CAJ | 학술논문

为查明长乐—南澳断裂带现今地应力状态和活动现况,在该断裂带中段泉州市区北侧开展了600 m深度钻探工程和随深度系统水压致裂现今原位地应力测量工作,在钻探深度内成功完成了21段地应力大小测试和4段最大水平主应力方向测试。随深度系统的地应力测量结果表明：①水平主应力量值处于高值状态且三个主应力大小之间关系为 SH>Sh>SV,表明区域构造作用强烈且水平应力起主导作用,易于逆断层发生。②现今最大水平主应力方向为北西西向,反映北东向的长乐—南澳断裂带中段现今活动具有右行走滑的特征。③基于实测数据计算得到μm 和 R,μm=0.44~0.76,反映了该区域相对很高的应力积累水平；R=0.44~0.65,说明此应力状态有利于该区域内断层的活动。依据实测地应力结果表明,长乐—南澳断裂带中段的应力状态已经达到断层活动的临界值,断裂活动进入临界状态,具有逆断层发生滑动的潜在危险性,值得重点关注和深入研究。研究成果为长乐—南澳断裂带中段现今活动性研究补充了新的动力学数据,为地震地质研究和城市安全评价提供了依据。
위사명장악—남오단렬대현금지응력상태화활동현황,재해단렬대중단천주시구북측개전료600 m심도찬탐공정화수심도계통수압치렬현금원위지응력측량공작,재찬탐심도내성공완성료21단지응력대소측시화4단최대수평주응력방향측시。수심도계통적지응력측량결과표명：①수평주응역량치처우고치상태차삼개주응력대소지간관계위 SH>Sh>SV,표명구역구조작용강렬차수평응력기주도작용,역우역단층발생。②현금최대수평주응력방향위북서서향,반영북동향적장악—남오단렬대중단현금활동구유우행주활적특정。③기우실측수거계산득도μm 화 R,μm=0.44~0.76,반영료해구역상대흔고적응력적루수평；R=0.44~0.65,설명차응력상태유리우해구역내단층적활동。의거실측지응력결과표명,장악—남오단렬대중단적응력상태이경체도단층활동적림계치,단렬활동진입림계상태,구유역단층발생활동적잠재위험성,치득중점관주화심입연구。연구성과위장악—남오단렬대중단현금활동성연구보충료신적동역학수거,위지진지질연구화성시안전평개제공료의거。
To explore the in-situ stress in the Changle-Nan’ao fracture belt and its present activity, the authors gathered data from 21 segments for in-situ stress measurement and from 4 segments for orientation of major principal stress varying intervals along the drill hole with total depth of 600 m located inside a granite-rich region in the northern part of Quanzhou City. Combined with the high in-situ stress data ofSH>Sh>Sv, the core sampling of the structure features of shallow earth crust rock formation reveals that current horizontal principal stresses play a leading role in reverse fault activity. Moreover, measured maximum principal in-situ stress strikes in NWW direction and reflects present compressive properties, with dextral slip activity, of the middle segment. Calculated through measured principal stresses, the magnitudes of feature parametersμm andR reach 0.44~0.76 and 0.44~0.65 respectively, which reflect the high-stress accumulative capability of the regional crust and availability for the activity of fault movement in this area. The measured results indicate that the state of in-situ stress has reached the critical value, the activity of the fault is approaching the critical state, and the potential risk of the reverse fault has the tendency of sliding and shearing failure. With pre-existing research result, these new dy-namic data will allow us to open new research avenues for understanding the present active features of the middle segment of the Changle-Nan’ao fracture belt and to provide a basic guarantee for the earthquake research and ur-ban safety.