4 . triangular diagram of the sandstone clastic compositions and the relationship diagram of major element suggest that the proto basin of the clastic rock of the yanbian group was a forearc basin , which was in an active continental margin 鹽邊群碎屑巖碎屑骨架顆粒統(tǒng)計(jì)分析結(jié)果和砂巖常量元素構(gòu)造環(huán)境判斷圖解顯示,它們所處的構(gòu)造環(huán)境為活動(dòng)大陸邊緣,初步判定它們的原型盆地為弧前盆地。