Indicators of the hydrothermal mineralization in the Tincova Laramian intrusion were tested at the contact zone between the intrusive body and the metamorphic host rocks. The mineralization consists of Cu, Pb and Zn sulfides, arsenopyrite, pyrrhotite and pyrite in gangue of quartz, carbonates, feldspar, sericite or clay minerals, and includes areas of hydrothermal alteration or oxidation. Seventy-nine samples were analyzed and processed as two distinct populations. Geomathematical methods highlight the importance of factors such as the shape, sizes of the mineralized zones and geological processes involved in the ore genesis. Trend maps for Cu, Pb + Zn, and Ag interpolated by kriging method, show anomalous values of Cu along the edge of the intrusive body with the metamorphic country rocks, and Pb + Zn in a marginal area. Departing from the study of correlations between different variables, the factor analysis (R-mode) highlights five factors that represent a sequence of geological processes: pneumatolytic phase (Sn), deposition of the association with arsenopyrite, pyrrhotite, pyrite, molybdenite (Ni, Co, Mo), formation of the Cu ± Ag + Bi sulfide mineralization, galena mineralization ± Au, hydrothermal alteration processes (addition of Ba, Sr, V). The dependence of Cu on other elements is performed by multiple linear regression, resulting an equation statistically tested by F-test, and interpreted as originating in a phase of the metallogenetic processes. The shape of the Cu-Mo mineralized stockwork from Vălişor Valley area has been studied on the basis of samples from drillings, Cu trend maps at three depth levels, and a three-dimensional model.
Geomathematical characterisation of the mineralization indicators: a case study from Tincova magmatic intrusion (Romania),
Studia UBB Geologia
Available at: http://scholarcommons.usf.edu/geologia/vol56/iss2/art2