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Yanliao or Yan-Liao Gold Province - Dongping, Xiaoyinpan, Zhongshangou, Honghuagou, Lianhuashan, Paishanlou, Erdaogou, Jinchanggouliang, Jinchangyu, Yuerya, Baizhangzi, Niuxinshan, Zhangquanzhuang, Dabaiyang, Zhuanshanzi |
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Super Porphyry Cu and Au
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IOCG Deposits - 70 papers
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The Yanliao (or Yan-Liao) Gold Province represents the central section of a larger belt of orogenic style lode gold deposits distributed along the ~1500 km long northern margin of the North China Craton, extending from the middle of Inner Mongolia, through northern Hebei and Liaoning, to Jilin Province. Together these deposits account for more than 900 tonnes (30 Moz) of gold.
The Yanliao Gold Province, which is mainly within the Yanshan Mountains of northern Hebei and western Liaoning provinces and parts of southern Inner Mongolia, covers an area of ~500 x 300 km with more significant depoits concentrated in 4 main clusters. It includes the following key deposits in each cluster as follows:
• Dongping,
Xiaoyinpan,
Zhongshangou,
Zhangquanzhuang,
Dabaiyang in the Zhangjiakou District, ~100 km NW of Beijing;
• Honghuagou, Lianhuashan, Zhuanshanzi and Nandawa in the Chifeng District, towards the northern limit of the craton, ~340 km NE of Beijing;
• Jinchanggouliang, Erdaogou and Paishanlou in the east-west trending Liaoxi Uplift, ~100 km ESE of Chifeng and
• Jinchangyu,
Niuxinshan,
Yuerya,
Baizhangzi in the Yanshan District ~200 km ENE of Beijing.
Each is described below, with deposit size and grade at the end of the record.
The bulk of the major orogenic gold deposits on the northern margin of the North China Craton are concentrated in the Yanshan Mountain area, where regional structures include both NNE striking faults and shear zones, and east-west trending folds and faults.
The northern margin of the North China Craton is characterised by east-west trending basement uplift blocks of metamorphosed Archaean and Paleoproterozoic gneiss, schist, granulite, amphibolite and banded iron formation that have been episodically uplifted during Variscan (Permo-Carboniferous), Indosinian (Triassic), and Yanshanian (Jurassic to Cretaceous) tectono-magmatic events. Slightly metamorphosed Mesoproterozoic to Neoproterozoic shallow marine quartzite, slate and limestone, and Paleozoic to Cretaceous shallow marine to continental sedimentary rocks, surround the uplifts. Most of the deposits are hosted by these blocks of Precambrian metamorphic rocks, although Palaeozoic and Mesozoic felsic plutons are commonly found in close proximity and host around 30% of the mineralisation.
Gold deposits and granites are associated with both Variscan and Yanshanian tectonism, although broad scale regional deformation is mainly Variscan and is best characterised by east-west striking folds and fault zones formed during the Permian early stages of ocean closure between the North China and Siberia cratons. Locally, in the eastern part of the gold province, the Variscan structures are overprinted by Yanshanian NNE trending strike slip faults.
Both Variscan (e.g., Xiaoyinpan) and Yanshanian (e.g., Dongping) gold deposits and granites are recognised in the western part of the Yanlaio area, although gold ores (e.g., Jinchangyu, Honghuagou, Jinchanggouliang and Paishanlou) found to the east are dominantly Yanshanian. The larger deposits are typically associated with the younger Yanshanian hydrothermaI systems.
Within individual districts clusters occur, such as at Jinchangyu, where associated deposits, are localised within a 6 km long by 1 km wide, NNE-trending fault cutting Archaean metamorphic rocks. Clusters of quartz and quartz albite veins are up to a few tens of metres wide, up to 300 m long, and continue to a depth of ~550 m. The veins mainly contain pyrite, lesser gold, electrum, chalcopyrite, galena, pyrrhotite, magnetite, molybdenite and trace amounts of telluride minerals.
Many of the deposits show a spatial association with granites of both orogenies. These include the Dongping, Yuerya, Niuxinshan, Baizhangzi deposits, which all contain >20 t Au and are all at least partly hosted by granites. This multi-episodic mineralisation corresponds to episodic tectonic reactivation and associated magmatism along the northern margin of the North China craton.
There is a division between deposits wholly or partly within an intrusive and those hosted in metamorphic rocks is illustrated in the Zhangjiakou district which constitutes the western cluster of deposits in the Yanliao province. This cluster includes more than 25 gold deposits, a number of which are described below (after Deng and Wang, 2016; Hart et al., 2002). These have been divided into: i). Dongping-type, including the Dongping, Hougou, Huangtuliang and Zhongshangou deposits, which are associated with the altered Carboniferous Shuiquangou syenitic complex (Cook et al., 2009; Mao et al., 2003; Wang et al., 2019); and ii). Xiaoyingpan-type, including the Zhangquanzhuang, Xiaoyingpan, Shuijingtun and Hanjiagou deposits that are hosted in metamorphic rocks of the Archaean Sanggan Group (Jiang and Nie, 1998).
As with the deposits hosted in metamorphic rocks (e.g., Jinchangyu), the granite-hosted deposits are also structurally controlled, and commonly localised by brittle secondary structures related to a major regional fault or shear zone. At the >100 t Au Dongping deposit, the largest of these granite hosted deposits, Yanshanian gold mineralisation occurs in the 327 Ma Shuiquangou syenite to monzonite batholith complex. This batholith intruded along a group of east-west trending structures that are parallel to, and about 10 km south of, the trans-crustal Shangyi-Chungli-Chicheng deep fault zone, which separates the Archaean and Proterozoic rocks to the south and north, respectively. Gold mineralisation occurs in pinkish, K feldspar-quartz veins, quartz veins, and altered wall rock, and is localised by NE and NNE trending, west-dipping shear zones. The individual gold-bearing veins may be as much as a few kms long, continue to a depth of 600 m and average 3 m in width. The K feldspar-quartz and the quartz veins contain pyrite, calaverite, galena, chalcopyrite, gold and abundant hematite, although the associated base metal levels are generally low. Less voluminous mineralisation continues into the Archaean country rocks.
A selection of the main deposit may be summarised as follows (after Hart et al., 2002, except as otherwise cited):
Dongping is part of the Zhangjiakou District, in the Daqingshan Mountains Gold Province - see the separate record. Donping is 140 km northwest of Beijing.
Xiaoyinpan or Zhangjaikou, which is 17 km SW of Dongping and 35 km NE of Zhangjaikou city in northern Hebei province. Mineralisation is hosted by a regionally almost flat lying suite of Archaean amphibolite and granulite facies metabasalt and metasedimentary rocks. The only intrusive rocks in the deposit area are dolerite and lamprophyre sills, and felsic porphyry dykes, although a probable Yanshanian high-K calc-alkaline granite outcrops 3.5 km from the deposit. Jurassic volcanic rocks are regionally extensive. The most prominent local structure in the deposit area is the NE to NNE striking Huangqi–Wulong fault, although gold mineralisation is related to cross-cutting NW trending faults. The mineralised veins have no apparent spatial relationship to the dykes, whilst mapping suggests the distal high-K granite, and the proximal dykes, post-date mineralisation. Some 58 quartz veins, which are foliation parallel, or stacked 5 to 15°NE-dipping, are distributed over a 9 km2 area. The lodes are white quartz and quartz-alkali feldspar veins and lenses averaging ~2 m in thickness, although locally these may be as much as 10 m thick, with average grades of 9.7 g/t Au. Local breccia zones carry up to 20 g/t Au over widths to 2.5 m. The largest orebody (#16) hosts ~85% of the total resource in the deposit. Gold occurs in its free-milling native form or as electrum, as inclusions within pyrite or quartz, or intergrown with telluride minerals. Other minerals in the veining minerals include pyrite, galena, chalcopyrite, sphalerite, native gold, and tellurides. The ore contains up to 8.4 wt.% K, 5.6 wt.% Pb, 0.1 wt.% Mo and 81 ppm Te (Hart and Goldfarb, unpublished data). The hanging-wall zone has undergone alkali-feldspar alteration, whilst the footwall is cut by a north vergent fault. The lodes are locally offset along NW-striking high angle normal and reverse faults. Return to Top
Zhongshangou, which is ~25 km west of the Dongping deposit in the Zhangjiakou district and hosts a small gold resource in the western part of the 50 x 10 km, east-west elongated, Shuiquangou alkaline complex, close to a small hornblende monzo-syenite stock (Nie and Wu 1995). The deposit comprises a 0.5 to 1.0 m wide, north- to NE striking, moderately- to steeply-west-dipping quartz vein that is continuous over a strike length of almost 2 km. Ore style and The vein mineralogy and ore style are similar to that described at Dongping, although less extensive. The lode contains a few percent pyrite with minor galena, chalcopyrite, bismuthinite and gold-bearing telluride minerals. The quartz veins are dominantly massive, although locally brecciated or 'ribboned', and overprinted by late vuggy, chalcedonic or drusy quartz. Grades average 3 to 6 g/t Au and, and although veins narrow with depth, grades apparently increase to ~16 g/t at depths of 80 to 160 m. The veins are sandwiched by wall rock that is pervasively flooded by alkali feldspar and silica, locally over widths exceeding that of the vein. Distal alteration phases include sericite, chlorite and epidote. Return to Top
Zhangquanzhuang is located in the Zhangjiakou district ~25 km SW of Dongping and ~30 km south of the broad, east-west trending trans-lithospheric Shangyi-Chongli-Chicheng fault. It is hosted in metamorphic rocks, predominated plagioclase-amphibole gneiss with minor granulite and migmatite (Yin and Shi, 1994) of the Archaean Sanggan Group. NW trending dolerite and diorite dykes with widths of 0.5 to 2 m are the principal igneous rocks in the district. Gold mineralisation at Zhangquanzhuang was controlled by north-south and NW-SE striking faults, and mostly occurs as auriferous quartz veins with lesser disseminated ores. More than 50 auriferous quartz lenses or veins are known at the deposit. These average 1.2 m in thickness of and dip at 60 to 80°NE. Some ore veins have similar attitudes to coexisting diorite dykes. Gold reserve is predominantly contained in orebodies quartz-11 and quartz-12 with grades of from 1.17 to 3.63 g/t Au. The principal ore minerals are pyrite, galena, sphalerite, chalcopyrite and tetrahedrite in a gangue that includes quartz, K feldspar, sericite and calcite. Wall rock alteration includes assemblages that include silica, sericite, chlorite and carbonate. The bulk of the gold occurs as native gold and electrum. The former is mostly contained within pyrite and along fractures in pyrite grains, while electrum coexists with galena, sphalerite and chalcopyrite. Detailed field observations, cross-cutting relationships and microscopic observations of mineral paragenesis, have identified four stages of mineralisation. Stage I is characterised by K feldspar-quartz veins containing minor coarse-grained pyrite. Stage II contains thick, milky to smoky quartz veins that carry widely distributed cubic, coarse-grained pyrite. Stage III veins, which cut those of stage II and are dominated by polymetallic quartz-sulphide veins or veinlets containing pyrite, chalcopyrite, galena and sphalerite. Pyrite in this stage is euhedral to anhedral with much finer grain than that in stage II. Native gold occurs within pyrite and in fractures in pyrite, although electrum precipitated in this stage accounts for a large percentage of the gold mineralisation. This stage represents the major gold event. Stage IV mainly consists of calcite veins with minor pyrite, with little gold mineralisation. This summary is based on Zhen et al. (2020). Return to Top
Dabaiyang is located in the Zhangjiakou district, ~6 km south of Dongping. It is a medium-sized gold deposit, with reserves of 11 t both of Au and Te, hosted within the Huajiaying and Jiangouhe Formations of the Archaean Sanggan Group, and is ~20 km south of the broad, east-west trending trans-lithospheric Shangyi-Chongli-Chicheng fault. The Sanggan Group is dominated by plagiogneiss, migmatite, amphibolites, granulite, leptites and magnetite-quartzite. Igneous rocks in the surrounding district are predominantly NW-SE trending, 1 to 2 m wide, mafic and felsic dykes, including dolerite, diorite and pegmatite.
The deposit lies within a NNW-SSE trending anticlinorium, cut by NW, north-south and EW striking faults, the first two of which are the dominant ore-controlling structures, commonly offsetting strata on fold inverted limbs, indicating that faulting postdated the anticlinorium. There are >5 auriferous quartz veins that make up the deposit. These can be grouped into two types, i). milky, flat-dipping quartz veins with disseminated sulphides, low gold grades, and miarolitic cavities containing in-growing coarse quartz crystals; striking at 250 to 265° and dipping at 20 to 30°; and ii). grey, steeply-dipping veins that have large amounts of sulphides, high, up to 154 g/t Au grades and strike at 225 to 245° with dips of 50 to 70°. Within this set of veins and enclosing country rock, some 28 orebodies have been outlined, comprising auriferous quartz veins and disseminated ores. Each measures from 1 to 10 min thickness with grades averaging from 1 to 40 g/t Au, and Au:Te ratios of ~1:1. Auriferous quartz veins are tens of cm to a few metres in thickness, of the two types and characteristics described above. The disseminated ores have undergone intense silicification and K feldspar alteration, and contain numerous sulphide veinlets. Metallic minerals are dominantly hematite, magnetite, pyrite, chalcopyrite, galena, sphalerite, bornite, tetradymite, tellurobismuthite, altaite, hessite, native gold and electrum, accompanied by K feldspar, dolomite, calcite and fluorite. Hydrothermal alteration assemblages in the wallrock mainly includes K feldspar, silica, chlorite and sericite.
Four mineralising stages have been identified: Stage I is characterised by veins composed of milky quartz, reddish K feldspar and coarse-grained pyrite, accompanied by magnetite and hematite; Stage II, which is mainly quartz-pyrite veins with native gold, and rare chalcopyrite and galena. Pyrite is finer than in Stage I. This is an important gold mineralising stage; Stage III, dominated by polymetallic sulphide-quartz veins. The polymetallic sulphides comprise pyrite, chalcopyrite, bornite, galena and sphalerite, occurring as veins or veinlets. Pyrite is euhedral to anhedral and much finer than in Stage II. Tellurides, which include petzite, hessite, altaite, tetradymite and tellurobismuthite, are mostly precipitated during this stage. Native gold occurs in pyrite, especially it its fractures, while electrum coexists with galena, sphalerite and chalcopyrite. Stage III is the most important gold mineralising stage; Stage IV is predominantly composed of calcite veins and quartz veinlets and contains no gold or sulphides. This summary is based on Wang et al. (2021). Return to Top
Honghuagou and Lianhuashan are two adjacent deposits located ~40 km WSW of Chifeng in Inner Mongolia. Honghuagou was mined in the Qing Dynasty (i.e., 1636 to 1912 AD) and in recent times until 1958, before reopening in the 1970s. The deposit is characterised by high grade but low tonnage, NE-trending veins exposed in a window of Archaean plagioclase-hornblende gneiss, surrounded by Jurassic strata and Tertiary basalt cover. Associated intrusive rocks include diorite and granite (Nie 1997). Around 90 gold-bearing quartz veins are distributed over a 30 km2 north to NW-trending belt, which is subdivided into four zones. The largest veins trend NE and east and cut the metamorphic foliation. They vary in width from 0.2 to 2.0 m, averaging 0.8 m, are typically 70 to 200 m in length, and have been mined to 420 m downdip with no change of the average gold grade of ~6 g/t Au. The veins also include sphalerite, bornite and argentite, with gold occurring in its native form and as electrum (Nie 1997). The ore zones are cut by late faults and locally by a fine grained granite dyke. Apart from faint chlorite and local calcite veinlets, alteration is typically weak. Amethyst is found as vug infilling of veins. Gold-bearing veins with associated quartz porphyry and alkali-feldspar granite dykes have been dated at 180 Ma (Rb-Sr).
The adjacent and more northerly Lianhuashan deposit has a similar geological setting, but is cut by a swarm of northtrending mafic dykes. It contains high grades that average 18 g/t, locally up to 300 g/t Au, particularly at shallower depths, and a very low Ag/Au ratio. The gold grade is proportional to pyrite content which is accompanied by minor chalcopyrite and rare molybdenite, for a total sulphide content that rarely exceeds 5%. Most of the sulphide minerals occur in late veinlets that cut or replace earlier and brecciated quartz. Return to Top
The Zhuanshanzi gold deposit is located in Inner Mongolia, ~50 km east of Chifeng City. It lies in the eastern part of the Xingmeng orogenic belt, north of the Chifeng‐Kaiyuan translithospheric fracture of Inner Mongolia, and on the south side of the Inner Mongolia Variscan fold system. The principal stratigraphic units in the district surrounding the deposit include the Archaean Wulashan Formation composed of gneiss complexes and metamorphic supracrustal rocks; the Late Carboniferous Jiujuzi Group sandstone and slate, the Early Jurassic Beipiao shale and sandstone, and the early Cretaceous Yixian Formation volcanic rocks. The latter volcanic sequence is widely distributed. All are overlain by Quaternary cover. Regional magmatic activity was predominantly of Palaeozoic and Mesozoic age, with Late Palaeozoic granitoids, mainly a porphyritic biotite granite batholith, extensively developed in the south in the late Hercynian (Zhang, 1990). The Triassic to Early Cretaceous intrusions included diorite, granodiorite, granite and granite porphyry. These granitoid complexes mostly formed during the Yanshan period (125 to 132, 156 and 173 Ma; Wang et al., 1989; Miao et al., 2003;) and between 207 to 220 and 245 Ma (Sun et al., 2016).
In the Zhuanshanzi deposit area, the principal exposed sequence is the Lower Permian Qingfengshan Formation, a suite of moderately acidic volcanic to volcaniclastic rocks, and the Suolun Formation, a sequence of marine carbonate-clastic rocks. Marble is a relatively favourable host, whilst mineralisation is poorly developed in the slate and weak in diorite and granite porphyry. The late Hercynian diorite and Yanshan granitoids are the two principal intrusive rocks in the deposit area and are interpreted to be closely related to gold mineralisation (Liu and Jin, 1991; Yan et al., 1997) although other authors interpret the Yanshanian granitoids as the main associate of gold mineralisation (Wang and Zhang, 1995; Xu, 1995; Wang, 2014). Economic mineralisation mostly occurs east of the NE‐NNE trending Heishui‐Lianhuashan fault.
More than 80 clustered, banded quartz veins and 'altered tectonic rock‐type' veins make up the Zhuanshanzi gold deposit, along with calcite veins. The veining is strictly controlled by the NW shear/faulting. There are 7 veins with a length of >1000 m, with an average length of 1557 m. The remainder are usually 20 to 580 m in length, with an average length of 193 m. Individual veins extend from 40 to 360 m down dip and vary from 0.1 to 1 m in width, with most <0.3 m. The principal metallic minerals are pyrite, galena, chalcopyrite and sphalerite, and the main gangue minerals are quartz and calcite.
Four mineralising stages have been recognised. The first stage is milky quartz with minor coarse‐grained cubes of pyrite that filled and metasomatised along the host structures/fissures. These only contain a very small amount of gold. The second stage, also involves quartz + pyrite, filling and metasomatising along fracture zones and fissures in the outer sections of the previous milky quartz veins, or as veinlets within pre-existing zones of structurally controlled disseminated mineralisation. Minor galena occurs in symbiosis with pyrite. This was an important stage of ore deposition. The third stage involves quartz + polymetallic sulphides, including large amounts of pyrite, galena, sphalerite and chalcopyrite, and represents the main ore deposition stage. The fourth stage quartz + calcite + pyrite, comprises separate calcite or quartz-calcite veins with only minor quartz. This stage involves copias coarse‐grained pyrite, along with a small amount of galena and sphalerite. The surrounding rock is mainly silicified, sericitised and chloritised. Return to Top
Paishanlou is located ~22 km SE of Fuxin City in Liaoning Province and ~200 km ESE of Chifeng. The deposit was discovered in 1989 and open-pit mining had begun by 1993. The deposit is hosted in Neoarchaean metamorphic rocks of the Jianping Group, and is structurally controlled by two sets of ductile shear zones (Zhang et al., 2005). The dominant unit is the Dayingzi Formation of the Jianping Group, structurally and unconformably overlain by the Mesoproterozoic Changchengian System composed of predominantly relatively unmetamorphosed marine clastic and carbonate platformal successions. These are, in turn, overlain by extensive Cretaceous sedimentary sequences. The older rocks are intruded by Neoarchaean ~2.5 Ga syntectonic granites, as well as Early and Late Palaeozoic granites, Jurassic diorite and Lower Cretaceous monzonite, syenogranite and granite with equivalent extrusive dacite (Ni et al., 2014). The Jianping Group comprises 2.6 to 2.5 Ga tonalitic-trondhjemitic-granodioritic (TTG) gneisses, as minor mafic to felsic volcanic and sedimentary supracrustal rocks metamorphosed to upper greenschist to amphibolite facies (Wang et al., 1996; Luo and Zhao, 1997). The available isotopic data indicate a regional metamorphic age of ~2.5 Ma in this area (Luo and Zhao, 1997; Kröner et al., 1998), consistent with the time of the last regional metamorphic event in the Eastern and Western Blocks of the NCC (Zhao et al., 2001). The Mesozoic granitic intrusions and dykes that are common throughout the deposit area show little sign of mineralisation. The largest of these, the Dashitougou granitoid, crops out to the north of the deposit. It is a flesh pink biotite monzogranite, with a coarse-grained to porphyritic texture and massive structure, composed of plagioclase, K feldspar, quartz, biotite and minor hornblende, and has an age of 124±2 Ma (SHRIMP U-Pb zircon; Luo et al., 2001). Numerous dykes with variable degrees of deformation are spatially associated with gold lodes, and include a 126 to 124 Ma diorite-porphyry; 124±1 Ma granite-porphyry (SHRIMP U-Pb zircon ages; Luo Luo et al., 2001) and minor lamprophyre.
Gold mineralisation is closely associated with intense hydrothermal alteration along the ductile shear zones, with a typical greenschist facies alteration assemblage of sericite-chlorite-calcite-biotite-quartz and a distinct alteration zoning from ore to surrounding wall rock of i). inner pyrite-sericite containing ankerite, calcite, siderite, sericite, pyrite, green biotite over widths of 20–80 m, ii). middle carbonate with widths of 100 to 200 m, characterised by ankerite, calcite, siderite, brown biotite, chlorite, green biotite and epidote and iii). outer 250 to 460 m halo of epidote-biotite-chlorite.
Gold mineralisation is spatially confined to structural intersections or along the major east-west to ENE-WSW trending shear zones and occurs over a strike length of >1000 m, widths varying from 20 to 80 m, and a down-dip extent of >1000 m. Gold orebodies occur mainly as disseminations or network veinlets, localised in the inner pyrite-sericite zone. Some 35 orebodies have been delineated, of which the T1, T4 and T5 are the largest. T1 comprises a number of continuous shoots that are conformable with the inner alteration zone and have a stratabound form. Overall it strikes east-west and dips at 35 to 55°N, with a length of 600 m and a thickness of 2 to 20 m (averaging 7 m), a down-dip extent of 100 to 370 m. The mean grade is 4.44 g/t with maximum of 24.72 g/t Au. The ores are divided into two varieties, i). light ores that occur in quartzo-feldspathic gneiss that is characterised by a mineral assemblage of feldspar, quartz, carbonate and pyrite, and ii). dark ores mainly within biotite-plagioclase gneiss, typified a mineral assemblage that includes plagioclase, biotite and pyrite. The principal ore minerals include pyrite, chalcopyrite and pyrrhotite, with minor ilmenite, galena, sphalerite, chalcocite and millerite. Gold predominantly occurs in its native form with trace electrum and calaverite. Gangue minerals are variably distributed with different ore types, but characteristically include quartz, feldspar, plagioclase, carbonate, biotite, sericite and chlorite in both ore types.
Fluid inclusion petrography and microthermometric data suggest the ore was deposited at 1.4 to 1.9 kbar and 322 to 417°C, whilst isotopic data implies it involved mixing of deep-seated magmatic and shallower meteoric water. Ar/Ar plateau age of 126.6±1.1 Ma for biotite from the NNE ductile shear zone suggest a temporal link between Au mineralisation, magmatism and deformation at the Paishanlou deposit. The concordance of the biotite age with other well-constrained mineralisation ages for the deposit, and the intrusion age of the granite, suggests that Au mineralisation was essentially contemporaneous with late Mesozoic granitic magmatism and the second stage of mylonitisation (Zhang et al., 2005). Quartz fabrics indicate three periods of ductile shear events developed in the Paishanlou gold deposits and the east-west to ENE-WSW and NE-SW to NNE-SSW striking ductile shear zones were formed during each event (Ni et al., 2014). The the east-west to ENE-WSW set have undergone dextral oblique
reverse shearing, whilst the NE-SW to NNE-SSW structures show evidence of sinistral strike-slip and extensional shearing (Liu et al., 1996; Wang et al., 1996; Zhang et al., 2002). The east-west Paishanlou-Majiahuang ductile shear zone is the western part of a regional east-west trending linear structural zone that is widely distributed in the western Liaoning. It dips at 30 to 50°N and has a length of 5 to 6 km, with widths ranging from 1 to 2 km containing higher-strain sub-zones intercalated with the lower-strain domains. The higher-strain subzones have been strongly fractured and sheared, varying from proto-mylonite and mylonite to ultramylonite (Zhang et al., 2005). The enclosing lower-strain domains are mainly less-deformed metamorphic rocks, such as fractured gneisses, amphibolites and protomylonites. The cross-cutting NNE to NE Jianshangou-Paishoulou Ductile Shear Zone exhibits two generations of superposed lineations. The earlier, 30 to 40° NNW-plunging mineral lineation is defined by biotite, actinolite, quartz and feldspar and has 'a' type folds, S-C fabrics, asymmetric rotated porphyroclasts and boudins, which consistently indicate a top-to-SE oblique thrusting sense of shear (Li and Han, 1995; Wang et al., 1996; Luo and Zhao, 1997; Zhang et al., 2002). These are overprinted by a penetrative, gently to moderately NE-plunging mineral lineation, mainly defined by small sericite and strongly stretched quartz. S-C fabrics and other shear sense indicators suggest a consistent sinistral strike-slip and extensional ductile shearing (Li and Han, 1995; Wang et al., 1996; Luo and Zhao, 1997; Zhang et al., 2002). Return to Top
Jinchanggouliang, is located in the southern Inner Mongolia Autonomous Region whilst Erdaogou and Xiaochanggao, are in western Liaoning Province. These deposits have been mined for more than 100 years and are among the largest gold producers in northern China with a combined historic output of ~25 t and resources in 2002 of ~50 t Au. The deposits lie within the east-west trending Liaoxi Uplift (or Nulu'erhu uplift or anticline), ~80 km south of the northernmost margin of the North China Craton. The geology of the district is dominated by Archaean plagioclase-hornblende gneiss and amphibolite of the Jianping Group, intruded by numerous late Palaeozoic and Mesozoic granitoids, and overlain by extensive subaerial volcanic rocks dated at ~129 Ma (Mortensen in Hunt and Roddick 1992).
Jinchanggouliang and a number of other deposits surround the 6 km2 Xiduimiangou stock and a large NE trending Variscan quartz monzonite batholith (Poulsen et al., 1990; Nie 1997). This stock is zoned with a massive, coarse-grained to porphyritic granitic core, containing minor porphyry-style copper and molybdenum mineralisation (Nie 1997), and a finer-grained equigranular, granodiorite outer phase (Poulsen et al., 1990). The stock is surrounded by district-scale zoning, comprising an inner chalcopyrite-rich zone and peripheral galena-sphalerite. The core of the stock has been dated at 135 Ma (K-Ar alkali feldspar), the granodioritic border facies at 126 Ma (U-Pb zircon) whilst the porphyritic granite is 122 Ma (K-Ar). The older, apparently Variscan, quartz monzonite batholith returns an age 235 Ma (K-Ar; Li 1988 in Hart et al., 2002).
The Jinchanggouliang deposit comprises ~70 x north to NW striking, steeply-dipping, quartz veins that carry 5 to 20% sulphides, hosted within sinuous, gouge filled faults cutting Archaean gneiss and Mesozoic dykes (Nie 1997) above a north-dipping fault. Six of the orebodies range from 95 to 625 m in length with thicknesses of 0.2 to 1.5 m and down-dip extents to 1000 m. Grades average 10 to 12 g/t Au (Nie 1997), with no change with depth. Gold occurs in its native form as inclusions in pyrite and quartz and as electrum. The dominant sulphide is pyrite with lesser galena, sphalerite and chalcopyrite, and rare tetrahedrite, covellite and bornite. Silver:gold ratios are ~3 to 5 making the district the only such silver-rich gold deposit of significance along the northern margin of the North China Craton. There is also a consistent enrichment of As, Hg, and Sb values (Goldfarb and Hart, unpublished data), with realgar and orpiment being reported in the ore (Poulsen et al., 1990). Alteration dominantly occurs as phyllic selvages to veins, with widespread chloritic alteration in the Archaean country rocks. The Erdaogou deposit (Lin et al., 1993) is hosted by Jurassic volcanic rocks and is spatially associated with diorite dykes. Return to Top
Jinchangyu is ~180 km ENE of Beijing and had the largest gold resource (in 2002) in eastern Hebei province in a region that has been intermittently mined since the Tang Dynasty (i.e., 600 to 900 AD) with considerable production also during the Qing Dynasty (i.e., 1636 to 1912 AD). The deposits of the district are all located within Precambrian uplifts of the east-west trending Yanshan Fold Belt, mostly hosted by Archaean basement granulite facies rocks of the Qianxi Group that is dominated by migmatitic amphibolite of the lower Shangchuang and upper Badaohe Formations. The nearest intrusion, the Qingshankou Complex, is 3 km west of Jinchangyu, and while dominated by biotite granite, ranges from quartz diorite to muscovite-bearing alkali feldspar granite (Trumbull et al., 1992) with local garnetiferous orbicules and cross cutting pink granite porphyry dykes (Poulsen and Mortensen 1993). Pre-ore albitic felsic dykes parallel the ore zone and although interpreted to be derived from the Qingshankou Complex (Trumbull et al., 1992), have since been dated at >1.5 billion years older (SHRIMP U-Pb zircon; Qiu, in Hart et al., 2002) than the granitic intrusions of the complex which are dated at ~197 Ma (SHRIMP U-Pb zircon; Qiu, in Hart et al., 2002) and 196 Ma (K-Ar; Yu and Jia, 1989). The ore zone cuts a set of lamprophyre dykes.
The Jinchangyu deposit and associated lodes are developed over a 6 km interval of a 15 km, NNE-trending, anastomosing, NW-dipping shear zone that is dominantly ductile deformation, but includes brittle tensional elements. The northern (Xiaying and Heishiyu), central (Jinchangyu) and southern (Sanjiayu) sections of the deposit are all hosted by Archaean rocks. Undeformed dykes in the shear zone are cut by mineralisation, indicating that the ore is post-kinematic. Whilst the host shear zone is dominated by sericite-chlorite schist, overprinting alteration flanking the veins comprises a proximal sericite-quartz zone and a more-distal peripheral assemblage of epidote-chlorite and local carbonate (Poulsen and Mortensen 1993).
Veins are dominantly steeply dipping, although several subhorizontal zones of quartz veins cut the metamorphic fabric. Brittle post-ore faults in the shear zone have predominantly undergone reverse dip-slip displacement, with local strike-slip motion. The lodes are characteristically quartz±albite veins containing as much as 10 vol.% sulphide minerals. They vary from 90 to 300 m in length, 1 to 6 m in width, and have been traced to at least 500 m down-dip. Most of the gold is associated with pyrite, and less often with chalcopyrite, bornite, sphalerite and molybdenite, although the ore typically contains less than a few hundred ppm base metals. Rare tellurides are recorded. Gold occurs in its free form with an average fineness of 919, as electrum, and as 5 to 20 µm inclusions, rims and fracture infilling of pyrite, and, less commonly, in quartz with tellurium as calaverite. Return to Top
Niuxinshan, which is ~10 km east of the Jinchangyu deposit, occurs as >20 quartz veins that strike NE (Trumbull et al., 1992). Unlike at Jinchangyu, these auriferous veins cut Middle Jurassic, ~174 Ma granite as well as the Archaean amphibolites. Individual veins are up to 1000 m in length and up to 2 m in width, persisting to depths of 500 m, andare generally thicker in amphibolite hosts as compared to the granite (Yao et al., 1999). A four-stage paragenesis includes successive quartz-feldspar, quartz-pyrite, quartz-base metal sulphide and quartz-carbonate phases, with gold mainly associated with sulphide minerals in the third phase, and grades averaging 15 to 20 g/t Au (Trumbull et al., 1992; Yao et al., 1999). Return to Top
Yuerya, Liu et al., (2106) which was discovered in 1887, and is located ~25 km SE of the Kuancheng Manchu Nationality Autonomous County in south eastern Hebei Province. Mineralisation is hosted within in 175 to 174 Ma (Liu et al., 2001) Yuerya granite and its contact zone with strata of the Mesoproterozoic Changcheng System (Jia et al., 2104) and is controlled by NE and NNE trending fault sets. Mineralisation associated alteration is characterised by an assemblage that includes pyrite, quartz, sericite, albite and carbonate, and was emplaced in 4 stages Four stages, in chronological order: i). quartz and medium- to coarse-grained pyrite; ii). quartz, fine-grained pyrite and gold; iii). quartz, polymetallic sulphide, tellurobismuthite and gold; and iv). quartz, pyrite and carbonate. The bulk of the gold was deposited during the second and third stages from low salinity mesothermal fluids that were relatively rich in H2O, CO2, K+, Ca++, Cl and S. Isotope ratios of H, O abd S indicate a magmatic fluid source, whilst Pb isotope data indicate that the Au originated from the mantle and lower crustal materials. Geochronological data indicate that the Yuerya gold mineralisation was emplaced at 169.8 Ma (Re-Os; Chen et al., 2014) a little younger than the age of the Yuerya granite (Liu et al., 2016). Return to Top
Baizhangzi is located within the northern part of the Eastern Hebei to Western Liaoning Gold Metallogenic Belt, and was discovered in 1979. The country rock in the deposit area is mainly composed of Neoarchaean and Meso- to Neoproterozoic metamorphic basement, overlain by lesser Mesozoic and Cenozoic volcano-sedimentary strata and intruded by Archaean and Mesozoic granitoids (Ge, 1989; Song, 1999). Tens of gold deposits occur as auriferous quartz-sulphide veins or as disseminated Au-bearing pyrite within the altered granitoids (Wang and Xuan, 2008). These deposits are largely hosted by the Neoarchaean Dantanzi Group and Proterozoic strata, whilst several are within Mesozoic granitoids (Mei, 1997). The Dantanzi Group is the dominant unit in the area, and is composed of metamorphosed sequences that range from fine-grained granulite-facies biotite-plagioclase rocks, through magnetite-quartzite and amphibolite to greenschist facies rocks (Li et al., 1996; Qu, Li and Liu, 2012). The overlying Meso- to Neoproterozoic sequences are represented by the: i). Changchengian System, which is dominated by littoral to neritic felsic sandstone, carbonaceous shale and dolostone; ii). Jixianian System, a neritic carbonate sequence and iii). Qingbaikouan System, littoral clastic sandstone and shale. Both the Dantanzi Group and Proterozoic units, mainly sandstone, shale and dolomite, host gold mineralisation (Xiong et al., 2015).
Igneous rocks in Eastern Hebei are characterised by Mesozoic granitoids, mafic to felsic dykes and Archaean diorite. Mesozoic granitoids intruded Proterozoic sedimentary rocks along regional faults, mostly as stocks although there are also several complex batholithic intrusions (Luo et al., 2001; 2003). Batholithic intrusions include the NE-SW elongated, 60 x 10 to 20 km composite Dushan-Dashizhuzi Complex, which is composed of monzonitic granite, biotite monzonitic granite and granodiorite, dated at 223 Ma in the Upper Treiassic (SHRIMP zircon U-Pb; Luo et al., 2003). A majority of the stocks are calc-alkaline granites and include important gold host rock (Zhu, Wu and Cui, 1999). At shallow levels, mineralisation is predominate hosted by sedimentary rocks, as detailed above, and by Mesozoic granite at greater depths (Xiong et al., 2015).
The auriferous quartz-sulphide veins are restricted to subsidiary NNE-, NE- and NW- trending faults in the hanging wall of a regional NNE-trending F2 fault, all of which are intruded by diorite and granite dykes. The F2 fault is ~5 km in length, dips at 55 to 60°SE, and forms the western boundary to gold mineralisation. It is one of a set of subparallel, NNE-trending regional faults within the Yanshan District and was active during multiple episodes. The subsidiary NE- and NW-trending faults appear to be compressive and extensional respectively. Both the F2 and subsidiary NNE faults are sinistral reverse structures. The subsidiary faults all displace both the Changchengian System and the granite intrusions. The NE- and NW- trending subsidiary faults are restricted to the granite intrusion along the middle and southern parts of the F2 fault. The NNE-trending, Au-bearing faults are en echelon, wave-like structures dipping at 45 to 70°SE. They strike at an angle of 7 to 17° to, and dip slightly steeper than, the F2 fault (Xiong et al., 2015).
The disseminated Au-bearing sulphide mineralisation is largely restricted to altered granites, and is characterised by silica, pyrite and kaolin alteration, with subordinate chalcopyrite, galena and molybdenite mineralisation. They are located in the footwall/inner contact zone of the granite, and are also distributed along the F2 fault. The granite at Baizhangzi is dominantly a calc-alkaline intrusion occurring as narrow dykes at shallow levels and as a stock at greater depths, elongated parallel to, and ~1.5 km NW of, the main Dashizhuzi Complex intrusion (Bai, 1995; Xiong et al., 2015; Xiong et al., 2018). Return to Top
Deposit Size and Grade
Gold endowments include (mostly after Yang et al., 2003):
Dongping - >100 t Au with an average grade of 6 g/t Au;
Xiaoyingpian - ~68 t Au with an average grade of 9.7 g/t Au - production + 'reserves', 2002 (Hart et al., 2002);
Honghuagou - >23 t Au with an average grade of 15.8 g/t Au;
Paishanlou - 40 t Au with an average grade of 4 g/t Au;
Erdaogou - >20 t of Au at grades of 6 to 19 g/t Au;
Jinchangouliang - 50 t Au with an average grade of 12 g/t Au;
Jinchangyu - 90 t Au with an average grade of 2 g/t Au;
Yuerya - 65t Au with an average grade of 2.3 g/t Au;
Baizhangzi - >20 t Au with an average grade of 8.2 g/t Au and 25.7 g/t Ag (Xiong et al., 2015);
Niuxinshan - >20 t Au with an average grade of 20 g/t Au;
Zhuanshanzi - >18 t Au with an average grade of 10 g/t Au (Sun et al., 2018).
gold deposit is located in Inner Mongolia, approximately 50 km east of Chifeng city and in the Aohanqi territory. The geographical coordinates are E: 119°35′, N: 42°18′ (Fig. 1). It is composed of the Zhuanshanzi, Liangbanshan, and Luofengmao mining areas. Presently, hundreds of gold veins have been found. The total amount of gold metal has been verified and controlled by 18 t, with an average grade of 10 g t−1
The most recent source geological information used to prepare this decription was dated: 2021.
Record last updated: 27/2/2021
This description is a summary from published sources, the chief of which are listed below.
© Copyright Porter GeoConsultancy Pty Ltd. Unauthorised copying, reproduction, storage or dissemination prohibited.
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Selected References:
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Fan, G.-H., Li, J.-W., Deng, X.-D., Gao, W.-S. and Li, S.-Y., 2021 - Age and Origin of the Dongping Au-Te Deposit in the North China Craton Revisited: Evidence from Paragenesis, Geochemistry, and In Situ U-Pb Geochronology of Garnet: in Econ. Geol. v.116, pp. 963-985.
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Hart, C.J., Goldfarb, R.J., Qiu, Y., Snee, L., Miller, L.G. and Miller, M.L., 2002 - Gold deposits of the northern margin of the North China Craton: multiple late Paleozoic-Mesozoic mineralizing events: in Mineralium Deposita v.37, pp. 326-351.
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Li, H., Zhu, D.-P., Algeo, T.J., Li, M., Jiang, W.-C., Chen, S.F. and Elatikpo, S.M., 2023 - Pyrite trace element and S-Pb isotopic evidence for contrasting sources of metals and ligands during superimposed hydrothermal events in the Dongping gold deposit, North China: in Mineralium Deposita v.58, pp. 337-358.
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Liu, C., Nie, F. and Bagas, L., 2016 - Geology and ore genesis of the Yuerya gold deposit, eastern Hebei Province, China: in Ore Geology Reviews v.73, Part 2, pp. 270-283.
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Ni, J.-L., Liu, J.-L., Tang, X.-L., Ahao, C.-Q. and Zeng, Q.-D., 2014 - Evolution of the ductile shear zone of the Paishanlou gold deposits, western Liaoning, China: in Science China Earth Sciences, v.57, pp. 600-613.
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Sun, Z., Wang, Z., Yu, H., Wang, C., Liu, G. and Bai, X., 2018 - Fluid Inclusions and C-H-O-S-Pb Isotopes: Implications for the Genesis of the Zhuanshanzi Gold Deposit on the Northern Margin of the North China Craton: in Resource Geology v.69, pp. 1-21.
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Wang, D., Zhen, S., Liu, J., Carranza, E.J.M., Wang, J., Zha, Z., Li. Y. and Bai, H., 2021 - Mineral paragenesis and hydrothermal evolution of the Dabaiyang tellurium-gold deposit, Hebei Province, China: Constraints from fluid inclusions, H-O-He-Ar isotopes, and physicochemical conditions: in Ore Geology Reviews v.130, 14p. doi.org/10.1016/j.oregeorev.2020.103904.
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Xiong, L., Wei, J.-H. and Shi, W.-J., 2015 - Structural and Lithological Controls on the Location of Orebodies in the Baizhangzi Lode Gold Deposit in Western Liaoning Province, China: in PACRIM 2015 Congress, Hong Kong, Cina, 18 to 21 March 2015, The Australasian Institute of Mining and Metallurgy, Proceedings, pp. 193-199.
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Xiong, L., Wei, J.-H., Shi, W.-J., Fu, L.-B., Li, H., Zhou, H., Chen, J.-J. and Chen, M.-T., 2018 - Geochronology, petrology and geochemistry of the Mesozoic Dashizhuzi granites and lamprophyre dykes in eastern Hebei - western Liaoning: implications for lithospheric evolution beneath the North China Craton: in Geological Magazine, Cambridge University Press, v.155, pp. 1542-1565.
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Yang, J.-H., Wu, F.-Y. and Wilde, S.A., 2003 - A review of the geodynamic setting of large-scale Late Mesozoic gold mineralization in the North China Craton: an association with lithospheric thinning: in Ore Geology Reviews v.23, pp. 125-152.
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Zeng, Q., Wang, Y., Yang, J., Guo, Y., Yu, B., Zhou, L. and Qiu, H., 2020 - Spatial-temporal distribution and tectonic setting of gold deposits in the Northern margin gold belt of the North China Craton: in International Geology Review doi.org/10.1080/00206814.2020.1737839 32p.
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Zhang, X.-H., Liu, Q., Ma, Y.-J. and Wang, H., 2005 - Geology, fluid inclusions, isotope geochemistry, and geochronology of the Paishanlou shear zone-hosted Gold Deposit, North China Craton: in Ore Geology Reviews v.26, pp. 325-348.
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Zhen, S., Wang, Q., Wang, D., Carranza, E.J.M., Liu, J., Pang, Z., Cheng, Z., Xue, J., Wang, J. and Zha, Z., 2020 - Genesis of the Zhangquanzhuang gold deposit in the northern margin of North China Craton: Constraints from deposit geology and ore isotope geochemistry: in Ore Geology Reviews v.122, 10p. doi.org/10.1016/j.oregeorev.2020.103511.
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Zhou, T., Goldfarb, R.J. and Phillips, G.N., 2002 - Tectonics and distribution of gold deposits in China - an overview: in Mineralium Deposita v.37, pp. 249-282.
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