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北秦岭—南祁连位于我国著名巨型纬向造山带的中段，是以寒武—奥陶纪时期为主形成的裂谷造山带。它经历了板内大陆裂谷→陆间裂谷→火山弧→造山带的开合过程。寒武纪拉张形成碱性、拉斑玄武岩系列及小洋盆蛇绿岩套，奥陶纪闭合形成钙碱性与钾玄岩系列中酸性火山岩及火山弧岩套，并见高镁安山岩。南祁连为单裂谷，北秦岭为双裂谷。北秦岭裂谷从东到西，拉张速度和距离变小，闭合速度变大，火山爆发强度及火山岩的酸度、钾量、壳源组分也顺序增大。其拉张距离与红海型相似，而闭合速度近似安第斯型。古地幔以多种类型叠加为特征，曾有过先强烈亏损，后又富集的过程。从大别山→北秦岭→南祁连→柴北缘纬向对比可知：本区的基性与酸性火山岩浆，分别为地幔与地壳部分熔融形成；中性岩主要为基性岩浆ＡＦＣ作用产物。从东到西，裂谷依次张开，火山喷发时代逐渐变新，拉张速度和距离变大，闭合速度也变大，从而火山岩的碱度变小，蛇绿岩套从无到有。古地幔由ＤＭＭ与ＥＭⅠ混源为主，变为ＤＭＭ与ＥＭⅡ混源为主。
North Qinling - South Qilian is located in the middle of China’s famous giant zonal orogenic belt, is the Cambrian - Ordovician period mainly formed rift orogen. It experienced intraplate continental rift → land rift → volcanic arc → orogenic belt opening and closing process. Cambrian strata formed alkaline, tholeiite basalt series and small-scale pebble ophiolite sets, and Ordovician closed to form acidic-alkaline volcanic rocks and volcanic arc-sets in the calc-alkaline and potash-type rocks. South Qilian single rift, North Qinling double rift valley. North Qinling rift from east to west, stretching speed and distance smaller, closing speed becomes larger, volcanic eruption intensity and volcanic acidity, potassium, shell components also increased. Its stretching distance is similar to that of the Red Sea, while the closure speed is similar to the Andean type. Paleo-mantle is characterized by various types of overlay, and there was a process of first intense loss followed by enrichment. From the latitudinal comparison between the Dabie Mountains → North Qinling → South Qilian → North Qaidam we can see that the basic and acidic volcanic magmas in this area are partially melted by the mantle and the crust, respectively. The neutral rocks are mainly the product of AFC of basic magmas. From east to west, the rifts turn on in turn, and the era of volcanic eruption becomes gradually new. The tension speed and distance become larger, and the closing speed also becomes larger. As a result, the alkalinity of volcanic rocks becomes smaller and the ophiolite sets rise from scratch. The paleo-mantle is dominated by mixed sources of DMM and EMⅠ, becoming the mixed source of DMM and EMⅡ.