(1. 中南大學 地球科學與信息物理學院，長沙 410083；
2. 中南大學 有色金屬成礦預測與地質(zhì)環(huán)境監(jiān)測教育部重點實驗室，長沙 410083；
3. 貴州大學 資源與環(huán)境工程學院，貴陽 550025；
4. 山東省第一地質(zhì)礦產(chǎn)勘查院，濟南 250100)
摘 要: 膠萊盆地郭城－崖子斷裂帶是國內(nèi)近年來發(fā)現(xiàn)的一個重要金成礦區(qū)，陸續(xù)探明了一批大中型-超大型金礦床。然而，該礦集區(qū)的深部找礦勘查工作一直沒有取得重大突破。本文通過系統(tǒng)采集成礦巖體樣品，挑選磷灰石單顆粒礦物，采用裂變徑跡熱年代學方法，揭示研究區(qū)巖體(礦體)溫度-時間演化關(guān)系，反演巖體(礦體)熱演化歷史，解析成礦后構(gòu)造對礦床的改造，定量計算巖體(礦體)抬升-剝蝕速率，總結(jié)礦床變化保存規(guī)律。結(jié)果表明：郭城－崖子斷裂帶金礦集區(qū)主要經(jīng)歷了110~20 Ma和20~0 Ma兩個階段的成礦后熱史，兩階段不均勻的隆升冷卻過程受到了太平洋多期增生擴張過程的影響。根據(jù)對磷灰石裂變徑跡熱歷史演化分析，結(jié)合區(qū)域古地溫梯度、成礦深度以及侏羅紀和白堊紀陸相沉積地層厚度，計算得出研究區(qū)內(nèi)白堊紀至今地層總剝蝕深度約為5.33 km，金礦帶礦體成礦深度為5.62 km，表明郭城－崖子斷裂帶內(nèi)礦體遭受了較大程度的抬升剝蝕，推測斷裂帶南西向地層剝蝕少的部位有較大的找礦潛力，并建立了郭城－崖子斷裂帶深部金礦體定位模型，評價了深部找礦潛力。
關(guān)鍵字: 鵲山巖體；牧牛山巖體；熱史模擬；隆升剝蝕；深部勘查；成礦深度
（1. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China;
2. Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Central South University, Changsha 410083, China;
3. College of Resources and Environmental Engineering, Guizhou University, Guiyang 550025,China;
4. No.1 Institute of Geology and Mineral Resources of Shandong Province, Jinan 250100, China）
Abstract:The Guocheng-Yazi fault belt in the Jiaolai basin is an important gold metallogenic area discovered in recent years, and a number of large and medium-sized to super-large gold deposits have been discovered continuously. However, n the deep prospecting and exploration work in the ore concentration area has not made a major breakthrough. In this paper, through the systematic collection of ore-forming rock and ore samples, the apatite single mineral was separated. The fission track thermochronology method was used to reveal the temperature-time evolution of the ore body in the study area. We inversed the thermal evolution history of the rock mass and ore body, analyzed the structural transformation of the deposit after mineralization, quantitatively calculated the uplift denudation rate of the rock mass and ore body, and summarized the denudation and preservation law of the deposit. The results show that the Guocheng-Yazi fault zone gold concentration area mainly experienced two stages of post-mineralization thermal history of 110-20 Ma and 20-0 Ma, and the two-stage uneven uplift and cooling process was affected by the multi-stage proliferation and expansion process of the Pacific Ocean. Based on the analysis of the thermal history evolution of apatite fission track, combined with the regional paleogeothermal gradient, metallogenic depth and the thickness of Jurassic and Cretaceous continental sedimentary strata, the total erosion depth of the strata in the study area from Cretaceous to now is calculated to be about 5.33 km, and the metallogenic depth of the ore body in the gold belt is 5.62 km, indicating that the ore body in the Guocheng-Yazi fault zone has been subjected to a large degree of uplift and denudation. It is speculated that the part of the fault zone with less erosion of the southwest strata has great prospecting potential, and the deep gold ore body positioning model of the Guocheng-Yazi fault zone is established to evaluate the deep prospecting potential.
Key words: Queshan pluton; Muniushan pluton; thermal history simulation; uplift-denudation; deep exploration; metallogenic depths
