关键词: 二连盆地, 物理模拟, 中生代, 伸展构造, 控制因素

Abstract: The Erlian Basin is a Mesozoic oil-and gas-bearing basin in northeastern China. There are significant geometric and
kinematic similarities between the Erlian Basin and other Mesozoic rift basins in eastern China. According to the tectonic line of the
basin and the structure observed from the typical seismic profiles, the Erlian Basin consists of a central forward rift zone and peripheral
diagonal rift zones. Although a considerable amount of research has been carried out on the pre-tectonic control of the Mesozoic
deformation of the basin, the contemporaneous tectonic controlling factors remain unclear. In this study, three planar sandbox models
were designed to determine the major controlling factors by changing the extension rate, the extension direction, and the
syn-sedimentation. The results showed that the extensional direction controlled the internal fault characteristics of the rift. The ability
of the extension direction to control the fault characteristics increased with distance from the rift boundary. The rate of extension
changed the expansion of the weak tectonic zone and the scale of fracture development. Larger extension rates could lead to a largerand more complex fracture system. The syn-sedimentary action promoted the activity of the underlying slip-off layer, inhibited the
growth of the boundary fault, and thereby reversely promoted the development of internal secondary fractures. The experimental results
also showed that the extension direction was the major controlling factor of the tectonic deformation of the basin. The syn-sedimentation
and extension rate were the secondary controlling factors. Additionally, according to the geometric and kinematic similarity of typical
Mesozoic rift basins in eastern and adjacent areas of China, the study suggested a “southeastward extension” as a possible kinematic
mechanism for the basin.

Key words: Erlian Basin, physical simulation, Mesozoic, extensional tectonics, major controlling factors