三山岛海底金矿开采充填体与顶板岩层的变形监测研究

Monitoring and Research for the Deformation of Mine Backfill and Roof Surrounding Rock when Exploiting Sanshandao Seabed Gold Mine

三山岛金矿新立矿区是我国第一个从事海底基岩矿床开采的金属矿山,主要可采矿体均赋存于海底下部20~670 m的岩体中,矿体与海水间仅靠2~3 m厚的海底黏土隔水层隔离。为保障矿山安全生产,根据新立矿区具体的采矿地质条件,选择-200 m中段63线13#、71线17#和111线37#穿脉巷道,埋设了6个测点的埋入式智能记忆型位移计。每个穿脉巷道的测点均按2种方式布设：一种是上向倾斜钻孔穿过下盘围岩、充填体与下盘围岩的接触带和充填体,用以监测充填体与下盘岩体的相对变形;第二种是上向倾斜钻孔穿越F1主裂面下盘岩体和上盘岩体,用以监测断层上下盘岩体的相对变形。通过2013年9月至2014年12月的现场监测,获得了监测期间开采活动引起的充填体及顶板岩层的移动变形特征。监测结果表明,海底充填体和上盘围岩的变形量较小,表明三山岛金矿新立海底采场充填体和上盘围岩在监测期间保持了很好的稳定性。

Xinli deposit of Sanshandao gold mine is the first exploited hard rock mine under seawater in China, which mainly occurred in seabed rock between 20 and 670 m in depth and covered by only 2 to 3 meters thick clay aquiclude under seawater.To ensure mining safety and according to mining geological conditions,six intelligently memory displacement meters had been buried in 13#, 17# and 37# transverse drifts along exploration lines of 63,71 and 111 ,respectively.Two buried ways were designed for the six meters.One was an updip drill threading through footwall rock into fill mass and for monitoring the relative deformation between backfill and footwall rock.Another one was an updip drill penetrating footwall rock and Ft main fracture surface into hanging wall rock and for recording the relative deformation between footwall and hanging wall rocks.And the deformation and movement characteristics of backfill and hanging wall rock have been obtained from September 2013 to December 2014.The results showed that the body of fill mass and hanging wall rock under seawater were subject to a comparatively small deformation and remained good stable during the monitoring process.