华北板块东部石炭纪(竹蜓)带缺失规律及其意义

在欧亚大陆形成过程中,位于西伯利亚和华北板块之间的洋壳曾长期向华北板块之下俯冲消减,致使板块北部不断抬升,(竹蜓)带也呈现有规律地缺失。(竹蜓)带缺失揭示:①华北板块自中石炭世晚期开始抬升,至晚石炭世晚期变华北地势由北、东部低,南、西高(C_2)为北、东部高、南部低;②随着板块北部的不断抬升,海浸中心不断向南迁移,煤层和海相层也由北而南层位逐渐变新;③郯庐断裂以西几乎全部缺失中石炭世早期和中石炭世晚期早时(竹蜓)带,因此,石炭纪华北海浸是中石炭世晚期中时向山西及华北腹地推进的;④(竹蜓)带缺失的相对上升区一般为浅滩相,这是由于华北石炭纪的构造振荡运动振幅小,频率大,而仅表现为海陆环境的频繁交替,并未能脱离沉积盆地环境,故一般不存在沉积间断;⑤石炭纪郯庐断裂活动对这一时期的沉积起了控制作用。

NEW IDEAS ON ABSENT REGULARITY OF FUSULINID ZONES AND ITS SIGNIFICANCE DURING THE CARBONIFEROUS IN EASTERN NORTH CHINA

During the formation of Eurasia,the oceanic crust between Siberian Plate and North China Plate(NCP)had been subducing and consuming towards the floor of NCP so that the northern NCP constantly uplifted with regular absence of Fusulinid zone.The absence of Fusulinid zone results in the following: 1.In the late Mid-Carboniferous(C_2),the northern,eastern NCP were low and southern,western high,while in the late Late-Carboniferous(C_3),the eastern,northern NCP were high and southern low; 2.With the northern NCP continuously uplifting,the centre of transgression had been moving towards the south,while the coal layers and sea facies layers are gradually more new from north to south; 3.Almost all Fusulinid zones between early period of late C_2 absent in the area to the west of Tancheng-Lujiang fault(TLF)system imply the North China transgression in Carboniferous pushed towards Shanxi and the centre North China in the middle period of late C_2; 4.The relatively uplifting area absent Fusulinid zones are generally shoal facies. The Carboniferous osillatory movement was of small amplitude and of high frequency, sea and land enviroments alternated frequently still in the scope of the deposition basin enviroment.So,there are not lacuna; 5.TLF system has controlled the Carboniferous deposition.