CAJ | 학술논문

通过对博格达东部下涝坝地区的辉绿岩进行研究，发现该区辉绿岩具富铝、高演化（FM和FL值都较高）、经过壳幔混合或改造（高烧失量）、Y/Ho、Zr/Hf和Nb/Ta的比值显示出非球粒陨石的特点。首次在该区发现了辉绿岩的稀土元素具四分组效应，通过对辉绿岩稀土四分组效应的程度进行量化，发现本区的辉绿岩稀土元素具明显的“MM”型四分组效应，且TE1、3TE1、3、4均大于1.1，表明稀土元素“M”型效应非常明显。认为该地区辉绿岩稀土元素的“MM”型四分组效应是由于辉绿岩的高演化、受到高铝质的地壳改造，及后期挥发分和流体的改造等因素造成。
통과대박격체동부하로패지구적휘록암진행연구，발현해구휘록암구부려、고연화（FM화FL치도교고）、경과각만혼합혹개조（고소실량）、Y/Ho、Zr/Hf화Nb/Ta적비치현시출비구립운석적특점。수차재해구발현료휘록암적희토원소구사분조효응，통과대휘록암희토사분조효응적정도진행양화，발현본구적휘록암희토원소구명현적“MM”형사분조효응，차TE1、3TE1、3、4균대우1.1，표명희토원소“M”형효응비상명현。인위해지구휘록암희토원소적“MM”형사분조효응시유우휘록암적고연화、수도고려질적지각개조，급후기휘발분화류체적개조등인소조성。
This paper focuses on the diabase which is exposed at Xialaoba area of northern Bogeda.The diabase is rich in aluminum and highly evolved (with high FM and FL values), which is due to subsequent alteration or a mixed origin of crustal and mantle materials.The Y/Ho, Zr/Hf and Nb/Ta ratios of the diabase are different from those of chondrites.It is firstly reported that the diabase displays obvious tetrad effect on the chondrite-nomalized REE pattern,as evidenced by high TE1,3 and TE1,3,4 (>1.1).This tetrad effect is ascribed to high-degree evolution of parent magma,contamination of high-aluminum crust and influence of later volatiles and fluids.