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伊犁石炭纪裂谷叠加在中天山造山带之上．后者是在加里东旋回中发育的造山隆起带，除发育下古生界优地槽沉积外，前寒武系变质基底广泛出露，石炭纪沉积以大小不筹的上叠盆地不整合在这样一个基底之上。由于基底性质的差异，西段盆地范围大，沉积厚度大；向东到巴仑台直至托克逊地区，则呈断续延伸的小型断用盆地，厚度薄，而且底砾岩层的厚度大．现有资料说明，石炭纪火山岩主要是玄武岩一玄武安山岩－粗安岩和粗面岩－流纹岩组合．以碱性系列的岩石为主，多为高钾系列，次为钠质；主要为低Ａｌ型，也有高Ａｌ型；轻稀土和不相容元素从低度富集到中等富集（Ｌａ／Ｙｂ为１．８～６．７和５．３～１４．９），Ｎｂ、Ｔａ从微亏损到强亏损（Ｔｈ／Ｔａ≈１．３～１５）；Ｎｄ（ｔ）值偏低（≈＋２．３～＋４．６），而ＩＳｒ（～０．７０５８）和２０８Ｐｂ偏高（２０８Ｐｂ／２０４Ｐｂ≈３８．４５２，２０６Ｐｂ／２０４Ｐｂ≈１８．３７８），反映其岩浆来自弱富集或异常地幔源区．由于裂谷发育程度的不同，岩浆或者直接来出，或者在下地壳环境下受到混染或发生分异，从而导致岩石组合在走向上的差异。
The Ili Carboniferous rift overlies the middle Tianshan orogen. The latter is a orogenic uplift belt developed in the Caledonian cycle. Except for the development of the Lower Palaeozoic sedimentary system, the Precambrian metamorphic basement is widely exposed. The unconformity of the unconformity of the Upper Carboniferous sediments in the unconformity Above such a base. Due to the differences in basement properties, the western segment of the basin has a large area and a large sedimentary thickness. From the east to the Balunda to the Toksun region, there is a small fault basin extending intermittently, with a thin thickness and a thick basement conglomerate. The available data indicate that the Carboniferous volcanic rocks are mainly basalt-basalt andesite-gabbros and trachyte-rhyolite assemblages. Mainly alkaline series of rocks, mostly high-potassium series, secondary sodium; mainly low-Al, also high-Al; light rare earth and incompatible elements from low to moderate enrichment (La / Yb ranged from 1.8 to 6.7 and from 5.3 to 14.9), Nb and Ta ranged from slight losses to strong losses (Th / Ta≈1.3 to 15), Nd (t) values were low (≈2 .3 ~ +4.6), while ISr (~0.7058) and 208Pb are high (208Pb / 204Pb≈38.452,206Pb / 204Pb≈18.378), reflecting that the magma came from the weakly enriched or anomalous mantle source . Due to the different degrees of rift development, the magma is directly mixed with or disintegrated or differentiated in the lower crust, leading to differences in the direction of rock assemblages.