Depositional Environments of the Bedrock of Danxia Landform in Xiangshan Geopark of Jiangxi Province, SE China

doi:10.19657/j.geoscience.1000-8527.2018.02.05

Abstract

Abstract:

Owing to the rise of tourism geoscience and the requirement of geoscience popularization, the research of redbeds and Danxia landform is attracting more and more attention. The Xiangshan Geopark of Guixi City in northeastern Jiangxi Province is featured by the prominent reddish cliffs. The bedrock of the Danxia landform is the conglomeratic strata of the Late Cretaceous Hekou Formation of the Guifeng Group, which is characterized by erosional bases, graded beddings and cross beddings. The sedimentary structures are useful to interpret depositional environments. A detailed centimeter-scale outcrop section was measured to describe lithofacies. Moreover, two conglomerate outcrops were chosen to perform pebble counting. In the measured 40-meter-thick stratigraphic column of the Hekou Formation, seven lithofacies were distinguished: normal graded conglomerate (facies A), inverse graded conglomerate (facies B), structureless conglomerate (facies C), parallel bedding conglomerate (facies D), cross bedding conglomerate (facies E), concentrated conglomerate (facies F), and sandstone (facies G). Clast sizes are mainly 2 cm to 5 cm, although it can range from 0.5 cm to 12.5 cm. Clasts are poorly rounded and moderately weathered. They are composed dominantly of tuff (58%-66.5%) with minor quartzite, granite, and sandstone, which is indicative of the dominant sediment derivation from the Early Cretaceous volcanic-intrusive complex outcropped along the southern margin of the basin. Based on the measured section and pebble counting, the alluvial fan depositional system is envisaged for the formation of the redbeds of the study area. The sediment increments were produced by the combination of faulting along the basin margin with episodic strong rainfalls and transported by braided streams on the alluvial fan lobes. As a result, the frequent interstratification of the conglomerate and sandstone beds, erosions, prevalent fining-upward units were preserved in the outcrops. In addition, under an overall arid climate regime during Late Cretaceous in Southeastern China, the stream-dominated alluvial fan systems were indicative of a climate change towards greater humidity which possibly resulted in abundant streams transporting coarse sediments to the basin area.

Key words: Danxia landform, depositional environment, alluvial fan depositional system, continental redbed, Northeastern Jiangxi Province

CLC Number:

P512.2

LIU Xin, CHEN Liuqin, LI Xinmin, LI Yuliang. Depositional Environments of the Bedrock of Danxia Landform in Xiangshan Geopark of Jiangxi Province, SE China[J]. Geoscience, 2018, 32(02): 260-269.

Figures/Tables 6

References 39

[1]	陈国达, 刘辉泗. 江西贡水流域地质[J]. 江西地质汇刊, 1939(6):1-64.
[2]	黄进. 丹霞地貌坡面发育的一种基本方式[J]. 热带地貌, 1982, 3(2):107-134.
[3]	YOUNG R W, WRAY R A L, YOUNG A R M. Sandstone Landforms[M]. Cambridge: Cambridge University Press, 2009: 1-304.
[4]	彭华, 潘志新, 闫罗彬, 等. 国内外红层与丹霞地貌研究述评[J]. 地理学报, 2013, 68(9): 1170-1181. DOI
[5]	黄进. 丹霞山地貌[M]. 北京: 科学出版社, 2010:1-10.
[6]	郭福生, 李晓勇, 姜勇彪, 等. 龙虎山丹霞地貌与旅游开发[M]. 北京: 地质出版社, 2012: 1-105.
[7]	赵汀, 赵逊, 彭华, 等. 关于丹霞地貌概念和分类的探讨[J]. 地球学报, 2014, 35(3): 375-382.
[8]	朱诚, 马春梅, 张广胜, 等. 中国典型丹霞地貌成因研究[M]. 北京: 科学出版社, 2015: 1-348.
[9]	PENG H, REN F, PAN Z X. A review of Danxia landforms in China[J]. Zeitschrift Für Geomorphologie, 2015, 59 (Suppl.1): 19-33.
[10]	齐德利, 颜明, 闫丹, 等. 中国丹霞地貌的面积概算——粤北坪石红层盆地的实证研究[J]. 山地学报, 2016, 34(2):134-141.
[11]	江西省地质矿产局. 江西省岩石地层[M]. 武汉: 中国地质大学出版社, 1997:1-50.
[12]	江西省地质调查院. 中华人民共和国区域地质调查报告(1∶250 000):上饶市幅[R]. 南昌: 江西省地质调查院, 2002.
[13]	江西省地质矿产局. 江西省区域地质志[M]. 北京: 地质出版社, 1984:1-20.
[14]	陈丕基. 晚白垩世中国东南沿岸山系与中南地区的沙漠和盐湖化[J]. 地层学杂志, 1997, 21(3): 203-213.
[15]	吴因业, 冯荣昌, 岳婷, 等. 浙江中西部永康盆地及金衢盆地白垩系冲积扇特征[J]. 古地理学报, 2015, 17(2): 160-171.
[16]	陈留勤, 郭福生, 杨庆坤, 等. 江西永丰—崇仁盆地晚白垩世沉积体及其演化模式[J]. 山地学报, 2015(4): 416-424.
[17]	CHEN L Q, STEEL R J, GUO F S, et al. Alluvial fan facies of the Yongchong Basin: Implications for tectonic and paleoclimatic changes during Late Cretaceous in SE China[J]. Journal of Asian Earth Sciences, 2017, 134: 37-54. DOI URL
[18]	郭福生, 朱志军, 黄宝华, 等. 江西信江盆地白垩系沉积体系及其与丹霞地貌的关系[J]. 沉积学报, 2013, 31(6): 954-964.
[19]	KRAUS M J, WOODY D T, SMITH J J, et al. Alluvial response to the Paleocene-Eocene thermal maximum climatic event, Polecat Bench, Wyoming (U.S.A.)[J]. Palaeogeography, Palaeoclimatology, Palaeoecology, 2015, 435: 177-192. DOI URL
[20]	SHU L S, ZHOU X M, DENG P, et al. Mesozoic tectonic evolution of the southeast China block: New insights from basin analysis[J]. Journal of Asian Earth Sciences, 2009, 34(3): 376-391. DOI URL
[21]	CHEN L Q, GUO F S. Upper Cretaceous alluvial fan deposits in the Jianglangshan Geopark of Southeast China: implications for bedrock control on Danxia landform evolution[J]. Journal of Mountain Science, 2017, 14(5): 926-935. DOI URL
[22]	CHEN L Q, GUO F S, STEEL R J, et al. Petrography and geochemistry of the Late Cretaceous redbeds in the Gan-Hang Belt, Southeast China: implications for provenance, source weathering, and tectonic setting[J]. International Geology Review, 2016, 58(10): 1196-1214. DOI URL
[23]	江西省地质局区域地质调查大队. 中华人民共和国地质图(1∶200 000):上饶幅[R]. 南昌: 江西省地质局区域地质调查大队,1979.
[24]	江西省地质局区域地质调查大队. 中华人民共和国地质图(1∶200 000):广丰幅[R]. 南昌: 江西省地质局区域地质调查大队,1982.
[25]	地质部江西省地质局区域地质测量大队. 中华人民共和国地质图(1∶200 000):东乡幅[R]. 南昌: 地质部江西省地质局区域地质测量大队,1963.
[26]	NEMEC W, STEEL R J. Alluvial and coastal conglomerates-their significant features[M]// KOSTERE H, STEELR J. Sedimentology of Gravels and Conglomerates. Calgary: Canadian Society of Petroleum Geologists, 1984:1-31.
[27]	KALLMEIER E, BREITKREUZ C, KIERSNOWSKI H, et al. Issues associated with the distinction between climatic and tectonic controls on Permian alluvial fan deposits from the Kotzen and Barnim Basins (North German Basin)[J]. Sedimentary Geology, 2010, 223: 15-34. DOI URL
[28]	钱程, 韩建恩, 余佳, 等. 山西榆社盆地新近系马会组砾岩层砾组特征及其地质意义[J]. 现代地质, 2011, 25(4): 778-788.
[29]	陈留勤, 郭福生, 梁伟, 等. 江西抚崇盆地上白垩统河口组砾石统计特征及其地质意义[J]. 现代地质, 2013, 27(3): 568-576.
[30]	CHEN L Q, GUO F S, TANG C. Evolution of the Late Cretaceous Yongfeng-Chongren Basin in Jiangxi Province, southeast China: insights from sedimentary facies analysis and pebble counting[J]. Journal of Mountain Science, 2016, 13(2): 342-351. DOI URL
[31]	BRIDGE J S. Fluvial facies models: Recent developments[M]//POSAMENTIER H W, WALKER R G. Facies Models Revisited. Tulsa:SEPM, 2006: 85-170.
[32]	MIALL A D. A review of the braided-river depositional environment[J]. Earth Science Reviews, 1977, 13(1): 1-62. DOI URL
[33]	JO H R, RHEE C W, CHOUGH S K. Distinctive characteristics of a stream flow-dominated alluvial fan deposit: Sanghori area, Kyongsang Basin (Early Cretaceous), southeastern Korea[J]. Sedimentary Geology, 1997, 110: 51-79. DOI URL
[34]	BLAIR T C, MCPHERSON J G. Processes and forms of alluvial fans[M]// PARSONSA J, ABRAHAMSA D. Geomorphology of Desert Environments. Washington: Springer, 2009: 413-467.
[35]	JULLIEN R, MEAKIN P, PAVLOVITCH A. Three-dimensional model for particle-size segregation by shaking[J]. Physical Review Letters, 1992, 69(4): 640-643. PMID
[36]	SOHN Y K, RHEE C W, KIM B C. Debris flow and hyperconcentrated flood-flow deposits in an alluvial fan, northwestern part of the Cretaceous Yongdong Basin, Central Korea[J]. Journal of Geology, 1999, 107(1): 111-132. DOI URL
[37]	BLAIR T C, MCPHERSON J G. The trollheim alluvial fan and facies model revisited[J]. Geological Society of America Bulletin, 1992, 104: 762-769. DOI URL
[38]	KRAUS M J, MCINERNEY F A, WING S L, et al. Paleohydrologic response to continental warming during the Paleocene-Eocene Thermal Maximum, Bighorn Basin, Wyoming[J]. Palaeogeography, Palaeoclimatology, Palaeoecology, 2013, 370(2): 196-208. DOI URL
[39]	HASEGAWA H, TADA R, ICHINNOROV N, et al. Lithostratigraphy and depositional environments of the Upper Cretaceous Djadokhta Formation, Ulan Nuur Basin, southern Mongolia, and its paleoclimatic implication[J]. Journal of Asian Earth Sciences, 2009, 35(1): 13-26. DOI URL

类型	名称	层厚/cm	沉积构造或特征	成因解释
岩相A	正粒序砾岩	10~60	底侵蚀界面,正粒序层理	反映洪水泛滥事件引起的水流能量由高到低的变化。底侵蚀界面指示了高能水流对早期沉积物的侵蚀作用
岩相B	逆粒序砾岩	5~60	底侵蚀界面,逆粒序层理	在分散压力和动力筛选作用下,颗粒间互相碰撞导致较粗的砾石向上运动
岩相C	无沉积构造砾岩	10~40	不发育沉积构造,砾石可呈线状排列	富砂碎屑流在快速沉积作用下形成的近源沉积,沉积物来不及分选
岩相D	平行层理砾岩	30~110	平行层理	在快速迁移的、宽而浅的河道环境,或是在冲积扇下游的非河道化泛滥作用
岩相E	交错层理砾岩	15~60	槽状、板状交错层理	板状交错层理主要是在低流态条件下,由大的直脊波纹和沙丘迁移形成的,而槽状交错层理是由小型水流波纹迁移形成的
岩相F	聚集状砾岩	10~20	颗粒支撑的砾石,不显示粒序变化	片流或越岸流体将沉积物表层的细粒组分带走,而剩下粗粒碎屑颗粒聚集形成筛状沉积
岩相G	砂岩	< 40	常与下伏砾岩层渐变构成向上变细的沉积旋回,或呈透镜层状夹于砾岩层之间	以粗砂岩为主,少量为中砂岩,多含有砾石。顶界面为被上覆砾岩下切侵蚀而成的冲刷面

类型	名称	层厚/cm	沉积构造或特征	成因解释
岩相A	正粒序砾岩	10~60	底侵蚀界面,正粒序层理	反映洪水泛滥事件引起的水流能量由高到低的变化。底侵蚀界面指示了高能水流对早期沉积物的侵蚀作用
岩相B	逆粒序砾岩	5~60	底侵蚀界面,逆粒序层理	在分散压力和动力筛选作用下,颗粒间互相碰撞导致较粗的砾石向上运动
岩相C	无沉积构造砾岩	10~40	不发育沉积构造,砾石可呈线状排列	富砂碎屑流在快速沉积作用下形成的近源沉积,沉积物来不及分选
岩相D	平行层理砾岩	30~110	平行层理	在快速迁移的、宽而浅的河道环境,或是在冲积扇下游的非河道化泛滥作用
岩相E	交错层理砾岩	15~60	槽状、板状交错层理	板状交错层理主要是在低流态条件下,由大的直脊波纹和沙丘迁移形成的,而槽状交错层理是由小型水流波纹迁移形成的
岩相F	聚集状砾岩	10~20	颗粒支撑的砾石,不显示粒序变化	片流或越岸流体将沉积物表层的细粒组分带走,而剩下粗粒碎屑颗粒聚集形成筛状沉积
岩相G	砂岩	< 40	常与下伏砾岩层渐变构成向上变细的沉积旋回,或呈透镜层状夹于砾岩层之间	以粗砂岩为主,少量为中砂岩,多含有砾石。顶界面为被上覆砾岩下切侵蚀而成的冲刷面