Yajing Mao

• PhD
• Professor (Associate) at Institute of Geology and Geophysics, Chinese Academy of Sciences

The Huangshandong Ni–Cu deposit is the largest magmatic sulfide deposit discovered to date in the Central Asian Orogenic Belt in northern Xinjiang, western China. The host intrusion is a 274-Ma composite mafic–ultramafic intrusion consisting of four separate intrusive units: a large layered gabbroic sequence (phase I), a sheet-like ultramafic body...

Oxygen fugacity is a key parameter in controlling the petrogenesis of mafic-ultramafic rocks and their associated sulfide mineralization, especially in convergent settings. This study uses new and previously published experimental data on olivine-sulfide pairs to reparameterize an expression for oxygen barometry using the distribution coefficient K...

The Jinchuan intrusion is the largest single magmatic nickel sulphide deposit in the world. Sulphide mineralization mainly occurs in two segments (I and II). The crystal size distributions (CSDs) of olivines in the two segments are distinctly different. For all olivines in the two segments, their grain sizes and values of the clustering index R inc...

The Kalatongke magmatic Ni-Cu deposit features high Ni-Cu grades compared with other Ni-Cu deposits in the Central Asian orogenic belt. The sulfides, mainly hosted by olivine norite and gabbronorite, are characterized by high Cu/Ni ratios. There is wide variety of textural relationships in the mineralized rocks, including globular, sulfide matrix,...

Olivine is an important mineral in mafic-ultramafic rocks and records various crustal and mantle processes in basaltic magma. Generally, phosphorus (P) is immobile in olivine and its zoning tends to record magmatic processes. In contrast, lithium (Li) is one of the most mobile elements in olivine and tends to be redistributed by postcumulus to hydr...

Olivine (Fo80-88) from the Shitoukengde deposit exhibits low levels of Ca, Cr, and Al (< 220 ppm) and varying Ni content. The low Ca-Cr-Al contents in olivine and subsolidus temperatures (600–900 °C) indicated by olivine-spinel thermometers align with subsolidus equilibria, emphasizing substantial postcumulus modifications. Therefore, the postcumul...

Alteration Process and Water Source of magmatic Ni-Cu Deposit in Orogenic Belt— H & O Isotopes of Huangshannan Deposit in Eastern Tianshan

Nickel contents of olivine have been widely used as petrogenetic indicators and as fertility indicators for magmatic sulfide potential of mafic-ultramafic intrusions, on the assumption that olivines crystallized from magmas that had equilibrated with sulfide liquid should be relatively depleted in Ni compared with a sulfide-free baseline. This has...

Spinel minerals occur as inclusions in both silicates and sulfides in the Kalatongke magmatic Ni-Cu deposit in NW China, showing textural and compositional variations. The spinel enclosed in olivine and other silicates (orthopyroxene, clinopyroxene, and hornblende) is predominantly Cr-magnetite with minor Cr-spinel, having wide variations in MgO (0...

Alkaline rocks are generally enriched in rare metals (e.g., Nb, Ta, and Zr) and rare earth elements (REE), but the key factors controlling Nb-Ta-REE enrichment remain unclear. The Boziguoer Nb (Ta-Zr-Rb-REE) deposit in Southwest Tianshan (northern margin of Tarim Basin) is China’s largest, with reserves of 0.32 Mt Nb2O5 and 0.02 Mt Ta2O5. It is an...

Magnetite is a common accessory mineral and an indicator to magma evolution and sulfide fractional crystallization in magmatic NiCu sulfide deposits. The Kalatongke magmatic sulfide deposit at the southern margin of the Central Asian Orogenic Belt is composed of 11 mafic intrusions. The sulfide orebodies (Y1, Y1 deep, and Y2) are hosted by three sm...

Magmatic Ni-Cu sulfide deposits in orogenic belts have distinct petrological and geochemical features compared with world-class intraplate magmatic deposits. One such feature is the presence of abundant primary hydrous minerals such as phlogopite and amphibole, indicating a H2O-rich parental magma. However, the origin and nature of the fluids have...

The Tulaergen magmatic Ni–Cu deposit is related to mafic‐ultramafic rocks of the Central Asian Orogenic Belt. The ore‐host rocks are lherzolite and websterite and the major ore types are net‐textured and sparsely disseminated ores. The disseminated ores host high‐Fo (82–85) olivine and hornblende with low‐Al contents, high‐rare earth element (REE)...

Small intrusions dominated by olivine- and pyroxene-rich cumulates are well known to be favorable hosts to magmatic Ni-Cu-(Platinum Group Element—PGE) sulfide mineralization. Such intrusions are common in a variety of settings around the world, but only a very small proportion contain economically exploitable sulfides; these tend to be of conduit o...

pyrolite is a Python package for working with multivariate geochemical data, with a particular focus on rock and mineral chemistry. The project aims to contribute to more robust, efficient and reproducible data-driven geochemical research.

Various types of igneous suites occurred between 930 Ma and 890 Ma in the North China craton are known to represent a large igneous province (LIP). However, the magma plumbing system of this LIP and its potential consequence to a breakup event are poorly understood. We report morphology, crystal size distribution of plagioclase, and whole-rock and...

Sulfide Cu isotope systematic has been used as a metallogenic tracer in various deposits; however, only rarely in magmatic Ni-Cu sulfide deposits. Here we present chalcopyrite δ³⁴S and δ⁶⁵Cu data for the Kalatongke and Baishiquan Ni-Cu sulfide deposits in the Central Asian Orogenic Belt. The Kalatongke deposit yields δ³⁴S of −3.99‰ to 3.30‰ and δ⁶⁵...

The early Permian Kalatongke CuNi sulfide deposit in the Central Asian Orogenic Belt (CAOB) is the most important CuNi deposit in northern Xinjiang, NW China. It is hosted mainly by mafic intrusions, which is in contrast to deposits in the Eastern Tianshan area of eastern Xinjiang that are hosted mainly by ultramafic intrusions. The controls on sul...

The Savannah (formerly Sally Malay) Ni-Cu-Co Camp is composed of a group of mineralised intrusions (Savannah and Savannah North) and petrologically similar mafic-ultramafic intrusions without known mineralisation (Sub-chamber D, Dave Hill, and Wilson’s Creek). The results of a wide range of analytical techniques (geochemical, geochronological and g...

The Permian Huangshanxi Ni–Cu-hosted intrusion, located in the southern Central Asian Orogenic Belt in NW China, is dominated by cumulus olivine and orthopyroxene. Various types of compositional zonings in cumulate phases were studied using high-resolution synchrotron X-Ray fluorescence imaging, electron microprobe, laser ablation inductively coupl...

Magmatic Ni—Cu deposits that associated with mafic–ultramafic intrusions in convergent settings could form from multiple magma pulses with age difference varying from 1 Ma to >10 Ma years. The Huangshandong deposit in NW China of the southern Central Asian Orogenic Belt was formed in such a setting. The intrusion is composed of four units formed by...

Although there are many mafic-ultramafic intrusions in the western and central regions of Mongolia, Central Asian Orogenic Belt (CAOB), no economic-grade Ni-Cu deposits have yet been discovered. To understand the economic Ni-Cu deposit potential of the intrusions in central Mongolia, the parental magma affinity and sulfide saturation of the Oortsog...

Nickel content in sulfide (Ni tenor) is an important parameter in magmatic Ni-Cu deposit. It records Ni content in magma, the degrees of magma evolution and sulfide fractionation. Generally, high-Ni tenor sulfides are believed to be associated with komatiitic magma or alteration processes. However, it is shown that some of the high-Ni tenor sulfide...

The recently discovered Kemozibayi mafic-ultramafic intrusion and its associated magmatic Cu-Ni sulfide deposits are located at the southern margin of the Chinese Altai Mountain, Central Asian Orogenic Belt in north Xinjiang, NW China. The intrusion is composed of olivine websterite, norite, gabbro and diorite. Disseminated and net-textured Ni-Cu s...

The Huangshannan magmatic Ni-Cu sulfide deposit is one of a group of Permian magmatic Ni-Cu deposits located in the southern Central Asian Orogenic belt in the Eastern Tianshan, northwest China. It is characterized by elevated Ni tenor (concentrations in recalculated 100% sulfide) in sulfide within ultramafic rocks (9-19 wt%), with values much high...

Multiple tectonic-magmatic activities occurred in the eastern sector of the Tethys since the Early Paleozoic created favorable conditions for the formation of metallic ore deposits, about 200 precious metal deposits, 12 ultra large scale deposits and about 60 large scale ore deposits have been found in the area. Tectonically, this area can be divid...

Cihai and Cinan are Permian magnetite deposits related to mafic-ultramafic intrusions in the Beishan region, Xinjiang, NW China. The Cihai mafic intrusion is dominantly composed of dolerite, gabbro and fine-grained massive magnetite ore, while gabbro, pyrrhotite + pyrite-bearing clinopyroxenite and magnetite ore comprise the major units in Cinan. C...

The Permian basalts in the eastern Tianshan, NE Xinjiang, mostly distribute along the ENE fault in this area. The Ar-Ar age of the basalts in the Tuha basin is 298 Ma. This confirms that the Tuha basalt is coeval with former basalts and sulfide-bearing mafic-ultramafic intrusion in the Tianshan region. The Tuha basalts have similar compositional fe...

The nickel-mineralized Poshi ultramafic intrusion is situated in the southern margin of Baidiwa fault. Sulfide mineralization mainly occurs in the (plagioclase-bearing ) wehrlite, lherzolite and dunite. The olivine in Poshi ultramafic rocks show wide range of compositions, with Ni 767 ×10⁻⁶ ~ 4 580×10⁻⁶ and Fo 76.8 ~ 89.6. The Mg# and Cr# in Cr-spi...

The Poyi magmatic Ni-Cu sulfide deposit is situated in the Beishan fold belt in the northeastern rim of the Tarim craton. Many Permian magmatic Ni-Cu sulfide deposits, such as those in East Tianshan, are present in the adjacent Central Asian orogenic belt to the north. The Poyi deposit is hosted in a small dike-like ultramafictroctolitic body that...

The Xinyuan intrusion of the Eastern Junggar terrane is one of the mafic–ultramafic intrusions located in the Northern Xinjiang region and is associated with the southern part of the Central Asian Orogenic Belt (CAOB). Based on the secondary ion mass spectrometry (SIMS) zircon U–Pb dating, the intrusion is 326.2 ± 1.1 Ma old. Positive zircon ɛHf(t)...

The Huangshannan mafic–ultramafic intrusion is a Permian Ni–Cu sulfide–bearing intrusion in the southern margin of the Central Asian Orogenic Belt. The intrusion consists of an ultramafic unit, which is composed of lherzolite and olivine websterite, and a mafic unit, which is composed of olivine gabbronorite, gabbronorite and leuco-gabbronorite. Th...

Interpretation of the relationship between mafic-ultramafic rocks and iron mineralization, as well as the relationship between syenite and mafic rocks in Cihai iron district is the key to understand the diagenesis, metallogenetic process and tectonic settings. SIMS Zircon U-Pb dating for diabase, gabbro-diabase in Cihai, gabbro in Cinan, and amphib...

Early Permian mafic-ultramafic complexes in Eastern Xinjiang are mainly distributed in the Jueluotage belt, Central Tianshan massif and Beishan area. The orthopyroxene in these complexes is mostly bronzite and minor hypersthene, and the clinopyroxene is composed of diopside, endiopside and augite. Systematic mineral mapping shows higher Fo and Ni c...

The Permian Huangshanxi mafic-ultramafic intrusion hosts one of the two largest magmatic sulfide deposits in the Eastern Tianshan which is situated in the southern margin of the Central Asian Orogenic Belt. In this paper we use mineral compositions and whole-rock geochemical data to decipher the genetic relationship between magma evolution and sulf...

Huangshan orefield, consisting of Huangshan, Huangshandong, Xiangshan and Huangshannan four Ni-Cu deposits in the west part of Huangshan-Jinerquan Permian mafic-ultramafic belt, is the most important nickel mineralization area in northern Xinjiang. This study choose the Huangshan (Huangshanxi in international literature) large Ni-Cu deposit as an e...

The newly-discovered Getashankou Ni-Cu deposit is located in the eastern of the Kanggur-Huangshan ductile shear fracture zone, eastern Tianshan, NW-China. There are four mafic-ultramafic intrusions, of them the intrusion I, II and III are Ni-Cu sulfide bearing intrusions. By high-precision SIMS Zircon U-Pb dating, we obtained the concordant age of...

The Kalatongk early-Permian Cu-Ni sulfide orefield, which consists of 13 small mafic intrusions and is located in the north of the central Asian orogenic belt (CAOB), is the largest Cu-Ni ore deposit in Xinjiang. Some intrusions are unexposed, and the major economic Ni-Cu sulfide ores are found within four of these intrusions, i.e., Yl, Y2, Y3 and...

The Permian Hulu intrusion is one of several sulphide-bearing Permian mafic-ultramafic intrusions in the eastern part of the eastern Tianshan located at the southern margin of the Central Asian Orogenic Belt (CAOB) in Xinjiang, NW China. The intrusion is composed of lherzolite, olivine websterite, gabbro, and gabbro-diorite. Disseminated and net-te...

The Northern Xinjiang is characterized by a large number of Permian mafic-ultramafic complexes with magmatic Cu-Ni sulfide mineralization in different tectonic unit. The identification of the top and bottom of these Cu-Ni sulfide-bearing mafic-ultamafic intrusions, a worldwide problem, is significant for the blind ore exploration. According to the...