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区域热年代和差异冷却特性表明,140～85Ma大别造山带进入热窿伸展作用时期,由此引发基底广泛熔融、北淮阳剧烈火山喷溢以及合肥盆地断陷等过程.这次热窿事件包括强热伸展阶段（140～105Ma）和晚期衰退阶段（105～85Ma）.在强热伸展阶段,热窿区集中在大别/红安地块,并以大别地块热窿作用最为强烈,某种意义上可将红安地块视为大别热窿翼部.大别热窿构造包括麻城-岳西热轴、穹核组合及其外围翼部,热轴平行造山带延向展布,北淮阳与高压/超高压（HP/UHP）岩石构成下滑翼部,岳西、罗田热窿核分别占据麻城-岳西热轴东、西两端,它们最终成型时代不一致、热窿伸展进程伴随着大别强热中心沿着麻城-岳西热轴迁移摆动,如果将热窿事件与造山带根部拆沉相联系,这种拆沉作用应以间歇性、迁移性、规模性与区域差异性为特征.在伸展衰退阶段（105～85Ma）,大别造山带仍显现穹状热窿布局,但其伸展强度、岩浆活动显著减弱.解析热窿伸展作用,对于认识大别HP/UHP岩折返模型、“南北大别界限”以及造山过程机理具有重要启示意义.
The geothermal age and differential cooling characteristics indicate that the Dabie orogenic belt of 140-85Ma entered the hot-hole extensional period, resulting in extensive melting of the basement, violent volcanic spurt of the North Huaiyang basin and fault depression of the Hefei Basin. Including the intense hot stretch (140 ~ 105Ma) and the late decline (105 ~ 85Ma) .In the intense heat spreading stage, the hot hole is mainly concentrated in the Dabie / Hongan block and the hot hole is the most intense in the Dabie block In a sense, the Hongan block can be regarded as a Dabie hot-wing wing.The structures of Dabie hot-hole include the Macheng-Yuexi thermal axis, the dome combination and its peripheral wings, and the hot axis parallel orogenic belt extends to the extensional Cloth, North Huaiyang and high pressure / high pressure (HP / UHP) rock slide wing, Yuexi, Luotian hot core respectively occupy the Macheng - Yuexi hot axis east and west ends, the final forming of their age inconsistent, hot Along with the migration of Dabie heat center along Macheng-Yuexi hot axis, the process of hole extension is linked with the detachment of the root of the orogenic belt. This kind of detachment should be based on intermittent, migratory, And regional differences characterized by the extension of the recession (105 ~ 85Ma), large The orogenic belt still shows the dome-shaped hot hole layout, but the extensional strength and magmatic activity are significantly weakened.Analyzing the hot stretch extension is of great significance for understanding the reentry model of the Dabie HP / UHP rock, “the Dabie boundary between the South and the North,” and the orogenic process significance.