From 1D to 4D: Advances and thoughts on coal seismic technology

As one of the key technologies for safe and efficient support of coalmine geology, the seismic technology, has gone through one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D), and progressed from resource exploration to mining area exploration, and from structural exploration to lithological exploration. The latest 4D seismic will further leapfrog from static detection to dynamic detection. Based on the concepts of time-space dimensions and the four seismic development stages, we propose three transitional stages from 1.5D (e.g., non-zero offset VSP), 2.5D (e.g., wide line 2D seismic exploration) to 3.5D (e.g., 3D seismic dynamic interpretation), and also present the time-space characteristics of the seven seismic stages, including 1D, 1.5D, 2D, 2.5D, 3D, 3.5D and 4D. Results show that: (1) The increase of coal seismic dimension from low to high, from space to space-time, makes the amount of underground information grow exponentially; the accuracy of solution to geological problems is improved significantly, which is the internal engine of continuous development of seismic technology for coals. (2) The accumulation of fundamental theoretical research, the upgrading of seismic exploration instruments, and the demand of coal mining technologies, are the external driving force for the continuous advancement of seismic technology. (3) The interdisciplinary research and technological integration over multiple disciplines, industries and sectors have accelerated the iteration and upgrading of seismic technology of coal field.