By Sergey M. Rodionov1, Alexander A. Obolenskiy2

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BIF is hosted in marine volcaniclastic and clastic sedimentary rocks with minor conglomerate that are metamorphosed to amphibolite and greenschist facies. The belt is interpreted as forming in a passive continental margin or aulacogen that was subsequently regionally metamorphosed and thrusted (Zhang Yixia and others, 1986).

REFERENCES: Zhang Yixia and others, 1986.

Yanliao 1 Metallogenic Belt of

Chemical-Sedimentary Fe and Mn Deposits

(Belt YL-1) (North China)

This Late Paleoproterozoic metallogenic belt is hosted in lower part of Sino-Korea platform sedimentary cover and occurs in the eastern Yanshan Mountains in the East Hebei Provinces. The belt is 200 to 300 km long, over 50 km wide, and strikes in east-west. The deposits in the belt are mainly hosted in the late Paleoproterozoic Changcheng System. The host rocks are siltstone, quartzite, and schist. The significant deposit is at Pangjiapu.

Pangjiapu Chemical-Sedimentary Fe and Mn Deposit

This deposit (He, Beiquan, 1993) consists of bedded and stratiform deposits that are concordant to host sandstone and argillite in the Lower Changlinggou Formation in the Mesoproterozoic Changcheng System of the North China Platform. The deposits are 2,000 to 5,000 m long, 460 to 2,000 m wide and 0.18 to 5.38 m thick. Deposit minerals are hematite, minor magnetite, siderite, quartz, chamosite, and calcite. The deposit is interpreted as forming in an oxidation zone in a shallow sea to tidal environment. The deposit is medium-size with reserves of 100 million tonnes grading 45% Fe.

Origin and Tectonic controls for

Yanliao 1 Metallogenic Belt.

The belt is interpreted as forming during sedimentation in a shallow marine basin (Yanliao Basin) along Late Paleoproterozoic passive contimental margin of Sino-Korean Craton (Wang Hongzhen, 1985). The Paleoproterozoic part of the basin consists of the following geological units from older to younger: (1) quartz sandstone intercalated with conglomerate and shale; (2) shale with mainly ferrous sandstone at the bottom; (3) dolomite intercalated with shale and sandstone; (4) quartz sandstone intercalated with siltstone, dolomite, and intermediate to mafic volcanic rock; (5) dolomite and dolomitic limestone and minor basal Mn bearing shale and dolomite.

REFERENCES: Wang Hongzhen, 1985

Jiliaojiao Metallogenic Belt of

Sedimentary Metamorphic Borate,

Sedimentary Metamorphic Magnesite and

Talc Replacement,

Banded Iron Formation (BIF, Superior Fe),

Korean Pb-Zn Massive Sulfide

Metamorphic Graphite, and Au in Shear Zone

and Quartz Vein Deposits

(Belt JLJ) (Northeastern China)

This Late Paleoproterozoic metallogenic belt contains numerous large to super-large deposits. The belt extends from the Eastern Jilin Province, to Liaodong Peninsula, and farther south to Shandong Peninsula. The belt is 800 km long and 50 to 100 km wide, and is hosted in the Paleoproterozoic East Shandong-East Liaoning-East Jilin rift basin that overlaps the Archean Jilin-Liaoning-East Shandong terrane of the Sino-Korea Craton. The varied deposits in the belt are closely related to a extensive and thick sequence of volcanic rock, clastic rock, and carbonate (Ji’an, Laoling, Laohe, Jingshan and Fenzishan Groups). Metallogenic belt is a composite that includes several mineral deposit types. The most significant deposits are at Wengquangou, Xiafangshen, Fanjiapuzi, Dalizi, Qinchengzi, Zhangjiagou, Baiyunshna, Nancha, and Nanshu.

Wengquangou Sedimentary Metamorphic Borate Deposit

This deposit (Peng, and others, 1993; Editorial Committee of the Discovery History of Mineral Deposits of China, 1996) is hosted in an unusual Paleoproterozoic volcanic and sedimentary sequence, including tourmaline-bearing rock, and albite-and microcline-bearing rocks. Ludwigite also occurs. The deposit is hosted in Mg magnesian carbonates and Mg silicate rock metamorphosed to amphibolite facies and intensely deformed at about 1.9 Ga. Nine stratiform deposits occur in metamorphosed rock units in a syncline that extends in east-west for about 4.5 km. The largest no.1 lode extends 2,800 m east-west and 1,500 m wide north-south, and averages 45 m thick. Deposit types are metasedimentary (type A) and hydrothermal (type B). Type A is conformably hosted in stratiform magnesian carbonates (mainly magnesite). Suanite [Mg₂(B₂O₅)] is the main ore mineral and suggest derivation from B-and Mg-carbonate originaly deposited in evaporite-related sedimentary rock. Type B occurs in stratiform Mg-silicates in breccia or deformed bands and are the most important deposits in the area. Breccia fragments consist of laminated, fine-grained farsterite and diopside in a matrix of suanite and magnesite. Breccia contains fractured Mg-silicates with irregular shape fragments in the matrix. Deposit averages about 30.65% Fe and to 7.23% B₂O₃. Many interpretations exist for the the origin of mineral deposit, including metasomatism, migmatization hydrothermal activity, metamorphosed hydrothermal-sedimentary deposit, and others. A recent study suggests formation during metamorphism of an evaporite sequence in a Paleoproterozoic rift (Peng and others, 1993; Peng and Palmer, 1994). The deposit is superlarge with reserves of 21.9 million tonnes B₂O₃.

Xiafangshen Sedimentary Metamorphic Magnesite Deposit

This deposit (Li, Yuya and others, 1994) occurs in the Proterozoic Eastern Liaoning rift zone in the Paleoproterozoic Dashiqiao Formation. The host rocks are mainly two-mica quartz schist, sillimanite-kyanite-straurolite two-mica schist, magnesite marble, and dolomitic marble, with a total thickness of 3516 m. Deposit layers occur in a north-northeast-striking monocline that extends 3,250 m. Deposits are multiply layered and stratiform. thelowest deposit is dominant, extends 3,626 m along strike and averages 205 m thick. Deposit minerals are mainly massive with secondary banded deposits consisting of magnesite and minor talc, tremolite, dolomite and clinochlorite. Magnesite is dominantly medium-and coarse-grained and contains 47.30% MgO. The deposit is superlarge with reserves of 258 million tonnes.

Fanjiapuzi Talc (Magnesite) Replacement Deposit

This deposit (Li, Yuya and others, 1994) occurs in the eastern Liaoning Proterozoic rift zone and closely associated with Mg host rocks in the upper part of the Paleoproterozoic Dashiqiao Formation. The deposit occurs on the north limb of a north-northeast-trending synclinorium in the huge Yingkou-Dashiqiao-Fanjiapuzi magnesite belt. Deposits are stratiform and lenticular and are comfortable with wallrocks. Coarse-grained magnesite often occurs in talc ores. Where talc content is over 70%, hand sorting produces a high quality, rose or white ores that contains 30 to 32% MgO, 59 to 62% SiO₂, <19% CaO and <0.5% Fe₂O₃. Where ore whiteness is over 85 and talc content is between 50% and 90%, flotation process produces a high quality talc powder. The deposit is superlarge with reserves of 36 million tonnes.

Dalizi Banded Iron Formation (BIF, Superior Fe) Deposit

This deposit (Zhang, Qiusheng, and others, 1984a, b) consists of various bedded, stratiform and lens-shaped deposits that occur in a 10-km-long area that is. A single deposit ranges to 10 to 30 m thick. Deposits are concordant to the deposit-hosting strata. Three types of deposits are recognized according to major ore minerals, siderite, hematite, and magnetite. Siderite deposits are mostly bedded, are concentrated in carbonate rocks, are rich in Pb and Zn, and have potential for stratiform Pb-Zn deposits. Hematite deposits, that are closely associated with magnetite deposits, are massive and banded. The host strata is metamorphosed to greenschist facies and consists of silty mudstone and carbonate rocks of the Paleoproterozoic Laoling Group that are intensely folded. Deposit swarms are clustered in axes of transverse folds. The primary sedimentary environment is interpreted as a secondary shallow basin that formed in a Paleoproterozoic rift. Siderite is concentrated in carbonate sedimentary facies. The deposit is medium size.

Qingchengzi Korean Pb-Zn massive Sulfide Deposit

This deposit (Tu, Guangzhi, and others, 1989; Zhang, Qiusheng, and others, 1984b) consists of stratiform, feather, and vein masses of mainly galena, sphalerite, pyrite, and pyrrhotite, with minor arsenophyrite, chalcopyrite, bornite, and tetrahedrite that are hosted in marble of the Proterozoic Liaohe group. Ore minerals are medium-to coarse-grained, and vary from euhedral or subhedral. Ores are of the structures of dissemination, band, veinlet, network, breccia, crushed grain etc. The deposit occurs at the intersection of Yingkou-Kuandian uplift and Qianshan Mountain Range. The deposit is large with reserves of 728,900 tonnes Pb, 349,300 tonnes Zn. Average grade is 2.64% Pb, 1.90% Zn.

Baiyunshan Au in Shear Zone and Quartz Vein Deposit

This deposit (Xu Enshou, Jin Yugui, Zhu Fengshan and others, 1994) consists of lensoid, lenticular, nested, and irregular masses of pyrite, pyrrhotite, chalcopyrite, arsenopyrite, galena, and sphalerite, and gangue minerals, including quartz, sericite, K feldspar, calcite, and dolomite. Ore minerals occur along interformational folds in phyllite, mica schist, and dolomite. Ores minerals vary from massive to disseminated. Host rocks altered to quartz, sericite, and pyrite. Gold varies from fine-grained to microscopic and grades into electrum. Host rocks are slightly metamorphosed Paleoproterozoic carbonaceous, volcanic, clastic, and carbonate rocks of the Liaohe Group that is part of the Sino-Korean Craton. The deposit is medium size.

Nancha Au in Shear Zone and Quartz Vein Deposit

This deposit (Wang, Enyuan, 1989) consists of gold, pyrite, arsenopyrite, pyrrhotite, chalcopyrite, and minor galena, sphalerite, bornite, chalcocite, and magnetite. Ore minerals vary from disseminated, fine veined, brecciated, and banded. Textures are idiomorphic, hypidiomorphic-xenomorphic, and metasomatic replacement. This deposit is more than 3000 m long, strikes northwest, and is several hundred meters wide. From the southwest to northeast, three mineralized sectors are recognized. The main deposits in the first sector occur in a structurally altered zone between basal schist, quartzite, and marble of the Huashan Formation and an upper, thick dolomite marble of the Zhenzhumeng Formation. The deposits in the second and third sectors occur in a structurally altered zone in thick dolomitic marble of the Zhenzhumen Formation. The sectors vary from stratiform or lenticular, and a single sector ranges from several tens to a hundred meters long. Wide-spread carbonate and silica alteration is associated with the deposit. Other important alterations formation of arsenopyrite and pyrite. The deposit origin is controversial. The deposit is medium size.

Nanshu Metamorphic Graphite Deposit

This deposit (Zhang, Qiusheng, and others, 1984) consists of a graphite-bearing horizon that is hosted in the Paleoproterozoic Jingshan Group in three sequences: (1) marble and amphibole-plagioclase gneiss intercalated with graphite gneiss; (2) amphibole-plagioclase intercalated with marble and graphite gneiss; and (3) marble and amphibole-plagioclase gneiss. The first and second sequences contain major graphite layers. Graphite occurs in crystalline and amorphous forms. Amorphous graphite masses are soft and massive, and occur along bedding and cleavage, and are intercalated in lenses with host rocks. Crystalline graphite masses are apparently bedded, multiply layered, lenticular, and concordant to host gneiss and marble. The deposits vary from 50 to 1000 m long and extend 50 to 400 m downdip. Grade and thickness are relatively constant. Main ore mineral is graphite and gangue minerals are biotite, tremolite, quartz, microcline, plagioclase, muscovite, hypersthene, clinozoisite, garnet, apatite, and sphene. Other recoverable sulphide-minerals include pyrite, pyrrhotite, chalcopyrite, bornite, and sphalerite. Deposit exhibits gneissic, banded, and granoblastic structures. Ore mineral texture is mainly lepidoblastic. The deposit is interpreted as forming from metamorphism of organic carbon in clastic sedimentary rock that was deposited in a shallow marine environments. The deposit is large.

Origin and Tectonic Controls for

Jiliaojiao Metallogenic Belt.

The belt is interpreted as forming in a passive continental margin, possibly as part of the Paleoproterozoic East Shandong-East Liaoning-East Jilin rift. The parental rocks include intermediate and siliceous volcanic rock, clastic rocks, and very thick carbonates. During metamorphism to amphibolite and greenschist facies the host rocks were transformed into: (1) fine grained biotite, hornblende or diopside-bearing gneiss, leucocratic gneiss intercalated with graphite biotite gneiss, Al-rich gneiss, schist, amphibolite, marble and Ca-Mg silicate granofels; and (2) phyllite, muscovite-biotite schist, fine-grained leucocratic gneiss, and dolomitic marble. The environment of formation and deposit controls are debated (Zhang Qiusheng and others, 1984, Fang Ruiheng, 1994, Peng and others, 1993).

REFERENCES: Zhang Qiusheng and others, 1984, Peng and others, 1993; Fang Ruiheng, 1994.

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