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河西堡花岗岩体为阿拉善地块西南缘早古生代中酸性岩浆活动的产物。其中产出一些闪长岩、石英闪长岩甚至玄武岩的暗色包体，这些包体的岩相学特征暗示它们是曾经与寄主花岗岩处于同一熔融状态的基性岩浆组分的结晶产物。矿物温压计估算的结果表明，包体与寄主岩的再平衡结晶温压条件十分接近。寄主花岗岩的岩石化学、稀土元素及锶同位素组成也表现出基性组分与酸性组分混合的特点。采用Ｃ混＝ＫＣ基＋（１—Ｋ）Ｃ酸混合定量模式估算出基性组分占２０％～４０％。由此表明，阿拉善地块西南缘早古生代早期花岗岩的形成，与同一时期或更早时期的基性、中基性岩浆活动可能有着直接的成因联系。
The Hexi Fort granite is the product of the Early Paleozoic acidic magmatism on the southwestern margin of the Alashan Block. Among them, some dark inclusions of diorite, quartz diorite and even basalt are produced. The petrographic features of these inclusions suggest that they are the crystalline products of the basic magmatic components which have been in the same molten state as the host granite. The results of mineral temperature and pressure gauges indicate that the temperature and pressure conditions of the recrystallization and crystallization of the host rock are very close. The petrochemical, rare earth and strontium isotopic composition of the host granite also shows the mixing of the basic and acidic components. Using C mixed = KC-based (1-K) C acid mixed quantitative model estimated basic components accounted for 20% to 40%. The results show that the formation of early Early Paleozoic granites on the southwestern margin of the Alashan Block may have a direct genetic relationship with the basic and basic mafic activities of the same period or earlier.