幔枝构造是地幔热柱的第三级构造单元,是地幔热柱多级演化在岩石圈浅部的综合表现形式,是重要的成矿控矿构造.研究认为,燕山运动以来,华北东部地区进入了地幔热柱演化阶段,在众多成矿控矿因素中,区域性韧脆性和脆韧性剪切带以及区域性深断裂构造应是成矿作用的主导性因素,它们不仅是成矿流体的运移通道,而且往往成为重要的成矿储矿构造.地球在重力均衡作用和分异作用下,一直进行着物质的垂向分异和水平运动.重力分异作用使地球物质形成地核—地幔—地壳等结构分层,热力作用则使地球物质发生垂向上下运动.由于地球的核—幔界面是液态外核与塑性态下地幔之间存在的过渡(康氏面D")层,两者之间具有巨大的密度差、 压力差、 温度差、 速度差等,从而导致地球物质的热—冷物质循环,在洋壳离散区形成的岩浆上涌带和板块汇聚区形成的俯冲带,构成四维物质循环;陆壳上则形成地幔热柱—地幔冷柱间的物质交换.与此同时,深源含矿流体通过地幔热柱—地幔亚柱—幔枝构造—有利构造扩容带,迁移到幔枝构造的脆韧性—韧脆性主、 次级剪切带,侵入岩体的内、 外接触带,密集的构造裂隙带,各种脉岩与围岩的接触带等有利部位集聚成矿.华北东部是我国黄金成矿集中区,多个省份黄金地质找矿均取得了重大进展.金矿的形成过程可以概括为:强烈的岩浆—变质杂岩上涌(隆)—上部盖层向外拆离滑脱—断裂构造体系转制—幔枝构造逐渐形成—含矿流体沿断裂快速贯入—成矿物质冷却结晶,形成区域性大型—超大型金矿(区)带.本文仅选研究实例:区域性成矿集聚区—大兴安岭多金属矿的成矿控矿;典型金矿矿床解剖—中山沟金矿构造成矿控矿找矿断裂构造控矿分析—郭家岭幔枝构造及其成矿控矿.探讨成矿作用,总结成矿规律,归纳成矿模式,确定找矿方向,指导新一轮地质找矿.

In order to deeply study the migration regularity of element and preliminarily infer the fluid evolution during alteration processes in the Mujicun Cu (Mo) deposit, the authors tested and analyzed the samples which were respectively collected from the strongly silicified zone, the potassic zone, the quartz-sericitic zone and the propylitic zone in the ore-bearing diorite porphyrite body. Through calculation based on the formula by Grant, the authors made a tentative quantitative discussion on characteristics of the gains and losses of elements during their migration. The results demonstrate that mass migration of different elements show certain regularities within the range of mineralized alteration: (1) the initial hydrothermal fluid is rich in K and is poor in Na. Compared with least-altered rocks (the propylitic zones), the losses of Fe2O3, MgO, P2O5 and TiO2 turn into the gains in altered rocks from deep strongly silicified zone to shallow quartz-sericitic zone, with the generally opposite migration regularity of SiO2 and MnO, and FeO is depleted in the three alteration zones. (2) The migration regularity of rare earth elements is similar to that of Fe2O3 and some other components. The REE curves assume a rightly dipping REE pattern, indicating obvious fractionation between LREE and HREE, with the enrichment of LREE and the losses of HREE. (3) Cu and Mo are especially enriched in the quartz-sericitic zone and also relatively enriched in the potassic zone. These data suggest that the altitude of 400-500 m in the diorite porphyrite body is the main Cu and Mo enrichment area.

The Hadamengou Gold Deposit in Inner Mongolia is so far the largest gold deposit,with superlarge scale.The gold mineralization has no definite selectivity on lithology,however,it is mainly controlled by fold and fault structures.Ore-forming fluids are mainly originated from the deep source,and are accumulated within the favorable zones of tectonic expansion forming the ore-deposit.Research shows that,the mechanical property of the structural deformation in this area had been evolved from plastic to brittle since the beginning,and the scale of deformation is from small to large.Folding and shearing deformations were formed simultaneously or alternatively during the tectonism.There are four periods(or times)of intensive folding and shearing in this area,and the main ore-forming and ore-controlling structures are formed during these periods.During the first period,the rocks showed strong rheological property.So the foldings developed are characterized by low amplitude and small scale plastic rheomorphic folds.They are thickened in hinge zone and thinned in the limbs,even appeared a series of ptygmatic folds,and small scale ductile shear zones are developed.Second period of deformation formed the major regional fold which takes the Wulashan main peak antiform as a backbone forming east-west trending anticlinoria and synclinoria,and developing a series of brittle ductile shear zones in the overturned limbs of the major folds,they constitute the regional tectonically weak zones.In the third period developed the crossover superimposed fold,which makes the nearly E-Wtrending folds turned to be North-South snake-like bending,accompanying with low greenschist facies ductilebrittle shear zone,which provides the favorable space for the occurrence of ores formed by penetration and accumulation of the deep sourced ore-forming fluids and is the main ore-forming and ore-controlling structure.The fourth stages of tectonic deformation is mainly of regional uplift,together with the bending of the earlier folds the gold ore bodies formed in the depth are uplifted to the shallower part,and makes them easier to be found and exploited.In the present paper on the basis of research on the metallogenic and ore-controlling structures,the metallogeny of ore-deposits is discussed and the perspective of ore-prospecting is put forward.

The Mujicun copper (molybdenum)polymetallic orefield in the Taihang Mountains,is located in the secondary faulted basin developed in the upper block of detachment zone on the west side of the neck of the dumbbell shaped Laiyuan igneous complex,the northeastern pitching end of the Fuping mantle branch structure.It is composed of porphyry copper (molybdenum)deposit,skarn iron-copper deposit and hydrothermal vein lead-zinc-silver deposit in periphery, and become the most perspective large-scale copper (molybdenum ) polymetallic orefield in Hebei Province at present. Considering the study of ore-forming material sources is crucial for further understanding the metallogenesis of the deposit and the direction of ore-prospecting,authors tested and analyzed sulfur, lead,carbon,hydrogen,oxygen,silicon,and rhenium isotopic compositions in such minerals from the ore as chalcopyrite,galena,pyrite,molybdenite,magnetite,quartz and gypsum.The data showed that the major value ofδ34 S changes from - 3.5‰ to 3.2‰,with the average of 0.3‰;206 Pb/204 Pb from 15.566 0 to 17.072 0,with the average of 1 6.547 0;207 Pb/204 Pb from 15.031 0 to 15.523 0,with the average of 15.258 0;208 Pb/204 Pb from 36.292 0 to 37.375 0,with the average of 36.721 0;δ1 3 C from-2.94‰ to -2.18‰,with the average of -2.62‰;δ30 Si from -0.3 ‰ to 0.2 ‰,with the average of 0.0‰;w (Re)from 23.65 μg/g to 266.50 μg/g,with the average of 142.33 μg/g;δ1 8 OH2 O from-10.64‰ to 7.70‰,with the average of -1.47%,δD from -148.4‰ to -89.0‰,with the average of -1 13.7‰ which is less than that of the standard magmatic water.These isotopic data mentioned above show that the ore-forming materials were mainly derived from the deep source and the ore-forming solutions are mainly composed of magmatic water and partly of atmospheric water.

The northwest of Jiaodong peninsula is characterized by its greatest gold concentration area, enormous gold reserves and limited time interval（115±5Ma） of gold mineralization in China. Studies show that the east area of north China began its mantle plume evolution since the Yanshanian movement, and the Laiyang sub-mantle plume and its surrounding mantle branches such as those in Guojiadian, Aishan and Panshidian were formed in the mineralization concentration area of northwestern Jiaodong peninsula. With the development of mantle plume → sub-mantle plume → mantle branch → favorable expending structures, the deep-derived hydrothermal fluid moved up to the favorable places, such as brittle-ductile or ductile-brittle shearing zones, the internal and external contact zones of intrusions, dense fracturing zones and the contact zones between dikes and countryrocks, and concentrated into deposits. Then the gold mineralization concentration zones that are centralized on mantle branches were formed. This study takes Guojiadian mantle branch as an example to discuss their metallogenetism and conclude the metallogenetic mode.

The Mujicun copper(molybdenum) deposit is a large copper(molybdenum)-gold and silver polymetallic ore field in the northern Taihang Mountains,which is located in a secondary faulted basin in the upper wall of the detachment zone on the west of the Laiyuan complex rock body with a dumbbell shape,the northern section of Fuping mantle branch structure.This paper analyzes the rock-controlling function and ore-controlling model of the structures in this area based on the metallogenic geological background and latest exploration results.It is concluded that the deposit was controlled by diorite-porphyrite bodies,which intruded in the faulted basin,and its related fracture tectonic system as well as strong wall rock alteration zones.The Mujicun porphyry copper(molybdenum) deposits,skarn iron-copper deposits(such as Futuyu),and hydrothermal vein Lead-zinc-silver polymetallic deposits(such as He'ergou) jointly constituted a large polymetallic ore field with typical characteristics of serial mineralization.

Gongchangling iron deposit is in large size and discovered earlier with a long mining history.To depth ore gets rich.Structural analysis shows that the second mining district was exposed to,at least 4 deformation episodes.The first episode is small plastic flowing deformation of folds,the second episode regional inverted isoclinal folds,the third episode cross overprinting fold,the fourth regional uplift.The four episodic deformations were accompanied by ductile shear zone which is characterized by ductile shear zone-brittle-ductile zone-ductile-brittle zone-brittle fractural zone from early to late.The deformation shows a certain control on formation of the iron ore.

The role of He and Ar isotopes in tracing the source of ore fluids has aroused great attention of the broad masses of the geological researchers. On the basis of lots of test and measurement of He and Ar isotopes in sulfides from Au, Ag polymetallic ore deposits in northern China, statistics has been made on the published He and Ar isotope data from 27 gold deposits, 13 silver polymetallic ore deposits, 8 polymetallic ore deposits, 1 rare-earth deposit, 3 oceanic incrustations, 3 volcanic springs and their wall rocks and granites. The statistical results indicate that the 3He/4Ar (×10−6) values of the Au, Ag polymetallic ore deposits are within the range of 0.24–9.39, with an average of 3.34×10−6; the He/Ar values, 0.007–6.01,with an average of 2.37; the 40Ar/36Ar values, 265.75–2361, with an average of 699.0; the 4He/40Ar values, 0.0020–643.86, with an average of 5.85, the 3He/4Ar (×10−6) values of gneiss and granite surrounding the mining area, 0.001–1.79, with an average of 1.00×10−6, reflecting great differences in source. Mantle-source He in 48 Au, Ag polymetallic ore deposits accounts for 4.55%–83.06%, averaging 29.91%. It falls near the mantle-source region which can be seen in the He isotopic concentration diagram and the 3He/4He(R/Ra)-40Ar/36Ar plot. Studies suggested that the ore-forming materials for endogenic Au, Ag polymetallic ore deposits should be derived from the deep interior of the Earth, and with the multi-stage evolution of mantle plumes the deep-seated ore fluids would be transported from the deep interior of the Earth to the shallow levels. During this process the mixing of crust/mantle-source fluids would inevitably occur, therefore, the value range always lies between the mantle and the crust.

The Mujicun Cu (Mo) ore deposit at Laiyuan, Hebei Province, is a currently proven large-sized Cu (Mo) polymetallic ore deposit and it is located in the second-ordered fault depression basin of the ditachment belt on the hanging-wall on the western side at the juncture of the Laiyuan dumbell-shaped complex in the northern part of the Fuping mantle-branch structure. Metallogenesis is controlled by diorite porphyrite in intrusive relation with the fault depression basin and other relevant fault structure systems and intenstive wall-rock alteration zones. This study, in conjunction with the most recent exploration data, analyzed the geological background of metallogenesis of this deposit, summaried the geological characteristics of typical ore deposits, determined the alteration zonation of the deposit, investigated regional metallogenesis and the genesis of typical ore deposits, discussed the regional ore-forming and ore-controlling structures, and generalized the regional ore-controlling model and metallogenic model of the deposit. It is considered that the Mujicun porphry Cu (Mo) deposit, the Tieling, Futuyu, Xiaoligou and other skarn-type Fe-Cu deposits and the He’ergou hydrothermal-type Pb-Zn-Ag deposit jointly constitute a three-in-one polymetallic orefield, with the characteristics of typical metallogenic series.

The studies indicate that the metallogenic materials mainly comes from the core-mantle areas of the earth in the form of gaseous-gas-liquid mixed state-ore-bearing fluid.They migrated to the ductile-brattle zones,intruded internal and external contact zones of intrusives,contact zones between dykes and country rocks and formed mineral resources through mantle plumes to sub-mantle plumes and mantle branch structures,favorable tectonic extension zones.Ordered combination of ore fields,deposits and orebodyies(veins) of different deposit types have been formed as well.Therefore,tectonic ore-forming and ore-controlling should be paid more attention in order to guide the new round of geological prospecting and mineral resources evaluation.Cross cutting relation of Jiaojia fault and Sanshandao fracture in northwest Shandong Peninsula and its ore-controlling have been analyzed in this paper.

Northwest Shandong peninsula area is the largest gold ore concentration area in China.It has huge reserves,and ore-forming time is concentrated in 115±5Ma.It is show that since the Yanshan movement,eastern part of North China has come into the mantle plume evolution stage.Laiyang sub-mantle plume has been formed in northwest area,while Guojiadian,Aishan and Panshidian mantle branch structures have been formed in its peripheral areas.The ore-bearing fluid in deep-derived was migrated to favorable zones and formed gold resources,such as ductile-brattle or brattle-ductile zones,internal or external contact zones of intrusives,dense structural fractures,contact zones between dykes and country rocks through mantle plumes to sub-mantle plume and mantle branch structures,and formed gold ore concentrated area with mantle branch structure at the center.In this paper,setting Guojiadian mantle branch structure as an example,mineralization has been analyzed,and metallogenic model has been set up.

The solid mineral resources in mountain area and the petroleum in basin are two main areas of geological researches, with different emphasis and normally assigned to different department, so that interdisciplinary investigation is scarce to date. The Luxi uplift consists of Nikunshan-Muzishan, Mengshan, Culaishan-Xinfushan-Mengliangang and Taishan-Lushan-Yishan etc. spreading from south to north, furthermore, among these uplift there are distributed four neighboring fault depressions i.e. Siping, Wenmeng, Feicheng and Laiwu fault depressions. Between the fault depressions and the uplift developed the typical listric faults which control the Miocene dustpan-shaped sediments in the fault depressions. In the case of the Qikou depression, there are three subclasses of depressions as Qinan, Qibei and Banqiao with Nandagang and Beidagang buried-hill structure belt as the boundaries and taken on the dissymmetry form with the northern side deep and steep, the southern side shallow and nearly flat. The Qikou depression was faulted in the north and overlapped in the south. Comparative study of the sag and the structure of uplift and depression in the uplift area of Western Shandong becomes an urgent need. From the point of view of mantle branch, the authors propose that both the Luxi uplift and Qikou depression have the main structural features formed through coupling of mountain and basin.

The Jinchangyu ore deposit is a large-size gold deposit in eastern Hebei with mining history of more than half a century.In recent years,its resource reserves are constantly increasing.Which has aroused extensive attention among geologists.From the angle of ore-forming and ore-controlling action of the mantle branch structure,this paper briefly describes geological characteristics of the Jinchangyu gold deposit,with the emphasis placed on the source of the metallogenic material.The authors hold that the ore-forming materials were mainly derived from the boundary of the core – mantle and,through multiple evolution of mantle plume,they moved to the favorable structure and were deposited to form ore deposits.This paper emphatically discusses ore-forming and ore-controlling action of geological structure on the basis of achievements obtained in recent years.The prospecting directions in the depth and the periphery of the Jinchangyu gold deposit are pointed out.

Metallogenesis in the gold ore-concentrated zone of Northwest Shandong Peninsula is closely related to deep processes. The region in the eastern part of North China entered into the stage of mantle plume evolution during the Yanshanian movement, following the long-time stage of stable platform evolution during Paleozoic time. At that time, the ore-concentrated zone of Northwest Shandong Peninsula just entered into the development-evolution stage of the Laiyang sub-mantle plume and the Guojiadian mantle branch structure in its periphery. The core-mantle-source gold was present in the gas-liquid form, and it migrated through mantle plume→sub-mantle plume→mantle branch structure→favorable tectonic expansion zone to the favorable loci of the mantle branch structure, where gold was deposited as ores, thereafter constituting a series of large- to medium-sized gold deposits distributed around the Guojiadian mantle branch structure. This study also dealt with the Jiaojia fault as the main detachment (fault altered rock) belt on the northwestern margin of the mantle branch structure and also presented a basic cognition about the fact that the Sanshandao fault as the listric fault on the hanging wall of the detachment belt. Furthermore, on this basis, this study also pointed out the orientation for further ore prospecting in this region.

In recent years,the mineralization-concentrated regions with gold-silver polymetallic deposits in Mapeng area have been famous as superior ore-forming geological conditions in the whole middle segments of Taihang mountains soon.Twenty-five gold-silver polymetallic deposits(occurrences) have been successively discovered,most of them located around in Mapeng granitic intrusion.But currently eight mineral occurrences with exploiting value have been discovered,in which especially the Shihu gold deposit has become the only large ore deposit,so the regional metallogenic regularities and the metallogenic relevance in these deposits should be summarized in order to guide further ore-prospecting work.Through studying regional geological conditions and contrastively analyzing typical ore deposits with Shihu gold deposit on the southeast of Mapeng granitic intrusion and Beiyingxigou silver deposit on the southwest of Mapeng granitic intrusion,this paper finds the deposits(occurrences) surrounding the rock have the great analogues in regional structure,strata,magmatic activity,wall-rock alteration,lode features,etc.and they belong to yanshanian unified metallogenic series events.Based on this,we summarize the regional metallogenic regularities and the regional metallogenic model,and point out the regional prospecting direction.

In order to study the characteristics of ore-controlling structures and the evolution processes of tectonic stress field in the Hadamengou area,the regional joints,combined with deposit geological features and regional tectonic evolution were investigated.The results show that the ore formation was directly related to the potassic alteration in the foreland structure zone,which connected underlying pluton in the core part of the complex fold with the shallow joints,and acted as the major channel of fluid migration.The evolution processes of the tectonic stress field can be divided into four periods:(1) The first period occurred in the Wulashan movement of Late Archean.The orientation of σ1(the maximal principal stress of the structurally deformed stress field) was 15°~195°,which formed conjugate joints with NNW and NE trending structures.In addition of the penetrative,small,strong ductile superposed folds,large complex anticlines were formed during the diagenesis and metamorphism periods.(2) The second period occurred in Late Paleozoic.The orientation of σ 1 was about 160°~340°,which led to the formation of the SN and NE-trending conjugate joints and the intrusion of the Dahuabei pluton.Local mineralization was formed in this period.The two periods of pro-mineralization deformation resulted in the nearly EW-trending superposition-folds,faults and conjugate shear joints.(3) The third period deformation was the main ore-forming period took place in the Middle to Late Yanshanian.With the σ 1 orientation of 290°,EW and NW-trending conjugate shear joints were formed by horizontal compresso-shear effect.Tenso-shear stress field made the early EW-trending joints bended,and formed tracking-expansion joints.These two kinds of fractures became the main ore-fluid channels and ore-forming spaces.(4) The fourth period post-mineralization deformation occurred during and after the Late Yanshanian.The nearly upright σ1 caused the tectonic uplift and resulted in the exposure and denudation of the mining area.

The Xishimen gold deposit is located in the tectonic zone southeast to the Shihu gold deposit, both of which belong to the same orefield. Then, how is the prospecting potential for the Xishimen gold deposit? A com-parison was made between the Xishimen gold deposit and the Shihu gold deposit on the basis of their geological background of metallogenesis, geological characteristics of the ore deposits, the sources of ore-forming materials, etc. The results showed that both the deposits possess many similarities in the respects mentioned above. And their met-allogeneses can be compared. Therefore, there is great potential for ore prospection in the periphery or at the deep levels of the Xishimen gold deposit. Ore exploration should be well programmed on the basis of a better dissection of the tectonic setting of the orefield. A breakthrough in ore prospection of the Xishimen gold deposit will be of great instructive significance in regionally geological prospecting.

Xishimen gold deposit is located in axis of Fuping mantle branch structure, Southeast of Yanshanian Mapeng granitic intrusion. In this paper, based systematic analysis on sulfur, lead, hydrogen, oxygen and carbon isotopic composition of Xishimen deposit and deposits in the region, the results show that:the sulfide δ34 S ranges from -0.3 ‰～ +1.4 ‰, average 0.63 ‰ , consistent with sulfur isotopic composition of the region, Falling into the range of mantle-derived sulfur, indicating that sulfur is mainly deep source; lead isotope range narrowly, consistent with lead isotopic composition of the region, indicating that they are of the same source. In the Lead isotopic composition, all the lead isotopes falled between the upper mantle and lower crust; hydrogen and oxygen isotopes show that the ore-forming fluids are mainly magmatic water in the early stage and mixed with some of the meteoric water in the later; carbon isotopes show that the ore-forming hydrothermal fluids derived from the mantle, Therefore, it have shown that the ore-forming materials of Xishimen gold deposit should come from the deep interior of the Earth, and the dynamic mechanism of ore-forming materials moving upwards is the multi-stage evolution of mantle plume. During the multi-stage evolution of mantle plume, especially the ore-forming materials found their way into the crust vias the mantle, it is inevitable that some crustal material would have been involved. Therefore, the measured isotope data always fall between the typical mantle-source area and the crust-source area.

张-宣地区是河北省金银多金属矿床集中区,可划分出以宣化—崇礼—赤城一带岩浆-变质杂岩区为中心的金矿集中区和外围盖层区的银多金属矿分布区。近年研究表明,金银多金属成矿物质主要来自地球深部,通过地幔热柱多级演化向上迁移,并在幔枝构造的有利构造扩容带中集聚成矿。分别以幔枝构造核部的东坪金矿、拆离带的黄土梁金矿和外围断陷盆地中的万全寺银金矿为例,通过其成矿作用的解剖、分析、归纳认为,在张-宣幔枝构造展布区,平面上从核部向外围,垂向上由下部往上部,均具有金→银→铅锌矿的分带性,并已经在多处矿山得到采矿工程或钻探工程的证实,这对于深部找矿具有重要指导意义。同时据此分析表明,张-宣幔枝构造区深部仍具有很大的找矿潜力,这种成矿作用分析也可以推广到成矿地质条件相近的幔枝构造区。