Geochemistry characteristics and cause of formation of Jidanping Fm rocks, southern Song county of southern Henan
Abstract：Southern Song county mainly exposes Mesoproterozoic Erathem Xionger group Jidanping Fm interme- diate - acidic explosive rock. The characteristics of petrography and the composition of major elements show that they are rhyolite, dacite rhyolite and andesite. The data of all alkali content ( N%O + K20) of the two samples is below 3.5% , the others are 5.32% ; the average of CaO is 1.21% ; the value of is commonly 0. 89-2.1, which belongs to Calcium alkaline rock types. The characteristics of rare earth element distribution are the enrichment of light rare earth, the weak positive anomaly of Ce and medium negative anomaly of Eu. In the spider diagram of a volcanic rock incompatible element, all the samples have the similar rare earth ele- ment characteristics and enrich the high field intensity element Ba and Rb and loss the low field intensity ele- ment Nb and Sr. In the discriminant figure of Rb-(Y + Nb) and Hf-Rb-Ta, they are mainly located in VAG and WPG, the characteristics of diagenetic environment is intraplate arc ,Jolcanic rocks.
Keywords：volcanic rocktrace elementcharacteristics of geochemistryJidanping formation
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 679-686 )