The characteristics of V, Sc, Cr and Ni within the Cambrian terrigenous-carbonate deposits found in the Syuldyukar kimberlite field (Western Yakutia)

The investigation of the Syuldyukar kimberlite field, located within the Yakut diamond-bearing province, involved approximately 4,000 X-ray fluorescence (XFA) analyses and 150 inductively coupled plasma atomic emission spectroscopy (ICP AES) analyses on the host sedimentary rocks of the Upper Cambrian Holomolokha formation in proximity to the kimberlite bodies. The results indicated a disruption in the correlation ratios when compared to background concentrations, while subclark levels of vanadium (V), scandium (Sc), chromium (Cr), nickel (Ni), and other elements remained consistent. The elements were divided into three categories: typomorphic elements for kimberlites (Cr, Ni, Co), elements associated with carbonatites (barium (Ba), strontium (Sr), neodymium (Nd), zirconium (Zr)), and elements characteristic of basalts (V, Sc, zinc (Zn)). High positive correlation coefficients were established for the specified elements in the background concentrations. However, ICP analyses indicated significant decreases in the correlation between elements from different groups in the near-kimberlite space at the Syuldyukar site. X-ray diffraction (XRD) studies showed that in the compression areas, the correlation ratios of various elements were inconsistent when compared to the stretching areas. The analysis of the XRF and ICP data reveled that the average elemental concentrations in the background and near-tube space were nearly identical, except for some unusual hurricane values, with variations showing only slight changes. The positive correlation of several elements likely reflects background geological processes, including sedimentation in a marine basin and subsequent transformations such as hypergenesis, diagenesis, and catagenesis. The significant decrease in correlation coefficients, even with background concentrations remaining stable, is likely due to the redistribution of elements in the fluid resulting from phreatomagmatic explosions linked to the intrusion of kimberlites. Aqueous chloride fluids were observed to most actively redistribute elements in areas experiencing local tectonic compression. The identified changes in the correlation ratios of background elemental concentrations in sedimentary rocks containing kimberlite could act as a new indicator for locating hidden diamond-bearing kimberlites.