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中国东部双气囊花粉首次出现于早石炭世末期 ,迄今已有近 3亿年的历史。晚石炭世以来 ,包括松科、罗汉松科、古老松柏粉类、具缝双囊粉类、原始无肋双囊粉类及具肋双囊粉类在内的双气囊花粉 ,在地质发展历史上不仅仅展现为随时间的新老交替过程 ,而且呈现出明显周期性富集现象。 3亿年来 ,双气囊花粉至少存在三个层次的周期性盛衰过程。一级周期时限约 4 5— 5 0 Ma,双气囊花粉往往在其早期阶段富集出现 ,晚期阶段明显衰退。中国东部重要的双气囊花粉富集期包括 :晚石炭世晚期—早二叠世早期、晚二叠世末期—早三叠世早期、晚三叠世末期—早侏罗世早中期、晚侏罗世晚期—早白垩世早期、早白垩世末期—晚白垩世早期、晚白垩世末期—古近纪早期、新近纪中期至更新世。双气囊花粉盛衰过程的二级周期时限约 15— 17Ma,该级周期叠加在一级周期之上 ,并使其复杂化。一般情况下 ,在任意一个一级周期之内 ,前两个二级周期之早、中期阶段 ,双气囊花粉可达到较高的富集程度 ,而第三个二级周期内 ,双气囊花粉往往不甚发育 ,这是由一级周期本身的性质所决定的。双气囊花粉类盛衰过程还存在着超级周期性 ,这种超级周期由两个一级周期组成 ,时限约为 10 0 Ma。地史上 ,此级别周期有 4期 ,其地质时限如下 :石炭纪—中二叠世末期、晚二叠世早期—晚侏罗世初期、晚侏罗世早期—晚白垩世晚期 (马斯特里赫特早期 )、晚白垩世末期至今。在同一超级周期之内 ,两个一级周期转折处双气囊花粉仍占据较突出地位 ,为弱转折所在。不同超级周期之间 ,一级周期转折处双气囊花粉含量急剧衰减 ,且喜热耐干孢粉类型富集出现 ,特化类型分布普遍 ,为强转折所在。双气囊花粉类盛衰过程还明显地与古气候演化、全球构造变动、海平面升降、缺氧沉积发育、以及盆地演化过程之间存在着明显的相关性。这些规律表明 ,全球自然背景演化过程有着统一的机制 ,而双气囊花粉类盛衰历史为发现这些自然背景演化过程基本规律 ,以及探索其演化机制提供了重要线索。
The double balloon pollen in eastern China first appeared in the late Carboniferous, with a history of nearly 300 million years. Since the Late Carboniferous, the double balloon pollens, including Pinaceae, Podocarpaceae, ancient cypress powder, sutural double sachet, original ribless double sac vesicles and ribbed double sac vesicles, Not only on the show as the process of replacement of old and new over time, but also showed a clear cyclical enrichment phenomenon. 300 million years, double balloon pollen at least three levels of cyclical rise and fall of the process. The first-order period is about 45-500 Ma, and double-balloon pollen tends to accumulate in its early stages, with a marked decline in late stages. Important double-balloon pollen enrichment stages in eastern China include late Late Carboniferous-Early Permian, Late Late Permian-Early Triassic, Late Late Triassic-Early Jurassic, mid-late Jurassic Late Log-Early Cretaceous, Early Cretaceous-Late Cretaceous, late Late Cretaceous-Early Paleogene, from Neogene to Pleistocene. Double balloon pollen ebb and flow of the secondary cycle time limit of about 15-17Ma, the level cycle superimposed on the first cycle, and make it complicated. Under normal circumstances, in any one level of the cycle, the first two secondary cycles in the early, mid-stage, double balloon pollen can reach a higher degree of enrichment, and the third secondary cycle, double balloon pollen often Less developed, which is determined by the nature of the primary cycle itself. There are also super-periodicity in the process of the rise and fall of the double-balloon pollen. The super-cycle consists of two first-level cycles with a duration of about 10 0 Ma. Historically, there are 4 cycles of this level, with the following geological intervals: Late Carboniferous - Late Middle Permian, Early Permian - Early Jurassic, Early Jurassic - Late Late Cretaceous Rieter early), late Late Cretaceous so far. Within the same super-cycle, two-stage pollen of two-stage pollen still occupy a prominent position as the turning point of weakness. Between different super-cycles, the pollen content of the double-balloon at the first-order cycle declines sharply, and the enrichment of the hi-heat resistant sporopollen types occurs. The distribution of special types is widespread, which is a strong turning point. The process of double balloon pollen up-and-down is also clearly related to paleoclimate evolution, global structural changes, sea-level rise and fall, the development of anoxic sediments, and the evolution of the basin. These laws indicate that there is a unified mechanism for the evolution of the global natural environment. However, the history of the rise and fall of the double-balloon pollen class provides important clues for discovering the basic laws of the evolution of these natural backgrounds and exploring their evolution mechanisms.