地球学报
地毬學報
지구학보
ACTA GEOSCIENTIA SINICA
2009年
6期
787-795
,共9页
胡东生%张华京%徐冰%白建斌%田新洪%王旭龙%宋友桂%于学锋%刘卫国%安芷生%张国伟
鬍東生%張華京%徐冰%白建斌%田新洪%王旭龍%宋友桂%于學鋒%劉衛國%安芷生%張國偉
호동생%장화경%서빙%백건빈%전신홍%왕욱룡%송우계%우학봉%류위국%안지생%장국위
岩石微裂隙%冷构造系统%陆面表层冰冻作用%地质环境响应%地球动力学机制
巖石微裂隙%冷構造繫統%陸麵錶層冰凍作用%地質環境響應%地毬動力學機製
암석미렬극%랭구조계통%륙면표층빙동작용%지질배경향응%지구동역학궤제
micro-fissure of rock%cold structural system%frost action on the land surface%response of geological environment%geodynamic mechanism
经过多年的区域地质调查和第四纪环境演变的分析,对庐山芦林盆地大校场谷口剖面松散沉积物中变形砾石进行岩石显微构造学的研究.发现变形砾石内部存在特殊的微裂隙组构,呈现出错裂-横裂-劈裂-爆裂-复裂-应力矿物等的复杂组合,其结构面特征反映出显微构造形迹的力学性质是互为转变的.通过物理模型分析和试验变形比对等综合材料证明,变形砾石是遭受了既密集、又分散、还具有同时发生作用的长时期的多边界外力条件及平衡力系,内部形成破裂其应力传递过程和性质改变与变形形迹转变及其做功连续扩展,是由低于疲劳极限的具有脉动性作用微弱应力造成的.地球陆表过程和地质环境要素及其动力学机制的研究认为,只有第四纪晚期地质事件的低温、低应力及其分散密集的多颗粒平衡力系的缓慢长期及间歇脉动作用的边界条件才能满足、符合及形成这种特殊的岩石变形构造,为中国东部山地可能遭受第四纪冰冻环境及冰川作用提供了新的科学证据.
經過多年的區域地質調查和第四紀環境縯變的分析,對廬山蘆林盆地大校場穀口剖麵鬆散沉積物中變形礫石進行巖石顯微構造學的研究.髮現變形礫石內部存在特殊的微裂隙組構,呈現齣錯裂-橫裂-劈裂-爆裂-複裂-應力礦物等的複雜組閤,其結構麵特徵反映齣顯微構造形跡的力學性質是互為轉變的.通過物理模型分析和試驗變形比對等綜閤材料證明,變形礫石是遭受瞭既密集、又分散、還具有同時髮生作用的長時期的多邊界外力條件及平衡力繫,內部形成破裂其應力傳遞過程和性質改變與變形形跡轉變及其做功連續擴展,是由低于疲勞極限的具有脈動性作用微弱應力造成的.地毬陸錶過程和地質環境要素及其動力學機製的研究認為,隻有第四紀晚期地質事件的低溫、低應力及其分散密集的多顆粒平衡力繫的緩慢長期及間歇脈動作用的邊界條件纔能滿足、符閤及形成這種特殊的巖石變形構造,為中國東部山地可能遭受第四紀冰凍環境及冰川作用提供瞭新的科學證據.
경과다년적구역지질조사화제사기배경연변적분석,대려산호림분지대교장곡구부면송산침적물중변형력석진행암석현미구조학적연구.발현변형력석내부존재특수적미렬극조구,정현출착렬-횡렬-벽렬-폭렬-복렬-응력광물등적복잡조합,기결구면특정반영출현미구조형적적역학성질시호위전변적.통과물리모형분석화시험변형비대등종합재료증명,변형력석시조수료기밀집、우분산、환구유동시발생작용적장시기적다변계외력조건급평형력계,내부형성파렬기응력전체과정화성질개변여변형형적전변급기주공련속확전,시유저우피로겁한적구유맥동성작용미약응력조성적.지구륙표과정화지질배경요소급기동역학궤제적연구인위,지유제사기만기지질사건적저온、저응력급기분산밀집적다과립평형력계적완만장기급간헐맥동작용적변계조건재능만족、부합급형성저충특수적암석변형구조,위중국동부산지가능조수제사기빙동배경급빙천작용제공료신적과학증거.
Based on many years work of regional geological investigation and an analysis of Quaternary environ-ment development, the authors studied the microscopic structure of the deformed gravels in loose sediments along the Dajiaochang valley section in Lulin basin of Lushan area and detected the existence of the special mi-cro-fissure fabric inside the deformed gravel, which assumes the complex assemblage of displacement crack -transversal crack - cleavage crack - explosion crack - composite crack - stress minerals, whose structural plane characteristic show that the mechanic qualities of the microscopic structure features are interchangeable. Synthetic material data and physical model analysis as well as experimental deformation contrast have demonstrated that the deformed gravel underwent the prolonged and simultaneous multi-boundary external force condition and the equi-librant system characterized by intensiveness and scattering. The internal breaking, the stress transmission process, the quality variation with the change of the transformation structure features and the continuous expansion of the work-doing resulted from the weak stress of the pulsation action lower than the fatigue limit. Researches on the earth's land surface processes and the geological environment essential factor and its dynamic mechanism have demonstrated that only with the equilibrant system of the low-temperature and low-stress and the scattered as well as dense multi-grains, the boundary condition for the slow, long-term and intermittent pulsation action can meet the formation conditions of such a rock deformation structure. These achievements have provided new scientific evidence for the possible existence of Quaternary frost environment and glacial action in mountainous areas of eastern China.
