中文摘要：

在新近纪初期（约23 Ma）的时候,在当时中国大陆周边板块构造环境没有发生重大变化的情况下,华北克拉通东部构造活动性质仍发生了明显的变化。比如,华北克拉通东部的岩石圈增厚了,唐山—邢台断裂开始活动的同时太行山山前断裂却变得不活跃了,华北局部构造变形性质发生了变化等。虽然在古近纪和8 Ma以后,有证据显示印度-欧亚大陆的碰撞及其所导致的青藏高原的隆升扩展对华北在水平方向的动力影响占有重要的地位,但这种水平动力作用在整个新生代明显弱于太平洋俯冲板片在垂直方向上对华北东部岩石圈的破坏,甚至在8~23 Ma之间前者对华北的影响在水平方向也不占主导地位。太平洋板块的运动在47 Ma发生重要的变化。如果以这个时间之后的太平洋板块西向俯冲来开始分析,我们会发现太平洋俯冲板片在俯冲运动约20 Ma后（约27 Ma时）就到达了华北东部之下,并在此时板片应被完全破坏。在板片运动过程中,低温板片由于不断被加热和改造,其自身演化具有一定的阶段性,在不同的阶段可以对上覆软流圈和岩石圈产生不同程度的改造。这个阶段性不但在时间上与华北克拉通东部（尤其是华北盆地）新近纪以来发生的构造活动变化基本对应,甚至也与日本海在8~23 Ma扩张的时间基本对应;同时板片在不同演化阶段所能产生的对上覆软流圈和岩石圈的作用也可以合理地对后两者进行解释。因此,太平洋俯冲板片对华北可能产生的由下而上的影响可能是控制华北东部在新生代构造演化的主要因素,甚至在8~23 Ma之间这种影响产生的效果在水平方向也占据了主导地位。

英文摘要：

In spite of tectonic-plate environments surrounding the Chinese continent having no obvious variation in the recent about 40 Ma,the tectonic activities in the eastern North China Craton in the Neogene showed obvious difference with those in the Paleogene.For example,regional lithosphere seems to be thickened,Tangshan-Xingtai faults became active,but the activities of the Taihangshan Piedmont faults reduced.Some evidences showed that the dynamical effects caused by the uplift and extending of the Tibetan plateau which is often attributed to the Indo-Euarasin collision controlled the dynamics of North China in horizontal direction in the Paleogene,and in the time after about 8 Ma,however,the influences and reformations caused by the extending are weaker than the vertical reformation of eastern North China attributed to the Pacific plate subduction beneath the Asian continent;the former was less important even in the period of 8-23 Ma in the horizontal direction than the latter.Previous studies showed that the Pacific plate movement underwent some obvious changes at about 47 Ma.If we only consider the Pacific plate subduction just since this time,we could find that the subduction slab can reach eastern North China after about 20 Ma（at about 27 Ma ago）,and the slab may have been destructed completely at this position.In the 20-Ma-movement processes,the evolution of the cold slab could be divided into several stages with the slab being heated and destructed.In different evolution stages,the slab also could result in different effects on the overlying asthenosphere and lithosphere.The slab evolution showed some temporal consistence with the tectonic activities in eastern North China,and also with the Japan Sea opening.Furthermore,the possible effects acted on the overlying lithosphere by the slab in different stages could interpret the tectonic events mentioned above.Thus,the bottom-up effects attributed to the Pacific subduction mainly controlled the evolution of eastern North China in the Cenozoic,and they are al