Geological Diversity Research Articles

Untapped Mineral Potential of Somaliland: A review

This comprehensive study explores the untapped mineral potential of Somaliland, a region rich in geological diversity and significant mineral deposits. By examining the intricate geology of Somaliland, including its ancient Precambrian basement and younger sedimentary sequences, the research uncovers valuable insights into the region's mineral wealth. Extensive exploration activities reveal substantial reserves of base metals, precious metals, industrial minerals, and gemstones, highlighting the region's promise for future mining endeavors. The findings underscore the strategic importance of Somaliland's mineral resources, offering a roadmap for sustainable development and economic growth through enhanced geological surveys, infrastructure investment, and robust regulatory frameworks. This article serves as a vital resource for geologists, investors, and policymakers interested in unlocking the mineral wealth of Somaliland and fostering regional development.

Oral and poster contributions for conferences: Some observations and recommendations

The recent 13th South American Symposium on Isotope Geology (SSAGI) in May 2024 in Buzios (Brazil) was an excellent conference, showcasing the current diversity and high standard of isotope geochemistry and geology at universities and research institutions across Latin America. Three days of oral and poster presentations provided a great forum for scientific and social exchange. This conference, however, also further supported observations made at earlier events that many oral and poster presentations by postgraduate students and docents alike suffer from a number of problems. There is ample scope for improvement, in the interest of more efficient information transfer and better exchange with colleagues. The main problem areas noted (e.g., overloading of powerpoint slides, and of posters, with diagrams and/or text; application of poor color, etc.) are discussed here, and suggestions are made how to avoid these issues and improve our scientific communication.

Geological and Structural Framework, Inventory, and Quantitative Assessment of Geodiversity: The Case Study of the Lake Faro and Lake Ganzirri Global Geosites (Italy)

The geoconservation policies assumed by the Sicilian Region (Italy) induced to classify as geosites all the geodiversity preserved in the Sicilian natural reserves. In particular, two of these geosites present in the oriented natural reserve of the coastal lagoon of Cape Peloro (Messina, NE Sicily, Italy), denoted “Morpho–tectonic system of Cape Peloro–Lake Faro” and “Morpho–tectonic system of Cape Peloro–Lake Ganzirri”, were considered Global areal geosites on the base of their tectonic origin. Lacking an official scientific report of these sites, the present research was aimed to investigate the lagoon, in order to provide the (i) geological and structural framework, (ii) inventory, and (iii) quantitative assessment of geodiversity. The study geosites resulted to be originated during the post–Wurmian sea–level rise and the strong extensional tectonics affecting the Calabria–Peloritani Arc still active. Indeed, the lagoon depression hosting the Lakes Faro and Ganzirri, developed on low-relief coasts because of different systems of capable faults, NW–SE oriented in the Lake Faro and ENE–WSW oriented in the Lake Ganzirri. The quantitative assessment of geodiversity indicated high scores for the scientific value and the potential educational and touristic uses. On the basis of these results, it was possible to confirm the attribution of Lake Faro’s and Lake Ganzirri’s geodiversity to Global areal geosites, being the study morpho-structures key localities, providing indicators of representativeness, geological diversity, and rarity that ought to be protected as clear and unequivocal examples of the Earth’s geological history and evolution of the Quaternary tectonic coastal lagoons. Actual criticisms that could irreversibly affect the environmental equilibria have been evidenced. Possible actions for the redevelopment of the oriented natural reserve of the coastal lagoon of Cape Peloro and the extension of the geosites were also described.

Multi-contamination groundwater risk assessment based on integrated OSPRC framework considering receptor and consequence components

This study evaluates the risks associated with geogenic and anthropogenic contaminants in the Azarshahr aquifer situated in the Lake Urmia watershed in NW Iran, an area critically affected by both natural mineral deposits and intensive agricultural activities. This region, characterized by its significant geological diversity and extensive use of pesticides and fertilizers, presents a unique opportunity to study the interaction between natural and human-induced groundwater contamination. Employing the Origin-Source-Pathway-Receptors-Consequence (OSPRC) framework, the research focuses on the linkage between these contaminants and waterborne diseases, particularly examining the less-studied “Receptor” and “Consequence” components using the Groundwater Quality Index (GQI) and health risk indices. Our approach integrates vulnerability assessments through the DRASTIC and SPECTR methods, enhanced by Sugeno fuzzy logic, to produce a detailed risk map highlighting two critical zones: Risk Cell 1, impacted predominantly by agricultural contaminants including nitrate and chlorpyrifos, and Risk Cell 2, affected by geogenic contaminants such as arsenic, lead, nickel, and chromium. This comprehensive analysis not only maps out the source and migration pathways of these contaminants but also evaluates their impact on human health. The findings underscore a strong correlation between identified risks and health impacts, emphasizing the pressing need for targeted health interventions and improved management of water resources in the region. By advancing the application of the OSPRC framework, this research fills a vital gap in our understanding of aquifer contamination dynamics and sets a new standard for future groundwater risk assessments.

Subsurface structural trends in Central-Western India: Inferences from magnetotelluric data using the complex MT apparent resistivity tensor

The central-western part of the Indian subcontinent exhibits significant geological diversity and possesses a rich record of different tectonothermal events in the earth's evolutionary history, spanning from the Archean to the present. Precambrian geology in the region is mostly obscured by Cretaceous-Tertiary/Paleocene volcanic eruptions and Proterozoic to Quaternary/recent sedimentary cover. Magnetotelluric (MT) impedance and tipper responses from 146 stations, covering central-western India in a grid fashion with a spacing of ∼55 km, were analyzed to evaluate the subsurface structural trends, dimensionalities, and qualitative characteristics of the electric lithosphere in the region. An advanced Complex Apparent Resistivity Tensor (CART) approach, along with the popular Phase Tensor (PT) approach and induction arrows are utilized to achieve the above goals. The analysis revealed a high degree of 3D induction effects in the data at almost every station and period. The directionality information retrieved from the tensor properties showed that the structural trends in the deep crust and upper mantle of the major geologic domains correlate with the known surface tectonic trend of the respective geologic domain. This study provides vital evidence to support the suspected bifurcation of the Precambrian Aravalli-Delhi Mobile Belt (ADMB) tectonic trend and its extensions into neighboring Kutch, Saurashtra, and Central Indian Tectonic Zone (CITZ) domains. The analysis results indicate a lithospheric scale enhanced conductivity beneath the Malwa plateau, which marks the first major phase of the Reunion mantle plume eruption in India. A critical finding of this study is that the Resistivity Phase Tensor better defines the subsurface resistivity structure and provides much clearer structural information than the conventional Phase Tensor.

Isotopic distribution of bioavailable Sr, Nd, and Pb in Chungcheongbuk-do Province, Korea

BackgroundMapping the distribution of bioavailable isotope ratios across landscapes serves as an efficient geochemical tool for delineating the origins and migration trajectories of humans and animals. Chungcheongbuk-do Province in central Korea, known for its geological diversity and inland location isolated from coastal influences, provides an ideal area to study the contributions of geological and environmental factors to the isotope landscape (isoscape). This study analyzed the distribution of bioavailable Sr, Nd, and Pb isotopes in the province using plant and soil data obtained in this study and from previous works.FindingsChungcheongbuk-do features diverse geological elements, including Precambrian basement, Paleozoic metasedimentary rocks, and Mesozoic granitoids and volcano-sedimentary sequences. The 87Sr/86Sr ratios of bulk soil samples from 44 sites primarily range from 0.781 to 0.706, with two ratios exceeding 0.9 originating from Precambrian basement and Cretaceous granitoid areas. Fractions of soils treated with 1 M ammonium nitrate and acetic acid exhibit indistinguishable 87Sr/86Sr ratios (R2 = 0.99, except for one point), spanning from 0.804 to 0.707. Plant 87Sr/86Sr ratios demonstrate a robust positive correlation with leachate ratios (for ammonium nitrate data, (87Sr/86Sr)plant = 0.938 × (87Sr/86Sr)leachate + 0.045, R2 = 0.98). The εNd values of bulk soils from Precambrian basement areas (–18 to –30) plot against Sm/Nd ratios around the reference line corresponding to 3 Ga, while other bulk soil samples (εNd = –1 to –21) align with a younger (~ 2 Ga) reference line. Plant εNd values, ranging from –4 to –24, exhibit a prominent positive correlation with ammonium nitrate leachates (plant εNd = 0.77 × leachate εNd – 3.83, R2 = 0.89). Plant samples do not show consistent variation between 87Sr/86Sr and εNd. The 206Pb/204Pb and 207Pb/204Pb ratios of bulk soils show a ~ 2 Ga trend, typical for Korean basement rocks. The Pb isotopic ratios of ammonium nitrate and acetic acid leachates match perfectly with each other (R2 = 0.99). The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of plant samples vary narrowly (19.2–17.9; 15.8–15.5; 39.0–38.0) and are distinctly different from those of bulk soils (24.4–17.9; 16.5–15.6; 42.5–37.9) and their leachates (23.1–17.7; 16.2–15.6; 41.0–38.1). Plant and soil data from this study and previous works were used to construct Sr and Nd isoscapes, employing interpolation models based on inverse distance weighting, simple kriging, empirical Bayesian kriging, and geology and topography-considered empirical Bayesian kriging regression prediction. These maps await validation through analysis of additional archives.ConclusionsThe isotope data obtained in this study highlight a strong geological control over bioavailable Sr and Nd, in contrast to a dominant environmental influence on bioavailable Pb. The Sr and Nd isoscapes presented here are potentially valuable for addressing archaeological or forensic inquiries in their current state. Nevertheless, the maps would benefit from additional refinement with increased sample density and enhanced interpolation models.

Geoarchaeology, preliminary study of relationship analysis between geological conditions and the Megalithic sites in the candidate of Ternate Geopark, North Maluku

Abstract Geopark is a concept of sustainable development with three main components: geological diversity, cultural diversity, and biodiversity, with the ultimate goal of protecting the Earth’s diversity, environmental preservation, and broader earth science education. Geological and cultural diversity in a geopark concept does not stand alone, but there is a relationship. Ternate Island is a volcanic island with Gamalama Mts as a Quaternary Volcano. The area around the volcano is comfortable because there is sufficient water despite the eruption disaster. Megalithic artefacts such as menhirs and pseudo dolmens are cultural products closely tied to the significant stone tradition. Megalithic remains on Ternate Island are represented by the presence of Jere, a local term to refer to the sacred places usually represented by menhirs and whole boulders in 56 locations. The regent government plans to develop it as an island geopark. Before being proposed, a study of geological, biological, and cultural diversity must be carried out to propose establishing a geoheritage and preparing a Geopark proposal document. This initial research uses the overlay method to identify geological conditions, determine the distribution of megalithic artefacts, and analyze their relationships.

Geologic History of the Amundsen Crater Region Near the Lunar South Pole: Basis for Future Exploration

We provide the first detailed 1:100,000 scale geomorphologic map of the ∼100 km Amundsen crater region, which is of high scientific relevance for future exploration, e.g., NASA’s VIPER mission, the Artemis program, and the Chinese International Lunar Research Station. We investigated the complex geological history of the region before and after the formation of Amundsen crater on the rims of the South Pole–Aitken (SPA) and Amundsen–Ganswindt basins. We present a new Amundsen crater formation age of ∼4.04 Ga, which, in contrast to previously derived ages, is based on non-light-plains terrain. The estimated maximum excavation depth for Amundsen crater is ∼8 km, and elevated concentrations of FeO near the crater suggest that Amundsen may have redistributed SPA-derived materials. Plains materials of various kinds were observed both inside and outside Amundsen crater and are estimated to be up to 350 m thick and ∼3.8 Ga old. A less cratered, tens of meters thick mantling unit indicates a resurfacing event ∼3.7 Ga ago. We highlight five potential exploration sites that satisfy technical constraints (such as shallow slopes, solar illumination, and Earth visibility), provide materials that can be sampled, and are capable of addressing multiple science objectives. Due to its accessibility and traversability, combined with its geologic diversity, proximity of permanently shadowed regions for studying volatile processes, and ability to address multiple science objectives, we confirm and reinforce the Amundsen crater region as a high-priority landing and exploration site.

Lithologies and Chronologic Opportunities of Materials to Be Returned From the Artemis Exploration Zone

AbstractThe Artemis exploration zone is a geologically complex region likely to host some of the oldest and as‐yet‐unstudied materials on the Moon. We review six potential Artemis landing sites (001, 004, 007, 011, 102, and 105) within candidate Artemis III landing regions ”Connecting Ridge,“ “Peak Near Shackleton,” “Leibnitz Beta Plateau,” “de Gerlache Rim,” and “de Gerlache Rim 2.” Kaguya Spectral Profiler mineral data were used to determine the average lithological composition at each landing site. Potentially accessible geologic materials, their ages and significance, and appropriate application of radiometric chronometers are discussed in reference to return samples from each potential landing site. Chronological analyses of return samples from the Artemis exploration zone will enable the anchoring of the lunar impact flux curve, determine the absolute timing of pivotal events in lunar geologic history, and reveal the geological diversity of the differentiated lunar body.

Model media learning for disaster risk reduction in the Batur UNESCO Global Geopark

The development of tourism activities in the Batur UNESCO Global Geopark has brought many tourists to visit the area. Along with increasing tourism activities, the risk of disasters in the geopark area has also increased. One thing that can be done to reduce disaster risk in the Batur UNESCO Global Geopark area is to utilize geoheritage as a learning medium for disaster risk reduction. In this study, we quantitatively described geoheritage by looking at its relationship with the priority actions of the Sendai framework. The results of the assessment of geological heritage values that have been carried out in 21 geosites of the geopark area show an interrelated relationship. Scientific, educational, tourism and degradation values of geoheritage sites have an important role in conveying information and messages related to disaster mitigation, which is in line with the objectives of Sendai's priority actions. Geological heritage sites can later be developed as an educational medium because it not only has accessibility capital, supporting facilities, good geological conditions, geological diversity, but also contains geological informationthat can be used for education and research. Developing geological disaster information within geoheritage sites in geopark areas, may be in the form of geotrails and geotourism activities with the theme of disaster mitigation and earth heritage, picture books for children based on site geoheritage information, especially those related to the introduction of geological disasters, ares also ideal to develop. A geological information center at the Batur Volcano Museum and other educational acivities that can be made within the geopark area.

Regolith mapping using airborne gamma-ray spectrometry in central Brazil

In deeply weathered terrains, with high geological diversity and scarce outcrops, the lateritic regolith features support mineral research. Predictive regolith mapping uses spatial modeling and airborne gamma-ray spectrometric data to locate weathered residual products, such as the ferruginous lateritic duricrusts found in tropical regions. Although the regolith materials exhibit qualitative similarities in their gamma-ray spectrometric responses in RGB (KThU) images, the Boolean and fuzzy approaches highlighted differences that allows for mapping the regolith weathering residual products on a wide geodiversity protoliths. Two inference systems were used, one identified the ferruginous lateritic duricrusts and oxisols derived from the felsic/pelitc and mafic rocks types (TP test procedures), and the other identified solely those derived exclusively from mafic rocks (TPM test procedures). Cutoff values for the conjunction eTh/K ∩ eU/K ∩ eTh ∩ K (TP-4) using Boolean logic, provided the most accurate regolith map (accuracy = 95%) among the various tests carried out and indicate that in 28.6% of the total study area, there are lateritic duricrust and oxisols relative to rocks, saprolites, mottled horizons and other soils type. The eTh cutoff value > 4.4 ppm was used to exclude mafic rocks and associated soils, and the K value < 1.3% to exclude rocks with eTh/K and eU/K values similar to the lateritic duricrusts and oxisols. For mapping the lateritic duricrusts derived exclusively from the mafic rocks the conjunction of eTh ∩ eU/K ∩ eTh/K ∩ K ∩ eU (TPM-3) fuzzified by the large membership function was the most efficient. The eU variable with values < 1.21 ppm helps improve the effectiveness of this procedure. The generated predictive map indicated that in about ∼12% (657.9 km2) of the total study area, there are lateritic duricrusts and oxisols derived from mafic rocks. Therefore, a successful method of mapping vast areas from complicated lateritic regolith mosaic derived from a large geodiversity is to apply specific plugins for data fuzzification, supported by observations from field outcrops.

CPTU-based permeability evaluation of clays

The piezocone penetration test (CPTU) is an efficient in-situ testing method for delineating subsurface stratigraphy and interpreting geoparameters continuously with depth. However, owing to the regional sensitivity and geological diversity, the applicability of CPTU-based geotechnical parameter evaluation methods is limited when applied to specific sites. This requires further scrutiny considering the different geological histories and local soil conditions. In this study, a database that included a collection of CPTU test sites in Jiangsu Province, China, was compiled containing high-quality sampling and laboratory testing performed to characterize the permeability of clay soils. Several published CPTU correlations for determining soil permeability were summarized and compared with laboratory-measured soil permeability as a benchmark reference. The evaluation results indicated that the I c-based correlations can provide a reasonably good determination of the permeability for the investigated soils with root mean squared error of 0.89 and mean absolute error of 0.77. Finally, a modified approach was presented to evaluate the permeability coefficient of Jiangsu clay soils, which was calibrated using two additional case studies.

Geotourism of Telomoyo Volcano complex: an in-depth analysis for future development

Indonesia is located between the three world tectonic plates, the Eurasian Plate, the Indo-Australian Plate and the Pacific Plate. The collision of these three plates creates a series of volcanoes and tectonics activity in various regions, especially the subduction of the Indo-Australian Plate in southern Java. This subduction forming a row of tertiary-aged volcanoes in the south of the island of Java and quaternary in the central part of the island of Java. One of the Quaternary Volcanoes on the island of Java that is extends in a northwest-southeast, the volcanoes are Ungaran - Telomoyo - Merbabu - Merapi. The use of the geotourism analysis method is used to develop the existing geotourism potential in the Telomoyo Volcano Complex by carrying out a geodiversity inventory carried out through field activities to collect geological component data in the research area. The data collected is minerals, rocks, geological and morphological structures or landscapes that include several stages of work include categorization, assessment, evaluation, clustering and determination of geodiversity. This work is accomplished by identifying geoheritage to increase geological diversity into geological heritage through the stages of determining geodiversity and then classified to determine the status, value, meaning and function of geoheritage. The score ranking carried out to determine the geoheritage ranking by comparing the geotourism of the research location with the geotourism of other locations. The Telomoyo Volcano Complex holds a variety of unique and interesting geological phenomena so it had a promising geological conservation-based tourism potential. However, the lack of public knowledge about the potential for geology-based tourism or geotourism has caused the development of this tourism potential to be less than optimal and less desirable. Education, development and good management of the tourism sector are needed so that the potential of geotourism can be recognized by the wider community and can have a good impact, especially for the surrounding community, especially in the economic field.

Enhancing conservation and management of mountain area through a biocultural diversity evaluation approach:A case study of Taishan Mountain Area, China

As hotspots of biocultural diversity (BCD), mountain areas contain the richest ecosystems with cultural characteristics. However, in the context of cultural homogenization and ecological decline, some high-value mountain areas are still not adequately protected, and some protected areas (PAs) even suffer from an imbalance between natural and cultural protection. To improve the coverage and conservation effectiveness of PAs in mountain areas, we propose a BCD evaluation approach to identify conservation gaps and prioritization, taking the Taishan Mountain Area (TMA) as a study case: first, we used four biodiversity factors (topographic diversity, geological diversity, ecosystem services, bird species distribution) and four cultural diversity factors (cultural landscape, intangible cultural heritage, traditional production modes, population and economy) to evaluate the BCD values; second, we generated a map of BCD hotspots and graded them into three levels; and finally, we compared the evaluation result with the PAs’ layout in the TMA and determined the conservation gap and prioritization. We find that 43.92% of the high BCD areas and 84.39% of the medium BCD areas within the mountain area are inadequately protected, and 10.79% of the low BCD areas may be overprotected, classifying the above conservation gaps as three priority levels of conservation. Our study indicates that the current PAs in mountain areas are insufficiently protected and urgently need to be expanded; (2) by analyzing the coupling relationship between biodiversity and cultural diversity, it is found that only 23.90% of the relationships between the two were coordinated or above in the TMA; (3) we propose the optimization strategies of four typical conservation gaps in the TMA; (4) we finally develop an integrated conservation model of biological and cultural values for different PA categories in mountain areas based on a gap analysis. Optimizing mountain conservation and management based on the BCD evaluation results is conducive to promoting the sustainable development of human beings and nature while guaranteeing the unbiased allocation of conservation resources in mountain areas.

Occurrence, distribution, and composition of black sand along the Red Sea, Egypt

Black sand along the Red Sea is often composed of volcanic minerals and heavy minerals. The Red Sea region is known for its unique geological features, and black sand beaches can be found in various areas along its shores. The study presents a comprehensive semi-quantitative chemical analysis of black sand samples collected from various locations along the red sea, revealing significant variations in their elemental compositions. The main oxides were identified in each sample, determined through X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses, indicate diverse mineralogical compositions. The spatial distribution of minerals at each site is depicted through mapping. Additionally, Fourier-transform infrared (FTIR) spectra offer information on the functional groups present in the samples, revealing the existence of hydroxyl groups, aliphatic compounds, and adsorbed water molecules. For Qusier-Elsharm Alqbly, Safaga, Marsa Alam, Gabal Alrosass, Hurghada Titanic, Hurghada Elahiaa, Gemsa, and Ras Elbehar samples, the results highlight the presence of various minerals, such as Quartz, Calcite, Titanium Dioxide, Magnetite, Hematite, Aluminum Oxide, Zirconium Dioxide, Chromium (III) Oxide, and others, providing insights into the geological characteristics of each location. The differences in mineral content among the examined sites are linked to the geological and mineralogical makeup of the source rocks upstream and midstream in the basins that discharge into the surveyed regions. So, variations in black sand concentrations among different locations offer insights into the geological and mineralogical diversity of the studied areas along the Red Sea coast. This study addresses the existing knowledge gap by focusing on the preliminary exploration and description of the occurrence, distribution, and composition of black sand along the Red Sea in Egypt. whereas the results provide valuable insights into the geological diversity of black sand deposits in the surveyed areas, underscoring the need for additional research and interpretation of these variations. Therefore, the in-depth examination of mineralogical composition and crystal structures establishes a foundation for future investigations in the field of geology and earth sciences.

The Escarpão Plateau (South of Portugal)—a Study Case of Nested Geosites from the Aspiring Algarvensis Geopark

Located along the southern limit of the Algarvensis aspiring UNESCO Global Geopark (aUGGp), the Escarpão Plateau is a singular geomorphological structure sculpted by fluvial, karst, and tectonic processes. The plateau is deeply scarved by the Quarteira Rivulet, forming a valley that crosses the most complete Upper Jurassic sedimentary sequence of the Eastern Algarve (Southern Portugal). This sequence includes five geological formations representing different depths of carbonate ramp deposition from the Tethys Sea: Peral Formation, Jordana Formation, Cerro da Cabeça Formation, Escarpão Formation, and the upper Limestone Formation with Anchispirocyclina lusitanica (foraminifera), respectively from the oldest formation to the most recent at the top. Throughout the Quaternary Period, the karst processes shaped a landscape of sparse and poor soils, based on which successive generations adapted their subsistence agriculture and way of life. The geomorphology of the plateau and the rivulet valley, the sequence of the carbonated formations, and the diversity of sedimentary and paleontological records can be considered possible sites of diverse geological interest and with different scales that are embedded in each other, forming thus nested sites. To promote and preserve these sites, the Algarvensis aUGGp shaped an 8-km-long interpretative walking path, passing through 11 points of interest, including biosites and geosites. Their interpretative boards highlight not only the different spatial and temporal geological diversity but also its relationship with surrounding cultural and historical heritage. Finally, this work allowed the creation of new products for outreach and public awareness towards an effective geoconservation.

The linkage of geological parameters to cultural diversity at Karangsambung-Karangbolong Geopark and surrounding area, Kebumen, Indonesia

Geopark has three main components: geological, biological, and cultural diversity. Cultural and biological diversity in geoparks does not stand alone but must be related to geological diversity. This study aims to determine the relationship between seven geological criteria (lithology, mining materials, elevation, slope, landscape, river distance, and groundwater/geohydrology) on the formation of culture in the Megalithic, Hindu-Buddhist, Islamic, and Colonial eras in the Karangsambung-Karangbolong Geopark and surrounding area. The analytical method used is a scoring and weighting process using Analytical Hierarchy Processes (AHP). Based on AHP analysis, many relationships exist between culture formation and geological conditions. In the early stages of cultural formation during the Megalithic and Hindu-Buddhist eras, the influence of geological criteria was more dominant than that in the Islamic and Colonial eras. In the Megalithic era, groundwater had an effect of 32.38%, with the main sub-criteria being wide productive aquifers, while river distance had an impact of 28.31%, especially at river distances less than 50 m. The very well-suited area correlated with the geological condition and had the highest percentage (29.03%). In the Hindu-Buddhist era, groundwater conditions were influenced by 36.05%, mainly due to the wide productive aquifer as a sub-criterion, while the distance of the river had an effect of 25.78%, especially when the river's length was less than 50 m. The percentage of the very well-suited area was 27.47%. The elevation criteria had a 34.68% influence in the Islamic era, especially at elevations <5 m. Mining material criteria influenced 24.34%. The level of very well-suited areas was 14.45%. The geomorphology had the most significant influence (37.17%) in the Colonial era, especially in the fluvial and marine landscapes. Mining materials had the second influence (24.18%). The very good suitability area accounted for 25.54%.

The dilemma of valuing geodiversity: geoconservation versus geotourism.

Geodiversity and geosystem services are confronting global threats. However, the majority of conservation strategies tend to overlook the geological component within ecosystems. The existing literature centres on biodiversity, ecosystem services and theireconomic valuation. In this paper, we conduct a systematic literature review to identify the gap in the assessment of geological diversity, pinpointing areas where scientific contributions are needed to safeguard geological resources. Our findings reveal a concentration of studies assessing geodiversity in European and Asian countries. While the majority of the reviewed papers emphasizes the recreational features and associated values of geological resources, promoting geotourism and recognizing its potential for economic growth, there is a significant oversight concerning the impact of tourism on geological resources. Existing assessments predominantly focus on visitors' perceptions and preferences, sidelining the inhabitants' perspective and their crucial roles in the conservation of geodiversity. This article is part of the Theo Murphy meeting issue 'Geodiversity for science and society'.

The possibility of spatial mapping of SOC content in olive groves under integrated production using easy-to-obtain ancillary data in a Mediterranean area.

Unlike most of Europe, Andalucía in southern Spain as a Mediterranean area still lacks digital maps of SOC content provided by machine learning algorithms. The wide diversity of climate, geology, hydrology, landscape, topography, vegetation, and micro-relief data as easy-to-obtain covariates facilitated the development of digital soil mapping (DSM). The purpose of this research is to model and map the spatial distribution of SOC at three depths, in an area of approximately 10000 km 2 located in Seville and Cordoba Provinces, and to use R programming to compare two machine learning techniques (cubist and random forest) for developing SOC maps at multiple depths. Environmental covariates used in this research include nine derivatives from digital elevation models (DEM), three climatic variables and finally eighteen remotely-sensed spectral data (band ratios calculated by the acquired Landsat-8 OLI and Sentinel-2A MSI in July 2019). In total, 300 soil samples from 100 points were taken (0-25 cm). The purpose of this research is to model and map the spatial distribution of SOC, in an area with approximately 10000 km2 located in Seville and Cordoba Provinces, and to compare two machine learning techniques (cubist and random forest) by R programming. The findings showed that the novel approach for integrating the indices using Landsat-8 OLI and Sentinel-2A MSI satellite data had a better result. Finally, we obtained evidence that the resolution of satellite images is more important in modelling and digital mapping.

Geological History of Caves and Conservation Values of the World Nature Heritage Phong Nha-Ke Bang National Park

The long development history and geological diversity of the Phong Nha-Ke Bang area is shown by the rich and diverse lithological composition of the stratigraphic units ranging in age from Devonian to Present day: granite, terrigenous rock, thin-bedded limestone, and massive limestone. The geomorphology of the national park includes limestone mountain terrain alternating with terrigenous rock mountain terrain surrounding the karst valley system. The formation of the cave is an endogenous-exogenous geological process that occurs according to the cycle of global sea level change. The tectonic activity is the mother that gives birth to the caves of different heights and ages. The higher the cave, the older it is, and the oldest cave is 32 million year old-Khe Ry cave. The four fault systems of Northeast - Southwest (NE-SW), Northwest - Southeast (NW-SE), West - East (WE), and North - South (NS) create four cave systems that are deep faults with strong destructive intensity. Exogenous geological activities in the cave have created a uniquely beautiful landscape including three simultaneous processes: i) Chemical washing of driftwood, mechanical abrasion, polishing of the cave walls, and ceiling caused by travertine floods pouring into it from outside the cave; ii) Precipitation forming stalactites from the ceiling of the cave and precipitation forming stalagmites from the floor of the cave slowly over millions of years; and iii) Travertine sedimentation on the cave floor resulting in many unique sedimentary bodies, specifically filling the rough terrain of limestone blocks, covering the ancient stalactites falling from the cave ceiling, forming spiral mushroom island in the Son Doong cave, and creating gem pebbles located in fan-shaped sunken cells of the cave.&#x0D;