【摘要】：寺莊金礦床是近年勘查探明的位于膠東金礦集區(qū)焦家金礦帶最南端的一個(gè)超大型蝕變巖型金礦床,礦體全部產(chǎn)于蝕變帶內(nèi),然其流體-巖石反應(yīng)過程與金成礦機(jī)制尚未查明。為此,論文通過系統(tǒng)的野外和室內(nèi)研究,厘定了該礦床礦化類型和蝕變分帶,查明了其蝕變-礦化時(shí)空結(jié)構(gòu),探討了其金成礦機(jī)制,獲得如下主要認(rèn)識(shí):(1)蝕變類型有鉀長(zhǎng)石化、絹英巖化、黃鐵絹英巖化和碳酸鹽化,礦化類型有蝕變巖型、過渡類型和石英脈型。(2)蝕變礦化具有分帶性,主裂面向外依次發(fā)育黃鐵絹英巖帶→絹英巖化帶→鉀長(zhǎng)石化帶→玲瓏黑云母花崗巖帶,對(duì)應(yīng)礦體依次為蝕變巖型→過渡類型→石英脈型→無礦體。蝕變礦化具有多次脈動(dòng)、疊加的特點(diǎn),從早到晚依次為鉀長(zhǎng)石化→絹英巖化和黃鐵絹英巖化,伴隨蝕變巖型礦化→石英脈型礦體形成→碳酸鹽化。(3)蝕變巖質(zhì)量平衡計(jì)算指示鉀長(zhǎng)石化過程Si O2、Al2O3、Fe2O3、Fe O、Mg O、Na2O、Au、Ag、As、Hg、Pb及稀土元素遷出,K2O遷入;(黃鐵)絹英巖化過程Si O2、Fe2O3、Fe O、K2O、Au、Ag、As、Hg、Cu、Sb、Bi及輕稀土遷入,Al2O3、Na2O及重稀土遷出。黃鐵絹英巖化過程Au變異系數(shù)14073.49%,是絹英巖化過程的16倍,鉀長(zhǎng)石化過程的283倍。(4)二長(zhǎng)石溫度計(jì)法計(jì)算指示鉀長(zhǎng)石化形成溫度為349~449℃,鉀長(zhǎng)石化花崗巖稀土元素顯示正銪異常,指示鉀長(zhǎng)石化發(fā)生在氧化環(huán)境下;流體包裹體顯微測(cè)溫指示成礦溫度集中于200~300℃,礦石稀土元素顯示負(fù)銪異常,指示成礦發(fā)生在還原環(huán)境下。根據(jù)礦物組合以及金與硫、氯的相關(guān)性,推斷金以金-硫絡(luò)合物的形式遷移,絹英巖化和黃鐵絹英巖化過程中石英和黃鐵礦的沉淀破壞了金-硫絡(luò)合物的穩(wěn)定保存條件,使得金從熱液中沉淀出來。
[Abstract]:The Sizhuang gold deposit is a super-large altered rock type gold deposit located at the southernmost end of Jiaojia gold belt in Jiaodong gold concentration area, which has been discovered in recent years. The orebody all occurs in the altered zone, but its fluid-rock reaction process and gold metallogenic mechanism have not been clarified. Therefore, through systematic field and laboratory studies, the mineralization types and altered zones of the deposit are determined, the time-space structure of alteration and mineralization is found out, and the mechanism of gold mineralization is discussed. The main conclusions are as follows: (1) the alteration type is potassium feldspathic. The types of mineralization are altered rock type, transition type and quartz vein type. (2) alteration mineralization is zonation. The main fracture faces to the outside and develops in turn the Yulinglong biotite granite belt along the kalium-feldspar lithochemical belt, corresponding to the altered rock type and transition type, quartz vein type and no ore body. Alteration mineralization has the characteristics of multiple pulsation and superposition. From early to late, the order of alteration mineralization is kalitization and yellowtigitization. The mass balance calculation of altered rocks indicates that Sio _ 2o _ 2AL _ 2O _ 3n Fe _ 2O _ 3O _ 2O _ 3 Fe _ 2O _ 3H _ 2O _ (O) O _ (2) O _ (2) O _ (2) O _ (2) O ~ (2 +) O ~ (2 +) O _ (2) O ~ (2 +) O ~ (2 +) O ~ (2 +) O _ (2) O _ 2O _ (3) Fe O _ 2O _ (3) Fe O _ (2) O _ 2 O _ 2 O _ (2) O _ (2) O _ 2 O _ (2) O _ (2) O _ (2) O _ (2) O _ 2 O _ (2) O _ (2) O _ (2) O _ The soil migrated to Al _ 2O _ 3, Na _ 2O and heavy rare earth. The coefficient of variation of au is 14073.49, which is 16 times of that of sericolith and 283 times of that of potassium feldspar. (4) the formation temperature of potassium feldspar is 349 ~ 449 鈩，

本文編號(hào)：2182406