中文摘要:燕山中期岩浆同化混染中奥陶统含蒸发岩层的碳酸盐岩形成富钠和挥发组分的岩浆，为岩浆后期及期后钠化、矽卡岩化及热液蚀变提供了主要物源。钠化过程中萃取了铝硅酸盐岩中的铁、钾、钙及镁等，之后，含矿气液沿减压释放带迁移，并聚集交代成矿。对某些蚀变矿物特征的研究表明，钠化、矽卡岩化和热液蚀变是交代成矿作用的统一过程，蚀变矿物学特征，不仅揭示了该矿床形成时的地质环境，物理化学条件及其演化过程的规律，并且对邯邢式铁矿床的找矿评价具有标志作用。
Abstract:A study on alteration mineralogy of the Hanxing type iron deposits suggests that their iron substance and gas-fluids were mainly derived from the ore-related diorite-monzonite bodies at small depths. During its emplacement, the Yanshanian magma contaminated and assimilated Middle Ordovician evaporite-bearing carbonate rocks and thus formed such volatile-rich accessory minerals as fluor- (chlor-) apatite, tourmaline and pyromorphite as well as andesine with anti-zonal structure, suggesting that, as the magma was rich in sodium and volatile components (Table l,8, 9), it served as the main material source for late and post-magmatic stage albitization, skarnization and hydrothermal activities. The intensity of albitization usually implies the size of iron deposits. During the albitization, iron, potassium, calcium and magnesium were extracted from aluminosilicate (Table 9), and iron substance was transferred into gas and hydrothermal fluids in the form of complexes (K, Na) 〔Fe (Cl, F) 4〕and (K,Na)2 (Fe (CI,F)4) and then migrated towards and concentrated at the decompression-discharge zone. Calculation shows that iron amount released in the process of albitization is approximately equivalent to proved iron reserves at the contact zone. After albitization, the gradually decreasing temperature led to the variation in components of gas and liquids, and these gas and liquids originally accumulated at the decompression-discharge zone in the uplifted or protruding position of the rock body replaced albitite and Ca-Mg rich carbonate rocks, forming endoskarn zone dominated by scapolite (Table 2) and exocontact zone dominated by diopside (Table 3) and andradite (Table4). Large quantities of magnetite were farmed through replacement of diopside and carbonate rocks at the above-described position during the trartsition from gas-liquid phase to liquid phase. With the crystallization of magnetite in considerable quantities, such components as K+, F-, C1- and (OH)- were progressively accumulated in hydrothermal fluids; and the more magnetite was formed, the higher the concentration of these components, which replaced magnetite and diopside to form increasing amounts of phlogopite rich in potassium, fluorine and magnesium and poor in iron (Table 6) .The intensity of phlogopitization is therefore frequently in direct proportion to the size of the ore deposit. The decompression-discharge zone formed at the uplifted or protruding contact zone of the rock body and the associated fractures and fissures constituted an important structural condition governing the unceasing activation, migration and accumulation of iron substance as well as regulation of pressure and acceleration of alteration and metasomatism. This structural condition was constantly effective from the pheumato-hydrothermal stage. Although belonging to different metasomatic stages, albitization, skarnization and hydrothermal alteration were actually a unified process of the entire alteration and metasomatic mineralization. The characteristics of alteration mineralogy not only bring to light some regularities of geological environment, physical-chemical conditions and evolution of this deposit, but also serve as important indicators in prospecting and appraisal of the Hanxing type iron deposits
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许晓峰.1987.从邯邢式铁矿某些蚀变矿物学特征探讨矿床的形成[J].矿床地质,6(3):57~67.1987.A Tentative Discussion On The Formation Of The Hanxing Type Iron Deposits In The Light Of Alteration Mineralogy[J].Mineral Deposits6(3):57~67
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