Soil geochemical prospection for gold deposit in the Arzular area (NE Turkey)

摘要

The Arzular gold mineralization is located at the southern part of the Black Sea Tectonic Unit in northern Turkey. This belt hosts several high-potential epithermal gold deposits and it is highly probable that there are a number of undiscovered occurrences in the region. The presence of intensely altered areas, suitable structural elements and acidic intrusions indicates that the region has an important potential for epithermal gold. Soil geochemistry surveys are widely used for the exploration of buried mineral deposits. In this work the applicability of soil geochemistry surveys for exploration of buried mineral deposits was tested using various statistical methods. In this respect, concentrations of 16 elements have been assayed in about 50 soil samples collected from the Arzular area Soil samples were taken from the B horizon. The data revealed elevated concentrations for gold (0.20-259.2 μg/kg), silver (23-26,972 ug/kg), arsenic (1.7-301.8 mg/kg), copper (54.09-170.7 mg/kg), zinc (5.1-2613 mg/kg) and lead (2.6-385.45 mg/kg). Gold is significantly correlated with elements such as Sb, Cd, Pb, Ag, As, Cu and Mo. Relatively high anomaly contrasts between Au, As, Ag and Sb and their coinciding anomalies along an E-W trending fault at the eastern part of the field might indicate that As, Ag and Sb could be used as a pathfinder element for exploration of gold deposits. Factor analysis was applied to elements in soil samples and then distribution diagrams were prepared using the factor scores obtained. In a distribution diagram for mineralization-associated factor score, two anomaly fields along the E-W trending fracture line and one anomaly field at the eastern part were distinguished. The largest anomaly in an ellipsoidal shape with long axis of 350 m was obtained from the southeast part of the area. Anomaly patterns show that factor scores might yield suitable and net results for the exploratioa NE-SW trending fracture system is not related to mineralization and is younger than E-W trending fracture line. However, the E-W trending fault system controls the mineralization; therefore, the eastern extent of this fault zone needs to be investigated.