scholarly journals Metasomatized lithospheric mantle for Mesozoic giant gold deposits in the North China craton

Geology ◽  
2019 ◽  
Vol 48 (2) ◽  
pp. 169-173 ◽  
Author(s):  
Zaicong Wang ◽  
Huai Cheng ◽  
Keqing Zong ◽  
Xianlei Geng ◽  
Yongsheng Liu ◽  
...  
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Mantle Metasomatism ◽  
Gold Deposits ◽  
Mantle Xenoliths ◽  
Lode Gold ◽  
The North ◽  
Craton Destruction ◽  
Lode Gold Deposits

Abstract The origin of giant lode gold deposits of Mesozoic age in the North China craton (NCC) is enigmatic because high-grade metamorphic ancient crust would be highly depleted in gold. Instead, lithospheric mantle beneath the crust is the likely source of the gold, which may have been anomalously enriched by metasomatic processes. However, the role of gold enrichment and metasomatism in the lithospheric mantle remains unclear. Here, we present comprehensive data on gold and platinum group element contents of mantle xenoliths (n = 28) and basalts (n = 47) representing the temporal evolution of the eastern NCC. The results indicate that extensive mantle metasomatism and hydration introduced some gold (<1–2 ppb) but did not lead to a gold-enriched mantle. However, volatile-rich basalts formed mainly from the metasomatized lithospheric mantle display noticeably elevated gold contents as compared to those from the asthenosphere. Combined with the significant inheritance of mantle-derived volatiles in auriferous fluids of ore bodies, the new data reveal that the mechanism for the formation of the lode gold deposits was related to the volatile-rich components that accumulated during metasomatism and facilitated the release of gold during extensional craton destruction and mantle melting. Gold-bearing, hydrous magmas ascended rapidly along translithospheric fault zones and evolved auriferous fluids to form the giant deposits in the crust.

Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts

2020 ◽  
Vol 132 (11-12) ◽  
pp. 2353-2366
Author(s):  
Yao Xu ◽  
Hongfu Zhang
Keyword(s):  
Early Cretaceous ◽  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Mantle Xenoliths ◽  
Liaoning Province ◽  
Northern Margin ◽  
Secular Evolution ◽  
The North ◽  
Peridotitic Mantle

Abstract Abundant zoned olivine xenocrysts from Early Cretaceous basalts of the Yixian Formation in western Liaoning Province, China, contain critical information about the nature and evolution of the lithospheric mantle of the northern North China Craton. These olivine xenocrysts are large (600–1600 µm), usually rounded and embayed, with well-developed cracks. Their cores have high and uniform forsterite (Fo) contents (88–91), similar to the peridotitic olivine entrained by regional Cenozoic basalts. Their rims have much lower Fo contents (74–82), comparable to phenocrysts (72–81) in the host basalts. These characteristics reveal that the zoned olivine has been disaggregated from mantle xenoliths and thus can be used to trace the underlying lithospheric mantle at the time of basaltic magmatism. The olivine cores have high oxygen isotope compositions (δ18OSMOW = 5.9–7.0‰) relative to the normal mantle value, suggesting that the Early Cretaceous lithospheric mantle was enriched and metasomatized mainly by melts/fluids released from subducted oceanic crust that had experienced low-temperature hydrothermal alteration. Preservation of zoned olivine xenocrysts in the Early Cretaceous basalts indicates that olivine-melt/fluid reaction could have been prevalent in the lithospheric mantle as an important mechanism for the transformation from old refractory (high-Mg) peridotitic mantle to young, fertile (low-Mg), and enriched lithospheric mantle during the early Mesozoic.

Early Devonian ultrapotassic magmatism in the North China Craton: geochemical and isotopic evidence for subcontinental lithospheric mantle metasomatism by subducted sediment-derived fluids

2019 ◽  
Vol 158 (1) ◽  
pp. 158-174 ◽  
Author(s):  
Xiaolu Niu ◽  
Yildirim Dilek ◽  
Fei Liu ◽  
Guangying Feng ◽  
Jingsui Yang
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Mantle Metasomatism ◽  
Alkaline Magmatism ◽  
Subcontinental Lithospheric Mantle ◽  
Early Devonian ◽  
Isotopic Compositions ◽  
The North

AbstractWe report new U–Pb zircon age data, zircon in situ oxygen isotope, mineral chemistry, whole-rock geochemistry and Sr–Nd isotopic compositions from the Early Devonian ultrapotassic Gucheng pluton in the North China Craton, and discuss its petrogenesis. The Gucheng pluton is exposed in the northern part of the North China Craton and forms a composite intrusion, consisting of K-feldspar-bearing clinopyroxenite, clinopyroxene-bearing syenite and alkali-feldspar syenite. Mineral phases in these lithologies include clinopyroxene (Wo43–48En19–35Fs18–38), sanidine (An0Ab3–11Or89–97), and subordinate titanite, andradite and Na-feldspar. These rocks show homogeneous Sr but variable Nd isotopic compositions, and have relatively high zircon in situ oxygen isotopes (δ18O = 5.2–6.7). The Gucheng plutonic rocks formed through fractional crystallization and accumulation from ultrapotassic magmas, which were originated from partial melting of metasomatic vein systems in the subcontinental lithospheric mantle of the North China Craton. These vein networks developed as a result of the reactions of fluids derived from subducted pelitic sediments on the downgoing Palaeo-Asian ocean floor with the enriched, subcontinental lithospheric mantle peridotites. Sensitive high-resolution ion microprobe (SHRIMP) U–Pb zircon dating has revealed a crystallization age of 415 Ma for the timing of the emplacement of the Gucheng pluton that marks the early stages of alkaline magmatism associated with the Andean-type continental margin evolution along the northern edge of the North China Craton facing the Palaeo-Asian Ocean.

Gold deposits of the northern margin of the North China Craton: multiple late Paleozoic–Mesozoic mineralizing events

2002 ◽  
Vol 37 (3) ◽  
pp. 326-351 ◽  
Author(s):  
Craig J. Hart ◽  
Richard J. Goldfarb ◽  
Yumin Qiu ◽  
Lawrence Snee ◽  
Lance D. Miller ◽  
...  
Keyword(s):  
North China Craton ◽  
North China ◽  
Gold Deposits ◽  
Late Paleozoic ◽  
Northern Margin ◽  
The North

scholarly journals Abnormal lithium isotope composition from the ancient lithospheric mantle beneath the North China Craton

2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Yan-Jie Tang ◽  
Hong-Fu Zhang ◽  
Etienne Deloule ◽  
Ben-Xun Su ◽  
Ji-Feng Ying ◽  
...  
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Isotope Composition ◽  
Lithium Isotope ◽  
The North

Au-Ag-Te–RICH MELT INCLUSIONS IN HYDROTHERMAL GOLD-QUARTZ VEINS, XIAOQINLING LODE GOLD DISTRICT, CENTRAL CHINA

2021 ◽  
Author(s):  
Wei Jian ◽  
Jingwen Mao ◽  
Bernd Lehmann ◽  
Nigel J. Cook ◽  
Guiqing Xie ◽  
...  
Keyword(s):  
Melt Inclusions ◽  
Experimental Studies ◽  
Gold Deposits ◽  
Central China ◽  
Lode Gold ◽  
Quartz Veins ◽  
The North ◽  
Reduction Mechanisms ◽  
Adsorption Reduction ◽  
Lode Gold Deposits

Abstract We present petrographic and microthermometric evidence for precipitation of Au-Ag-Te–rich melt directly from hydrothermal fluids and subsequent entrapment as primary melt inclusions within pyrite from quartz veins of the Xiaoqinling lode gold district, southern margin of the North China craton. We propose the formation of Au-Ag-Te–rich melt through adsorption-reduction mechanisms on pyrite and subsequent growth of the melt nuclei via direct scavenging of metals from fluids. Because neither initial formation nor later growth of the melt require saturation of the ore fluid with respect to the constituent metals, this mechanism offers a new understanding of the enrichment of low-abundance ore components, such as gold. Our model may thus partly explain the discrepancy between the high gold solubilities reported from experimental studies and the much lower gold concentrations usually measured in natural fluids. This study also implies that Au-Ag-Te–rich melt has probably gone unrecognized in other lode gold deposits in which Au-Ag tellurides are present.

Refertilization of lithospheric mantle beneath the North China Craton in Mesozoic: Evidence from in situ Sr isotopes of Fuxin peridotite

Lithos ◽  
2020 ◽  
Vol 364-365 ◽  
pp. 105478 ◽  
Author(s):  
Dongya Zou ◽  
Hongfu Zhang ◽  
Xiaoqi Zhang ◽  
Huiting Zhang ◽  
Benxun Su
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Sr Isotopes ◽  
The North
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