Sedimentary Environment of the Late Cretaceous Chishan Formation in the Jiangsu Province
-
摘要: 本文对赤山组创名剖面的岩相及沉积环境进行了详细研究。赤山组为典型内陆盆地沙漠环境沉积物,具较复杂的层序结构,其下段主要为沙漠湖或干盐湖沉积,上段为风成沙丘沉积。对上段风成沙丘沉积系统内的不同级别边界面的特征及成因进行了描述分析;探讨了赤山组沉积的构造背景,认为是在干热气候条件下,苏北盆地已从断陷转为拗陷并逐渐封闭时的沉积物。Abstract: The sedimentological analysis of the Chishan Formation is the result of the detailed, bed-by-bed study of the standard pro-file of Chishan Formation in Chishan Mountain, Jurong County, Jiangsu. Considering lithologies are diverse and according to thegenetic type, six recurring lithophases are distinguished as follows:Lithophase 1 .Purplish red fine calcareous feldspathic graywacke.Lithophase 2. Purplish red fossiliferous calcareous clay siltite or silty claystoneLithophase 3: rPurplish red thin bedded silty clay dolomite (or dolomitic fine-silty sandstone) with polygonal fracture.Lithophase 4. Bricky red fine feldspathic quartz sandstone with large-scale and high-angle cross-bedding.Lithophase 5. Purplish red thick bedded medium-fine feldspathic quartz sandstone with plane bed lamination, intercalatingmuddy flate gravel conglomerate and thin bedded gravelstone.Lithophase 6. Bricky red lenticular unequigranular graywacke, fine feldspathic quartz sandstone and silty claystone,whichconsist of hemicycles with fining-upward grain size.The Chishan Formation can be subdivided into two members. The lower member consists dominantly of lithophases 1,2 and3 which make up hemicycles. The upper member is mainly composed of lithophases 4,6. According to the features of the sedimen-tary structure and texture and lithophase associations of Chishan Formation, the sedimentary environment of the lower member isexplained the desert lake or playa and the upper member interpreted aeolian desert sea.In this paper, it is discussed that the bounding surfaces within the aeolian sandstones with large scale and high-angle cross-bedding (lithophase 4), discribed the sedimentary characteristics of the first-order surfaces (Stokes surfaces) and inquired intothe depositional tectonic setting of the Chishan Formation. We consider that the Late Cretaceous Chishan Formation formed duringthe periods from slowly thermal cooling subsidence to shrinking of the Subei Basin.
-
Key words:
- sedimentary environment /
- Chishan Formation /
- Late Cretaceous /
- Jiangsu
-
[1] 刘季辰,赵汝钧江苏地质志,地质专报,甲种四号,1924 [2] 何俊德,杨恒仁,袁佩鑫.江苏句容赤山赤山组的介形类.古生 物学报,1981,20(4),341-348 [3] 王水,黄仁金等江苏地区白奎纪和新生代轮藻化石.北京:地质出版社,1982,1-66 [4] 王振,袁佩鑫,赵正忠.赤山组及轮藻化石.古生物学报,1983, 22(5):493-503 [5] 吴其切,胡存礼等.江苏及邻区中生代陆相生物地层、沉积相和油气特征.中国地质科学院南京地质矿产研究所所刊.增刊第 二号,1986,50-66 [6] 江苏省地质矿产局.江苏省及上海市区域地质志.北京:地质出版社,1984,299-301 [7] 江苏省地质矿产局.宁镇山脉地质志,南京:江苏省科学技术出 版社,1989,161-162 [8] 陈华成,吴其切等.长江中下游地层志,合肥:安徽省科学技术出版社,1989,533-584. [9] 陈荣林.苏南上白圣统风成砂初探.石油实验地,1982,4(3): 220-224. [10] 张国栋等.从小河口露头区晚白蟹世至早第三纪沉积相特征看苏北盆地早期演化过程.岩相古地理文集(2),北京:地质出版社,1986,192-211. [11] 康育义等苏北盆地西部下第三系的划分和对比地层学杂志,1982,6(1):9-19 [12] 王全金苏北盆地泰州组、阜宁组一段的时代及接触关系.苏北盆地泰州组、阜宁组一段地层古生物.南京大学出版社. 1989.1-32 [13] Brookfield, M. E.,The origin of bounding surfaces in ancientaeolian sandstones, Sedimentology, 1977, 24:303-332. [14] Kocurek, G.,Significance of interdune deposits and boundingsurfaces in aeolian dune sands, Sedimentology, 1981a, 28:753-780. [15] Kocurek, G.,First-order and super bounding surfaces in eoliansequences一bounding surface revisited, Sedimentary Geology,1988, 56:193-206. [16] Stokes. W . L.,Multiple parallel-truncation bedding planes-a feature of wind deposited sandstone, J. Sedim. Petrol.,1968, 38:510-515. [17] Fryberger, S. G.,Schnek, C.J.&Krystinik, L. F.,Stokessurfaces and effecu of near-surface groundwater-table on aeo-lian deposition, Sedimentology, 1988, 35:21-41. [18] Havholm, K. G.,Blakey, R. C. et ;1.,Correlation and signifi-cance of super bounding surfaces, eolian Jurassic Page Sand-stone, Colorado Plateau, USA. In: Aeolian Sediments; Ancientand Modem (Ed.by K. Pye and N. Lancaster), Spec. Pub.int. Ass. Sediment.,1993, 16:87-107. [19] Havholm, K. G. and Kocurek, G.,Factors controlling aeoliansequence stratigraphy: clues from super bounding surface fea-tures in Middle Jurassic Page Sandstone, Sedimentology, 1994,41:913-934. [20] Frakes, L. A.,Climates throughout geologic time, Elsevier,New York, N. Y. pp310. [21] Rea, D. K. and Janecek, T. R.,Late Cretaceous history of so-lian deposition in the Mid一Pacific Mountains, central north Pa-cific Ocean, Palaeography, Palaeoclimatology, Palaeoecology,1981, 36:55-57. [22] Yan Chen, et al.,The configuration of Asia, Prior to the colli-sion of India; Cretaceous paleomagnetic constraints, J. Geo-phys. Res.,1993, 98(B12);21927-21941. [23] 江新胜,李玉元。中国中东部白里纪沙漠的时空分布及其气候意义.岩相古地理,1996,16(2);42-51. [24] 龚与观,孔庆玉.苏北淮安凹陷白蛋系浦口组成盐条件的讨论.石油实验地质.1989,11(2):136-1430.
计量
- 文章访问数: 600
- HTML全文浏览量: 8
- PDF下载量: 676
- 被引次数: 0