*3.4.1.3. Intense intrastratal folds and plate-spine breccias*

The strong intrastratal folds occur in the upper part of the Zhuanghuwa section and Yongding River Valley and are about 10–20 cm thick. They are deposited in a very shallow-water depositional environment indicated by the mud cracks and ripple marks beneath this deformed layer.

Plate-spine breccias are widely observed in lamellose or ribbon stripped layers of the Mesoproterozoic in the North China craton. These deformations are formed when the incomplete consolidated laminated layers experience continued compression and completely crack along the axial plane of folds. **Figure 12f** is a superimposed deformation structure of the intrastratal fold and plate-spine breccias, which are formed on two wings of folds, and the top of the fold layer without erosion looks like clouds and is covered by undeformed laminated layers. The formation mechanism of plate-spine breccias may be seismic activities [60]. Ettensohn et al. called the intense folds accordion-like folds, which are induced by earthquakes [34].

## *3.4.2. SSDSs triggered by the paleo-activity of the Shijiazhuang-Lingyuan Fault Belt*

The Yanliao taphrogenic trough is a NE-trending rifting basin in the northern part of North China Craton and is open to the north [63–65]. The Shijiazhuang-Lingyuan Fault Belt (>800 km long) is the main fault belt with the NE-trending (**Figure 12B**), which is extended along the axial part of the Yan-Liao Aulacogen, activated during the early Mesoproterozoic in an extension tectonic environment [63]. The observed SSDSs are mainly distributed approximately less than 20 km from the fault in vertical distances. Identified SSDSs include intrastratal faults, liquefaction sand veins, liquefaction carbonate mounds and volcanos along the paleo-active fault belts. The SSDS layers have been interbedded by the many undeform layers. And some of them have the abnormal geochemical records such as Re, Os, Ir and other rare elements in black silty mudstones or shale of Chuanlinggou Formation that give a clue that volcanic and seismic events existed [77]. The liquefaction carbonate mounds and sand volcanos in the Mesoproterozoic have similar features which induced by the recent Wenchuan earthquake (Ms 8.0) in Sichuan Province, SW China in 2008. According to the mechanism of SSDSs and the relationship of the activity of SSDSs and faults, they may be triggered by paleo-seismic events of the Shijiazhuang-Lingyuan Fault Belts. There are about 29 times deformation layers or seismic event layers have been observed in the Zhuanghuwa section, and the occurrence frequency of the strong paleo-earthquakes is about 20 thousand years to 32 thousand years [78, 79]. Multiple seismic events and activities of the Shijiazhuang-Lingyuan Fault Belt are responded on the break-up of the Columbian supercontinent.
