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Super-magnesium iron mass has been newly discovered in the Liushuquan area at the southern edge of the East Junggar Orogenic Belt in Xinjiang, with a lithographic caste of olivine pyroxene horn amphibolite. The AGE of zircon obtained by LA-ICP-MS zircon U-Pb was (410.9±3.5) Ma, and the formation era was the Early Devonian. The characteristics of petroglyphology show that the main minerals of olivine pyrocite horn amphibolite are horn amphibolite, olivine, monoclinic pyroxene, containing a small amount of orthophopod and oblique feldspar, and the secondary minerals are chromite, spinel, magnetite and so on. The results of the electronic probe analysis show that olivine belongs to the noble olivine series, and the single oblique pyroxene is mainly calcium-rich diopside, the orthophopod is bronze pyroxene, and the horn amphibolite is calcium-magnesium horn amphibolite and magnesium horn amphibolite. Mineral chemical characteristics reveal that the parent magma of the Willow Springs rock mass is a low-degree evolution of high-magnesium labrabra basalt magma, and the mother magma composition has the characteristics of high Mg and Ni, and the magma has a high oxygen escape (△NNO+0.9~△NNO+1.8) and water content (5.1%-7.0%). Comprehensive research suggests that the olivoxene horn amphibolite in the Willow Spring area has the characteristics of Alaskan-type rock masses, and its parent magma is an aqueous high-magnesium lapping basalt magma formed by partial melting of the mantle wedge under the molten fluid of the subduction zone, forming a tectonic environment stretched before the arc, revealing the existence of pre-Devonian crust subduction in the Kalamairi region and experiencing the process of pre-arc expansion and evolution [ABSTRACT FROM AUTHOR]