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大别地块北缘、合肥盆地南缘的侏罗系凤凰台组()底部冲积扇砾岩中发现花岗岩类砾石, 占砾石体积的5%~10%. 对精选出的两个花岗岩砾石样品中钾长石、黑云母、角闪石和全岩进行Rb-Sr同位素测定, 利用等时线定年方法计算, 获得(428±20)和(430±54) Ma两个年龄, 表明侏罗纪大别山物源区曾发育早古生代花岗岩类岩浆侵入岩. 根据岩石地球化学分析判别它们具有碰撞后隆升花岗岩的成因特征.
On the northern edge of the Dabie block, granite gravel is found in the bottom alluvial fan conglomerates of the Jurassic in the southern margin of the Hefei Basin, accounting for 5% -10% of the volume of the gravel. The two selected granite gravels Rb-Sr isotopic measurements of K-feldspar, biotite, amphibole and whole rock in the samples were used to calculate the ages of (428 ± 20) and (430 ± 54) Ma using the isochronometric dating method, indicating that the Jurassic The Early Paleozoic granitic magmatic intrusions have been developed in the provenance area of the Dabie Mountains, and they are distinguished from the genesis of post-collision uplifted granites according to their geochemical analysis.