Metallogeny of deep structures of the Earth’s crust in Southern Sikhote-Alin: Evidence from gravity data

Abstract

The spatial relations between ore deposits in Sikhote-Alin and deep density inhomogeneities of the Earth’s crust down to a depth of 30 km have been examined. The ore areas and regions show a discrete correlation with the anomalies of the normalized density of the equivalent spherical sources of gravity anomalies at depths of 1 to 2, 4 to 5, 10–12, and 24 km presumably provoked by magmatic bodies of different compositions. The depth of the magmatic bodies with the intermediate-to-basic composition of the initial magmas and the southeastward-decreasing vertical range of their correlation with the ore regions depend on their structural position. In the case of magmatic bodies of felsic and mixed compositions, the metallogenic specialization of the corresponding ore-magmatic systems is correlated with their inferred vertical range. Tin ore systems are characterized by a smaller vertical range (5–10 km) of the correlation with density inhomogeneities, whereas tin-tungsten-gold ore systems are marked by a wider range (20–25 km). Tin-lead-zinc systems occupy an intermediate position (12–20 km). The ore-controlling role of the boundaries between the lithostructural complexes of the Earth’s crust and the central-type structures in the distribution of deep sources of ore mineralization is shown.