Geološki anali Balkanskoga poluostrva

Bi-directional extensional control of the Berane Basin formation, northern Montenegro

2024-12-24T12:28:07+00:00

The Berane Basin is a Miocene, northeast-southwest oriented intramountain basin of the Dinarides, overlying the pre-neotectonic basement of the Drina-Ivanjica unit, the East Bosnian-Durmitor unit and the Western Vardar Zone. The structural evolution and the tectonic regimes that controlled the formation of the Berane Basin are not fully understood. In this paper, we conducted field kinematic analysis by applying fault-slip inversion to derive paleostress regimes and study the deformation phases that led to the formation of the Berane Basin. Observed deformation is related to the Miocene extension in two directions, perpendicular and parallel to the Dinarides orogen. Such bi-directional extension resulted in a complex fault pattern where, among observed normal, oblique and strike-slip faults, those with oblique-normal slip dominate. The observed faults likely form a system of mutually overprinting half-grabens, mainly driven by orogen-parallel extension associated with the large-scale regional Skadar-Peć Fault, while orogen-perpendicular extension has subordinate effects on the Berane Basin formation.

Middle to Late Jurassic pelagites and gravity mass flow deposits of a displaced Neotethyan margin

2024-12-24T12:28:08+00:00

Microfacies, depositional age and sedimentary environment were characterised for two Jurassic successions, which were deposited on the Adriatic microcontinental margin of the Neotethys Ocean. Investigations were carried out mostly on cores drilled in the Mesozoic basement of the eastern part of the Matra Mountains (Recsk area) and the westernmost part of the Bukk Mountains, NE Hungary. This area represents the continuation of the Inner Dinaric nappe-system, and was displaced along the Mid-Hungarian Shear Zone during the Late Oligocene to Early Miocene. The pre-Cenozoic basement of the area is characterised by three juxtaposed units: the lowermost Recsk Succession, the Tarna Olistostrome and the topmost Darnohegy Melange nappe. The Recsk Succession is made up of Upper Triassic, cherty carbonates of pelagic basin facies that are overlain by pelagic limestones of Early to early Middle Jurassic age. The carbonate sedimentation changed gradually into shale-dominated one during the late Bathonian to the early Callovian. In the Bajocian to early Callovian interval the Recsk area was located at the toe of a coeval carbonate platform, which provided gravitational mass flows reaching the investigated area. The external margin of this platform drowned and got covered by the pelagic shale in the late Bajocian. The Tarna Olistostrome is built up by a Tithonian pelagic mixed carbonatic and siliciclastic succession with breccia/ olistostrome horizons. The clasts derived from the Upper Permian-Lower Jurassic succession of a distal Adriatic margin. The Darnohegy Melange is a typical sub-ophiolitic melange comprising scrapped off blocks and slices from the lower plate and gravitationally redeposited / tectonically sheared blocks from the overriding ophiolite nappe. The age of the melange is Callovian-Oxfordian. These inferences may serve as a base for new geodynamic evaluations of the studied region.

Geological Structure Identification inGeothermal Manifestation of LamonganVolcano Complex: A Magnetic DataAnalysis Approach

2024-12-24T12:37:17+00:00

Tiris area in Lamongan Volcano Complex, Probolinggo, East Java, is estimated to be an area with geothermal potential in Indonesia. There are several hot springs along the Tancak River that form a continuous line with a distance of about 20–50 meters between hot springs. One of the hydrothermal manifestations that can indicate the existence of geothermal potential in this location is the Segaran Hot Springs. The identification of geothermal manifestations in this location is limited, so it still needs to be developed using magnetic methods to identify subsurface geological structures. Some previous research has shown the existence of subsurface geological structures around Segaran hot springs in a northwest-southeast direction. Magnetic data collection was taken by following the contours of the research area, so the interval between data points varied greatly, with a total of 117 data points. First Horizontal Derivative (FHD) and Second Vertical Derivative (SVD) analyses were carried out to delineate the boundaries of the magnetic anomaly. To determine the depth of the magnetic anomaly, Euler Deconvolution analysis was performed and overlaid with derivative analysis. The integration of the three analyses on the magnetic data is sufficient to interpret the presence and direction of subsurface structures in the research area. The result shows the presence of lineaments in the Lamongan Volcano Complex through Segaran hot springs with a northwest-southeast orientation. This result corresponds with the dominant orientation from the density lineaments analysis performed based on DEMNAS. The existence of geological structures associated with Segaran hot springs can enhance the indication of geothermal potential in Lamongan Volcano Complex, especially in Tiris area.

Landslide susceptibility assessment by implementing the analytical hierarchy process in GIS weight overlay tool: A case study of the Krupanj area in Western Serbia

2024-12-24T12:28:09+00:00

The aim of this work is to show the susceptibility to sliding in the Krupanj area. Intense rainfall in May 2014 triggered many landslides in western Serbia. The Krupanj area was particularly affected by this event. The material damage occurred affected the awareness of the importance of knowing the locations that are prone to sliding. Therefore, from 2014 to 2021, field research was carried out in the Krupanj area. During this period a large amount of landslide data was collected by engineering geological mapping. These data were used for susceptibility analysis. For present study was used analytical hierarchy process (AHP) and weighted overlay (WO) method. Nine factors were used for susceptibility analysis: slope, aspect, curvature, elevation, lithology, distance from rivers, faults, boundary’s and land cover. In order to be able to compare all factors were first standardized and then evaluated using Saaty scale. The weights of each factor were obtained. The weight values obtained by AHP were used for WO model. Both map was validated by ROC graph. The validation results show 68.6% (satisfactory) and 77.2% (good) for AHP and WO models. We can conclude that AHP map is more detailed but less reliable compared to WO map.

Zoning of infiltration areas using Schosinsky’s Soil Water Balance in La Balsa River Basin, Costa Rica

2024-12-24T12:28:51+00:00

In Central America there is little information of water infiltration at the basin level, despite its importance for the design of appropriate conservation and restoration strategies. Thus, the aim of this study is to develop an example for how to use Schosinsky’s Soil Water Balance (SSWB) model-along with other variables-as a more viable way to determine water infiltration zones at the basin level. Zones, in La Balsa River Basin (LBRB), were determined by overlaying information of basin slopes, existing land use, land cover and spatial distributed rainfall. Hydrophysical soil properties in each zone were obtained through field tests measurements and laboratory analyses of soil samples. Once the values of each zone were determined, SSWB model was applied to obtain a map of infiltration zones. Results indicate that rainfall is the most influential component in calculating SSWB, and its distribution and deposition on the ground as effective rainfall is related to soil exposure and land use characteristics. Soil properties control the behavior of water that enters the soil and replenishes groundwater. Infiltration values, obtained using the model are highly correlated to rainfall dynamics. It is concluded that SSWB model is an important tool for obtaining water infiltration estimates at the basin level, useful in those basins for which little information is available.

Geodynamics of basins above subducted slabs: An integrated modelling study of tectonics, sedimentation, and magmatism in the Timok Magmatic Complex

2024-12-24T12:28:07+00:00

Volcano-sedimentary basins located in the orogenic hinterland area overlying subducted slabs are observed worldwide to be driven by the switching tectonic regimes induced by the changing mechanics of the slab. Despite many qualitative studies, the quantitative link between the subducted slab’s mechanics and the overlying basins’ evolution is less understood. Among the many examples observed worldwide, the Timok Magmatic Complex (TMC) in Serbia represents an optimal natural laboratory due to the complex tectonic setting during the various stages of the Middle Jurassic-Paleogene evolution of the subduction system. The TMC is a segment of the larger Late Cretaceous Apuseni-Banat-Timok-Srednogorie (ABTS) magmatic belt, formed in response to the evolution of the subducted Mesozoic Neotethys oceanic slab beneath the Carpatho-Balkanides of south-eastern Europe. The TMC basin, with the associated intrusive and extrusive magmatics and volcano-sedimentary deposits, represents an excellent area for a process-oriented study on the interplay between tectonics, sedimentation, and magmatism in the basins above evolving subducted slabs. Within the scope of the newly funded TMCmod project, coupled field and laboratory kinematic and petrological investigations will be focused on creating a conceptual definition of the TMC geodynamic evolution, by combining near-surface observations with the known evolution of the subduction system. This definition will be subsequently validated through analogue modelling and integrated into a coherent geodynamic model of tectonic switching in basins driven by the evolution of subducted slabs. The new model of the TMC basin’s geodynamic evolution will quantitatively advance the strategy of prospecting and exploration of world-class porphyry copper- gold deposits, which have been actively exploited in this region for more than a century. Furthermore, reconstructed regional kinematic evolution will improve seismic hazard assessment during industrial and societal infrastructure planning and construction.