(1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Central South University,
Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China)
摘 要: 從礦床地球化學(xué)特征入手，對(duì)礦區(qū)的磯頭復(fù)式巖株、1號(hào)礦體礦石、矽卡巖和礦體圍巖(黃龍組和船山組的灰?guī)r)的常量元素、稀土元素和微量元素特征進(jìn)行探討。結(jié)果表明：磯頭復(fù)式巖株的閃長(zhǎng)巖類巖石屬于硅酸弱飽和類鈣堿性準(zhǔn)鋁質(zhì)巖石，其巖漿主要來(lái)源于上地幔，且在巖漿上升過程受到了地殼物質(zhì)的混染；巖體中Cu元素強(qiáng)烈富集，巖漿具備提供成礦物質(zhì)的潛力；1號(hào)礦體中的礦石稀土配分曲線、∑REE和6種常見成礦元素(W、Sn、Cu、Pb、Zn、Ag)含量均與巖體和矽卡巖的相近，而與黃龍組和船山組灰?guī)r的相差較大。在此基礎(chǔ)上，結(jié)合新橋銅硫鐵礦床的控礦因素、巖體地球化學(xué)特征、礦石結(jié)構(gòu)構(gòu)造、圍巖蝕變、礦石礦物分帶特征、礦床地球化學(xué)特征、成礦物質(zhì)來(lái)源以及與典型Sedex礦床和矽卡巖礦床的對(duì)比，得出巖漿是區(qū)內(nèi)成礦的必要因素，新橋銅硫鐵礦床應(yīng)是以接觸交代作用為主的矽卡巖型銅硫鐵礦床。
關(guān)鍵字: 新橋；礦床地質(zhì)特征；地球化學(xué)特征；控礦因素；礦床成因
（1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Central South University,
Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China）
Abstract:The geochemical characteristics in macroelements, REE and trace elements of Orebody No.1, skarns and wall rocks (limestones in Huanglong Group and Chuanshan Group) were discussed. The results show that Jitou rock strains are weak silicate saturated, vice-metaluminous and calc-alkaline, originated from upper mantle and contaminated by crustal materials during digenetic evolution process. The element Cu in Jitou rock Strains is so rich that the magma has the potential to supply metallogenic substances, and the REE distribution curves, ∑REE and contents of six metallogenic elements (W, Sn, Cu, Pb, Zn, Ag) of ore in Orebody No.1 are similar to ones of Jitou rock strains and skarn, but different from ones of limestones in Huanglong Group and Chuanshan Group. On these basis, the genesis of the deposit was studied by analyzing ore-controlling factors, geochemical characteristics of Jitou rock strains, ore structures, alteration of wall rock, mineral zonation, geochemical characteristics of the deposit, source of ore-forming materials and comparison among typical Sedex type deposit, skarn type deposit and Xinqiao Cu-S-Fe deposit. The conclusions are that the magma is the necessary factor of the mineralization, and that Xinqiao Cu-S-Fe deposit is skarn-type Cu-S-Fe deposit because of its contact metasomatism.
Key words: Xinqiao; geological characteristics of deposit; geochemical characteristics; ore-controlling factors ; genesis of deposit
