Are Those Mafic Dikes In Hengshan Of Shanxi-Xuanhua Of Hebei-Xinghe Of Inner Mongolia Sanukitoids?

In previous study,those mafic dykes in Hengshan,Xuanhua,Xinghe have been thought as the production of intraplate rifting;Some papers have already claimed that some of those so-called mafic dikes may be sanukitouids.So,the definition of those mafic dykes is of important significance for us to distinguish the tectonic background in this area,subduction or extensional tectonic background.The mafic dikes in Hengshan and Xuanhua both have typical ophitic texture through hand specimen.The mafic dikes samples in Hengshan are made up of plagioclase,hornblende,clinopyroxene,garnet and little orthopyroxene,and other accessory minerals,garnet and plagioclase formed symplectite,hornblende and clinopyroxene formed symplectite;the mafic rocks in Xuanhua consist of orthopyroxene,clinopyroxene,plagioclase,hornblende and garnet,and other accessory minerals,without obvious ophitic texture;and those from Xinghe consist of andesine,amphibole,and other accessory minerals,Hastingsite and hornblende formed symplectite,have typical ophitic texture.Compared with the standard of sanukitoids,the main elements of these samples from Hengshan-Xuanhua just meet those terms,but are rich in Fe O* and Ti O2,lightly rich in both compatible elements and incompatible ones.What's more,light rare earth elements are much more than heavy rare earth elements.Otherwise,the samples from Xinghe are very different from the sanukitoids in very low values of Mg#,rich incompatible element other than compatible element.Therefore,those mafic dikes in our working area are not typical sanukitoids but belong to the rock-ferrobasalts,which might have experienced fractional crystallization in some degree,been contaminated by crust,and been likely produced by intraplate rifting.