摘要
沟-弧-盆体系恢复对于研究增生造山过程和解析成矿作用具有重要指示意义,多宝山岛弧带是我国重要的铜钼多金属成矿区带,其沟-弧-盆体系恢复对成矿地质背景研究及拓展区域找矿具有重要意义。通过对多宝山地区早古生代地层、岩石和构造的野外调研和系列编图,结合最新的年代学资料,重新厘定了含矿地层单位——多宝山组、铜山组的形成时代和层位:确定多宝山组形成时代为寒武纪芙蓉世-早奥陶世,铜山组形成时代为早-中奥陶世;将铜山组置于多宝山组之上,暗示地表以下保存有规模较大的主要成矿地质体——多宝山组,由此扩大了深部找矿空间。在此基础上,重建了多宝山岛弧带早古生代地层序列。在多宝山岛弧带西北侧多宝山-三卡一带划分出早古生代俯冲增生杂岩带,根据俯冲增生杂岩带与岩浆弧、伴生沉积盆地的沉积建造及时空关系,划分出弧前盆地、弧间盆地、弧后盆地等构造单元,建立了多宝山岛弧带古生代沟-弧-盆体系格架,认为多宝山岛弧带西北侧多宝山-三卡一带存在早古生代洋盆,并于奥陶纪发生南东向俯冲。指出岩浆弧靠近俯冲增生杂岩带一侧是成矿有利部位,为多宝山岛弧带铜多金属矿的成矿背景和成矿地质条件研究提供了理论依据。
Reconstruction of trench-arc-basin system such as Duobaoshan island arc belt,an important Cu-Mo polymetallic metallogenic zone in NW Heilongjiang Province,China,is crucial for both our understanding of the geological setting of ore-forming processes and future resource prospecting.According to the latest stratigraphical,petrological,field structural,geological mapping and geochronolgical studies,the formation age and stratigraphic sequence of the ore-bearing Duobaoshan and Tongshan formations were re-established,i.e.,the Duobaoshan and Tongshan formations are formed in Latest Cambrian to Early Ordovician and Early to Middle Ordovician,respectively.The redefined relationship between the Tongshan Fm.(upper)and the Duobaoshan Fm.(lower)indicated that a huge resource prospecting potential of Duobaoshan Fm.should be existed in the depth.Furthermore,we reestablished the Early Paleozoic stratigraphical system of Duobaoshan island arc belt based on above studies.There is an Early Paleozoic subduction-accretionary complex zone along Duobaoshan-Sanka region of NW Duobaoshan belt and forearc,interarc and backarc basins,and volcanic arcs between them to the SE,composing a Paleozoic trench-arc-basin system of Duobaoshan belt.An Early Paleozoic ancient oceanic basin was proposed at Duobaoshan-Sanka region which initiated a SE subduction from Ordovician.Thus,the advantageous metallogenic areas of the magmatic arcs are the parts that next to subduction-accretionary complex zone.This conclusion contributes to our realization of ore forming setting and geological condition of Duobaoshan polymetallic metallogenic belt.
作者
杨晓平
马江水
庞雪娇
杨雅军
江斌
付俊彧
YANG XiaoPing;MA JiangShui;PANG XueJiao;YANG YaJun;JANG Bing;and FU JunYu(Shenyang Center of Geological Survey,China Geological Survey,Shenyang 110034,China;Northeast Geological S&T Innovation Center of China Geological Survey,Shenyang 110034,China;Heilongjiang Institute of Natural Resources Survey,Harbin 150036,China)
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2022年第8期2269-2291,共23页
Acta Petrologica Sinica
基金
中国地质调查局项目(DD20160345-17、DD20190372、DD20221632)
国家研发计划项目深地资源勘查开采专项(2017YFC0601305-1)联合资助。
关键词
多宝山岛弧带
早古生代
沟-弧-盆体系
多宝山组
铜山组
年代学
Duobaoshan island arc belt
Early Paleozoic
Trench-arc-basin system
Duobaoshan Fm.
Tongshan Fm.
Geochronology
