Petrological Characteristics Research Articles

Towards a Dynamic Optimisation of Comminution Circuit Under Geological Uncertainties

Geometallurgical programmes are crucial for designing mineral processing plants that maximise comminution throughput. However, the variability of complex ore bodies, such as platinum group element (PGE) deposits, poses challenges in developing these programmes into profitable mine-to-mill production. This paper investigates the geological characteristics of different lithologies hosting the complex PGE orebody located in the Northern Limb of the Bushveld igneous complex in South Africa and assessed their impact on metallurgical efficiency in comminution circuits. Regression machine learning techniques were employed to analyse the ore mineralogical dataset from two lithologies (feldspathic pyroxenite and pegmatoidal feldspathic pyroxenite) and predict the Bond Work Index (BWI), a key comminution parameter for calculating processing plant throughput. The results indicated that BWI is strongly influenced by Chlorite, silicates, iron oxides, and the relative density of the PGE deposit. Using both simulated and laboratory-measured throughput values, a particle swarm optimisation (PSO) algorithm was applied to maximise the plant’s comminution throughput through tactical blending of low-grade and high-grade ore stockpiles. The PSO algorithm was shown to be an effective tool for stockpile management and tactical mine-to-mill operation in response to feed mineralogical variability. This first-time innovative approach addresses complex geological uncertainties and lays the groundwork for future geometallurgical studies. Potential areas for further research include incorporating additional lithologies for tactical ore stockpile blending and optimising parameters critical for ore mineral flotation.

The geochemical and organic petrological characteristics of kolm (upper Cambrian, Sweden): Implications for genesis

The geochemical and organic petrological characteristics of kolm (upper Cambrian, Sweden): Implications for genesis

Raman Spectroscopy and Imaging Techniques Applied to Neolithic Artefacts as a Valuable Contribution to the Archaeological Research on Piacentine Sites

Archaeologists and conservation scientists join interdisciplinary projects aiming at the in-depth analysis of artefacts and the resolution of new archaeological issues, overcoming the common limits of mesoscopic observation. The aim of this research is to perform multidisciplinary research, adapting imaging techniques (RTI imaging and 3D photogrammetry) and Raman spectroscopy from their conventional field of application to study and valorise neolithic archaeological findings from Piacentine sites (Emilia-Romagna, Italy). RTI images enable the detection of a comprehensive framework of anthropic and natural traces on the object surfaces to support the hypothesis of the intended usage of artefacts. Combining qualitative and quantitative Raman spectra analysis, the specific lithological characterisation of each fragment is conducted, thereby the understanding of their probable geographic provenance is enhanced. This contributes to the identification of the External Ligurian Units as a possible primary supply area, along with the already known outcrops in the Mont Viso Massif and Voltri Group. Their potential as a powerful instrument for conservation and valorisation has been revealed by 3D models. In fact, they may enrich museum exhibits, enhancing visitors’ experience through interactive engagement and guarantee the examination of artefacts by experts across the globe through online sharing, without the need for transportation and excessive manipulation.

Analyzing the influence of urban vegetation cover on land surface temperature in Southwestern Nigeria

Urbanization and the expansion of urban infrastructure have led to the development of new land use policies that impact biodiversity and ecosystem services in Nigeria’s rapidly growing cities. Key drivers of this urbanization include population pressure, infrastructure development, rural-to-urban migration, and economic growth. This study investigates the effect of urban vegetation cover on land surface temperature in southwestern Nigeria, using the spectral radiance method, the support vector machine (SVM) algorithm and the normalized difference vegetation index (NDVI). This study analyzed remote sensing data to classify land use changes from 1991 to 2021 based on lithological characteristics. Additionally, the urban vegetation covers (VC) of the two urban centres were assessed through NDVI analysis. The highest NDVI values was recorded in Akure 0.358 to 0.394, and Osogbo had 0.449 to 0.464 while the lowest for Akure − 0.052 to 0.005 and Osogbo had − 0.058 to − 0.009. The analysis of urban land surface temperatures from 1991 to 2021 indicated maximum temperatures of 29.53 to 34.22 °C in Akure and 31.11 to 36.85 °C in Osogbo, with minimum temperatures of 18.22 to 22.48 °C in Akure and 21.72 to 23.66 °C in Osogbo. Primarily, urban land surface temperatures have steadily increased in both cities due to deforestation and urban infrastructural development which have diminished vegetation cover. This research highlights the need for urban green infrastructure and effective planning strategies to mitigate the impacts of rising land surface temperatures.

Groundwater Contamination: Study on the Distribution and Mobility of Metals and Metalloids in Soil and Rocks

This study investigates the distribution and mobility of metals and metalloids (M&Ms) in soils, rocks, and groundwater within the geologically complex southwestern region of Sicily. The study aims to highlight how natural sources, like rocks and soils, can release elements potentially harmful to human health. It underlines their dual role as both natural reservoirs and active sources of M&M release, driven by leaching processes influenced by physicochemical factors such as pH and redox potential (Eh). Lithological characteristics significantly influence the retention and release of elements, with clay-rich formations exhibiting higher immobilization capacity. However, environmental parameter variations can enhance element mobilization, increasing bioavailability and the risk of groundwater contamination. Water quality analyses reveal regulatory exceedances for As, B, Ni, and Be, underscoring potential health and ecological risks. Concurrently, microbiological investigations identify diverse microbial communities capable of altering the oxidative states of specific elements through oxidation and reduction processes, further influencing their mobility. This study underscores the importance of understanding natural sources of M&Ms and their interactions with geochemical and microbiological processes for effective environmental risk assessment. The findings provide a foundation for developing integrated and sustainable water resource management strategies to mitigate contamination risks and safeguard ecosystems and public health.

ADVANCING PLANETARY SUSTAINABILITY THROUGH LITHOLOGICAL MAPPING: ASTER REMOTE SENSING IN ANTARCTICA’S DRY VALLEYS

The Dry Valleys of South Victoria Land in Antarctica, one of the most extreme deserts on Earth, offers an unparalleled analog for Martian landscapes and a vital record of Earth's geological history. Characterized by a cold, arid climate and minimal atmospheric moisture, the region's ancient rock formations, including early Paleozoic granitoid plutons, Devonian to Triassic sedimentary rocks of the Beacon Supergroup, and Jurassic basalt flows, provide insights into Earth's evolution. The logistical challenges of traditional field-based geological surveys in this remote and fragile environment emphasize the need for sustainable exploration methods. This study leverages Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) remote sensing technology to achieve high-resolution lithological mapping while minimizing environmental impact. Image processing techniques such as Band Ratio (BR) analysis, Principal Component Analysis (PCA), and the Optimal Index Factor (OIF) were employed to enhance the spectral characterization of lithologies. These approaches facilitated the identification of key lithological units, including sandstone, granite, gneisses, and basaltic flows, and the production of an accurate lithological map. By integrating remote sensing with sustainable scientific practices, this research demonstrates the potential to advance planetary sustainability while uncovering critical geological insights in extreme environments.

Predicting Manganese Mineralization Using Multi-Source Remote Sensing and Machine Learning: A Case Study from the Malkansu Manganese Belt, Western Kunlun

This study employs multi-source remote sensing information and machine learning methods to comprehensively assess the geological background, structural features, alteration anomalies, and spectral characteristics of the Malkansu Manganese Ore Belt in Xinjiang. Manganese mineralization is predicted, and areas with high mineralization potential are delineated. The results of the feature factor weight analysis indicate that structural density and lithological characteristics contribute most significantly to manganese mineralization. Notably, linear structures are aligned with the direction of the manganese belt, and areas exhibiting high controlling structural density are closely associated with the locations of mineral deposits, suggesting that structure plays a crucial role in manganese production in this region. The Area Under the Curve (AUC) values for the Random Forest (RF), Naïve Bayes (NB), and eXtreme Gradient Boosting (XGBoost) models were 0.975, 0.983, and 0.916, respectively, indicating that all three models achieved a high level of performance and interpretability. Among these, the NB model demonstrated the highest performance. By algebraically overlaying the predictions from these three machine learning models, a comprehensive mineralization favorability map was generated, identifying 11 prospective mineralization zones. The performance metrics of the machine learning models validate their robustness, while regional tectonics and stratigraphic lithology provide valuable characteristic factors for this approach. This study integrates multi-source remote sensing information with machine learning methods to enhance the effectiveness of manganese prediction, thereby offering new research perspectives for manganese forecasting in the Malkansu Manganese Ore Belt.

Deep hydrocarbon charging and accumulation in complex fault blocks, the northern part of the eastern Liaohe depression, China

Deep exploration in complex fault-block regions is critical for global oil and gas development. As a representative region characterized by complex fault-block development, the northern part of the eastern Liaohe depression poses challenges in understanding the charging time and migration channels of deep hydrocarbons due to its intricate structural and reservoir conditions. For this purpose, this study utilizes diverse geological data from recent explorations, employing the petrological characteristics of inclusions, homogenization temperatures, and simulations of the thermal burial history to investigate the charging times of deep hydrocarbons. It combines the diagenetic processes of the reservoir with tectonic evolution to reveal the charging pathways and dynamic processes of deep hydrocarbons in the northern part of the eastern Liaohe depression. The results indicate that there are two charging periods in the study area: the late Oligocene (32.9–27.5 Ma) and from the late Neogene to the present (8.7–0 Ma). During these critical periods, faults with high activity intensity and low fault section normal stress were in an open state, which can serve as pathways for the vertical long-distance migration of hydrocarbons. In the first charging period, a substantial volume of hydrocarbon expelled from the source rocks migrates vertically into the deep sandstone reservoir through opening faults, exhibiting characteristics of source–reservoir separation. Subsequently, a brief uplift at the end of the Oligocene halted hydrocarbon generation. In the second charging period, as the source rocks further matured, a substantial volume of natural gas was injected into the deep reservoirs. At this period, the faults approached the seal, preventing hydrocarbons from migrating vertically and allowing them to enter the deep sandstone reservoirs adjacent to the source rocks, reflecting characteristics of source–reservoir proximity.

Quantitative reservoir evaluation and hydrocarbon volumetrics :an integrated petrophysical and 3-D static modeling approach in ‘Hamphidex’ field, Niger-Delta, Nigeria

The viability and hydrocarbon volumetrics of the Hamphidex field reservoirs were evaluated using petrophysical analysis and three-dimensional (3D) static modeling of three key reservoir sands (X, Y, and Z). The petrophysical analysis involved detailed characterization of lithologies, net-to-gross ratios, porosity, hydrocarbon saturation, water saturation, and permeability. The volumetric attributes of the field were derived from the constructed 3D reservoir models. Two geostatistical methods—Sequential Gaussian Simulation (SGS) and Sequential Indicator Simulation (SIS)—were utilized for facies and property modeling, focusing on porosity and permeability. Comprehensive facies models and petrophysical property models were developed for each reservoir sand (X, Y, and Z), integrating 3D visualizations of facies distributions, porosity, permeability, water saturation, and fluid contact models. These models also included cross-sectional views, providing a detailed spatial representation of the reservoir's characteristics. Two main facies, sand and shale, were identified, with sand acting as the hydrocarbon reservoir. Well-log correlations in six wells (Hamdex-02, 06, 01, 05, 04 and 07) of the field show that sands X, Y, and Z have lateral continuity and their hydrocarbon potential varies between wells. Specifically, Sand ‘X’ contains hydrocarbons in Hamdex-05 and Hamdex-07, Sand ‘Y’ is hydrocarbon-rich in Hamdex-05, and Sand ‘Z’ shows hydrocarbon presence in Hamdex-06, Hamdex-05, and Hamdex-04. These hydrocarbons are confined within an anticlinal structural trap that closes on a fault. For Sand X, Y, and Z, porosity values range between 16 and 25%, permeability varies from 10 to 1600 mD, water saturation lies within 7 to 50%, and hydrocarbon saturation spans from 50 to 93%. The volumetric assessments from the build models showed that Sand X, Y and Z have Stock-Tank-Oil-Initially-In-Place (STOIIP) of 75.864, 8.566 and 80.177 Million Barrels (MMbbl) respectively. In addition to Sand Y STOIIP it also has Gas-Initially-In-Place (GIIP) of 14.870 Billion Standard Cubic Feet (Bscf). The analysis indicates that the field contains substantial hydrocarbon reserves, with the petrophysical properties confirming the reservoirs' high quality. These findings demonstrate that the field is economically viable and suitable for development, presenting a strong potential for successful exploitation.

Petrology of the Sandstone-Type Uranium Target Layer and Its Uranium Existence Form in the Telaaobao Mineral Area, Ordos Basin.

In recent years, the Telaaobao Mineral Area in the Northwestern Ordos Basin has been newly discovered as a uranium mineralization area with its ore-bearing target layer located within the Lower Cretaceous Huanhe Formation, belonging to a new area and a new layer, and has great uranium deposit formation potential. In order to deeply study the issues of the ore-bearing target in this area, such as the petrology, mineralogy, and uranium mineralization of the ore-bearing sandstone, based on the data from field geological investigation and drill core logging, the petrological characteristics of the ore-bearing sandstone of the target layer are preliminarily interpreted using a polarizing microscope and a scanning electron microscope, and the uranium mineral composition, uranium occurrence state, and uranium deposit mineralization are investigated through the electron probe microanalysis technique in this paper. The results show that the target layer sandstone in the study area has the characteristics of proximal deposit and has undergone significant epigenetic alteration and transformation, producing favorable conditions for uranium- and oxygen-containing water transportation and uranium mineralization. The uranium minerals are dominated by the independent coffinite with the UO2 content ranging from 40.93 to 60.45%, followed by the titanium-uranium oxides. The uranium minerals occur in various forms, mainly in the edge or fissure of the debris particles, in the edge of the framboidal pyrite, around the biotite or within its cleavage fissures, and on the surface of the chlorite. In addition, a preliminary uranium mineralization model was also established in the Telaaobao Mineral Area. The uranium mineralization in the Telaaobao Mineral Area results from the combined action of the infiltrating and ascending fluids. The uranium- and oxygen-containing fluids from the source area infiltrate downward into the target sandstone layer and meet the ascending reducing fluids from the depth, producing a redox barrier in Huanhe Formation, within which U6+ is reduced to U4+ for precipitation, leading to the formation of uranium mineralization.

First Constraints on the Pressure–Temperature–Time Evolution of the Vijayan Complex, Sri Lanka: Implications for Its Position in Gondwana

ABSTRACTSri Lanka occupies a pivotal geological position within East Gondwana, featuring four prominent high‐grade Precambrian lithotectonic units: the Highland Complex (HC), the Wanni Complex, the Vijayan Complex (VC) and the Kadugannawa Complex. Despite reasonable geochemical and geochronological investigations into rocks in the VC, a comprehensive understanding of their petrological characteristics, particularly their pressure–temperature–time evolution, remains limited, impeding accurate terrane correlations. In this study, a detailed analysis of mineral assemblages, reaction textures, and U–Pb zircon ages in samples collected from the eastern margin of the HC to the eastern coast, in the VC were conducted. Results indicate that the VC preserved textural evidence for prograde dehydration reactions indicating upper amphibolite to granulite facies transition. The peak metamorphism is followed by a stage of near isobaric cooling stage. Conventional geothermobarometric analysis coupled with phase equilibria modeling of VC gneisses reveal peak metamorphic P–T conditions of 790°C–830°C and 7–8 kbar. Retrograde metamorphism has occurred until the temperature decreased to 740°C. The U–Pb zircon dates at ca. 1010–960 Ma suggest protolith ages of the VC coinciding with Rodinia amalgamation and dispersal, aligning metamorphic thermal peaks at ca. 575–545 Ma with the Kuunga orogeny during Gondwana amalgamation. Our data signifies connections between the VC and both the Lurio foreland in Mozambique and the Innhovde Suite and Yamato‐Belgica Complex in East Antarctica, however, the differences in metamorphic conditions and geochronological signatures necessitate further investigation into its tectonic history and paleogeographic evolution.

New insight into the controlling factors of differences in carbonate buried-hills driven by tectonic activity: a case study of the Weixinan Sag, Beibuwan Basin, China

As the main field for crude oil exploration in the western of the South China Sea, the Weixinan Sag, Beibuwan Basin, has discovered multiple hydrocarbon-bearing structures. Carboniferous carbonate buried-hills in the Weixinan Sag, as a new field for increasing oil reserves and production, have enormous potential for exploration. Due to the influence of karstification, carbonate buried-hill reservoirs exhibit strong heterogeneity and rapid changes in physical properties, making the exploration of effective reservoirs more difficult. In this study, drilling cores and resistivity imaging logging data were employed to investigate the petrological characteristics and fracture development patterns of buried-hill reservoirs. By processing and calculating well logging curves, the development characteristics and vertical distribution patterns of karst in buried-hill reservoirs can be effectively displayed. Based on this, divide karst facies zones, measure karst thickness, and analyze their distribution patterns. The results indicate that tectonic activity is the main controlling factor for the karst differences in carbonate buried-hills in the Weixinan sag. the carbonate buried-hills karst in the No. 1 and No. 2 fault zones has characteristics of vertical zoning, plane partitions, and multiple phases. The buried-hills in the No. 1 fault zone have more karst stages and effective karst storage space than the buried-hills in the No. 2 fault zone. We propose four karst types under the control of tectonic activities, and establish a development model for the karst in the Weixinan Sag buried-hills. This study provides significant guidance for the development and reservoir prediction for similarly carbonate buried karst hills.

Enhanced subsurface investigation utilizing electrical resistivity tomography and precise positioning tools (study case: Rongga landslide)

This study presents an enhanced approach for subsurface investigation using Electrical Resistivity Tomography (ERT) coupled with precise positioning tools, focusing on the Rongga Landslide in Indonesia. ERT is widely recognized for its ability to map subsurface conditions by detecting resistivity contrasts associated with geological structures and water content, especially in landslide-prone areas. The study combines GPS and digital waterpass altimeter with ERT to improve the precision of subsurface anomaly detection. Important information regarding moisture distribution, graben structures, and sliding surfaces was revealed by the generation of two ERT profiles. Our research indicates that a number of factors, including lithological characteristics, erosion along riverbanks, and tectonic activity—specifically, a nearby fault structure—may have contributed to the Rongga landslide These findings highlight the usefulness of ERT to evaluate the risk of landslides and offer useful data for geotechnical research in tectonically active areas.

Study of the relationship between uniaxial compressive strength and the point load index test in rocks from the bank in Seybaplaya Campeche Mexico

The present research focuses on analyzing the uniaxial compressive strength of rocks and its relationship with point load index testing. It is important to note that Seybaplaya, located in Campeche Mexico, is recognized for its fishing, industrial and commercial activities and where a rock bench is located from which samples were obtained to carry out the study. As a result, equations were developed that allow predicting the simple uniaxial compressive strength based on the values obtained from the point load index test. It is relevant to highlight that these relationships are valid only for rocks with lithological characteristics similar to those used in this study. The analysis results and conclusions demonstrate the linearity of the relationships between the simple uniaxial compressive strength and the point load index test.

Determining tectonic fault characteristics in oil and gas field structures using Juxtaposition diagrams: a case study of the Darvin Bank

The type of tectonic faults plays an important role in issues such as migration and accumulation of hydrocarbons, formation of traps, determination of the direction of prospecting and exploration works, preparation of development projects, etc. For this reason, determining the characteristics type of tectonic faults in the exploration, development and exploitation of oil-gas fields is one of the main problems. There have been a number of approaches communicated both internationally and in local Azerbaijani publications. Juxtaposition diagrams, which are drawn up by taking into account the spatial position of faults and lithological characteristics of the surrounding sediments, are widely used in the search for fault-related traps and in the separation or integration of production objects in fields. It is also possible to determine the amount of shale material entering the fault gouge with these graphs. Considering that the Darvin Bank field is complicated by tectonic faults, the juxtaposition diagrams proposed by Knipe R. J. were used to determine the connection between the tectonic blocks. According to Upper Kirmaki Suite (KSupper) horizon, the faults numbered 11 and 3a in the northwest part of the field are permeable, while faults numbered 3, 6, and 7 are classified as non-permeable. The reliability of the results has been confirmed by the results of Cluster analysis applied in previous studies, and the application of this method in other oil and gas fields of Azerbaijan has been suggested. Keywords: fault characteristics; permeable or sealing faults; Juxtaposition diagrams; production objects; Cluster analysis; shale gouge ratio.

Study of the relationship between uniaxial compressive strength and the indirect tensile test (BTS) in rocks from the bank in Seybaplaya Campeche Mexico

The present research focuses on analyzing the uniaxial compressive strength of rocks and its relationship with the indirect tensile test (the Brazilian method). It is important to note that Seybaplaya, located in Campeche, Mexico, is known for its fishing, industrial and commercial activities, and is home to a rock bank from which samples were obtained for this study. As a result, an equation was developed that allows predicting the simple uniaxial compressive strength from the values obtained in the indirect tensile test. It should be noted that this relationship is valid only for rocks with similar lithological characteristics of the samples analyzed. The results of the analysis and conclusions show the linearity of the relationship between the simple uniaxial compression resistance and the indirect tensile test.

Lithological characterization of the subsurface layers at ‘NASS’ field, Choba, Rivers State

Lithological characterization of the subsurface layers at ‘NASS’ field, Choba, Rivers State

Study on sedimentary model of Shanxi Formation – Lower Shihezi Formation in Da 17 well area of Daniudi gas field, Ordos Basin

Abstract The Daniudi gas field in the Ordos Basin is a significant area for developing tight sandstone gas reservoirs in China. This study focuses on the Permian Shanxi and Lower Shihezi formations in the Da 17 well area, analyzing sedimentary model through petrological characteristics, physical properties, pore characteristics, and lithofacies characteristics. Findings reveal that the Shanxi Formation belongs to the deltaic plain sedimentary environment, which is divided into distributary channel and inter-channel, and identifies the microfacies of the main distributary channel and the sub-distributary channel. The Lower Shihezi Formation exhibits braided channel sediments, dividing them into channel bar sediments and flood plain sediments, and identifying isolated channel microfacies and superimposed channel microfacies. Analysis shows that sedimentation has an impact on reservoir properties through particle size, lithological characteristics, and sedimentary microfacies. The main distributary channel and superimposed sandbars are favorable microfacies for the formation of gas reservoirs. The porosity of the main diversion channel ranges from 8 to 13%, and the permeability ranges from 0.3 to 0.6 × 10−3 m2. The porosity of the superimposed sandbar ranges from 8 to 15%, with a permeability of 0.3–2.2 × 10−3 m2. This study provides a theoretical foundation advancing tight sandstone gas development in the Daniudi gas field.

The Reservoir Characteristics Analysis of the G162 Area in the Jiyuan Oilfield, Yan 9 Segment.

The G162 block of Jiyuan Oilfield in the Yan 9 segment has good exploration prospects, with multiple drilling wells yielding high industrial oil flow. However, current research on the reservoir characteristics of the Yan 9 segment in the G162 block is relatively weak, which has hindered the progress of exploration and development. To clarify the reservoir development characteristics of the Yan 9 segment in the G162 block of Jiyuan Oilfield, this study takes the reservoir of the Yan 9 segment in the G162 block of Jiyuan Oilfield as the research object, and conducts a study on the petrological characteristics, physical properties, and pore structure of the reservoir rocks by combining core samples, thin sections, physical properties, and high-pressure mercury injection data. The results show that the permeability and porosity of the Yan 9 segment reservoir vary greatly, with medium-sized pores and moderate permeability predominating, and the overall pore structure is relatively good. Based on the physical property data, types of pores, the curve shapes of high-pressure mercury injection, and various parameters, the pore structure of the Yan 9 segment reservoir is classified from good to poor into three types: Ⅰ, Ⅱ, and Ⅲ. The study area is mainly dominated by Type Ⅱ, followed by Type Ⅰ.

An Upper Devonian Kadzielnia-type carbonate buildup in Skrzelczyce Quarry, southern Holy Cross Mountains (Poland)

In Skrzelczyce Quarry, located in the southern part of the Holy Cross Mountains in central Poland, a large Upper Devonian carbonate mound is exposed. The Skrzelczyce mound, developed as massive and faintly bedded limestones, measures nearly 100 m in lateral extent and over 20 m in thickness, and laterally passes into coral-rich biostromal limestones belonging to the Sitkówka Beds. Four facies have been identified within the massive limestone unit: stromatactis-bearing limestones with scarce macrofossils (M1), macrofossil-rich limestones (M2), stromatoporoid-microbial limestones (M3), and limestones with fenestral structures (M4). These facies indicate varying depositional conditions and microbial activity, reflecting a complex interplay of environmental factors. The mound’s lithological features and spatial facies distribution resemble the late development stage of Devonian atolls in the Ardennes. This analogy suggests that the initial mound setting at Skrzelczyce might have been at depths of 30–60 m, in a moderate energy zone. The mound, composed predominantly of polygenetic biomicrite with a significant presence of laminar stromatoporoids and corals, features various forms of stromatactis, some typical and others related to sediment winnowing or to shelter cavities. The foraminiferal assemblages, along with lithostratigraphic correlation, suggest that the Skrzelczyce mound may belong to the lower to middle Frasnian, although the precise age remains uncertain due to the lack of conodont dating. The Skrzelczyce mound aligns with the definition of the Kadzielnia Member, and particular facies from Skrzelczyce can be matched with those described from the Kadzielnia Quarry. The structure outcropping in Skrzelczyce is the second largest Upper Devonian carbonate buildup after Kadzielnia in the Holy Cross Mountains, and the largest on the southern edge of the Kielce carbonate platform.