Integrating Core and Aeromagnetic Datasets to Evaluate Mineral Potential of Southern Nupe Basin, Nigeria

Aeromagnetic and core drilled data covering parts of southern Nupe Basin was acquired and interpreted with the view to evaluating the mineral potentials of the area through interpretation of the structural features in the area; determination of the curie isotherm depth; and correlation of aeromagnetic outcomes with the core sample data from the area. Two major regional fault trends were interpreted, trending, Northeast–Southwest (NE–SW) and NNE–SSW with minor northwest–southeast (NW–SE) directions. Two depth sources in the area are delineated namely; zone of shallow seated basement which ranges from 0.42km to 1.5km and zone of deeply seated basement which ranges from 1.91 to 3.50km.Results of qualitative interpretation of the Total magnetic intensity map (TMI) and Residual intensity map reveal that the magnetic intensities ranges from 7500 to 8460 nano-Telsa (nT) and -220 to 240 nT respectively. The depth to the centroid and top of the magnetic caustic bodies ranges from 9.00 to 17.10km and 0.4 to 3.10km respectively. Juxtaposing the topographical and core drilling data reveals that the oolitic iron ore level follows the topographical level which implies that the topography of the area controls the configuration of the iron ore deposit level. All these deduction are made considering the geology of the area.

Genesis and structure of the iron ore deposit of the Cape Iron Horn

Статья посвящена железорудному месторождению, представляющему собой пласт оолитовых (бурожелезняковых) руд железа, который выходит на дневную поверхность на мысе Железный Рог на берегу Таманского полуострова. Мыс имеет протяженность 1,3 км с запада на восток и высоту 55 м над уровнем моря. Склон мыса разбит многочисленными трещинами из-за эрозионного воздействия ветра и морской воды, по которым происходит откалывание оползневых тел. Актуальность работы. Железорудное месторождение на мысе Железный Рог Таманского полуострова известно с конца 19 века, в настоящее время (с 1984 года) ему присвоен статус памятника природы, из-за чего добыча сырья запрещена на всей охраняемой территории, составляющей 19 га. Однако минералогия, палеонтология и особенности геологии данного месторождения изучены недостаточно. Таким образом, представленная статья призвана в какой-то степени восполнить этот пробел. Целью проведенных исследований является выявление особенностей геологического строения, минерагении и генезиса железорудного месторождения на мысе Железный Рог Таманского полуострова. Методы работы. Основу работы составляют образцы, отобранные авторами во время полевых работ на мысе Железный Рог с июня по июль 2021 года. При выполнении работы были описаны 15 образцов, а также идентифицированы палеонтологические находки и определен их примерный возраст. Результаты работ. Установлено, что бурые железняки залегают в толще серых глин железнорогской свиты (N1-2žr) и совпадают с ними по возрасту, что подтверждается палеонтологическими находками. В разрезе были найдены только те минералы, в состав которых входит железо: борнит, вивианит, лимонит, халькопирит. В работе проанализированы структурно-текстурные особенности пласта и вмещающих его пород, а также ассоциации найденных минералов, на основании чего сделаны выводы, что данный пласт железных руд относится к хемогенному осадочному типу месторождений, образованному из коллоидных растворов The article is devoted to an iron ore deposit, which is a layer of oolitic (brown limestone) iron ores, which comes to the surface during the day at Cape Iron Horn on the shore of the Taman Peninsula. The cape has a length of 1.3 km from west to east and a height of 55 m above sea level. The slope of the cape is broken by numerous cracks due to the erosive effects of wind and sea water, along which landslide bodies are chipping away. Relevance.The iron ore deposit at Cape Iron Horn of the Taman Peninsula has been known since the end of the 19th century, currently (since 1984) it has been given the status of a natural monument, which is why the extraction of raw materials is prohibited in the entire protected area of 19 hectares. However, mineralogy, paleontology and features of the geology of this deposit have not been studied enough. Thus, the presented article is intended to fill this gap to some extent. The Aim of the research is to identify the features of the geological structure, mineralogy and genesis of the iron ore deposit at Cape Iron Horn of the Taman Peninsula. Methods. The work is based on samples selected by the authors during field work at Cape Iron Horn from June to July 2021. During the work, 15 samples were described, as well as paleontological finds were identified and their approximate age was determined. Results.It has been established that brown ironstones lie in the thickness of gray clays of the Zheleznogorskaya formation (N1-2žr) and coincide with them in age, which is confirmed by paleontological findings. Only those minerals containing iron were found in the section: bornite, vivianite, limonite, chalcopyrite. The paper analyzes the structural and textural features of the formation and its host rocks, as well as the associations of the minerals found, on the basis of which it is concluded that this iron ore formation belongs to the chemogenic sedimentary type of deposits formed from colloidal solutions

Investigation of Magneto-/Radio-Metric Behavior in Order to Identify an Estimator Model Using K-Means Clustering and Artificial Neural Network (ANN) (Iron Ore Deposit, Yazd, IRAN)

The study area is located near Toot village in the Yazd province of Iran, which is considered in terms of its iron mineralization potential. In this area, due to radioactivity, radiometric surveys were performed in a part of the area where magnetometric studies have also been performed. According to geological studies, the presence of magnetic anomalies can have a complex relationship with the intensity of radioactivity of radioactive elements. Using the K-means clustering method, the centers of the clusters were calculated with and without considering the coordinates of radiometric points. Finally, the behavior of the two variables of magnetic field strength and radioactivity of radioactive elements relative to each other was studied, and a mathematical relationship was presented to analyze the behavior of these two variables relative to each other. On the other hand, the increasing and then decreasing behavior of the intensity of the Earth’s magnetic field relative to the intensity of radioactivity of radioactive elements shows that it is possible to generalize the results of magnetometric surveys to radiometry without radiometric re-sampling in this region and neighboring areas. For this purpose, using the general regression neural network and backpropagation neural network (BPNN) methods, radiometric data were estimated with very good accuracy. The general regression neural network (GRNN) method, with more precision in estimation, was used as a model for estimating the radiation intensity of radioactive elements in other neighboring areas.

Basin Analysis of Tertiary Strata in Golden Bay, Nelson

<p>Eocene to Miocene strata comprise the Brunner Coal Measures (Ak-Ld), Takaka Limestone (Ld-Po), Tarakohe Mudstone (P1-S1) and Waitui Sandstone (Sc-Sl), and form a transgressive-regressive sequence on an essentially stable structural platform. Brunner Coal Measures in the Takaka valley (up to 350m thick) consist of cross-bedded sand and gravel, interlaminated sand and silt, bioturbated muddy sandstone, carbonaceous mudstone and coal. Five facies associations are recognized and interpreted as river/floodbasin, estuarine and shallow marine deposits. In the Aorere and Parapara River catchments, two new members are recognized: the Quartz Wash Member, comprising quartzose sand and conglomerate, and the Washbourn Limonite Member, a sedimentary iron-ore deposit. The Takaka Limestone (up to 100m thick), consists of bryozoan, bivalve or sandy grainstone or packstone, deposited on a tidal current-swept shallow-middle shelf with minimal terrigenous influx. Diagenesis was controlled by pressure-solution during deep burial, and resulted in a rightly cemented rock with dolomite and neomorphic features. The Tarakohe Mudstone (up to 900m thick) is dominated in its lower half by massive mudstone of hemipelagic and turbiditic origin, and in its upper half by shallow shelf-estuarine sandstones and mudstones. The Waitui Sandstone (160m thick) comprises shallow marine sandstone. Deposition of the Brunner Coal Measures took place in localized fault-angle depressions. The Takaka Limestone was deposited during a period of regional subsidence and minimal tectonic activity. The Tarakohe Mudstone and Waitui Sandstone were deposited in synclinal basins which were later modified by rising monoclinal boundaries.</p>

Basin Analysis of Tertiary Strata in Golden Bay, Nelson

<p>Eocene to Miocene strata comprise the Brunner Coal Measures (Ak-Ld), Takaka Limestone (Ld-Po), Tarakohe Mudstone (P1-S1) and Waitui Sandstone (Sc-Sl), and form a transgressive-regressive sequence on an essentially stable structural platform. Brunner Coal Measures in the Takaka valley (up to 350m thick) consist of cross-bedded sand and gravel, interlaminated sand and silt, bioturbated muddy sandstone, carbonaceous mudstone and coal. Five facies associations are recognized and interpreted as river/floodbasin, estuarine and shallow marine deposits. In the Aorere and Parapara River catchments, two new members are recognized: the Quartz Wash Member, comprising quartzose sand and conglomerate, and the Washbourn Limonite Member, a sedimentary iron-ore deposit. The Takaka Limestone (up to 100m thick), consists of bryozoan, bivalve or sandy grainstone or packstone, deposited on a tidal current-swept shallow-middle shelf with minimal terrigenous influx. Diagenesis was controlled by pressure-solution during deep burial, and resulted in a rightly cemented rock with dolomite and neomorphic features. The Tarakohe Mudstone (up to 900m thick) is dominated in its lower half by massive mudstone of hemipelagic and turbiditic origin, and in its upper half by shallow shelf-estuarine sandstones and mudstones. The Waitui Sandstone (160m thick) comprises shallow marine sandstone. Deposition of the Brunner Coal Measures took place in localized fault-angle depressions. The Takaka Limestone was deposited during a period of regional subsidence and minimal tectonic activity. The Tarakohe Mudstone and Waitui Sandstone were deposited in synclinal basins which were later modified by rising monoclinal boundaries.</p>

Ground magnetic survey for the investigation of magnetic minerals at Iboro Village, Abeokuta, south-western Nigeria

The geological map of the old western region of Nigeria indicates the presence of iron ore deposit at Iboro village Ogun state (7.9983o - 7.99933o N, 3.5790o - 3.5890o E). Hence a ground magnetic survey was carried out at a location at Iboro village so as to delineate the subsurface magnetic anomalies and to know whether the anomalies favour accumulation of magnetic minerals. The survey was carried out using high resolution proton precession magnetometer model G-856X. Eight traverses were run at 5m separations and earth magnetic intensity values were measured at 10m intervals along each traverse; the acquired data were corrected for drift. The residual anomalies obtained by removal of regional gradient from observed data using trend analysis were presented as profiles and maps. The treated data were qualitatively and quantitatively interpreted and the results gave values for the total ground magnetic anomalies that varied between a minimum and maximum peak values of about -33.0 and 30.6nT respectively. Depth to the basement rock was estimated using Peter’s half slope method which gave a maximum depth of about 13m. The contour maps and the total relative graphs present the subsurface picture of the geological structure that is assumed to harbour the metallic minerals through the action of the field towards the concentration of anomalies. It was suspected that the overburden was relatively thin in the study area and the minerals were at a shallow depth.

Application of biohydrometallurgical processes for heavy metals removal from acid mine drainage

The main scope of this study was to remediate Acid Mine Drainage (AMD) by application of biohydrometallurgical processes, environmentally friendly, to remove heavy metals such as Zn, Cu, Mn, Cd, Al and Fe. The processes studied have been electrowinning and bioprecipitation. The samples utilised were collected from the zinc mine located in Italy and from a cooper – iron ore deposit in Slovakia. By electrochemical experiments, high metals removal, with a low energetic consumption, has been achieved: in particular, by Zn electrodeposition, it was possible to achieve 95-99% Zn removal. Culture of sulphatereducing bacteria (SRB) of genera Desulfovibrio sp. was used for the bioprecipitation tests. The precipitation kinetic of metals at the original pH of aforementioned AMD by SRB has been investigated. This method has been performed in two interconnected reactors. Achieved results indicate the 98-99% selective elimination of Cd from AMD - Italian mine, and the 98-99% selective elimination of Cu from AMD - Slovak mine by bacterially produced H2S. Both the electrowinning and bioprecipitation processes have been demonstrated the technical feasibility to decrease the heavy metals concentration. The experimental work has been carried out in the framework of the agreement of scientific cooperation between the Institute of Environmental Geology and Geoengineering of the CNR, Italy and the Institute of Geotechnics of Slovak Academy of Sciences, Slovakia (years 2007-2009).

DEVELOPMENT OF INDUCED SEISMICITY IN MINING TASHTAGOL IRON ORE DEPOSIT: RETROSPECTIVE ANALYSIS AND FORECAST

Using the example of the Tashtagol iron ore deposit, an approach has been implemented that makes it possible to reveal the space-time relationships between the parameters of random and deterministic processes of various physical nature, which occur in the rock mass during large-scale mining operations. The approach consists in cross correlation analysis of long time series “number and energy of weak and moderate dynamic events” and “variation of stress field parameters” in different areas of geomechanical space of the object under study. According to the data of automated microseismic control system of the mine (from 1989 to 2019) and calculation results based on the developed 3D model of the deposit, the values of correlation coefficients r between number N of seismic events with an energy of up to 3 kJ and increments of the maximum tangential T and average S stresses in different blocks were determined. The regression dependences N(T) and N(S) constructed for statistically significant r were verified by comparing the predicted and real values of N in 2020. The obtained dependences can be used for geomechanical justification of reserves mining using forward calculations of the stress state and, on this basis, for assessing seismic activity level using the found correlation dependences.