| Pointing to present condition of research and achievements gained in gold exploration, by using continental dynamics research method and mineralization theory, combining field survey with information study, combing important gold mines anatomy with test samples, and on the basis of analyzing structure, ore controlling rule of Yishu fault belt is studied in this paper. New recognition of ore-forming materials and ore mineralization are put forward as well.Yishu fault belt is composed of four main faults with the type of "two faulted troughs with one horst".△T aeromagnetic anomalies appear as a series of linear type anomaly belts with the trend of north-north-east to north-east and beaded anomaly belt. They showed as gravity gradient belts with the trend of north-north-east in Bouguer gravity anomaly map. The structural line directions of the crystalline basement have different characteristics with those on both sides of the basement rocks, and controlled the strata distribution and the development level of magmatic rocks.Through detailed study on profiles of the structures, it is showed that activity styles of Yishu fault belt in different sections in different stages have obvious diversity. It caused complicated metamorphic characteristics of structures, such as toughness and brittle, squeeze and stretch, left rotating and right rotating. Combining with geophysical detection information, it is regarded that Yishu fault belt both has the cutting mantle characteristics of the deep fault, and spade fracture performance in shallow part. After experiencing long and multi-phase tectonic movements, its structures have become very complicated.Yishu fault belt was formed in Neoproterozoic period with the property of ancient Yishu rift. The ancient Yishu rift was closed due to Jinning movement and formed unified ancient land in Ludong (eastern Shandong province) and Luxi (western Shandong province) areas. Crusts on both sides of the fault occurred differences in movements. Ludong area uplift in long time, and erosion was its major movement and deposition only occurred in partial areas. After the Hercynian and Indo-China movement, the former structure line changed from north-east trend to north-north-east trend. In Mesozoic period, eastern China started the change from central Asia and Tethys tectonic domain to the Pacific tectonic domain stage. The Mesozoic and Cenozoic periods were strong movement stages. They would cause the mantle replacement in eastern China and the lithosphere thinning in Mesozoic and Cenozoic period. At the same time, the Qin-Qi-Kunyang basin clamping between the north China plate and the Yangtze plate occurred collision and orogenic movement. It would cause strong activation of the Yishu fault belt and a large-scale shift to the left, the subsequent napping, translating to the right side and splitting. Under this structural background, structural pattern, sedimentation, magmatic activities and the form and distribution of minerals were effected by Yishu fault belt obviously. Due to subduction of the Pacific plate, Yishu fault belt located in marginal rift of continental movement. Magmatic lava in the upper part of the mantle pulped out from this area and provided sources and heat for mineralization. Due to thermal function of the plate in east part, a large number of multi-phase granite rock were formed after crust material remelting, which became important parent of gold mineralization in Jiaodong area. Yishu fault belt were translated to left accompanying with splitting in Paleogene, and evoluted to rift in later period. The movement in Neogene would translate at the left side with strong magmatic movement, while the movement in Quaternary showed differences in movements for the campaign.The continental dynamics environment with strong activities in Yishu fault belt originated from the transformation of central Asia-Tethys tectonic domain to the foreshore Pacific tectonic domain, and the Pacific plate subduction. Under the background of north China plate and the Yangtze plate collision orogenic activity, and the subduction of Pacific plate to the NWW trend, the activation of Yishu fault belt and its translation to the left occurred. The largest translation distance was over 300km. The Cenozoic had the characteristics of extension and squeeze in turn, and the structural framework with rift characteristics was formed.Gold deposits in Yishu fault belt can be divided into 5 types according to its origins; they are post-magmatic hydrothermal alteration with broken rock type, post-magmatic hydrothermal fracture filling quartz vein, contact skarn type, and the outbreak of crypto-volcanic hydrothermal breccia sedimentary rock type. Altered rock type gold deposits were mainly distributed in Yishui-Tangtao fault belt, and mineralization mainly occurs in mylonite granite, granite rock fragmental and green schist. The boundary between ore and non-ore was not very clear. The definition of ore bodies was determined by sample analysis result, and the ore body shapes were controlled by faults and ductile shear belts. Quartz vein type gold deposits occurred in basement rocks or Mesozoic rocks in the fault fissures. Ore bodies were gold-bearing pyritiferous quartz vein which had clear boundaries with country rocks. Parent rock of contact type gold deposit was the intruded complex in multi-stage Mesozoic Yanshan period. Its components were partial basis or partial acid to basis magmatic rocks. It was majorly composed of stratoid or phacoidal type, accompanying with lenticular and sackform type. Crypto-volcanic hydrothermal gold deposit located in the intersection part of Jiaolai basin and Yishu fault belt. Ore bodies mainly occurred in crypto-volcanic rocks and volcanic rocks of Qingshan group, while a small amount occurred in intrusive rocks. The mineralization rocks were quartz diorite porphyry-granite porphyry, diorite, diorite porphyry, Anshan tuffaceous breccia and andesite, etc. Ore bodies occurred in crypto-explosive breccia pipes which have close relation with volcanic complex. The crypto-volcanic complex was important ore leading and ore bearing geological bodies. Copper and lead-zinc deposits were mainly low-medium thermal fracture filling type, and were mainly distributed in sub-faults in both sides of regional deep faults. They were formed in late Yanshan period. Sapphire deposit occurred in Yishu fault belt. They were mainly occurred in central part of volcanic eruption of Neogene basalt. According to mineralization time, deposits caused by different origins occurred in different structural sections, different geological environment and different ore-forming times. The whole mineralization sequence was gold, copper, lead-zinc and sapphire from old to new.Different types of deposits were formed by different tectonic and magmatic function in different stages. Yanshan period is an important gold mineralization period. It formed a unique gold mineralization and ore-forming series in Shandong province. According to the mineralization characteristics, it can be divided into three deposit forming series combinations and 15 deposit series.Gold deposits in Yishu fault belt mainly occurred in mylonitic fragmental and granite rocks in lower part of main fracture in Yishui-Tangtao fault belt. Gold content in granite of major geological ore bodies is higher in Taishan group and Yanshan group. Its standard deviation and variation coefficient is large. They are major parent gold mineralization rocks, particularly the magmatic activities in Yanshan period are important factors for gold mineralization in this area. Pyritization, silication and beresite have close relation with gold deposit. Gold was composed of natural gold and silver gold. Gold ores were mainly showed as brecciform, accompanying with sub-brecciform, branched and line types, and the average component of gold mineral is 816.Through study on calcite inclusions and quartz inclusions in altered rock type and quartz vein type gold deposits, it is showed that inclusions have three types, such as single liquid phase inclusion, gas-liquid phase inclusion and gas-rich inclusion. Its freezing temperature varies between-2℃～-8.6℃, the salinity is between 3.39 wt%～12.39wt%, that is medium degree salinity (or deep source fluid) and low degree salinity deep water circulation of the atmosphere fluid; salinity in calcite fluid is relatively low, which is estimated as the result mixing magmatic fluids and atmospheric water. Uniform temperature of inclusions has a wide variation range between 107℃～550℃, and can be divided into 3 peak temperatures as 125℃～160℃,177℃～230℃and 260℃～330℃. They respectively reflect the early mineralization stage which regarded quartz as the representative (260℃～330℃), medium mineralization stage which regarded low-temperature quartz and calcite as the representatives (177℃～260℃), and late mineralization stage which regarded low-temperature calcite as the representative (125℃～160℃).As showed by stable isotope data of sulfur, hydrogen, oxygen, carbon and lead in typical gold deposits in this region,δ34 S value of pyrite varies between+2.7～+4.4‰,δ18O H2O value varies between-1.78～4.07‰,δD (SMOW) value varies between-74～-77‰, and the average value ofδ13 C is-4.18～-5.1‰. Isotope of lead has the characteristics of normal lead, which showed that gold-forming minerals are from deep part of underground. Ore-forming fluids are majorly composed of magma water accompanying with air precipitation.Rare earth elements of altered quartz and feldspar have some similar characteristics. They both are smooth curves with right tilt, and belong to light rare earth element concentration type. However, the difference between the two is obvious, the total content of rare earth element in feldspar is the highest, and light rare earth element concentration is even more evident with negative performance of the Eu anomaly; total content of rare earth element in quartz is low, and light rare earth element concentration is not evident, and the performance of the Eu is abnormal.U-Pb isotopic dating of zircon in Nanxiaoyao gold deposit is determined. The age of 2438±13Ma can represent the forming age of basic rocks, and 116±20Ma may represent a general time limit of regional mineralization. K-feldspar minerals in Longquanzhan gold deposit, Nanxiaoyao gold deposit and Niujiaxiaohe gold deposit are determined by using K-Ar method. Their ages are 141.92±2.06 Ma,94.29±1.38 Ma and 95.92±1.40 Ma respectively. The gold deposits in this area were formed in early and late Cretaceous period.20 whole-rock and single ore in Tongjing area of Yinan county are determined by using K-Ar dating method, the age is between 110～126 Ma. The age of other groups determined by Rb-Sr isochronal dating is 113.4 Ma. These data reflect that gold mineralization age should be in the Cretaceous period.Through primary summary on gold mineralization rule in this area, it is regarded that the ore-rich source rocks, strong ductile shear function in Jinning group, and large scale of volcano-magma thermal incident are factors for causing gold mineralization in this region. According to geological data and study on ore-forming minerals, gold ore-forming model is set up in this area.
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