Sedimentary Characteristics of Late Quaternary Loess in Hexigten Global Geopark and Its Paleoclimatic Implications

doi:10.19657/j.geoscience.1000-8527.2023.071

Abstract

Abstract:

Loess has various paleoclimatic indicators, among which the particle size and magnetic susceptibility are important objects for paleoclimate research, and detailed studies on loess layers in different regions can faci-litate global climate change comparison and climate cycle division. Taking the Holocene Sanyixiang loess profile and the Upper Pleistocene Tuchengzi loess profile of Hexigten Global Geopark as an example, the loess samples were subjected to ¹⁴C dating, photoluminescence dating, grain size and magnetic susceptibility analyses. The regional paleoenvironmental change since the Late Quaternary was reconstructed, which provided a new and strong evidence for studying the climate types in northern China. The ¹⁴C dating on the Sanyixiang profile yielded 2.32 ka, 9.05 ka, 9.94 ka and 11.27 ka, whilst the OSL dating on the Tuchengzi profile yielded 21.5 ka, 23.5 ka, 43.9 ka, 53.4 ka, which show that the Sanyixiang and Tuchengzi profiles are Late Quaternary. The Sanyixiang and Tuchengzi profiles are young and old, respectively, forming a relatively complete loess sequence. The study shows that coarse silt(16-63 μm) was a major course-size component in the loess-paleosol deposition, accounting for 61.45%-62.4%, followed by sand(>63 μm) and clay(<4 μm). Based on stratigraphic features and grain-size curve, the Hexigten area underwent cold-hot, dry-humid cycles and at least four summer monsoon intensifying events. The grain size and magnetic susceptibility records of the Sanyi-xiang/Tuchengzi loess profiles are basically similar to those of the Luochuan profile of the loess plateau, with coarser grain size and lower magnetic susceptibility during the glacial period. Meanwhile, the magnetic susceptibility of the interglacial or interglacial step increases significantly, and the grain size becomes significantly smaller, indicating that the paleoenvironmental evolution of the two places was controlled by the East Asian monsoon intensity in a glacial-interglacial timescale.

Key words: grain size, magnetic susceptibility, paleoclimate, global geopark, Hexigten

CLC Number:

LIU Xiaohong. Sedimentary Characteristics of Late Quaternary Loess in Hexigten Global Geopark and Its Paleoclimatic Implications[J]. Geoscience, 2023, 37(03): 821-833.

Figures/Tables 15

Fig.1 Location map (a) and geological map (b) of the Hexigten Global Geopark

Fig.2 Holocene loess-paleosoil stratigraphic profile (a) and stratigraphic measurement profile (b) at Sanyixiang

Fig.3 Late Pleistocene stratigraphic profile at Tuchengzi

Fig.4 Late Pleistocene loess-paleosoil stratigraphic measurement profile at Tuchengzi

Table 1 Grain-size distribution in the Sanyixiang profile

地层	量值	砂粒 (>63 μm)	粗粉砂 (32~63 μm)	中粉砂 (16~32 μm)	细粉砂 (4~16 μm)	黏粒 (<4 μm)
整个剖面	均值	26.78 14.66~55.05	18.54 12.81~24.34	16.36 5.07~27.16	27.5 10.62~39.13	10.82 4.88~17.24
整个剖面	范围	26.78 14.66~55.05	18.54 12.81~24.34	16.36 5.07~27.16	27.5 10.62~39.13	10.82 4.88~17.24
黄土	均值	27.5 14.66~55.05	18.3 14.58~24.39	16.7 5.07~27.16	26.13 10.62~39.94	10.36 4.88~17.24
黄土	范围	27.5 14.66~55.05	18.3 14.58~24.39	16.7 5.07~27.16	26.13 10.62~39.94	10.36 4.88~17.24
古土壤	均值	25.6 17.75~36.29	17.55 12.81~21.81	15.75 10.49~24.59	29.6 19.03~39.13	11.5 5.28~17.13
古土壤	范围	25.6 17.75~36.29	17.55 12.81~21.81	15.75 10.49~24.59	29.6 19.03~39.13	11.5 5.28~17.13

Fig.5 Variation curves of median particle size and content of different particle level components with depth in the Sanyixiang profile

Table 2 Grain-size distribution in the Tuchengzi profile

地层	量值	砂粒 (>63 μm)	粗粉砂 (32~63 μm)	中粉砂 (16~32 μm)	细粉砂 (4~16 μm)	黏粒 (<4 μm)
整个剖面	均值	19.80 5.22~40.67	22.56 11.32~32	14.66 8.12~19.15	24.23 12.39~38.72	18.67 8.80~32.10
整个剖面	范围	19.80 5.22~40.67	22.56 11.32~32	14.66 8.12~19.15	24.23 12.39~38.72	18.67 8.80~32.10
黄土	均值	21.52 5.22~40.67	22.73 11.32~32	13.72 8.12~19.15	23.56 12.39~38.72	18.47 8.80~32.10
黄土	范围	21.52 5.22~40.67	22.73 11.32~32	13.72 8.12~19.15	23.56 12.39~38.72	18.47 8.80~32.10
古土壤	均值	14.50 9.21~21.32	22.01 18.9~25.04	17.60 15.93~18.64	26.56 23.24~29.13	17.62 15.80~24.54
古土壤	范围	14.50 9.21~21.32	22.01 18.9~25.04	17.60 15.93~18.64	26.56 23.24~29.13	17.62 15.80~24.54

Fig.6 Variation curves of median particle size and content of different particle level components with depth in the Tuchengzi profile

Fig.7 Stratigraphic and magnetic susceptibility variation in the Sanyixiang(a) and Tuchengzi(b) profiles

Table 3 14C dating results for the Sanyixiang profile

剖面	样品深度(cm)	测年方法	结果(ka)	误差(ka)
三义乡	80	¹⁴C测年	2.32	0.09
三义乡	200	¹⁴C测年	9.05	0.09
三义乡	250	¹⁴C测年	9.94	0.06
三义乡	300	¹⁴C测年	11.27	0.11

Table 4 OSL dating results for the Tuchengzi profile

剖面	样品深度(cm)	测年方法	结果(ka)	误差(ka)
土城子	40	光释光测年	21.5	2.5
土城子	160	光释光测年	23.5	2.4
土城子	260	光释光测年	43.9	4.4
土城子	380	光释光测年	53.4	7.3

Fig.8 Susceptibility fluctuation diagram of the Sanyixiang and Tuchengzi profiles

Fig.9 Particle size change diagram of Sanyixiang and Tuchengzi profiles

Fig.10 Integrated map of multiple climate indicators in the Sanyixiang profile

Fig.11 Comparison of magnetic susceptibility and particle size records of Sanyixiang/Tuchengzi and Luochuan loess profiles, and their correlation with the northern hemisphere ice volume [40] and high-latitude summer solar radiation changes [41]

References 45

[1]	AN Z S, KUKLA G J, PORTER S C, et al. Magnetic susceptibility evidence of monsoon variation on the Loess Plateau of central China during the last 130,000 years[J]. Quaternary Research, 1991, 36(1): 29-36. DOI URL
[2]	SUN Y B, AN Z S, CLEMENS S C, et al. Seven million years of wind and precipitation variability on the Chinese Loess Plateau[J]. Earth and Planetary Science Letters, 2010, 297(3/4): 525-535. DOI URL
[3]	赵庆, 郑祥民, 周立旻, 等. 末次冰期东海嵊山岛黄土粒度端元分析及其环境意义[J/OL]. 沉积学报, 2023, 1-18. [2022-08-11]. https://doi.org/10.14027/j.issn.1000-0550.2022.085.
[4]	杨丽雯. 东北地区中更新世气候演化的黄土记录研究[D]. 金华: 浙江师范大学, 2022.
[5]	苏友桥. 内蒙东部黄土湿陷特征及其机理的探讨[J]. 土工基础, 1993, 7(1): 40-44.
[6]	乌云其木格. 内蒙古地貌的发育与特征[J]. 阴山学刊(社会科学版), 1995(增): 32-36.
[7]	张文山, 刘金峰, 田全伦. 赤峰南山顶部黄土古地磁事件及其区域地质表现[J]. 河北地质学院学报, 1994, 17(3): 236-244.
[8]	温泉波, 邓金宪, 刘玉英, 等. 内蒙古大青山北麓黄土堆积的年代、粒度特征及古气候意义[J]. 世界地质, 2003, 22(4): 385-391.
[9]	宋基灵. 浑善达克沙地边缘黄土记录的环境演变及物源探讨[D]. 北京: 中国地质大学(北京), 2017.
[10]	SONG J L, SUN H Y, TIAN M Z, et al. Heinrich events recorded in a loess-paleosol sequence from Hexigten, Inner Mongolia[J]. Geoscience Frontiers, 2018, 9(2): 431-439. DOI URL
[11]	弋双文, 鹿化煜, 周亚利, 等. 晚第四纪科尔沁沙地干湿变化的黄土记录[J]. 中国沙漠, 2006, 26(6): 869-874.
[12]	郭佳宁. 内蒙古宁城中更新世以来黄土磁化率与粒度特征及古环境研究[D]. 北京: 中国地质大学(北京), 2009.
[13]	吕安琪, 鹿化煜, 曾琳, 等. 1.08 Ma以来中国东北赤峰地区黄土粒度变化及其揭示的沙地扩张事件[J]. 中国沙漠, 2017, 37(4): 659-665. DOI
[14]	孙洪艳, 田明中, 武法东. 克什克腾世界地质公园青山花岗岩臼的特征及成因研究[J]. 地质论评, 2007, 53(4): 486-490, 579.
[15]	张振. 克什克腾世界地质公园地热水水文地球化学特征及成因初步分析[D]. 北京: 中国地质大学(北京), 2019.
[16]	逯宏菲. 大连市马栏河阶地黄土剖面粒度特征及地球化学特征分析[D]. 大连: 辽宁师范大学, 2020.
[17]	张婷, 祝一志, 杨亚长, 等. 陕西蓝田全新世黄土AMS-¹⁴C测年与环境变迁[J]. 中国沙漠, 2011, 31(3): 678-682.
[18]	王恒松, 黄春长, 周亚利, 等. 渭河中游全新世黄土剖面光释光测年及记录的古洪水事件[J]. 地质学报, 2012, 86(6): 994-1004.
[19]	ZHAO C L, SHAO M A, JIA X X, et al. Particle size distribution of soils(0-500 cm) in the Loess Plateau, China[J]. Geoderma Regional, 2016, 7(3): 251-258. DOI URL
[20]	吕枫, 胡海平, 叶长盛, 等. 林芝地区风尘堆积及其古环境意义[J]. 干旱区资源与环境, 2022, 36(12): 89-94.
[21]	HELLER F, LIU T S. Paleoclimatic and sedimentary history from magnetic suscepbility of loess in China[J]. Geophysical Research Letter, 1986, 29: 142-152.
[22]	刘东生, 孙继敏, 吴文祥. 中国黄土研究的历史、现状和未来: 一次事实与故事相结合的讨论[J]. 第四纪研究, 2001, 21(3): 185-207.
[23]	杨宇哲, 岳大鹏, 赵景波, 等. 陕西横山地区L3黄土与S3古土壤元素地球化学特征与环境变化[J]. 地理科学进展, 2023, 42(2): 364-379. DOI
[24]	梁潇, 杨萍果, 姚娇, 等. 16 ka以来黄土高原东亚夏季风变化的环境磁学记录[J]. 地理学报, 2021, 76(3): 539-549. DOI
[25]	田庆春, 石小静, 郝晓龙. 临汾盆地黄土沉积记录的末次冰期千年尺度气候事件[J]. 干旱区研究, 2022, 39(4): 1027-1035.
[26]	吕一凡, 张春霞, 付扬, 等. 最近880 ka以来黄土-古土壤序列黏土矿物和黏粒地球化学特征及东亚夏季风演化[J]. 第四纪研究, 2022, 42(4): 921-938.
[27]	陈渠, 吕镔, 刘秀铭, 等. 伊犁典型黄土磁学与常量元素地球化学特征及其古气候意义[J]. 第四纪研究, 2021, 41(6): 1632-1644.
[28]	岳乐平. 中国黄土区东亚古季风气候与冰期气候对比研究[J]. 西北大学学报(自然科学版), 1998, 28(2): 157-162.
[29]	刘小丰, 潘保田, 高红山, 等. 天水黄土沉积特征与环境变化[J]. 中国沙漠, 2007, 27(3): 373-378.
[30]	王琳栋, 杨太保, 梁烨, 等. 会宁地区全新世黄土沉积粒度特征及其古气候意义[J]. 干旱区研究, 2016, 33(6): 1150-1156.
[31]	施雅风, 孔昭宸, 王苏民, 等. 中国全新世大暖期鼎盛阶段的气候与环境[J]. 中国科学(B辑化学生命科学地学), 1993, 23(8): 865-873.
[32]	施雅风, 孔昭宸, 王苏民, 等. 中国全新世大暖期的气候波动与重要事件[J]. 中国科学(B辑化学生命科学地学), 1992, 22(12): 1300-1308.
[33]	吴立, 李晨晨, 马春梅, 等. 巢湖碳氮地球化学沉积记录揭示的全新世以来环境演化[J/OL]. 生态学报, 2023, 43(16): 1-15. [2023-03-22]. https://kns.cnki.net/kcms/detail/11.2031.Q.20230320.1754.002.html.
[34]	肖春凤, 孙启顺, 陈亮, 等. 南海西北部16 ka B.P.以来沉积物的环境磁学特征及其物源指示意义[J]. 海洋地质与第四纪地质, 2023, 43(1): 13-26.
[35]	王丽艳, 李广雪. 古气候替代性指标的研究现状及应用[J]. 海洋地质与第四纪地质, 2016, 36(4): 153-161.
[36]	欧阳婷萍, 田成静, 朱照宇, 等. 南海南部YSJD-86GC孔沉积物磁性特征及其环境意义[J]. 科学通报, 2014, 59(19): 1881-1891.
[37]	李明启, 靳鹤龄, 张洪, 等. 浑善达克沙地磁化率和有机质揭示的全新世气候变化[J]. 沉积学报, 2005, 23(4): 683-689.
[38]	赵景波, 郝玉芬, 岳应利. 陕西洛川地区全新世中期土壤与气候变化[J]. 第四纪研究, 2006, 26(6): 969-975.
[39]	董光荣, 金炯, 高尚玉, 等. 晚更新世以来我国北方沙漠地区的气候变化[J]. 第四纪研究, 1990, 10(3): 213-222.
[40]	MARTINSON D G, PISIAS N G, HAYS J D, et al. Age dating and the orbital theory of the ice ages: Development of a high-resolution 0 to 300,000-year chronostratigraphy[J]. Quaternary Research, 1987, 27(1): 1-29. DOI URL
[41]	BERGER A, LOUTRE M F. Insolation values for the climate of the last 10 million years[J]. Quaternary Science Reviews, 1991, 10(4): 297-317. DOI URL
[42]	PORTER S C, KUKLA G. The long-term paleomonsoon variation recorded by the loess-paleosol sequence in Central China[J]. Quaternary International, 1990, 7/8: 91-95. DOI URL
[43]	安芷生, 刘晓东. 东亚季风气候的历史与变率[J]. 科学通报, 2000, 45(3): 238-249.
[44]	鹿化煜, 周亚利, MASON J, 等. 中国北方晚第四纪气候变化的沙漠与黄土记录: 以光释光年代为基础的直接对比[J]. 第四纪研究, 2006, 26(6): 888-894.
[45]	易施钰, 盛美, 李宗耀, 等. 11万年来河西走廊东部黄土沉积记录的百年分辨率东亚冬季风变化[J]. 第四纪研究, 2022, 42(6): 1517-1528.