Search

Theodor Posewitz (1850–1917), a Hungarian medical doctor and geologist, spent five years in the Dutch East Indies between 1880 and 1885, serving the colonial Dutch army. He spent time on Java, Borneo, Bangka and Billiton islands. He dedicated his spare time to geological exploration. About eighty of his geological studies appeared in geological and geographical journals. His chief work, the first monograph on the geology of Borneo, including geological and mineral resources maps, was published in German in 1889 and in English in 1892. Early years of his studies and the results of his five-year stay in Asia are discussed, based on archival records. The background for the book, Borneo, and its significance for contemporary and modern science is outlined. [ABSTRACT FROM AUTHOR]

Geophysical methods of rock mass survey are one of the most effective ways of solving various problems in mining and are widely used in mining, gas and oil industries, as well as in science. They allow carrying out prospecting and evaluation works remotely, to reveal structural heterogeneities, cavities, contact zones of different media in rock mass with rather high accuracy. At the stage of designing a mining enterprise and making major decisions, it is necessary to have reliable information about the tectonic structure of the undermined and adjacent massif and parameters of its geodynamic activity. For this purpose, special studies of the tectonic structure of the rock massif must be carried out and the parameters of modern geodynamic movements must be determined. The most complete information about tectonic disturbances, identification of gliding surfaces, zones of macrofracturing are provided by geophysical methods of rock mass survey.In the article analysis of study of structural-tectonic structure of ore areas, separation and specification of ore-controlling structures, detection and depth mapping of ore-controlling faults, volume mapping of intrusive massifs based on previously conducted geophysical research in Zhezkazgan syncline area carried out. Geological and geophysical conditions of the central ore field (presence of rich bodies with high electric conductivity, considerable thicknesses of ore bodies, etc.) were favorable for application of various geophysical methods to search and trace rich ore bodies occurring at low depths.Moreover, possibilities of application of seismic works are considered at the solution of problems of ore geology in difficult mining-geological conditions of Kazakhstan. [ABSTRACT FROM AUTHOR]

A blanket of sedimentary and regolith material covers approximately three-quarters of the Australian continent, obscuring the crustal geology below and potential mineral resources within. Sedimentary basins also trap seismic energy increasing seismic hazard and generating noisy seismograms that make determining deeper crustal and lithospheric structure more challenging. The most fundamental question that can first be asked in addressing these challenges is how thick are the sediments? Borehole drilling and active seismic experiments using a controlled seismic source (e.g. vibroseis) provide excellent constraints, but they are limited in geographical coverage due to their expense, especially when operating in remote areas. On the other hand, passive-seismic experiments that involve the deployment of seismic receivers only (i.e. seismometers) are relatively low-cost and portable, providing a practical alternative for initial surveys. Here we utilize receiver functions obtained for both temporary and permanent seismic stations in South Australia, covering regions with a diverse sediment distribution. We present a straightforward method to determine the basement depth based on the arrival time of the P -converted-to- S phase generated at the boundary between the crustal basement and sedimentary strata above. Utilizing the available borehole data, we establish a simple predictive relationship between Ps arrival time and the basement depth, which could then be applied to other sedimentary basins with some consideration. The method is found to work best for Phanerozoic sediments and offers a way to determine the sediment–basement interface in unexplored areas requiring only temporary seismic stations deployed for < 6 months. [ABSTRACT FROM AUTHOR]

A roof fall hazard is still one of the major threats in the underground mining industry. Each such type of event always brings great risk to miners and causes serious interruptions in the process of rock excavation. In general, the possibility of roof fall hazard occurrence is directly related to the local geology, the presence of horizontal stresses as well as the type of excavation method and the efficacy of the utilized roof support. Due to the complexity of this process, it is important to continuously evaluate the roof fall risk, especially in long life-time places where a mining crew is often present. Within this article, a detailed review of the current methods of monitoring and evaluating roof fall risk was presented. Based on the extensive literature survey, different types of devices were described, and their advantages and disadvantages were pointed out. Furthermore, new trends in the area of roof fall risk monitoring were described and discussed. [ABSTRACT FROM AUTHOR]

Every day, mining corporations grow and develop over Egypt's Eastern Desert in search of gold, silver, and other metals. Mineral resources in Egypt are a powerful tool for increasing national income. In this study, we are interested in mineral exploration, such as gold and porphyry deposits, using aeromagnetic data, applying various processing techniques such as First Vertical Derivative, Total Horizontal Gradient, Analytical Signal, Tilt Derivative, and the center of exploration targeting (CET). The study area is located at the Central Eastern Desert, which includes the Barramiya, Abu Marwa, and Abu Mireiwah regions. The analysis of the delineated structural trends shows that the N–S, NW–SE, and NE–SW are the most effective directions for managing deposits in the investigated area. A minor trend is also shown in the E–W direction and corresponds to the alteration zones reported by geology and prior investigations. Mineralization zones occur most frequently at the contact between ophiolitic serpentinite, sediments, and other rock types. This study intends to add more about the use of the recently developed technology of CET grid analysis for mineral exploration and structural interpretation across the Central Eastern Desert. The CET porphyry analysis map shows locations where several occurrences of porphyry deposits are probable. The newly discovered spots are similar to the area's usual deposit sites. This study proves that aeromagnetic data are significant in mineral exploration since they are useful for the discovery of the structure and shear zones controlling the mineralization zones. [ABSTRACT FROM AUTHOR]

Background: Mining can directly and indirectly affect social and environmental systems in a range of positive and negative ways, and may result in societal benefits, but may also cause conflicts, not least in relation to land use. Mining always affects the environment, whilst remediation and mitigation efforts may effectively ameliorate some negative environmental impacts. Social and environmental systems in Arctic and boreal regions are particularly sensitive to impacts from development for numerous reasons, not least of which are the reliance of Indigenous peoples on subsistence livelihoods and long recovery times of fragile ecosystems. With growing metal demand, mining in the Arctic is expected to increase, demanding a better understand its social and environmental impacts. We report here the results of a systematic mapping of research evidence of the impacts of metal mining in Arctic and boreal regions. Methods: We searched multiple bibliographic databases and organisational websites for relevant research using tested search strategies. We also collected evidence from stakeholders and rightsholders identified in the wider 3MK project (Mapping the impacts of Mining using Multiple Knowledges, https://osf.io/cvh3u). We screened articles at three stages (title, abstract, and full text) according to a predetermined set of inclusion criteria, with consistency checks between reviewers at each level. We extracted data relating to causal linkages between actions or impacts and measured outcomes, along with descriptive information about the articles and studies. We have produced an interactive database along with interactive visualisations, and identify knowledge gaps and clusters using heat maps. Review findings: Searches identified over 32,000 potentially relevant records, which resulted in a total of 585 articles being retained in the systematic map. This corresponded to 902 lines of data on impact or mitigation pathways. The evidence was relatively evenly spread across topics, but there was a bias towards research in Canada (35% of the evidence base). Research was focused on copper (23%), gold (18%), and zinc (16%) extraction as the top three minerals, and open pit mines were most commonly studied (33%). Research most commonly focused on operation stages, followed by abandonment and post-closure, with little evidence on early stages (prospecting, exploration, construction; 2%), expansion (0.2%), or decommissioning/closure (0.3%). Mitigation measures were not frequently studied (18% articles), with groundwater mitigation most frequently investigated (54% of mitigations), followed by soil quality (12%) and flora species groups (10%). Control-impact study designs were most common (68%) with reference sites as the most frequently used comparator (43%). Only 7 articles investigated social and environmental outcomes together. the most commonly reported system was biodiversity (39%), followed by water (34%), societies (20%), and soil/geology (6%), with air the least common (1%). Conclusions: The evidence found highlights a suite of potential knowledge gaps, namely: on early stages prior to operation; effectiveness of mitigation measures; stronger causal inference study designs; migration and demography; cumulative impacts; and impacts on local and Indigenous communities. We also tentatively suggest subtopics where the number of studies could allow systematic reviews: operation, post-closure, and abandonment stages; individual faunal species, surface water quality, water sediment quality; and, groundwater mitigation measure effectiveness. [ABSTRACT FROM AUTHOR]

Magmatic processes that emerged with the evolution of the Neotethys ocean and associated lithospheric plates caused the formation of significant mineralization in the Tethys belt. The Eastern Pontides, which are located in the northeast of Türkiye and are a part of the Tethys metallogenic belt, are particularly rich in porphyry-type mineralization and represent an important region for Cu-Mo exploration. A large number of Cu, Pb and Zn anomalies have been determined in a large region including the Güzelyayla Cu-Mo field by stream sediment sampling. The Güzelyayla occurrence is Cu-Mo mineralization associated with andesitic/basaltic volcanic rocks and intrusive dacites crosscutting these rocks. The Güzelyayla Cu-Mo mineralization developed in the stockwork and fault-controlled silicified zones. Homogenization temperature values vary between 324 °C and 420 °C (average 374 °C). Salinity values range between 2.2 and 18.6% NaCl (average 9.1% NaCl). A concentric alteration zoning surrounding the potassic alteration indicates a gradual change in the physicochemical properties of the solutions forming the mineralization. The Güzelyayla mineralization was formed in the Eocene (50.7 ± 1.0 million years) period in the Upper Cretaceous volcanic rocks in relation to post-collisional processes in the magmatic arc environment. Contrary to previous studies, estimation zone models were created and an estimated 54.2 million tons of extracted/potential mineral resource with an average grade of 0.20% Cu and 0.014% Mo (0.26% Cu equivalent grade) was made in the Güzelyayla field. [ABSTRACT FROM AUTHOR]

Over the last two decades, Mineral Resources Tasmania has been developing regional 3D geological and geophysical models for prospective terranes at a range of scales and extents as part of its suite of precompetitive geoscience products. These have evolved in conjunction with developments in 3D modeling technology over that time. Commencing with a jurisdiction-wide 3D model in 2002, subsequent modeling projects have explored a range of approaches to the development of 3D models as a vehicle for the better synthesis and understanding of controls on ore-forming processes and prospectivity. These models are built on high-quality potential field data sets. Assignment of bulk properties derived from previous well-constrained geophysical modeling and an extensive rock property database has enabled the identification of anomalous features that have been targeted for follow-up mineral exploration. An aspect of this effort has been the generation of uncertainty estimates for model features. Our experience is that this process can be hindered by models that are too large or too detailed to be interrogated easily, especially when modeling techniques do not readily permit significant geometric changes. The most effective 3D modeling workflow for insights into mineral exploration is that which facilitates the rapid hypothesis testing of a wide range of scenarios whilst satisfying the constraints of observed data. [ABSTRACT FROM AUTHOR]