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位于大别造山带北部的合肥盆地 ,其中的沉积是造山带剥露历史的重要记录。自生伊利石K -Ar测年 ,证实了合肥盆地中部安参 1井自上而下钻遇了下白垩统 ,上、中、下侏罗统 ,下二叠统和上石炭统地层 ,下伏为奥陶系。中生界砂岩碎屑组分分析 ,表明其源区为大别造山带。安参 1井内下二叠统砂岩不含造山带来源的碎屑多硅白云母。自下侏罗统至下白垩统 ,钻遇的砂岩中连续出现了丰富的碎屑多硅白云母 (Si>3.3)。这不但指示大别造山带是合肥盆地的主要物源区 ,也限定了大别高压 -超高压变质岩在早侏罗世早期就已经剥露地表 ,继而连续出露
Located in the Hefei basin in the northern part of the Dabie orogenic belt, the sediment is an important record of orogenic belts. The authigenic illite K -Ar dating confirmed that the Ansai-1 well in the central Hefei Basin had encountered lower Cretaceous, upper, middle and lower Jurassic, Lower Permian and Upper Carboniferous formations from top to bottom, For the Ordovician Department. Analysis of the Mesozoic sandstone clastic composition shows that the source area is Dabie orogenic belt. The lower Permian sandstone in Ansai-1 well does not contain debris from the orogenic belt. From the Lower Jurassic to the Lower Cretaceous, rich clastic polytrissities (Si> 3.3) appeared successively in the sandstone that had been encountered. This not only indicates that the Dabie orogenic belt is the major source area for the Hefei Basin, but also limited the Dabie UHP-UHP metamorphic rocks that had been exposed to the surface during the early Jurassic and then continuously exposed