Early Cambrian rhyolite hosts the Choghart iron oxide-apatite (IOA) deposit. The ground radiometric and spectrometric surveys of alteration zone on the margin of the magnetite-apatite ore body show that the radioactive anomaly of Thorium occurs in the breccia zone. The chemical analyses of the breccia zone samples by ICP– MS show Thorium mineralization. The mineralogical studies by transmitted-and reflected-light microscopey and EPMA indicate that the main Thorium minerals in Thorium mineralization zone are thorite and sphene. The alteration mineral assemblages related to Thorium mineralization of Choghart is consisted of albite ± orthoclase + calc-silicate (actinolite-augite-diopside) + carbonate (calcite) + magnetite + pyrite ± chalcopyrite ± galena + sphene + rutile ± microcline ± apatite (Na-Ca-Fe alteration). The occurrence of paragentic magnetite, pyrite and chalcopyrite with thorite and negative Eu anomaly in the Thorium mineralization zone indicate a reduced condition for Thorium mineralizing fluids. The similarity in chondrite-and mantle-normalized REE patterns of host rhyolite and the Thorium mineralization zone suggests that Thorium is originated from continental-arc rhyolitic magma.

The Chahgaz iron deposit (XIV Anomaly) is located in the Bafq mining district in the Central Iranian geostructural zone in Yazd province. The Chahgaz deposit is hosted by Early Cambrian subvolcanic and volcanic rocks that range compositionally from granite to diorite. The field gamma spectrometry, mineralogical and geochemical studies in this deposit indicate that the Thorium mineralization is mainly associated with Na-Ca and Mg-alterations, and in minor amount with the magnetite ore. The mineralogical studies by optical and electron microscope (SEM and EPMA) indicate that the main Thorium host mineral in the Chahgaz deposit is thorite associated with minor titanite, allanite and zircon. The average contents of Th and Σ, REE in the Th-mineralization zone are 450 and 596 ppm, respectively. Thorite is paragenesis with albite, actinolite, tremolite and augite in the Na-Ca alteration zone, and with talc in the Mg-alteration zone. In the Th-bearing iron ore, thorite is paragenesis with magnetite, calcite and apatite mineral assemblage. The similarity in mantle-normalized REE patterns of host rocks and Thorium mineralization zone suggests that Th-mineralization is related to Early Cambrian calc-alkaline magmatism in continental-margin arc setting. The occurrence of paragenetic magnetite with thorite and distinct negative Eu anomaly in the Thorium mineralization zone can be inferred probably a reduced condition for Thorium mineralizing fluids.

This research investigates and optimizes the parameters of solvent extraction processes using Thorium leach solutions from Chahgaz ore with D2EHPA. The effective parameters in the solvent extraction process were evaluated through experimental design to maximize Thorium extraction and minimize iron extraction. Under optimum conditions—pH 0.6, extraction time of 2 minutes, 16% solvent concentration, and an organic-to-aqueous phase ratio of 1:2—Thorium and iron recoveries were 99.47% and 9.60%, respectively. For the optimization of the stripping process, 89.75% Thorium and 0.6% iron were recovered in 3.34 minutes with an organic-to-aqueous phase ratio of 2:1 and a sulfuric acid concentration of 3.9M.

The Chapdoni-Posht-e-Badam complex is located in the Central Iranian structural zone and the northeast of Yazd province. This complex is one of the areas with high potential for Thorium-rare earth elements mineralization in Central Iran. In this research, the network modeling method has been used to determine the type and potential of Th-REE mineralization in the study area. Different methods such as geochemistry, geophysics, remote sensing, field observations, and laboratory works have been used, and different criteria have been considered for scoring. After applying the mentioned methods, creating a database, and combining multiple layers, the mineralization model or possible deposit types have been determined. This research uses a network method to integrate different data layers and model them to produce a mineralization potential map. The results obtained for different types of mineralization models were combined in the form of final modeling, and a comprehensive map of mineralization potential was prepared. Finally, mineralization types related to granite, metasomatism, and metamorphism were determined for Thorium and rare earth elements in the Chapdoni-Posht-e-Badam complex. The mineralization potential of Thorium-rare earth elements in the center and south of the study area is more than in other places.

The studied area in the Saghand fifth anomaly is located in the Bafgh-Posht-e-Badam metalogeny belt in the Central Iran zone. Uranium, Thorium and Rare Earth Elements mineralization are hydrothermal and metasomatism type related to area intrusion bodies (Granite and Gabbro available in the north of study area). Uranium of hydrothermal type followed by deep fracture systems and concentrated around the magnetite bodies. The reasons are geochemical environment and alkaline metasomatism of Uranium - Thorium and Rare Earth Elements produced under an important metalogeny cycle in the Central Iran and studied area. The tudied area in special case, Cerium and Yttrium show positive correlation with mineralization of radioactive materials (Uranium – Thorium). Considering the genetic relationship between these elements (Cerium and Yttrium), popular separation of anomalous elements carried out by using classical statistical methods for lithogeochemical data and calculated statistical parameters. Then, the frequency distribution histograms along the calculation were plotted and consequently, the separation of anomalous element populations carried out. High positive correlation among the radioactive elements (U & Th) and Rare Earth Elements such as Cerium and Yttrium indicated that their mineralization phase generated from the same origin. Compilation of geochemical and geological rock unit maps designated that the radioactive ore mineralization was controlled by metasomatism, which produced different types of albite metasomatite, amphibole metasomatite, and albite-amphibole metasomatite from the rocks of pyroclastics, diabase, dacite and gabbro in the area. Uranium and Thorium anomalies calculated by classical statistical methods are mostly distributed in the west, southwest, and central part of the area, but in the central part the Th-intensity relatively was stronger than the Uranium. The anomaly trend for Cerium and Yttrium are the same as the Uranium and Thorium, but Yttrium anomaly in the central part is more intensive than the others.

This paper deals a with the study of an innovative method for processing the Oman placer ores by alkaline leaching in ball mill autoclaves, where grinding and leaching of the refractory minerals take place simultaneously. This was followed by the selective separation of Thorium and uranium from lanthanides by autoclave leaching of the hydroxide cake with ammonium carbonate-bicarbonate solutions. The introduced method is based on the fact that Thorium and uranium form soluble carbonate complexes with ammonium carbonate, while lanthanides form sparingly soluble double carbonates. It was found that a complete alkaline leaching of Oman placer ores (98.0%) was attained at 150 and 175oC within 2.5 and 2h, respectively. Oman placer ores leaching was intensified and accelerated in a ball mill autoclaves as a result of the grinding action of steel balls, removal of the hydroxide layer covering ores grains and the continuous contact of fresh ore grains with alkaline solution. The study of selective carbonate processing of hydroxide cake with ammonium carbonate-bicarbonate solutions on autoclave under pressure revealed that the complete Thorium recovery (97.5%) with uranium recovery (90.8%) and their separation from the lanthanides were attained at 70-80oC during 1-2h. The extraction of lanthanides in carbonate solution was low and did not exceed 4.6%.

Thorium is a radioactive metal and is actinide family of periodic table with a half-life of 14 billion years and approximately 99% is in the form of Thorium-232 isotopes. From past to present it has been used as a contrast agent (in the form of thorotrast) in imaging, ceramic manufacturing, applications in aerospace industries and it is now considered a contributing element to the fuel cycle in nuclear facilities of some countries. Thorium emits alpha, beta and gamma rays. Therefor it is necessary to know the health implications and understand the consequences of exposure to this radioactive substance. Due to differences in the routes of entry of Thorium into the body example of inhalation, mouth and skin, absorption and distribution and its effects on human and animals body are different. In this paper which begins with the introduction of Thorium properties, after examining the pathways of its entry into the body, examples of its consequences for human, animals and the environment are discussed.

The available radioactive elements in the nature, in themselves decay series to other elements, emit alpha, beta and gamma rays that attention to power of penetration of gamma ray is used from this gamma ray measurements, for radiometric exploration of radiometric element specific for uranium. With use taken data of airborne radiometric simply can be studied a large area in a short time and with a little cost. Attention to distribution of Uranium element in the earth crust and study of these maps, the main parts of first stage of Uranium exploration are the factors and methods of separation of boundaries and hot points of anomaly from background parts. The maps of anomaly introduction and mine index of Uranium and tourium are prepared to continue the exploration work in Zahedan area.

This study was set out to delineate prospective zones of gold mineralization occurrence over the Julie tenement of Northwestern Ghana using two spatial statistical techniques, namely information value (IV) and weight of evidence (WofE) models. First, 110 locations, where gold (Au) mineralization has been observed, were identified by field survey results derived from highly anomalous geo-chemical assay datasets. Of these 110 locations, 77 (representing 70% of the known locations, where gold has been observed) were randomly selected for training the aforementioned models, and the remaining 33 (analogous to 30% of the known Au occurrence) were used for validation. Secondly, eleven mineral conditioning factors (evidential layers) comprising analytic signal, reduction-to-equator (RTE), lineament density (LD), porphyry density, potassium concentration, Thorium concentration, uranium concentration, potassium-Thorium ratio, uranium-Thorium ratio, geology, and arsenic concentration layers were sourced from geo-physical, geological, and geo-chemical datasets. Subsequently, by synthesizing these eleven evidential layers using the two spatial statistical techniques, two mineral prospectivity models were created in a geographic information system (GIS) environment. Finally, the mineral prospectivity models produced were validated using the area under the receiver operating characteristics curve (AUC). The results obtained showed that the IV model produced had a higher prediction accuracy in comparison with the mineral predictive model produced by the WofE with their AUC scores being 0.751 and 0.743, respectively.