1) Since the late Paleozoic, the dominant structural system controlling Songliao area is the Neocathaysian structural system, and the main fault zone in the northeast direction controls the sedimentary evolution of Carboniferous-Permian and Mesozoic-Cenozoic.
2) The stage and inheritance of tectonic system evolution are very obvious. For example, the banded tectonic system and Cathaysian tectonic system mainly developed in Archean-Late Paleozoic. The Neocathaysian tectonic system in Songliao area is very obvious in three evolution stages (C-P, J-K 1, K2-Q). For example, the NNE Nenjiang-Kailu fault in the western margin of Songliao Basin has obvious tectonic activity every time, and its active position is basically unchanged.
3) Yanshan movement in Songliao region is the strongest tectonic movement (J3 -K 1) since the late Paleozoic, characterized by rifting and depression in the whole region, with strong magmatic activity. The NE-trending fault zone produced in this period controlled the Mesozoic-Cenozoic sedimentary evolution.
4) In the evolution of tectonic system, the migration of tectonic activities is very obvious. ① Characteristics of sedimentary migration during the late Cretaceous depression, such as the sedimentary center of Nen-2 member in the middle period was in the central and western regions, but it moved to the west at the end; ② Mesozoic volcanic rocks are strong in the west and weak in the east. Modern volcanic rocks are developed in Songliao basin and its east, but the intensity of volcanic activity in the east is obviously weakened. The above characteristics show that the formation time of volcanic rocks in Songliao basin and its eastern region lags behind that in Daxing 'anling region by about 15.20Ma, indicating that volcanic activity migrated from Daxing 'anling region to Songliao basin region, and its intensity gradually weakened. The temporal and spatial distribution characteristics of Mesozoic volcanic rocks in Northeast China also reflect the trend of evolution from west to east and weakening in intensity.
Combined with the Tamulangou Formation in Manzhouli area in recent years (Zhang et al., 2007; Wang et al., 2007), Zalute Al-Al (Ge, 2007), Xinglonggou Formation (Gao, 2004), Manketou Obo Formation and Manitu Formation of Liaoxi Formation (Xu Gang et al., 2005) obtained a batch of zircon U-Pb with the age of163 ~/kloc-0. Volcanic rocks in western Liaoning 156 ~ 145 Ma are consistent with sedimentary rock interlayers containing a large number of late Jurassic fossils. The volcanic rocks in the lower part of the East Gobi Basin in Mongolia also have a 40Ar/39Ar age of (155 1) Ma (Graham et al., 200 1). Current research shows that volcanic rocks larger than 140Ma are only distributed in the west of Songliao basin and the south of Mongolia-Okhotsk belt. All these evidences further support the understanding that Mesozoic volcanic activity began in the west and gradually moved eastward in the late Jurassic. The temporal and spatial distribution characteristics of volcanic rocks in Figure 2. 18 also clearly show this rule.
Fig. 2. 18 distribution map of Mesozoic volcanic rocks