Abstract:Gulukou area is located in the border of Zoucheng city and Tengzhou city. It belongs to active belt in plate.and is favorable for diamond mineralization. Four diamond excavation sites and one ultrabasic picrite pipe have been found in the area. Through IP sounding and joint profile survey, it is preliminarily concluded that the picrite pipe has the trend of SE with a large dip angle and nearly vertical. As showed by natural heavy sand samples, main heavy minerals are hematite, magnetite, zircon, epidote, metallic spherulite, rutile and so on. The content of garnet is small. The garnet content of two samples is more than 20 grains, and the rest of samples containing garnet are less than 10 grains. Through identification of artificial heavy sand samples, main heavy minerals are chromite diopside, sphalerite, galena, pyrite, magnetite, chromite, etc. As showed by the EPMA analysis of 50 diopside and chromite, they belong to group S5 and group S11, and has indication to diamond prospecting. Through IP middle gradient survey, two abnormal polarizabilities have been delineated, and the abnormal shape is nearly elliptic with the trend of NW. The peak value is more than 2.0. On the plane map of apparent resistivity contour, it is corresponding to the relatively low resistivity area. It is inferred that metal mineralization has increased local apparent polarizability, and decreased apparent resistivity. As showed by prospecting information, there is a primary diamond ore-forming environment in this area. It is easy to carry out the exploration and research of primary diamond ore.
