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枕状熔岩是海相火山岩的一种特有产出形式，在海相中基性火山岩中普遍发育。基性枕状熔岩往往构成蛇绿岩套的重要组成部分，具有重要的理论研究价值．但在中酸性火山岩中的枕状熔岩则极为罕见，目前仅在我国的白银厂产出有角斑质岩枕（彭礼贵等，１９９５；ＬｉＺｈｉｐｅｉｅｔａｌ，１９９６）．本文较详细地描述了北祁连山西段首次发现的英安质枕状熔岩的产出状态和岩石学特征，并在岩石化学方面与白银厂角斑岩进行对比。认为北祁连山西段英安质枕状熔岩，是海底火山作用发展到岩浆房中的岩浆过剩压小于某一临界值时发生溢流作用（Ｗｏｏｄｓ，Ｗ．Ａ．，１９９５）而喷出的岩浆流所形成．对于英安质岩枕中的富硅包裹体－硅质岩提出的三种可能成因即外来硅质岩团块、杏仁体和岩浆喷发后因物理化学条件的突变所造成的岩浆不混熔液珠，尚需更多的地质、地球化学资料来证实。
Pillow lava is a peculiarly produced form of marine volcanic rocks, which is commonly found in marine volcanic rocks. Basic pillow lava often constitute an important part of ophiolite suite, has important theoretical research value. However, pillow-shaped lava in intermediate-acidic volcanic rocks is extremely rare. At present, only hornblende is produced in our silver plant (Pengli Li et al., 1995; Li Zhipei et al., 1996). This paper describes in more detail the output status and petrological characteristics of the amphibolite-lava hosted in the western section of the northern Qilian Mountains and compares it with the Baiyanchang angular porphyry in petrochemistry. It is considered that the quartzite-hosted pillow lava in the western part of the northern Qilian Mountains is a magma that overflows when submarine volcanoes develop into magma chamber excessively below a certain critical value (Woods, W.A., 1995) Flow formed. For the three possible reasons for the inclusion of silicon-rich inclusions in the amphibolite-quartzite rocks, that is, the immature magmatic clumps, almond bodies and magmatic immiscible fluids caused by sudden changes in physico-chemical conditions after magma eruption Beads, still need more geological, geochemical data to confirm.