there are many studies, which blame shortage of underground water resources for having uplift and subsidence. However, many argue such conclusion and believe that earth subsidence has been studied in the past without considering the changes in the hill over a long period. In this study, we use SAR interferometry study to investigate earth subsidence in dessert areas of Esfahan, Yazd and Ardakan, located in central part of Iran. The results indicate that there are more important issues affecting subsidence such as the uplift in the hills located the desert area. The results of the survey based on SAR interferometry reveals that subsidence occurs with the uplift in the adjacent hills, simultaneously. In other words, tectonic movements and soft isostasy play important role on earth subsidence.

Monitoring of tectonic movements along two active faults of Dinaric (NW-SE trending) fault system in W Slovenia using TM 71 extensiometers was set up in 2004. After two years ob measurements some clear trends of displacement were developed. The average left-lateral displacement along a crack in the inner fault zone of the Idrija fault in Učja valley is 0.38 mm/year. Short term (10 months) rates were even greater and reached the value of 0.54 mm/year. Since the Idrija fault is considered as dextral strike-slip, is the observedleft-lateral displacement explained by local permutation of principle stress axis. In the Ra{a fault monitoring site at the foot of Vremščica Mt. at Košana the average reverse uplift of hanging wall (SW) block of 0.24 mm/years and left-lateral displacement of 0.16 mm/year were established. Short term (9 months) vertical displacements reached the value of 0.53 mm/year. The oblique sense of displacement is in agreement with geological and seismological observations. Since there were no stronger earthquakes in the vicinity and time span of monitoring, no correlations were established with seismic activity. The observed displacement rates along monitored faults of up to 0.5 mm/year are consistent with the regional deformation rate in W Slovenia established from GPS measurements which is of the order of 2 mm/year.

The genus Opsariichthys is an endemic and widespread cyprinid genus in East Asia, but the speciation and differentiations are still unknown. This study examined the phylogeography of the genus Opsariichthys using mitochondrial DNA cytochrome b sequences (1140 bp) with extensive sampling throughout its distribution range. In total, 444 specimens belonging to seven Opsariichthys species were collected from 43 populations. The time coalescing to the genus Opsariichthys could be traced back to the late Miocene [T MRCA = 6.43 mya (million years ago)]. The interspecies differentiations occurred in two phases, Pliocene (>2 mya, Opsariichthys uncirostris , Opsariichthys bidens , Opsariichthys evolans , Opsariichthys kaopingensis and Opsariichthys pachycephalus ) and Pleistocene (<2 mya, Opsariichthys minutus and Opsariichthys hainanensis ). The results of a statistical dispersal-vicariance analysis suggested that the ancestral populations of the genus Opsariichthys were widely distributed over East Asia before diversification. Our study showed that the cyclic tectonic movements and climate changes may have shaped speciation, migrations and population differentiations. Moreover, our study considered the colonization times and migrating potentiality that could affect the Opsariichthys species’ distribution ranges and intraspecific genetic variation patterns. [ABSTRACT FROM AUTHOR]

The Vyhne Tidal Station of the Earth Science Institute of the Slovak Academy of Sciences is located in the former mining gallery of St. Anthony of Padua in the Vyhne valley, Stiavnicke vrchy Mts., Central Slovakia. It is equipped with a 20.5 metre long quartz-tube extensometer measuring Earth's tides, and long-term tectonic deformations of the Earth's crust. Data between 2001 and 2015 with some diverse gaps were digitally collected, processed and analysed. The effects of the local conditions, such as structure of the observatory, cavity effect, topography and geological features of the surrounding rocks, were investigated in detail and these effects were taken into consideration during the interpretation of the results of the data analysis. Tidal analysis of the extensometric data between 2005 and 2015 revealed that the measured tidal amplitudes are close to the theoretical values. The tidal transfer of the observatory was also investigated by coherence analysis between the theoretical and the measured extensometric data. The coherence is better than 0.9 both in the diurnal and semidiurnal band. The effect of the free core nutation resonance was also investigated in the case of the K1 and P1 tidal components. Since the K1/O1 ratio was about the theoretical value 0.8, than the P1/O1 was between 1.0 and 1.15 instead of the theoretical value of 0.9. The rate of the long-term strain rate was also investigated and the obtained -0.05 str/y shows a good agreement with the strain rate inferred from GPS measurements in the Central European GPS Reference Network. [ABSTRACT FROM AUTHOR]

In general, the evolution of fluvial systems in Central-Eastern Europe reflects the main phases of climatic changes during the period of 60–8 ka cal BP registered in Greenland ice cores and their isotopic 18 O curves. The Greenland isotope curve shows many more wiggles and stages than the fluvial record of the same time, especially during the Interpleniglacial phase. In Central-Eastern Europe, we observe several deviations from those climatic trends, connected with different factors, among which are the long distance of the region from the Atlantic Ocean and an increase in continentality. At times, this region was occupied by permafrost although the coexisting warm summers during a part of the studied period enabled the presence of a forest cover. These factors together controlled the specific features of the fluvial regime and sediment load reflected in alternating trends to erosion or aggradation and from meandering to braiding. The permafrost influenced snowmelt floods and tendency to braiding. The dense vegetation (with trees) reduced the supply of sediments and stabilized the meandering channels. Very distinct changes occurred in the river valleys that drain the mountains, where ceaseless fluctuations of vegetation vertical zones were present, especially during the unstable Interpleniglacial when the supply of load from the higher vegetation zones was increased. This system, controlled by the climate and plant vegetation, was modified by other factors including tectonics, wind activity during dry periods, blocking of valleys by ice sheets, meltwater supply, and sea level fluctuations of two reservoirs. [ABSTRACT FROM AUTHOR]

A permanent seismotectonic activity is present in the region of northern Velebit. Through history a number of earthquakes magnitudes of VIII° and IX° MCS are reported. In this century the most powerful earthquake of a magnitude of 5.8 occurred in 1916. The key tectonic movements that cause these earthquakes are dislocations of the Adriatic platform towards the north and the resistance of the Dinarides towards these movements. The tectonic dynamics of a structural arrangement depend on the relationship between stress and the deformation of structural units. According to the tectonic measurements performed on outcrops of major faults the following orientation of stress was obtained: from 20/25° to 200/205° in the northern Velebit region and 340 to 160° in the hinterland. Within the structural arrangement compression of space occurs which is well pronounced in the Novi Vinodolski area. Possible deformation of structures is manifested spatial diagonal reverse displacements accompanied by rotation of the structure. In the Velebit hinterland right horizontal tectonic transport was determined. In the zone of the transcurrent faull Žuta Lokva-Otočac-Bunić the spatial opening leads to the formation of pull-apart structures. Seismotectonically active zones occur in the contact region between the Adriatic platform and the Dinaridcs. Spatially its position is inclined and bent.

The construction design of the underground hydroelectric plant Ombla required geological and structural investigations to he carried out. Due to past earthquakes in the area permanent tectonic movements were inferred. Therefore, in the wider and adjacent surroundings of the Ombla spring it was necessary to analyze the structural fabric and the geodynamic characteristics of the area. The most active zone encountered is the front part of a thrust fault belonging to the Dinaricum regional structural unit. The compressive regime is maintained as a response to the regional stress of an approximately S-N orientation. Different displacements of various parts of the Dinaricum unit are present. Along the rim of the structural blocks, the Hum-Om-bla fault zone extends, accompanied by left transcurrent faults, Through this zone the main groundwater drainage occurs supplying the Ombla spring. In the local Ombla spring area this zone is characterized by three sub-blocks and three major faults. The most important fault for the vital facilities of the Ombla hydroelectric power plant is the Pločice fault which divides the structural sub-blocks. Along this fault zone there are four mutually connected. The lowest two arc active groundwater draining systems supplying the Ombla spring. The data on local stress implies the following deformation of sub-blocks: sub-blocks 2c and 2f are displaced along normal faults from 20° to 30° to the left, downwards, while the sub-block 2 d is displaced along the Pločice thrust fault of 100° to 130° to the left, upwards. The structural data confirmed that the building of an underground dam with a height from 100 to 130 m was feasible. The connection between the caverns and the fault zone was determined. The unfavorable position of the active Pločice fault zone imposes the construction of vital Ombla power plant facilities underground.

Three hundred eighty-six oriented block samples were collected from the lower 334 m of Pliocene and Pleistocene fluvial strata of the Shungura Formation in two field seasons. Paleomagnetic polarity of these was determined on samples from these blocks, using a routine of 8-13 steps for AF demagnetization, and 15-20 steps for thermal demagnetization. Rock magnetic properties revealed titanomagnetite with subordinate maghemite as the dominant magnetic minerals with pseudo-single domain magnetic grain sizes. Directional analyses indicate one or two components of magnetization both in AF and thermal techniques. The first component is mostly removed by 5-10 mT AF fields or heating to 300 °C. The magnetization component after these steps generally defined straight-line segments directed towards the origin which are interpreted as the Characteristic Remanent Magnetization (ChRM). ChRM directions so determined and averaged at the site level revealed both normal and reversed polarities. The directions of the normal and reversed polarities are respectively Dec = 357°, Inc = -0.1 (N = 36, α95 = 3.7°) and Dec = 176°, Inc = -3.4 (N = 55, α95 = 3.1°) and are antipodal. A sequence of R4-N3-R3-N2-(R2)-N1-R1 polarities was identified with R2 being an anomalous direction within N2/N1. Published weighted mean 40Ar/39Ar ages on volcanic ash layers in this part of the section with height from the base and ages in parentheses are: Tuff A (34 m; 3.60 ± 0.02 Ma), Tuff B-α (65 m; 3.43 ± 0.01 Ma), Tuff B-δ (77 m; 3.41 ± 0.01 Ma), Tuff in B-10-1 (150 m; 2.97 ± 0.01 Ma), Tuff C (170 m; 2.99 ± 0.09 Ma), Tuff D (252 m; 2.53 ± 0.01 Ma), Tuff D-3-2 (272 m; 2.47 ± 0.01 Ma), and Tuff F (228 m; 2.32 ± 0.01 Ma). These direct age results imply that the identified polarity zones correspond to the Gilbert Chron, lower Gauss Chron, Mammoth Subchron, upper Gauss Chron, and lower Matuyama Chron, respectively. No new paleomagnetic data are available for the Usno Formation, but tephrostratigraphic work results in reinterpretation of the stratigraphy suggesting that only the Mammoth Subchron is preserved in the upper part of this formation. In the Shungura, Usno and Koobi Fora formations, the thickness represented by the lower Gauss and Mammoth Subchron is very similar, but the Kaena Subchron is either not recorded in the type area of the Shungura Formation, or only incompletely revealed. [ABSTRACT FROM AUTHOR]

In the area of carbonate or karst Dinarides, besides the dominant carbonate rocks and subordinate clastics, in more places more significant mass of chemical sediments can be found, represented by gypsum and anhydrite. As chemical sediments are specifically lighter than overlying rocks, they have been, during the long geological history, trying to achieve isostatic equilibrium, or get out on the ground surface. In recent times, in areas with chemical sediments, a larger tectonic activity is noted than in the wider environment. This is certainly reflected in increased vertical and tangential displacements along major faults in relation to the surrounding area, which are built mainly of carbonate deposits. Determining the amount of movement of diapiric bodies, as absolute and relative, using the most modern surveying methods, precisely would assist the understanding of the tectonic movements and recent structural relations in a wider area [ABSTRACT FROM AUTHOR]

In the development of the hydrographical network from the south of the Iezer Mountains between Valea Mare-Pravăţ and Stoeneşti-Cetăţeni one can distinguish three periods: inferior-Miocene, in which there is visible a wide valley with psefit-peltic accumulations in the surrounding sea basin; medium Miocene - Pliocene with clearly-cut valleys in the mountains, with the presence of some debris from a field close by to the mountains, on which valley chutes have transversely extended; intermittent tectonic movements have been detected in this period, which have triggered both slight elevations and mild dips that have led during the Pliocene towards a sedimentary environment. In the Romanian upper-Pliocene in which the mountain elevations are finally settled down, there are breaks into the non-proclivity crests from the sub-Carpathians, which determine an asymmetrical proclivity-inclined couloir towards the mountain. New generations of torrential valleys come up, which are transversely oriented on the previous ones (springing from the mountains. [ABSTRACT FROM AUTHOR]

Little has been known about the impacts of past vicariance events on the phylogeography and population structure of freshwater fishes in East Asia. The aims of this study are to assess the genetic variability with extensive sampling throughout the range of Chinese spiny loach, Cobitis sinensis, and to infer the genetic structure and evolutionary history of populations. Cobitis sinensis in China may have initiated from two ancestral populations, namely Yangtze and Pearl Rivers, which diverged about 7.24 MYA likely due to drainage systems alteration. In the phylogroup I, a southward dispersal event occurred from East China ( Yangtze River) to south Zhe Min and Hainan subregions, followed by eastward dispersal from Zhe Min to south Taiwan. In the phylogroup II, eastward colonization took place from Pearl River to north Taiwan in the late Pliocene, coupled with loss of genetic diversity in the island populations. This study showed that Cenozoic tectonic movements and climatic and sea-level fluctuations may have shaped the genetic structure of C. sinensis in concert. Highly diverged mt DNA sequences suggest existence of cryptic species in morphospecies C. sinensis. [ABSTRACT FROM AUTHOR]

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Abstract: In 1990 a quartz tube extensometer was installed in the Sopronbánfalva Geodynamic Observatory (SGO) of the Geodetic and Geophysical Research Institute of the Hungarian Academy of Sciences. On the basis of the 20 year data series, an average strain rate of −5.36μstr/y was determined. Because the instrumental drift can also cause a slow change in the output signal of the sensor similar to the tectonic movements, a lot of efforts were made to determine the drift of the extensometer. The instrument has no detectable drift according to the instrumental calibrations (regular calibration, parallel recording by more displacement sensors, etc.). Since autumn of 2008, the radon concentration has been continuously monitored by an AlfaGuard instrument in the SGO. The investigation of the relationship between strain and radon concentration also showed the absence of instrumental drift, so the instrument measures real tectonic movements. The results of the extensometric measurements show that the rate of tectonic movement is not constant. During the period 1993–2001, the strain rate accelerated to a maximum of −8.6μstr/y in 2001, and then decelerated again between 2002 and 2010 to approx. −2.5μstr/y in 2010. [Copyright &y& Elsevier]

Abstract: In the Phanerozoic, the sea depth in epeiric sedimentary basins showed considerable variations, often accompanied by regression. In periods of regression and erosion, the subaerially exposed shelf and the adjacent parts of the marine basins gave rise to numerous nonstructural (stratigraphic) hydrocarbon traps. Sea depth variations with a magnitude of up to 100–200 m and 1–3 myr long (third-order cycles) are usually attributed to the eustatic fluctuations of the sea level. To estimate their possible range, a model is proposed which describes the water depth variations as a function of eustatic fluctuations in tectonically subsiding carbonate platforms. We take into account the crustal isostatic response to the changing water load and the finite time necessary for soil and karst formation in the exposed shelf or its upper part. This model allowed analyzing data on the reference sections of the North Timan shallow-water sediments. According to the analysis, the third-order sea level changes in the Middle Carboniferous, Late Carboniferous, and Early Permian did not exceed several tens of meters. During the same period, shorter fluctuations (∼100 kyr) occurred owing to the waxing and waning of large Gondwanan ice sheets. In the first half of the Bashkirian Age (Early Pennsylvanian), regression took place in the East European and North American cratons and then shallow-water sedimentation resumed. This regression is usually attributed to a considerable sea level fall. In some other areas, slow shallow-water sedimentation continued throughout the Bashkirian. This suggests that the Bashkirian regression was due to the crustal uplifts. Short-term uplifts can be explained by ascending convective currents beneath the asthenosphere. In southern North America, they brought an active fluid into the lithosphere. This caused rapid eclogitization-related crustal subsidence in the Arkoma and Anadarko basins as well as intense lithospheric weakening and shortening in the Ouachita Fold Belt. [Copyright &y& Elsevier]

In order to study the relationship of energy mineral deposits and tectonic movements in Ordos basin, more than 82 samples were taken for determination of apatite and zircon fission tracks. Furthermore, 93 apatite and zircon fission tracks have been selected from other publications. According to these data and other geological background, the evolution of Ordos basin can be divided into 4 stages, and the reformation of the basin can be divided into 5 stages. The basin formation and development were controlled by regional geodynamics. Oil, coal, nature gas and uranium deposits were formed in deferent stages. In the same time, 140 samples were taken and analyzed by organic and inorganic geochemical methods. The results indicate that coal and source rocks generate oil and natural gas, which migrate through reservoir rocks. Oil and natural gas changed the redox conditions of sediments and let uranium accumulate in the sandstones. [ABSTRACT FROM AUTHOR]

Abstract: In Hungary four extensometric observatories were established in the last two decades. The extensometers were installed primarily for observations of Earth tides. A 15-year continuous data series (1991–2005) was recorded at the Sopronbánfalva station and a 7-year record (1993–1999) was obtained at the Pécs station. The length of the measured continuous data series at the two other stations (Bakonya and Budapest) is only a few years. The long-term data records were also applied to the investigation of long-periodic deformations caused by recent tectonic movements. To get an insight into the present day tectonic processes on the margin of the Pannonian Basin, the measurement results of two additional stations (Vyhne in Slovakia and Beregovo in Ukraine) were also included into the investigations. The seasonal variations in the long data series due to temperature and air pressure effects were eliminated. The residual curve – after the correction of the seasonal effects and filtering the “high frequency” components (e.g. earthquakes, Earth tides, etc.) – contains the instrumental drift. It is impossible to determine this curve mathematically. It can be diminished by special instrumental solutions and by regular calibration of the instruments. This paper shows methods and possible solutions how the instrumental drift was investigated and eliminated in order to get the most reliable data for studying recent tectonic movements. The reliability of the extensometric measurements was tested by the tidal evaluation of the data series. The results of the observations show that the Pannonian Basin is under compressive stress. The strain rates measured by extensometers on the margin of the basin are about three orders of magnitude higher than the intra-plate strains obtained by GPS measurements. The reason for this large difference arises from the interaction between the plate boundary and intra-plate forces and from the different measurement techniques. Investigations showed that the rate of the tectonic movements varies, and depends on the local geographical and topographical conditions. [Copyright &y& Elsevier]

Abstract: Geologic studies have illustrated that the planetary-wind-dominant climate in the Paleogene is changed into the monsoon-dominant one near the Oligocene/Miocene boundary in China. The evolution is marked by the changes of regional aridity/humidity contrasts. The contrasts occur between the south and the north part of China in the Eocene, and then between East China and Central Asia near the Oligocene/Miocene boundary, indicating the onset of monsoon-dominant climate in China. The impacts of the Himalaya–Tibetan plateau uplift and/or the Paratethys Sea retreat on the Asian monsoon have been well demonstrated. However, whether or not other factors have affected the above reorganization of paleoclimatic patterns remains a question to be addressed. Additional factors that should be addressed at least include the Indian Peninsular drift, the South China Sea expansion and the East China Sea transgression. Here we use the IAP-AGCM to explore their roles in the above paleoclimatic evolution. Our experiments demonstrate that the South China Sea expansion is another major forcing, in addition to the important roles of the Paratethys retreat and the Himalaya–Tibetan plateau uplift. On the contrary the impacts of the Indian Peninsular drift and the East China Sea transgression are relatively subordinate. The Himalaya–Tibetan plateau uplift plays a crucial role in the magnification of the aridity/humidity contrasts between the south and the north part of China. The Paratethys retreat, the Himalaya–Tibetan plateau uplift and the South China Sea expansion coact to cause the formation of the aridity/humidity contrasts between East China and Central Asia. The retreat and the uplift favor the dynamic condition, and the expansion provides the water vapor condition for the monsoon-dominant climate in China. [Copyright &y& Elsevier]

Abstract: The hybrid actuator–damper–bracing control (HDABC) system is composed of visco-elastic dampers and hydraulic actuators as the passive and active controllers, respectively, which are installed on the brace and connected to the building floor. The intelligent control strategy is designed to maximally utilize the passive damper and to minimally utilize the active energy. Thus, the passive controller of the hybrid system is designed for small and moderate earthquakes and the active controller works for large earthquakes, whenever the structural response exceeds the threshold values. The hybrid control system with this strategy is studied under existing earthquake records and the ground motions generated considering the tectonic movements of seismic plates; the influence of soil–structure interaction (SSI) on the control effectiveness is investigated. Based on analyses of single-story and six-story structures, it is concluded that the intelligent strategy is effective for the hybrid control, and SSI needs to be included in the design of the intelligent hybrid system as well as other types of control for buildings on soft soil. [Copyright &y& Elsevier]

Abstract: Landform analysis of basement rocks has been undertaken with the aid of digital elevation data, aerial photographs and field observations in central West Greenland (69°15′N–66°00′N). Palaeosurfaces have been identified, dated relatively to each other, used to quantify uplift and fault movements and also used to estimate differential erosion. Two types of palaeosurfaces were mapped across the Precambrian basement: a surface at low elevation with distinct hills (hilly relief), and two planation surfaces formed across different types of basement rocks. The hilly relief surface emerges as an inclined surface from Cretaceous cover rocks in Disko Bugt and is interpreted as a stripped late Mesozoic etch surface. This surface is cut off towards the south by a less inclined planation surface, which is younger and thus of Cenozoic age. It is similar to the post-Eocene (Miocene?) planation surfaces identified on Disko and Nuussuaq in other studies. The planation surface splits in two southwards towards high areas around Nordre Isortoq and Sukkertoppen Ice Cap. The upper planation surface forms near-summit areas of tectonic blocks dipping in different directions and with different tilts. The uplift centres define the crests of two mega blocks, separated by the ‘Sisimiut Line’ which coincides with the Precambrian Ikertôq thrust zone. A partially developed lower planation surface indicates a first uplift of maximum 500 m followed by a second uplift of maximum 1000 m. We infer that these uplift events occurred during the late Neogene based on correlation with similar surfaces on Nuussuaq and the timing of exhumational events estimated from apatite fission track analyses of samples from a deep borehole on Nuussuaq (reported elsewhere). The difference between a reconstruction of the upper planation surface across the entire area and the present topography was used as an estimate of erosion of basement rock since the formation of the upper planation surface. The erosion is unevenly distributed and varies from almost none on the well-preserved planation surfaces to 800–1300 m along valleys, and even more in the fjords. Erosion is less within areas of gneiss in granulite facies, than in areas of gneiss in amphibolite facies. [Copyright &y& Elsevier]

Sedimentological, paleontological, and geochemical data from core XK-1 on the Xisha Islands have allowed for a detailed documentation of the early carbonate development around the Oligocene-Miocene transition in the northern South China Sea (SCS). The deposits within the fore reef, reef, lagoon environments occurred before 23 Ma, the exposure horizon occurred around 23 Ma, and the sediments within the open lagoon setting dominated after 23 Ma. This evolution indicates a sedimentological response to water depth change, which is the combined result of eustatic sea-level fluctuations and tectonic subsidence. The tectonic subsidence during the latest Oligocene and Early Miocene (especially this period) was responsible for the obvious deepening trend. What's more, substantial physical erosion caused an increased amount of terrigenous input into the Xisha Islands area, with detrimental effects on carbonate development after the Oligocene-Miocene boundary. Over the entire South China Sea, the early carbonate systems along the northern and southern margins displayed specific evolution patterns. After comparing these patterns, we found a close relationship between the carbonate initiation and the subduction of the proto-SCS and the opening of the modern SCS. Therefore, it has been demonstrated that sea level and local tectonics as well as paleoclimatic conditions were the main controlling factors in shaping the onset of carbonate sedimentation in the SCS. • Plentiful corals existed during Oligocene in both northern and southern parts of SCS. • Strong physical erosion favored dominance of algae and foraminifera over corals. • Early growth of carbonates is linked to proto-SCS subduction and new-SCS opening. [ABSTRACT FROM AUTHOR]