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采自广东南澳韧性剪切带和莲花山韧性剪切带的 6个单矿物的4 0 Ar/39Ar年龄谱数据可分为 3组 :151～ 162Ma、117.5～ 12 9.7Ma、66～ 97Ma。第 1组年龄代表较深层次逆冲、褶皱和动热变质的时代 ,该期间沿莲花山断裂带开始出现火山活动 ;第 2组年龄 ( 2 /3样品4 0 Ar/39Ar坪年龄值集中于这一组范围内 ) ,代表强烈韧性剪切、左行平移兼逆断层活动的时代 ,即韧性剪切带的形成时代 ,此期在南澳断裂带还发生了混合岩化和花岗岩化作用 ;第 3组年龄代表后期热扰动 ,即韧 脆性转化、右行平移 正断层活动和地壳伸展的时代。年代学资料还表明 ,莲花山断裂带西南段自 117.5Ma以来受伸展控制的冷却上升速率大约为 0 .0 3～ 0 .2 9mm/a。
The 4 0 Ar / 39Ar age spectrum data of 6 single minerals collected from the ductile shear zone of South Australia and the Lianhuashan ductile shear zone of Guangdong Province can be divided into three groups: 151 ~ 162Ma, 117.5 ~ 12 9.7Ma and 66 ~ 97Ma. The age of Group 1 represents the era of deeper thrusts, folds and thermal metamorphism. During this period, volcanic activity started to occur along the Lianhuashan fault belt. Group 2 age (2/3 samples) This group represents the era of intense ductile shear, left-lateral translation and reverse faults, ie, the formation of ductile shear zones. During this period, there were also mixed rocks and granitization in the Nan’ao fault zone. The three groups of ages represent the post-thermal disturbance, that is, the era of ductile and brittle transformation, right-lateral translation normal fault activity and crustal extension. The chronological data also show that the rate of increase of cooling controlled by extension in the SW section of the Lianhuashan fault zone since about 117.5Ma is about 0.30 ~ 0.29mm / a.