Bulletin of the Mineral Research and Exploration (BMRE)
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Investigation of the relationship between Remote Sensing and Ground Observations in the detection of hematite minerals in Vera Rubin Ridge, Mars
No full textThe sensors on landers and rovers on Mars enable the performance of highly sensitive analyses in a limited area. However, orbiting satellites can observe the entire surface of Mars, albeit with coarser results than those obtained by landers and rovers. The objective of the study was to calibrate the distribution of hematite (Fe2O3) minerals derived from satellite data using ground observations, thereby producing more sensitive data across a larger area of the Vera Rubin Ridge (VRR) region. This topographic elevation extends from the northeast to the southwest in the northwest region of the Gale Crater. In the study, a model was established between the CRISM instrument data on the MRO satellite and the Mastcam sensor data on the Curiosity rover to determine the corrections that should be applied to the satellite data. The BD860_2 parameter, which identifies the hematite mineral, was adjusted to ModBD860_2 by employing the model’s regression coefficients, which exhibited a Pearson correlation coefficient (r) of 66% and a mean absolute error (MAE) of 2.1%. By applying the ModBD860_2 indice to the CRISM data, it was concluded that areas where the BD860_2 indice did not detect the presence of hematite could also be potential exploration areas
A contribution to the formation of the Karadut Iron Deposit (Kahramanmaraş-Göksun) and its surrounding mineralizations with new findings
No full textKaradut iron mineralization, situated between the Göksun and Elbistan districts in the Eastern Taurus. Many large and small iron deposits and mineralization are distributed across a 40-kilometer region south of the Sürgü fault. These mineralizations are notable not only for their high-grade ore but also for how they are formed. This study aims to investigate these mineralizations by analyzing their mineralogical characteristics and examining their spatial and temporal relationships with host rocks through field observations. Karadut iron mineralization comprises two primary types: metamorphic banded magnetite and hydrothermal hematite-goethite. Metamorphic banded mineralizations, observed as numerous deposits, offer small-scale reserves. Magnetites are aligned parallel to the lamination within micaschists, with thicknesses ranging from 1 cm to 10 m. Near-surface magnetites exhibit hematite formation via martitization, accompanied by supergene limonite formations. Analyses of outcrop and core samples reveal iron contents ranging from 34.20% to 85.14% Fe2O3. This study provides the first detailed exploration of hydrothermal-type mineralizations in high-altitude areas with limited accessibility. Mineralization developed along karstic voids and tectonic lines, primarily consisting of hematite and goethite, with barite as a gangue mineral. Outcrop samples indicate iron contents reaching 85.6% Fe2O3
Geochemical and geophysical relationship of the potassium-rich fenite zone in surface and subsurface investigations of the giant Kuluncak (Malatya) Nb-U-REE-Zr-Li mineralization
No full textThe Kuluncak (Malatya) district hosts one of the most significant Nb–U–REE–Zr–Li mineralizations in Türkiye, spatially associated with alkaline and carbonatite-related rocks. In this study, geochemical and geophysical investigations were integrated with surface and drillhole data to evaluate the role of fenitization in rare earth element enrichment. The drillhole profiles reveal systematic variations: in marble-hosted sections, light rare earth element (LREE) anomalies occur near-surface zones coupled with K2O enrichment, whereas in nepheline syenite-hosted drillholes, REE anomalies are concentrated at intermediate depths (~40–100 m) with heterogeneous distributions. High CaO concentrations, together with fluorite, barite, apatite, and Nb–REE-bearing minerals, confirm a strong carbonatitic contribution. Geophysical anomalies (spectral gamma, magnetic maps) support the geochemical evidence and were used to identify subsurface fenite zones. Comparison with other carbonatite-related systems in Türkiye, such as the Özvatan complex (Kayseri) and Eskişehir, indicates that Kuluncak represents one of the most carbonatite-dominant and LREE-enriched systems in the region. On a global scale, the geochemical features of Kuluncak resemble world-class deposits such as Bayan Obo (China) and Ilímaussaq (Greenland). These findings demonstrate that fenitization and carbonatite-related metasomatism are the principal processes controlling mineralization, highlighting the Kuluncak district as a strategic Nb–REE resource of both national and international importance
Assessment of active tectonics based on GIS and statistical model: A case study of upper Alaknanda catchment (western Himalaya, India)
No full textDue to continuing deformation of the Earth’s crust, degradation and aggradation processes, the upper part of the Alaknanda basin lying in the Garhwal Himalaya, India, is considered to be tectonically active. Active tectonics in this region made a considerable impact on the drainage system and the topographic expression. Using a digital elevation model (DEM) with a resolution of 30 m * 30 m and based on eight geomorphic indices [hypsometric integral (HI), drainage texture (Dt), asymmetry factor (AF), ruggedness number (Rd), valley floor width/height ratio (Vfw), lemniscate coefficient (k) and basin shape index (Bs)], we evaluated active tectonics. Application of Index of Active Tectonic (IAT) and clustering model disclose the sub-watersheds in the southern part covering watersheds 16, 17 and near Badrinath sub-watershed 4, 9 and 8 are tectonically highly active (Class-1, 1.500-1.781). Cluster analysis defines two prominent clusters of sub-watersheds: 2, 4,14 and 15 in cluster 1; and 6, 7, 8 and 18 in cluster 2. Cluster 1 includes sub-watersheds 2, 4, 14, 15, and 16 and very high, high, and moderate IAT magnitudes. Sub-watersheds 6, 7, 8, and 18 are included in Cluster 2, which has very high and high tectonic activity
Choosing the composition of a drilling fluid containing partially hydrolyzed polyacrylamides (PHPA) for core drillings
No full textIn core (diamond) drilling operations, the controlling of drilling fluid’s rheological and filtration properties within specific value ranges is essential to ensure effective well cleaning and the maintenance of both mechanical and chemical equilibrium within the well. Furthermore, the additives in the fluid contribute significantly to improving core recovery efficiency. Partially hydrolyzed polyacrylamides (PHPA), known for their ability to encapsulate formations and drill cuttings to prevent the interaction of active clays with water, are also recognized for their effectiveness in improving core recovery efficiency. In core drilling operations, the high-speed rotation of the drill string can lead to challenges such as cake formation when the drilling fluid contains excessive solid particles (e.g., bentonite, calcite, barite, or drill cuttings). Drilling fluid engineers typically prefer polymer-based fluids with low solids content to reduce these issues. In this study, the rheological and filtration properties of various low-solids fluid compositions containing PHPA were investigated under laboratory conditions to identify the most suitable formulations for core drilling. The results of tests revealed that fluid compositions incorporating calcite + xanthan gum + modified starch + PHPA and bentonite + xanthan gum + modified starch + PHPA exhibited superior rheological and filtration properties compared to other fluid formulations. Additionally, the composition of PAC L + PHPA + calcium carbonate exhibited rheological and filtration values suitable for core drilling applications
The Uzunpınar (Boztepe-Kırşehir) Zn-Pb±Cu mineralization: A metamorphosed SEDEX-type mineralization in the Kırşehir Massif
No full textThe Uzunpınar (Boztepe-Kırşehir) Zn-Pb±Cu mineralization is hosted within the gneiss and marbles of Paleozoic Kalkanlıdağ Formation of the Central Anatolian Crystalline Complex. The rocks observed in the mineralization area are mica gneiss, marble, migmatite, and microgranite, which were formed through high-grade metamorphism and anatexis of pelitic and carbonate protoliths. The mineralization has a stratiform geometry which extends approximately 1,850 m in a NE-SW direction. Six distinct mineralization levels (horizons), exhibiting similar characteristics and thicknesses ranging from 3.1–32.10 m, have been identified hosted within gneisses and marbles. These levels comprise ore bands and disseminations with thicknesses of 0.1–8 cm, aligned parallel to the foliation. Ore minerals are sphalerite, galena, chalcopyrite, and minor scheelite, while gangue minerals are pyrite, marcasite, pyrrhotite, gahnite, and Bafeldspar. In the Uzunpınar mineralization, the alignment of ore bands with the host rock foliation, the presence of coarse-grained euhedral opaque minerals, foam textures, gahnite, Ba-feldspar, and the high Fe content in sphalerites serve as evidence for the influence of metamorphism on the mineralization. The stratiform geometry, syngenetic origin, and metal and mineral paragenesis suggest a SEDEX origin for the mineralization, later metamorphosed together with its host rocks
Effect of calculated dry rock bulk modulus on uncertainty in compressional wave velocities derived from Gassmann fluid substitution theory and fluid mixing law in a CO2 sequestration case
No full textThis study examines the effect of variations in dry rock bulk modulus (Kdry) on compressional wave velocity (Vp) using Gassmann fluid substitution theory and various fluid mixing laws in the context of CO2 sequestration in the Utsira formation at the Sleipner Field. Significant changes in Vp, exceeding 600 m/s, were observed, particularly when applying the Gassmann-Wood law, which demonstrated heightened sensitivity to saturation variations. In contrast, the Gassmann-Brie approach, utilizing an empirically selected constant, produced more stable and reliable results. This study emphasizes that relying solely on the Gassmann-Wood equation for Kdry calculations may result in inaccurate predictions, particularly for CO2-saturated formations. To mitigate this, laboratory measurements of Kdry are recommended to enhance the reliability of predictions. Furthermore, initial saturation conditions critically affect the Vp calculations, underlining the importance of selecting an appropriate mixing law to ensure accurate assessments during CO2 injection and storage
Establishing of soil loss tolerance limit and sediment yield in Zagros fold-thrust belt: a case study in the Kanarwe river basin, Iraq-Iran
No full textSoil degradation is a significant cause of topsoil loss; in most mountainous region watersheds, it leads to decreased agriculture productivity and reservoir storage. This study targeted calculating and mapping soil loss and sediment yield in the Lesser Zab watershed located between Iraq and Iran. The Revised Universal Soil Loss Equation (RUSLE) model was used to calculate the soil loss. A Digital Elevation Model of 30m, a Digital Soil map (1:500000), rainfall, and land cover were used to derive parameters. The soil loss rates are 58.1 and 0.1 tha-1yr-1. The total annual soil loss is 1037289 tonnes, of these 404512, covering 75% of Kanarwe river basin land. Most of these affected lands are in the eastern and middle part, which is below the FAOs standard allowable for tolerable soil erosion. Still, the rest covers 25 % of the basin in the west with a total annual soil loss equal to 632777 tonnes, above FAOs standard. The maximum and minimum sediment yield is 29 and 0.1 tha-1yr-1, respectively. Based on the statistical correlation coefficient, the most effective RUSLE parameters on sediment yield from high to low are topography 0.48, soil erodibility 0.38, and crop management 0.38
Sediment thickness in the Thrace Basin estimated from the three-dimensional inversion of magnetotelluric data
No full textThe time-variation of the magnetotelluric (MT) fields was recorded at 37 measurement stations in the Thrace Basin (North-western Türkiye) by a remote-reference MT system that records the MT data in two frequency bands allowing a data acquisition between 320–7.5 Hz and 6–0.00055 Hz, respectively. The measurement stations were located from the Aegean Sea to the Black Sea seashores along a 207 km profile in the southeast-northwest direction. Three-dimensional inversion of MT data outlined the main geological elements of the region, the interface between sedimentary cover and basement rocks. The total thickness of the sedimentary layers in the basin is interpreted using the inflection and deflection points of the three-dimensional resistivity model in the vertical direction
Discussion: Determination of Atterberg Limits Using the Vane Shear Test Method [Bull. Min. Res. Exp. (2024) 174: 1–10]
No full textThis article presents a discussion of the original research reported in the paper by Kayabalı et al. (2024) (the Authors) that was recently published in the Bulletin of the Mineral Research and Exploration Vol. 174, pp. 1–10. Using liquid limit (LL), plastic limit (PL) and vane shear strength against water content [i.e., su(VST)–w] results obtained for 100 fine-grained soil samples, the Authors performed multiple regression analyses to produce four strength-based correlations for predicting the LL and PL values based on su(VST)–w measurements. The Authors’ dataset primarily consisted of residual soils formed through the weathering of igneous rocks, along with a few lacustrine soil samples, all sourced from the vicinity of Ankara, Türkiye. This discussion article examines the veracity of the Authors’ claims regarding the predictive performance of their proposed correlations when applied to other fine-grained soils. Using a sizable independent database of dissimilar fine-grained soils compiled from the research literature, it is conclusively shown that, contrary to the Authors’ assertions, their proposed correlations generally produce poor LL and PL predictions when employed beyond the calibration soil types. This outcome is not unexpected, since the Authors’ data-driven correlations were deduced based on a specific dataset with limited diversity in terms of soil physico-chemical and mineralogical attributes. The article closes with a discussion of the plausible explanations for the poor applicability of the Authors’ correlations when apllied to dissimilar fine-grained soils