The Meiletu Formation in the northern area of Abagaqi, Inner Mongolia, is NE placement distribution, it ranges to Mongolia along the NE placement. The regional geological survey has assigned it to Erliandabushu Formation one Paragraph (K2e1). Studies show that the formation sould be assign to Meiletu Formation. Rock association is andesite-basalt, basalt, basalt-andesite and pyroxene andesite and so on. K-Ar isotopic age dating of pyroxene andesite whole rock is 122~136 Ma, implying a product of Early Cretaceous magmatic movement.