The radiolarian siliciliths of the Lower Permian Gufeng Formation inJiangsu-Anhui Region are composed of well-preserved radiolarian and siliceoussponge bodies. Radiolarians are mainly Flustrella and Lithapium

the contentis generally more than 60%

and in some places even up to 80%. The alternationof the mudstone

shale and pyroclastic rock associated with radiolarian silici-liths are characterized by containing plenty of ferromanganese concretion

lackingshallow-water organisms and devoid of carbonate. This is similar with presentdeepsea sediments. According to paleomagnetic analysis

this region used to be nearthe equator during the Early Permian

and this condition fits in the distributionof deep-sea radiolarian ooze in present equator. All these said above show thatthe s?liciliths were formed in deepsea and distributed in deep trough resultedfrom rift faulting.