莱芜弧形断裂,长期来被省内多数地质工作者所公认。近年我们对其进行了专题研究,认为它是由NW向的小楼～毛家庄断裂、近EW向的小王庄～狼山断裂及NEE向的泰安～大王庄～上迷马镇断裂相互交切而成,不存在具有统一的扭动方向和力学性质的弧形断裂,外形上也不是一园滑的弧形,而成折线状。这三条断裂具有不同的力学性质、扭动方向及活动方式,是在侏罗纪时太平洋板块开始发生和扩大,库拉板块向北偏西飘移,派生了NWW～SEE向挤压力而产生的一对NW、NEE的共扼扭裂面及近EW向的张裂面的基础上成生发展起来的,其活动一直延续到现在,经历了一个相当复杂的过程,具有极其复杂的面貌。就整个鲁西而言,NW和NEE向两组断裂亦广泛发育,它们相互交切构成“×”型构造骨架,并迭加上许多近东西向断裂,那种认为以尼山穹窿为砥柱经旋扭作用形成一系列鲁西弧的说法是难以成立的。 Laiwu arc fracture, long been recognized by the majority of geological workers in the province. In recent years, we conducted a special study on it and concluded that it is caused by the NW-oriented small house ~ Maojiazhuang fault, Xiaowangzhuang ~ Langshan fault near EW, and the Tai’an ~ Dawangzhuang ~ However, there is no arcuate fracture with a uniform twisting direction and mechanical properties, and the shape is not a circular arc of a park, but a polygonal line. The three faults have different mechanical properties, twisting directions and activities, which are the beginning of the Pacific plate in the Jurassic period and its expansion. The Qula plate drifts northward and westward, resulting in a pair of NWW ~ SEE squeezing forces NW, NEE conjugate twisting surface and the near EW to the crack surface developed on the basis of its activities until now, has gone through a very complex process, with an extremely complex face. For the entire Luxi, the NW and NEE also developed extensively to both sets of faults, and they intersect with each other to form an “X” -type structural skeleton with many near-east-west faults superimposed on one another, The formation of a series of Lu Xi by the role of rotation is difficult to set up.