Petrographic and element geochemical features show that these plutons are typical S-type granites.

The study of Neoarchean S-type granite,with obvious tectonic significance,which lies in Hejiao area,Darhan Muminggan Lianheqi,Inner Mongolia,in major elements,trace elements and SHRIMP zircon U-Pb geochronology provided further evidence for understanding the nature of tectonic setting of the northern margin of North China plate at the end of Neoarchean.

They are the A-type granites and derived from partial melting of the lower crust in the setting of post-orogenic extension mechanism,The Late Jurassic granite-porphyry and rhyolite-porphyry are similar to S-type granites by their slightly lower silicon,slightly higher aluminum,and high A/CNK ratio,which has great varying range and indicates these rocks are peraluminous.

Monazite age mapping of Longhua S-type granites in the northern margin of the North China Craton.;

In order to verify the presence of residual organic matter in some S type granites,an acid dissolution method for isolating kerogen from sedimentary rocks was employed to deal with samples from the Xihuashan granite body,Jiangxi,and a little black carbonaceous matters were identified with Optical,XRD and SEM/EDAX analyses in the acid insoluble residue.

All the evidence indicate that it have the characteristic of S type granite.