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北阿尔金恰什坎萨伊沟南口火山岩显双峰式特征,由变玄武岩和变流纹岩组成.地球化学分析表明变玄武岩源自富集地幔,上侵过程中遭受地壳混染,形成于大陆裂谷环境;而变流纹岩与铝质A型花岗岩特征类似,为幔源岩浆底侵下地壳部分熔融成因.变流纹岩锆石LA-ICP-MSU-Pb年龄为749.8±4.6Ma,代表火山岩的喷发年龄,为北阿尔金洋的初始裂解事件提供了时代证据;与北祁连洋初始裂解时代相近,从洋盆的初始裂解时间证明北阿尔金与北祁连同为一个带.“西域板块”新元古代中期岩浆活动与Rodinia超大陆裂解事件密切相关,与扬子板块周缘岩浆活动有相似性,可划分为裂解初期与峰期两个阶段.所发现北阿尔金南华纪双峰式火山岩正是Rodinia超大陆裂解峰期岩浆活动的产物.
The bimodal characteristics of volcanic rocks in the north of the Kanasaiyigou Formation in the North Altyncashu are composed of variable basalts and rhyolitic rocks. Geochemical analyzes show that the basalts originate from enrichment of the mantle and are subjected to crustal contamination during the invasion Continental rift environment, while the rhyolite is similar to that of the aluminum type A granite, and is partly melted by crust beneath the mantle source magma. The LA-ICP-MSU-Pb zircon age of the rhyolite is 749.8 ± 4.6Ma , Representing the eruption age of volcanic rocks, which provided the evidence of the age for the initial pyrolysis of the North Altyn Ocean; similar to the initial pyrolysis of the North Qilian Ocean and from the initial pyrolysis of the ocean basins, the North Altyn and the North Qilian belonged to the same belt. Plate "The mid-Neoproterozoic magmatic activity is closely related to the Rodinia supercontinent cracking event and similar to the magma activity in the periphery of the Yangtze plate, and can be divided into two stages, the initial and the peak period of cracking. The North Arjin South China Bimodal volcanic positive Is the product of the magmatic activity at the peak of the fracture in the Rodinia supercontinent.