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出露于扬子北缘大洪山地区的打鼓石群是扬子地区保留比较完整的中元古代地层,其上被青白口系花山群不整合覆盖。通常认为其与神农架群时代相当,但缺乏物源及同位素地质年代学证据。首次报导了打鼓石群底部太阳寺组砂岩的碎屑锆石U-Pb年龄。测年结果显示,该砂岩中碎屑锆石最古老的年龄为3.1~3.2Ga,最年轻年龄为1124Ma,并在2.65Ga和2.75Ga出现统计峰值,且年龄组成与崆岭杂岩区和杨坡杂岩区的多期岩浆活动具有较好的可比性。而鄂西地区神农架群沉积于1.1~1.4Ga,主要统计峰值年龄为1.6Ga、2~2.1Ga、2.7~2.8Ga。因此,打鼓石群沉积时间晚于神农架群,两者非同物异名。
The Taosuqu group, exposed in the Dahongshan area on the northern margin of the Yangtze River, is a relatively intact Mesoproterozoic formation preserved in the Yangtze area and covered by the unconformity of Huashan Group in Qingbaikou System. It is generally considered to be comparable with the Shennongjia Group era but lacking provenance and isotopic geochronological evidence. For the first time, the detrital zircon U-Pb ages of the Taiyangsi Formation sandstone at the bottom of the Taiguogroup were reported. The results of dating show that the oldest age of detrital zircons in this sandstone is 3.1 ~ 3.2Ga, the youngest is 1124Ma, and statistical peaks occur at 2.65Ga and 2.75Ga, and the age composition is similar to that of the Yuling complex and Yang The multi-period magmatism in the plutonic area is well comparable. The Shennongjia group in western Hubei is deposited at 1.1 ~ 1.4Ga with the main statistical peak ages of 1.6Ga, 2 ~ 2.1Ga and 2.7 ~ 2.8Ga. Therefore, the drum rock group deposition Shennongjia later than the group, both non-synonym.