Geosciences

31 pages, 83141 KiB

Open AccessArticle

The Relationships between the Internal Nappe Zone and the Regional Mylonitic Complex in the NE Variscan Sardinia (Italy): Insight from a New Possible Regional Interpretation?

by Franco Marco Elter and Federico Mantovani

Geosciences 2024, 14(10), 260; https://doi.org/10.3390/geosciences14100260 - 28 Sep 2024

Abstract

This study presents an updated interpretation of geological data collected between 1984 and 2022. The area under consideration holds significant regional importance as it is located between the Internal Nappe Zone (INZ) and the Regional Mylonitic Complex (RMC). Re-evaluation of the geological data [...] Read more.

This study presents an updated interpretation of geological data collected between 1984 and 2022. The area under consideration holds significant regional importance as it is located between the Internal Nappe Zone (INZ) and the Regional Mylonitic Complex (RMC). Re-evaluation of the geological data has highlighted a more intricate structural framework than what is currently documented in the existing literature. This paper aims to illustrate, through structural analysis, that the Posada Valley Shear Zone (PVSZ) does not serve as the transitional boundary between the Inner Nappe Zone and the Regional Mylonitic Complex or High-Grade Metamorphic Complex (HGMC) as traditionally thought. Instead, the authors’ findings indicate that the transition boundary is confined to a shear band with a variable thickness ranging from 10 to 70 m at its widest points. The development of the Posada Valley Shear Zone is characterized by a series of transitions from mylonite I S-C to mylonite II S-C, extending over approximately 5 km. The formation of the Posada Valley Shear Zone is chronologically confined between the development of the East Variscan Shear Zone (EVSZ) and the emplacement of the Late Variscan granites. The differing orientations of Sm and S3 observed in the mylonitic events of the Posada Valley Shear Zone and the Regional Mylonitic Complex, respectively, are likely attributable to an anticlockwise rotation of the shortening directions during the upper Carboniferous period. Furthermore, this study proposes that the Condensed Isogrades Zone (CIZ), despite its unclear formation mechanism, should be recognized as the true transition zone between the Inner Nappe Zone and the Regional Mylonitic Complex or High-Grade Metamorphic Complex. This new interpretation challenges the previously accepted notion of increasing Variscan metamorphic zonation toward the northeast. This conclusion is supported by the identification of the same NE–SW orientation of the D2 tectonic event in both the Old Gneiss Complex (OGC in the Regional Mylonitic Complex) and the lithologies of the Inner Nappe Zone and the Condensed Isogrades Zone. The comprehensive analysis and new insights provided in this paper contribute to a refined understanding of the geological relationships and processes within this region, offering significant implications for future geological studies and interpretations. Full article

(This article belongs to the Special Issue Metamorphism and Tectonic Evolution of Metamorphic Belts)

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23 pages, 7079 KiB

Open AccessArticle

Multitemporal Quantification of the Geomorphodynamics on a Slope within the Cratére Dolomieu—At the Piton de la Fournaise (La Réunion, Indian Ocean) Using Terrestrial LiDAR Data, Terrestrial Photographs, and Webcam Data

by Kerstin Wegner, Virginie Durand, Nicolas Villeneuve, Anne Mangeney, Philippe Kowalski, Aline Peltier, Manuel Stark, Michael Becht and Florian Haas

Geosciences 2024, 14(10), 259; https://doi.org/10.3390/geosciences14100259 - 28 Sep 2024

Abstract

In this study, the geomorphological evolution of an inner flank of the Dolomieu at Piton de La Fournaise/La Réunion was investigated with the help of terrestrial laser scanning (TLS) data, terrestrial photogrammetric images, and historical webcam photographs. While TLS data and the terrestrial [...] Read more.

In this study, the geomorphological evolution of an inner flank of the Dolomieu at Piton de La Fournaise/La Réunion was investigated with the help of terrestrial laser scanning (TLS) data, terrestrial photogrammetric images, and historical webcam photographs. While TLS data and the terrestrial images were recorded during three field surveys, the study was also able to use historical webcam images that were installed for the monitoring of the volcanic activity inside the crater. Although the webcams were originally intended to be used only for visual monitoring of the area, at certain times they captured image pairs that could be analyzed using structure from motion (SfM) and subsequently processed to create digital terrain models (DTMs). With the help of all the data, the geomorphological evolution of selected areas of the crater was investigated in high temporal and spatial resolution. Surface changes were detected and quantified on scree slopes in the upper area of the crater as well as on scree slopes at the transition from the slope to the crater floor. In addition to their quantification, these changes could be assigned to individual geomorphological processes over time. The webcam photographs were a very important additional source of information here, as they allowed the observation period to be extended further into the past. Besides this, the webcam images made it possible to determine the exact dates at which geomorphological processes were active. Full article

(This article belongs to the Section Natural Hazards)

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27 pages, 39557 KiB

Open AccessArticle

Application of Experimental Configurations of Seismic and Electric Tomographic Techniques to the Investigation of Complex Geological Structures

by Vasileios Gkosios, John D. Alexopoulos, Konstantinos Soukis, Ioannis-Konstantinos Giannopoulos, Spyridon Dilalos, Dimitrios Michelioudakis, Nicholas Voulgaris and Thomas Sphicopoulos

Geosciences 2024, 14(10), 258; https://doi.org/10.3390/geosciences14100258 - 28 Sep 2024

Abstract

The main purpose of this study is the subsurface investigation of two complex geological environments focusing on the improvement of data acquisition and processing parameters regarding electric and seismic tomographic techniques. Two different study areas, in central–east Peloponnese and SE Attica, were selected, [...] Read more.

The main purpose of this study is the subsurface investigation of two complex geological environments focusing on the improvement of data acquisition and processing parameters regarding electric and seismic tomographic techniques. Two different study areas, in central–east Peloponnese and SE Attica, were selected, where detailed geological mapping and surface geophysical survey were carried out. The applied geophysical survey included the application of electrical resistivity tomography (ERT), seismic refraction tomography (SRT) and ground penetrating radar (GPR). The geoelectrical measurements were acquired with different arrays and electrode configurations. Moreover, various types of seismic sources were used at seventeen shot locations along the seismic arrays. For the processing of geoelectrical data, clustered datasets were created, increasing the depth of investigation and discriminatory capability. The seismic data processing included the following: (a) the creation of synthetic models and seismic records to determine the effectiveness and capabilities of the technique, (b) spectral analysis of the seismic records to determine the optimal seismic source type and (c) inversion of the field data to create representative subsurface velocity models. The results of the two techniques successfully delineated the complex subsurface structure that characterizes these two geological environments. The application of the ERT combined with the SRT are the two dominant, high-resolution techniques for the elucidation of complex subsurface structures. Full article

(This article belongs to the Section Geophysics)

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16 pages, 54958 KiB

Open AccessArticle

Seismotectonic Setting of the Andes along the Nazca Ridge Subduction Transect: New Insights from Thermal and Finite Element Modelling

by Sara Ciattoni, Stefano Mazzoli, Antonella Megna and Stefano Santini

Geosciences 2024, 14(10), 257; https://doi.org/10.3390/geosciences14100257 - 28 Sep 2024

Abstract

The structural evolution of Andean-type orogens is strongly influenced by the geometry of the subducting slab. This study focuses on the flat-slab subduction of the Nazca Ridge and its effects on the South American Plate. The process of flat slab subduction impacts the [...] Read more.

The structural evolution of Andean-type orogens is strongly influenced by the geometry of the subducting slab. This study focuses on the flat-slab subduction of the Nazca Ridge and its effects on the South American Plate. The process of flat slab subduction impacts the stress distribution within the overriding plate and increases plate coupling and seismic energy release. Using the finite element method (FEM), we analyse interseismic and coseismic deformation along a 1000 km transect parallel to the ridge. We examine stress distribution, uplift patterns, and the impact of megathrust activity on deformation. To better define the crust’s properties for the model, we developed a new thermal model of the Nazca Ridge subduction zone, reconstructing the thermal structure of the overriding plate. The results show concentrated stress at the upper part of the locked plate interface, extending into the Coastal and Western Cordilleras, with deeper stress zones correlating with seismicity. Uplift patterns align with long-term rates of 0.7–1 mm/yr. Cooling from flat-slab subduction strengthens the overriding plate, allowing far-field stress transmission and deformation. These findings provide insights into the tectonic processes driving stress accumulation, seismicity, and uplift along the Peruvian margin. Full article

(This article belongs to the Special Issue New Trends in Earthquake Engineering and Seismotectonics)

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34 pages, 40857 KiB

Open AccessArticle

Application of the Coastal Marine Ecosystem Classification System (CMECS) to Create Benthic Geologic Habitat Maps for Portions of Acadia National Park, Maine, USA

by Bryan Oakley, Brian Caccioppoli, Monique LaFrance Bartley, Catherine Johnson, Alexandra Moen, Cameron Soulagnet, Genevieve Rondeau, Connor Rego and John King

Geosciences 2024, 14(10), 256; https://doi.org/10.3390/geosciences14100256 - 28 Sep 2024

Abstract

The Coastal and Marine Ecological Classification Standard (CMECS) was applied to four portions of Acadia National Park, USA, focusing on intertidal rocky and tidal flat habitats. Side-scan sonar coupled with multi-phase echo sounder bathymetry are the primary data sources used to map the [...] Read more.

The Coastal and Marine Ecological Classification Standard (CMECS) was applied to four portions of Acadia National Park, USA, focusing on intertidal rocky and tidal flat habitats. Side-scan sonar coupled with multi-phase echo sounder bathymetry are the primary data sources used to map the seafloor, coupled with underwater video imagery and surface grab samples for grain size and macrofaunal analysis. The CMECS Substrate, Geoform, and Biotic components were effective in describing the study areas. However, integrating the CMECS components to define Biotopes was more challenging due to the limited number of grab samples available and because the dominant species within a given map unit is largely inconsistent. While Biotopes ultimately could not be defined in this study, working within the CMECS framework to create statistically significant biotopes revealed the complexity of these study areas that may otherwise have been overlooked. This study demonstrates the effectiveness of the CMECS classification, including the framework’s ability to be flexible in communicating information. Full article

(This article belongs to the Special Issue Progress in Seafloor Mapping)

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16 pages, 757 KiB

Open AccessReview

Deterministic Physically Based Distributed Models for Rainfall-Induced Shallow Landslides

by Giada Sannino, Massimiliano Bordoni, Marco Bittelli, Claudia Meisina, Fausto Tomei and Roberto Valentino

Geosciences 2024, 14(10), 255; https://doi.org/10.3390/geosciences14100255 - 27 Sep 2024

Abstract

Facing global warming’s consequences is a major issue in the present times. Regarding the climate, projections say that heavy rainfalls are going to increase with high probability together with temperature rise; thus, the hazard related to rainfall-induced shallow landslides will likely increase in [...] Read more.

Facing global warming’s consequences is a major issue in the present times. Regarding the climate, projections say that heavy rainfalls are going to increase with high probability together with temperature rise; thus, the hazard related to rainfall-induced shallow landslides will likely increase in density over susceptible territories. Different modeling approaches exist, and many of them are forced to make simplifications in order to reproduce landslide occurrences over space and time. Process-based models can help in quantifying the consequences of heavy rainfall in terms of slope instability at a territory scale. In this study, a narrative review of physically based deterministic distributed models (PBDDMs) is presented. Models were selected based on the adoption of the infinite slope scheme (ISS), the use of a deterministic approach (i.e., input and output are treated as absolute values), and the inclusion of new approaches in modeling slope stability through the ISS. The models are presented in chronological order with the aim of drawing a timeline of the evolution of PBDDMs and providing researchers and practitioners with basic knowledge of what scholars have proposed so far. The results indicate that including vegetation’s effects on slope stability has raised in importance over time but that there is still a need to find an efficient way to include them. In recent years, the literature production seems to be more focused on probabilistic approaches. Full article

(This article belongs to the Section Natural Hazards)

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15 pages, 5438 KiB

Open AccessArticle

The Relationships between Greenstone Belts and the Kryvyi Rih–Kremenchuk Basin in the Middle Dnieper Domain of the Ukrainian Shield Revealed by Detrital Zircon

by Hennadii Artemenko, Leonid Shumlyanskyy, David Chew, Foteini Drakou, Bruno Dhuime, Hugo Moreira and Valeryi Butyrin

Geosciences 2024, 14(10), 254; https://doi.org/10.3390/geosciences14100254 - 27 Sep 2024

Abstract

Detrital zircons from two samples of metasandstones from the Lykhmanivka Syncline, Middle Dnieper Domain of the Ukrainian Shield (Skelevate Formation of the Kryvyi Rih Group), have been dated by the LA-ICP-MS U-Pb method. Metasandstones from the northern part of the syncline yield zircons [...] Read more.

Detrital zircons from two samples of metasandstones from the Lykhmanivka Syncline, Middle Dnieper Domain of the Ukrainian Shield (Skelevate Formation of the Kryvyi Rih Group), have been dated by the LA-ICP-MS U-Pb method. Metasandstones from the northern part of the syncline yield zircons belonging to four age groups: 3201 ± 12 Ma, 3089 ± 11 Ma, 2939 ± 8 Ma, and 2059 ± 4 Ma. All three Archean groups originated from similar rock types that crystallized at different times from the same mafic source (lower crust) with a ¹⁷⁶Lu/¹⁷⁷Hf ratio of about 0.020. In contrast, zircon from metasediments from the southern end of the Lykhmanivka Syncline fall within two age groups: 3174 ± 13 Ma, and 2038 ± 9 Ma. In terms of Hf isotope compositions, the detrital zircons from the two oldest age groups in both samples are very similar. The source area was dominated by rocks of the Auly Group (3.27–3.18 Ga) and the Sura Complex (3.17–2.94 Ga). The proportion of zircons dated at 2.07–2.03 Ga, which reflects the timing of metamorphism, is 5%. The metamorphic nature of the Paleoproterozoic zircon allows us to define the maximum depositional age of the metasandstones of the Lykhmanivka Syncline at ca. 2.9 Ga, which is in good agreement with the earlier results from the metaterrigenous rocks of the Kryvyi Rih–Kremenchuk Basin. Our data also indicate the local nature of sedimentation and the absence of significant transport and mixing of detrital material within the basin. Full article

(This article belongs to the Section Geochemistry)

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25 pages, 3229 KiB

Open AccessReview

Evaluation of Strength Anisotropy in Foliated Metamorphic Rocks: A Review Focused on Microscopic Mechanisms

by Umer Waqas, Mohsin Usman Qureshi, Shahab Saqib, Hafiz Muhammad Awais Rashid and Ali Murtaza Rasool

Geosciences 2024, 14(10), 253; https://doi.org/10.3390/geosciences14100253 - 26 Sep 2024

Abstract

This review paper addresses the recent and past advancements in investigating the anisotropic behavior of foliated metamorphic rock strength subjected to uniaxial or triaxial compression loading, direct or indirect tensile loading, and shear loading. The experimental findings published in the literature show that [...] Read more.

This review paper addresses the recent and past advancements in investigating the anisotropic behavior of foliated metamorphic rock strength subjected to uniaxial or triaxial compression loading, direct or indirect tensile loading, and shear loading. The experimental findings published in the literature show that the strength of foliated rocks is significantly affected by varying the angle β between weak planes and major principal stress. A higher value of strength is reported at β = 0° or 90°; whereas a low strength value is noted at intermediate angles between β = 0° and 90°. The strength anisotropy depends on the degree of schistosity or gneissosity, which is the result of the preferred arrangement of phyllosilicate minerals under differential pressures. The failure of foliated rocks starts at the microscopic scale because of the dislocation slip, plastic kinking, and fracturing in phyllosilicate minerals such as mica. Tensile wing cracks at the tip of the mica propagate parallel to the deviatoric stress. Then, intergranular and intragranular shear-tensile cracks coalesce and lead to rock failure. The weak planes’ orientation controls the mode of failure such that tensile splitting, slip failure, and shear failure across foliations are observed at β = 0°–30°, β = 30°–60°, β = 60°–90° respectively. In the past, several attempts have been made to formulate failure criteria to estimate rock strength using different mathematical and empirical approaches. Over the years, the trend has shifted towards discontinuum modeling to simulate rock failure processes and to solve problems from laboratory to upscaled levels. Full article

(This article belongs to the Section Geomechanics)

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23 pages, 103238 KiB

Open AccessArticle

Miocene Petit-Spot Basanitic Volcanoes on Cretaceous Alba Guyot (Magellan Seamount Trail, Pacific Ocean)

by Igor S. Peretyazhko, Elena A. Savina and Irina A. Pulyaeva

Geosciences 2024, 14(10), 252; https://doi.org/10.3390/geosciences14100252 - 25 Sep 2024

Abstract

New data obtained from core samples of two boreholes and dredged samples in the Alba Guyot in the Magellan Seamount Trail (MST), Western Pacific, including the ⁴⁰Ar/³⁹Ar age of basanite, mineralogy of basanite, tuff, tuffite, mantle-derived inclusions in basanite and [...] Read more.

New data obtained from core samples of two boreholes and dredged samples in the Alba Guyot in the Magellan Seamount Trail (MST), Western Pacific, including the ⁴⁰Ar/³⁹Ar age of basanite, mineralogy of basanite, tuff, tuffite, mantle-derived inclusions in basanite and tuff (lherzolite xenolith and Ol, Cpx, and Opx xenocrysts), and calcareous nannofossil biostratigraphy, have implications for the guyot′s history. Volcanics in the upper part of the Alba Guyot main edifice and its Oma Vlinder satellite, at sea depths between 3600 and 2200 m, were deposited during the Cretaceous 112 to 86 Ma interval. In the following ~60 myr, the Alba Guyot became partly submerged and denuded with the formation of a flat summit platform while the respective fragment of the Pacific Plate was moving to the Northern Hemisphere. Volcanic activity in the northeastern part of the guyot summit platform was rejuvenated in the Miocene (24–15 Ma) and produced onshore basanitic volcanoes and layers of tuff in subaerial and tuffite in shallow-water near-shore conditions. In the Middle-Late Miocene (10–6 Ma), after the guyot had submerged, carbonates containing calcareous nannofossils were deposited on the porous surfaces of tuff and tuffite. Precipitation of the Fe-Mn crust (Unit III) recommenced during the Pliocene-Pleistocene (<1.8 Ma) when the guyot summit reached favorable sea depths. The location of the MST guyots in the northwestern segment of the Pacific Plate near the Mariana Trench, along with the Miocene age and alkali-basaltic signatures of basanite, provide first evidence for petit-spot volcanism on the Alba Guyot. This inference agrees with the geochemistry of Cenozoic petit-spot basaltic rocks from the Pacific and Miocene basanite on the Alba Guyot. Petit-spot volcanics presumably originated from alkali-basaltic melts produced by decompression partial melting of carbonatized peridotite in the metasomatized oceanic lithosphere at the Lithosphere–Asthenosphere Boundary level. The numerous volcanic cones reaching up to 750 m high and 5.1 km in base diameter, which were discovered on the Alba summit platform, provide the first evidence of voluminous Miocene petit-spot basanitic volcanism upon the Cretaceous guyots and seamounts of the Pacific. Full article

(This article belongs to the Section Geochemistry)

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12 pages, 2536 KiB

Open AccessArticle

Uncovering Interdecadal Pacific Oscillation’s Dominance in Shaping Low-Frequency Sea Level Variability in the South China Sea

by Bijoy Thompson, Pavel Tkalich, Daiane G. Faller and Johnson Zachariah

Geosciences 2024, 14(10), 251; https://doi.org/10.3390/geosciences14100251 - 25 Sep 2024

Abstract

The low-frequency sea level variability in the South China Sea (SCS) is examined using high-resolution regional ocean model simulations that span the last six decades. The analysis reveals interdecadal oscillations with a periodicity of 12–13 years as the dominant mode of sea level [...] Read more.

The low-frequency sea level variability in the South China Sea (SCS) is examined using high-resolution regional ocean model simulations that span the last six decades. The analysis reveals interdecadal oscillations with a periodicity of 12–13 years as the dominant mode of sea level variability in the SCS. The fluctuations in the Luzon Strait transport (LST) are identified as primary drivers of interannual to interdecadal sea level variability, rather than atmospheric forcing within the SCS. Fourier spectrum analysis is employed to investigate the association between SCS sea level variability and the Interdecadal Pacific Oscillation (IPO), using principal components of SCS sea surface height anomalies, wind stress curl, wind stress components, net short wave flux, as well as the LST and various climate indices. The variations in the SCS sea level are driven by the IPO, which modifies the LST and ocean heat content, impacting the steric sea level. Full article

(This article belongs to the Section Climate)

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21 pages, 4370 KiB

Open AccessArticle

Real-Time Lithology Prediction at the Bit Using Machine Learning

by Tunc Burak, Ashutosh Sharma, Espen Hoel, Tron Golder Kristiansen, Morten Welmer and Runar Nygaard

Geosciences 2024, 14(10), 250; https://doi.org/10.3390/geosciences14100250 - 25 Sep 2024

Abstract

Real-time drilling analysis requires knowledge of lithology at the drill bit. However, logging-while-drilling (LWD) sensors in the bottom hole assembly (BHA) are usually positioned 2–50 m (7–164 ft) above the bit (called the sensor offset), leading to a delay in real-time drilling analysis. [...] Read more.

Real-time drilling analysis requires knowledge of lithology at the drill bit. However, logging-while-drilling (LWD) sensors in the bottom hole assembly (BHA) are usually positioned 2–50 m (7–164 ft) above the bit (called the sensor offset), leading to a delay in real-time drilling analysis. The current industry solution to overcome this delay involves stopping drilling to perform a bottoms-up circulation for cuttings evaluation—a process that is both time-consuming and costly. To address this issue, our study evaluates three methodologies for real-time lithology prediction at the bit using drilling and petrophysical parameters. The first method employs a petrophysical approach, which involves using bulk density and neutron porosity predicted at the bit. The second method combines unsupervised and supervised machine learning (ML) for prediction. The third method employs classification algorithms on manually labeled lithology data from mud log reports, a novel approach used in this work. Our results show varying degrees of success: the bulk density versus neutron porosity cross-plot method achieved an accuracy of 58% with blind-well test data; the ML approach improved accuracy to 66%; and the Random Forest (RF) classification with manual labeling significantly increased accuracy to 86%. This comparative analysis of three different methodologies for lithology prediction has not been previously explored in the literature. While clustering and classification methods have been regarded as the most effective, our study demonstrates that they do not always yield the best result. These findings demonstrate that ML models, particularly the manual labeling approach, substantially outperform the petrophysical method. This new algorithm, designed for real-time applications, uses selected input parameters to effectively minimize problems associated with the sensor offset of LWD tools. It rapidly adapts to changes, offering a quicker and more cost-effective interpretation of lithology. This eliminates the need for time-consuming bottoms-up circulation to evaluate cuttings. Ultimately, this approach enhances drilling efficiency and significantly improves the accuracy of lithology prediction, notably in identifying interbedded geological layers. Full article

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18 pages, 19382 KiB

Open AccessArticle

Geosites of Northern Mountainous Adygeya (Southwestern Russia): A Novel Vision

by Anna V. Mikhailenko and Dmitry A. Ruban

Geosciences 2024, 14(10), 249; https://doi.org/10.3390/geosciences14100249 - 24 Sep 2024

Abstract

Territorial inventories of geosites remain on the international agenda, and they can help in acquiring information for solving pure geological research tasks. New field investigations in the northern part of Mountainous Adygeya (geoheritage-rich territory in the western Greater Caucasus) permitted us to extend [...] Read more.

Territorial inventories of geosites remain on the international agenda, and they can help in acquiring information for solving pure geological research tasks. New field investigations in the northern part of Mountainous Adygeya (geoheritage-rich territory in the western Greater Caucasus) permitted us to extend our knowledge of its geosites. Five geosites were described qualitatively and assessed semi-quantitatively, namely the Polkovnitskaya River Valley (ammonite-bearing concretions of Aptian glauconitic sandstones), the Little Khadzhokh River Valley (Aptian glauconitic sandstones with fossils and trace fossils), the Shakhan and Middle Khadzhokh River Valley (Upper Jurassic variegated siliciclastics, Hauterivian fluvial and deltaic sandstones, mixed ancient and modern clastic material), the Big Khadzhoh Waterfall (splendid waterfall and exposures of locally folded Oxfordian–Kimmeridgian limestones), and the Verblyud Mountain (small, camel-shaped cuesta’s remnant). They were ranked nationally (one geosite), regionally (three geosites), and locally (one geosite). Close examination of the considered geosites permitted to register pure geological peculiarities (changes in the dip direction between sedimentary packages), which indicate the tectonic activity across the Jurassic–Cretaceous transition. Additionally, complex accessibility patterns were established in some geosites, and these patterns should be addressed in further refinements of the semi-quantitative approaches to geosite assessment. Full article

(This article belongs to the Section Geoheritage, Geoparks and Geotourism)

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Geosciences, Volume 14, Issue 10 (October 2024) – 12 articles

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