The Formation of the Jiaodong Gold Province

Abstract

Gold deposits in Jiaodong, termed Jiaodong‐type, are tectonically located in the southeastern margin of the North China Craton. Their major features are reviewed in this paper to highlight the differences between Jiaodong deposits and other genetic types of gold deposits. The mineralization was synchronized with asthenosphere upwelling indicated by syn‐ore OIB‐like mafic dike and large‐scale crustal thinning suggested by decrease of Sr/Y from pre‐ore to syn‐ore granites. Asthenosphere upwelling induced by the roll‐back of Paleo‐Pacific Plate drove partial melting of lithospheric mantle and devolatilization, which induced the release of the ore‐forming fluids. In concomitant with magmatic records, mineralization migrated from the western Jiaobei terrane (133–127 Ma) to the eastern Sulu orogenic belt (114–108 Ma), corresponding to the eastward roll‐back of Paleo‐Pacific Plate. Gold mineralization in Jiaodong formed in the transitions of ductile to brittle deformation, rapid to slow crustal uplift, and regional compression to extension. In the regional‐scale, the gold deposits in the Jiaobei terrane are mostly situated at intersections between NE‐trending faults and EW‐trending basement faults, and gold orebodies dominantly controlled by the lithologic contacts between Precambrian metamorphic rocks and Mesozoic granites. The mineralization was dominated by the disseminated‐veinlet ores related to quartz–sericite alteration in strong cataclasite‐breccia zone, with subsidiary thick quartz‐sulfide veins developed in secondary fault zones. The ore‐forming fluids belong to a H2O–CO2–NaCl±CH4 system and show minor variations in salinity among different types of ore. Structure‐fluid feedback involving fluid‐rock reaction and hydrofracturing triggered the fluid phase separation and resultant gold deposition. The Jiaodong gold deposits are distinct from orogenic and intrusion‐related gold deposits in terms of tectonic setting, origin of ore‐forming fluids, and mechanism of gold deposition.

Two-Stage Superimposed Gold Mineralization in the Xiejiagou Gold Deposit, Shandong Province: Insights from Fluid Inclusions, H-O-S Isotopes, and Trace Elements

“…( 2 [59,60], the fact that late Archean to early Proterozoic regional metamorphism identified in the study area [61][62][63] significantly predates the formation of the Xiejiagou gold deposit and the lack of early Cretaceous metamorphism strongly precludes the involvement of metamorphic fluid. This conclusion is consistent with previous studies that the Precambrian metamorphism has no genetic role to play in the formation of the Mesozoic gold mineralization in the Jiaodong area [64,65]. (4) As shown in the Ni-Co and Sb/Bi-As/Ag diagram, most pyrite samples of the Xiejiagou gold deposit fall between magmatic-related and hydrothermal-related pyrites (Figure 13a) or magmatic-related pyrite (Figure 13b), rather than metamorphic hydrothermal-related pyrite [66][67][68].…”

Hydrothermal Alteration Processes of Xincheng Gold Deposit Jiaodong Peninsula, China: Constraints from Composition of Hydrothermal Rutile

“…The 193 nm ArF excimer laser, homogenized through an advanced beam delivery system, was precisely focused on the mineral surface, delivering a fluence of 10-12 J/cm 2 . Measured masses included 23 Na, 24 Mg, 27 Al, 29 Si, 31 P, 39 K, 44 Ca, 49 Ti, 55 Mn, 57 Fe, 7 Li, 9 Be, 11 B, 45 Sc, 51 V, 52 Cr, 59 Co, 60 Ni, 63 Cu, 66 Zn, 71 Ga, 73 Ge, 75 As, 85 Rb, 88 Sr, 89 Y, 91 Zr, 93 Nb, 95 Mo, 111 Cd, 118 Sn, 133 Cs, 137 Ba, 139 La, 140 Ce, 141 Pr, 146 Nd, 147 Sm, 153 Eu, 157 Gd, 159 Tb, 163 Dy, 165 Ho, 166 Er, 169 Tm, 172 Yb, 175 Lu, 178 Hf, 181 Ta, 182 W, 209 Bi, 208 Pb, 232 Th, and 238 U. Each acquisition process began with a 20 s background measurement to establish a baseline (gas blank), followed by a 60 s ablation period where a 30 µm spot diameter was used at a repetition rate of 6 Hz.…”

“…The study of fluid-rock reaction processes is crucial for revealing element migration patterns during hydrothermal alteration, analyzing the mechanisms of hydrothermal alteration, and exploring the evolution of hydrothermal fluids, the activation, migration, and precipitation mechanisms of ore-forming elements [2]. Despite previous studies on the hydrothermal alteration of gold deposits in Jiaodong, which primarily focused on the major and trace element composition of different altered rocks to reveal the patterns of element migration between various alteration zones [2][3][4][5][6][7], it has been found that the hydrothermal alteration in Jiaodong gold deposits exhibits multi-stage superposition characteristics with complex mineral microstructures. However, the use of bulk mineral analysis to obtain results such as major and trace elements, isotopes are average values for different stages, which may differ from their actual geological significance, cannot accurately constrain the hydrothermal alteration process or mineralization process [8][9][10][11][12][13].…”

Geochronology, Geochemistry, Fluid Inclusion and C, O Isotope Compositions of Calcite Veins in the Paleogene of the Jiangling Basin, South China: Implications for Fluid Evolution and Brine Potash Mineralization

“…The rare earth elements, fluid inclusions and carbon and oxygen isotopes have been widely used to characterize and trace the source and evolution of hydrothermal fluids (e.g., Ohmoto and Rye, 1979;Hoefs, 1987;Bau and Dulski, 1995;Demé ny and Haranqi, 1996;Suchy et al, 2000;Deng et al, 2009;Ren et al, 2015;Du et al, 2017;Pei et al, 2017;Perry and Gysi, 2018;Quandt et al, 2018;Zhang et al, 2020;Deng et al, 2022;Wang et al, 2022). Hydrothermal calcite is predominant in veins from the Balingshan area of the Jiangling Basin, and is regarded as the optimal mineral for the examination of fluid activity.…”