Thyon volcanic rocks are classified as alkali basalts, with pyroxene megacrysts, and deep-seated mantle xenoliths such as augite and peridotite have been observed in some basaltic layers.

• 火山岩主要为碱性玄武岩，部分玄武岩中可见橄榄岩类等深源岩石包体和普通辉石等矿物巨晶。