黑龙江小兴安岭-张广才岭地区元古宙地(岩)层特征及成岩时代

STRATIGRAPHIC CHARACTERISTICS AND DIAGENETIC AGE OF THE PROTEROZOIC ROCKS IN XIAOXINGANLING-ZHANGGUANGCAILING REGION,HEILONGJIANG PROVINCE

小兴安岭-张广才岭地区位于西伯利亚板块南缘佳木斯-兴凯地块.区内元古宙地(岩)层,包括古元古界东风山岩群和尔站岩群、中元古界黑龙江岩群和新元古界张广才岭岩群.每个岩群的原岩建造代表了陆内—陆缘拉张环境下的活动型(火山)沉积.由于构造改造,岩层间为总体有序局部无序构造接触.地质关系及同位素测年资料显示,其成岩时代为元古宙.他们总体上呈近南北向分布于佳木斯地块西缘、西侧,明显受佳木斯地块形成—增生演化历程所控制,均属于元古宙期间多次发育的陆内—陆缘裂谷构造环境的活动产物,并相应的配套发育了裂陷槽封闭、陆缘增生及同构造岩浆活动造山等地质构造事件,体现了多次开合、多旋回造山的构造体制.

The Xiaoxinganling-Zhangguangcailing region is tectonically located in Jiamusi-Xingkai massif in the southern margin of Siberia plate. The Proterozoic strata include the Paleoproterozoic Dongfengshan rock group and Erzhan rock group, the Mesoproterozoic Heilongjiang rock group and the Neoproterozoie Zhangguangcailing rock group. Each rock group represents the active （volcanic） sedimentation under the continental-continental margin extensional environment. Because of tectonic reformation, the structural contact between strata shows general order and local disorder. Geological and isotopic data indicate the diagenetic age of Proterozoic Eon. The rocks are generally distributed in N-S direction in the west side of the Jiamusi massif, obviously controlled by the forming-accretion evolution of the Jiamusi massif. The occurrences of the rocks correspond to tectonic events of the closure of fault-depression, continental accretion and synteetonic magmatic orogeny, reflecting the tectonic system of multiple opening-closing and polycyclic orogeny.