Evaluation of the alternatives for gold ore grinding circuits by using of laboratory studies results and simulation method; case study: İranian Gold Co.

This study was conducted to determine the effectiveness of three different adsorbents for the adsorption of gold from a real cyanide leach liquor. An activated carbon (NORIT GAC 1240), strong base (Purogold A194), and weak base (Purogold S992) resins were tested as the adsorbents. The pregnant leach solution (PLS) was derived from cyanide leaching (1.5 g/L NaCN, 25% w/w solids ratio, 1.5 L/min air flow rate, pH 10.5 – 11, 24 h) of the roasted copper-rich refractory gold ore pretreated with H2SO4. Gold and copper concentrations in the PLS were analysed to be 26.1 mg/L Au and 62.4 mg/L Cu, respectively. Activated carbon was found to be the best performing adsorbent as it achieved the highest gold loading. Purogold A194 loaded the highest amount of copper amongst the adsorbents tested. Despite the fact that activated carbon loaded a high amount of gold, it was less selective than Purogold S992. Purogold A194 exhibited the lowest selectivity, which was defined as the distribution ratio of gold to copper, compared with Purogold S992 and activated carbon. Therefore, the order of selectivity of the adsorbents tested was as follows: Purogold S992 > Activated carbon > Purogold A194.

Impact breakage functions for a gold ore from Bergama region (Turkey) was estimated based on the single-particle impact breakage distributions of particles obtained from drop weight tests. For this purpose, a modified manual version of a JK Tech drop-weight test device was used. Effect of specific comminution energy (Ecs) on impact breakage distributions were investigated. Relationship between specific comminution energy and impact breakage product fineness (t10) parameter was established. Ecs-t10 model given in the literature was successfully fitted to the breakage test results. Ecs-t10 impact breakage model for the gold ore was proposed to be used in breakage function estimation. t-family curve approach was applied to estimate single particle breakage functions of the gold ore. For this purpose, t-family curves were modelled and variations of empirical breakage functions for the gold ore were estimated on different impact energy levels for comminution process modelling.

Instrumental and historical earthquake catalogues have to be examined and evaluated to understand the long-term seismic behaviour of active faults. Although the instrumental records have been determined from the national and international observatories, the historical seismic catalogues are very limited in Turkey. For the reason, we aimed to compile paleoseismological trench studies carried out before 2012 in the areas of onshore and offshore sections of Turkey. In terms of a Turkey Paleoseismological Project (TURKPAP) posted by General Directorate of Mineral Research and Exploration (MTA) in the 2012 year, a number of paleoseismological investigations have been initiated and documented for archiving at a standardized data layout. In this study, we compiled all paleoseismological trench surveys with the definite dates of past strong seismic events occurred in Turkey before that date. By using this compilation, not only the historical earthquakes but also many paleoseismologic parameters of the studies have been listed clearly. https://doi.org/10.19111/bulletinofmre.561925

The Yenice-Gönen Fault (YGF) is located in the central part of the Biga Peninsula between Gönen and Yenice and is a right-lateral strike-slip active fault with general trending N65°E. On 18 March 1953 there was an earthquake on the YGF that died 263 people (Ms=7.2) and a 70 km surface rupture developed during this earthquake. In this study measurements of slip distribution were performed on the surface rupture of the Yenice-Gönen Earthquake (YGE) and the annual slip rate on the YGF was calculated. Right-lateral displacements of between 1.70±0.1 and 3.20±0.2 metres were measured on the surface rupture of the YGE. The maximum displacements were in an area close to the central part of the YGF (between Çakır and Karaköy village) and these values decreased relatively in NE and SW directions, documenting that was the bilaterally surface rupture propogation during the YGE. In the last 300.000 years, a total offset of 800±50 metres was measured on Gönen River and annual slip rate of 2.65±0.15 mm was calculated along the YGF. Current GPS studies show right-lateral strike-slip faults in the South Marmara region have slip rates of 6-8 mm/year. This slip rate is assessed as being partitioned between the YGF, Sarıköy Fault and Çan-Biga Fault zones which represent extensions of the North Anatolian Fault system within the South Marmara region. Paleoseismology studies determined that in the last 6200 years 6 earthquakes resulting in surface ruptures have occurred on the YGF, including the 1953 earthquake. According to the 14C and OSL dating results, the variable and irregular earthquake recurrence interval of YGF is ranging from 505 to 1793 years. In this study average earthquake recurrence interval of YGF was determined as 1180 years. https://doi.org/10.19111/bulletinofmre.500553

Yarpuz-Kaypak (Osmaniye) region, located in Amanos Mountains, contains harzburgitic tectonites and mafic cumulates. The tectonites are represented by serpantinized harzburgites, whereas the cumulates are characterized by gabbronorite and gabbro compositions. The crystallization order within the cumulates is clinopyroxene, orthopyroxene plagioclase and amphibole. The major element compositions of the tectonites and cumulate rocks are consistent with formation in an arc-related tectonic setting. Trace element concentrations of these rocks exhibit large ion litophile element enrichments. Both geochemical and petrographic evidence suggest that the tectonite and cumulate rocks from the Yarpuz-Kaypak (Osmaniye) region represent the remnants of an oceanic lithosphere that formed in a supra-subduction zone tectonic setting during the closure of the Southern Neotethyan ocean and emplaced onto the northern margin of the Arabian platform in Late Cretaceous. https://doi.org/10.19111/bulletinofmre.501393