Based on the anisotropy of magnetic susceptibility (AMS), the Hannuoba basalt was probably originated from two volcanoes that locate in the northeast and north-northwest directions, respectively which is consistent with the field observation.

• 基于磁化率各向异性测定，推断张北汉诺坝玄武岩是由位于北东和北北西两个方向的古火山口喷发而成，这与野外观察一致。