A thermochemical model of Eurasian Permo-Triassic mantle plumes as a basis for prediction and exploration for Cu-Ni-PGE and rare-metal ore deposits

作者：Dobretsov N L^*; Borisenko A S; Izokh A E; Zhmodik S M

来源：Russian Geology and Geophysics, 2010, 51(9): 903-924.

DOI：10.1016/j.rgg.2010.08.002

• mantle plumes
• metallogeny
• thermochemical model
• geochronology
• Ar-Ar
• U-Pb
• magmatism
• Eurasia

Four stages of the thermochemical plume-lithosphere interaction generating a broad mushroom-like head of plume and especially fourth regressive cooling phase have the important role for metallogeny. The analysis of a thermochemical plume model together with recent geological and geochronological data on magmatic ore systems in the Siberian, Tarim, Emeishan, Central European, and some other large igneous provinces (LIPs) enabled the following characteristics of the metallogeny in large igneous provinces to be revealed:
(1) the specific combination of mineralization types, which include magmatic Cu-Ni-Pt and Fe-Pt; hydrothermal Ni-Co-As (+/- Ag, U, Au), Au-As, Ag-Sb, Au-Hg, Sb-Hg and stratiform Cu (copper-bearing sandstones and shales enriched in Co, Ni, Ag, Pt);
(2) the areal or spot-like pattern of the location of mineralization types (opposed to the linear-belt localization in subduction and rift settings);
(3) the zoned distribution of mineralization types relative to LIPs' centers, with Cu-Ni-Pt, Fe-Pt and stratiform Cu mineralization localized in a LIP center, and hydrothermal mineralization bound to a LIP periphery;
(4) the essential contemporaneity of the formation of each mineralization type in LIPs, and the existence of coeval but spatially separated Cu-Ni-Pt, Ni-Co-As and Au-As deposits;
(5) the close linkage between different mineralization types and particular pulses of mafic, alkaline mafic, and felsic magmatism;
(6) the unified succession of ore-forming events;
(7) the close relationship between the extent of mineralization and LIP igneous volumes, which in turn depend on the plume heat power. The major characteristics of localization of different mineralization types within LIPs, the timing and genetic relationships between mineralization and types of magmatism, as well as specific geological controls on ore formation provide a basis for establishing new geological, magmatic, litological, and geochemical criteria crucial for predicting and targeting new mineralization within LIPs.

• 出版日期2010-9