Application of PXRF in sediment analysis for geochemical prospecting in Dragon Horn area on the southwestern Indian Ridge

Abstract

Polymetallic sulfides associated with hydrothermal activity near the mid-ocean ridges are importantpotential replacement resources in the future, while their exploration techniques and methods are relatively scarce at present. The Portable X rayFluorescence Spectroscopy(PXRF) is a new technology developed for in situ rapid analysis in field, and it has been applied in outcrops rock geochemical analyzing, and evaluation of soil heavy metal pollution.In this study, we applied PXRF in geochemical composition analyzing of sediments collected from the Dragon Horn area on the Southwest Indian Ridge, to determine possible location of potential hydrothermal actives by the spatial distribution of elements. The results show that sediments in the study area are consist of calcareous sediments, bedrock debris, hydrothermal ore-forming elements, etc.Some samples show relatively high concentrations of hydrothermal ore-forming elements, which are obviously affected by hydrothermal activities. Based on the C-N fractural method, the threshold anomaly of Cu, Zn, Fe, Mn and As were determined.According to their spatial distribution characteristics of the above elements, six anomalousareas were identifiedin the study area, three of which were consistent with known identified hydrothermal areas, and the other three anomalous areas may represent undiscovered hydrothermal activities.This study provides new strategies for hydrothermal sulfide exploration on mid ocean ridges.

Keywords

• portable x ray fluorescence spectroscopy
• hydrothermal activity
• geochemistry
• sediment
• mid ocean ridge of indian