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The Cretaceous Dagzhuka ophiolite lies in the middle segment of the Yarlung-Zangbo suture zone, Tibet, and has a well-preserved ophiolitic section including a mantle sequence, cumulate complex, diabase dyke swarm and basaltic lavas. Compared to the primitive mantle, tectonized peridotites in the Dagzhuka ophiolite are depleted in Al, Ca, Ti and high field strength elements, but relatively enriched in large ion lithophile elements (Rb, Ba, Th). They have U-shaped, chondrite-normalized REE patterns suggesting an early stage of depletion by partial melting, followed by enrichment from slab-derived fluids. These features support a model in which the mantle peridotites at Dagzhuka formed in a forearc setting. The diabases and basalts are low-K tholeiites depleted in LREE, with compositions similar to N-MORB. However, these rocks are strongly depleted in Nb and Ta but enriched in Th and Rb, features characteristic of island arc lavas. Thus, the Dagzhuka ophiolite is believed to have formed in a supra-subduction zone environment, possibly a fore-arc basin.

The total PGE amount (SPGE) of mantle peridotite in the Jiding ophiolite is slightly higher than that of the primitive mantle, but the PGE contents of basalt are higher than those of the mid-ocean ridge basalt (MORB), with obviously lower Pd/Ir ratios. The accumulates, dyke swarm and basalts show remarkable negative Pt and positive Rh anomalies, resulting in the special N-type PGE patterns. Mantle peridotite and crustal rocks have similar distribution patterns. It is proposed that the PGE distribution patterns in the Jiding ophiolite are closely related with a higher degree of partial melting of the mantle in this region. Magmatic crystallization-differentiation led to PGE fractionation, thus making the contents of PGE in the accumulates decrease in the ascending direction. The higher content of Au in the Jiding ophiolite is the result of metasomatic alteration at later stages. Pt-Pd fractionation indicates that both the PGEs are controlled by their alloy and sulfide phases. Positive Rh anomalies seem to be related with higher oxygen fugacity in the melts.

The total PGE amounts of mantle peridotites in the Dazhuka ophiolite, Tibet, are 28.37–50.67 ng/g, slightly higher than those of mantle peridotites in the primitive mantle, and typical ophiolites in the world, and the Alps-type mantle peridotites. The PGE distribution patterns in the Dazhuka mantle peridotites are also different from those of the mantle peridotites of partial melting relict origin. The Dazhuka mantle peridotites have relatively high total PGE amounts and are enriched in Pt, Pd, and Ru. Their PGE distribution patterns belong to the positively inclinedor swallow-type patterns. The PGE distribution patterns in the mantle peridotites of partial melting relict origin belong to the negative-slope patterns or flat patterns. This reflects the unique features of the upper mantle in this region. Relative enrichment in Pt and Pd, as well as in the incompatible elements Cu, Au, Cs, Rb, Ba, Th, U and LREE, indicates that the partial melting-derived relict mantle peridotites in the Dazhuka ophiolite had experienced intensive permeating and mixing processes of the melt and fluid both containing abundant incompatible elements.

The sandstone-type Cu deposits in the Chuxiong Basin occur in the Cretaceous Gaofengsi Formation and the Maotoushan Formation and the orebodies are stratoid and lenticular in form, structurally controlled by their stratigraphical position. Ore structures are dominated by impregnated and striped ones. In addition, it has been observed that copper mineralization is controlled by water-discharge and deformation structures. Orebodies are commonly seen on the gently inclined limbs of the anticline, with the involution front. Copper mineralization shows a distinct zonation. S, Pb isotope and REE data suggest that the copper would stem from the country rocks and the sulfur largely from the lower strata. During diagenesis oxidized Cu-bearing brines derived from the upper parts and reduced brines from the lower parts are involved in metallogenetic reactions in the stress neutral plane, which is the key to the formation of copper deposits in the Chuxiong Basin.