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石场-中楼盆地位于郯庐断裂带中段的沂河-沭河地区.郯庐断裂左旋切割了秦岭-大别-胶南造山带及前中生代地层,研究区内沂河-沭河断裂切割了年龄为136.2Ma(40Ar/39Ar法)的胶南造山带北缘剪切带,并被时代为119Ma(K-Ar法)的青山群地层不整合覆盖,显示郯庐断裂在早白垩世曾发生了明显的走滑运动.石场-中楼盆地受沂河-沭河断裂的控制,整体为长60km、宽30km,长宽比近于2:1的“菱型”构造盆地.盆地内早白垩世莱阳群的沉积厚度大于6 263.71m,沉积速率大于0.4mm/a;沉积相特征反映盆地具有深而窄,沉积速度快、沉积相变剧烈的特点.盆地沉积中心的迁移方向与边界断裂的左旋走滑效应一致,“边走滑边沉积”的特征明显.根据构造背景、构造格架及沉积特征,确定石场-中楼盆地为郯庐断裂早白垩世左旋走滑过程中形成的拉分盆地.“,”The Shichang-Zhonglou basin is situated in the Yihe-Shuhe area at the middle section of the Tan-Lu fault zone. The strike-slip Tan-Lu fault cuts the Qinling-Dabie-Jiaonan orogen of PreMesozoic,while in the study area the Yihe-Shuhe (Yi-Shu) fault overlies the north margin shear zone of the Jiaonan orogen,which gives out an 40Ar/39Ar age of 136.2 Ma. The faults are unconformably covered with the Qingshan Group of the age of 119 Ma (K-Ar whole rock). These evidence show that the Tan-Lu fault had significant strike-slip movement. The Shichang-Zhonglou basin is controlled by the Yihe-Shuhe fault,it occurs as a rhombachasm tectonic basin with a length 60 km and a width 30 km. The thickness of the Early Cretaceous Laiyang Group in the basin is more than 6 263. 7m. The sedimentation rate is greater than 0. 4mm/a. The fast changing sedimentary facies in the Laiyang Group reflects that the basin was narrow and deep. Migration of the sedimentation center is consistent with the strike-slip boundary faults showing the characteristics of “depositing while strike-slip moving”. It is suggested that the Shichang-Zhonglou basin is a pull-apart basin formed during the process of sinistrial strike-slip movement of the Tan-Lu fault zone in early Cretaceous.Key wards: Tancheng-Lujiang fault zone, Active fault, Pull-apart basin, Early Cretaceous.