萨拉乌苏河流域MGS2层段粒度与CaCO3记录的千年尺度气候变化
作者简介:王丰年(1974-),男,江西信丰人,博士研究生,研究方向为环境及其演变。E-mail:wangfengnian2004@163.com
收稿日期: 2011-09-30
要求修回日期: 2011-12-12
网络出版日期: 2012-05-20
基金资助
国家自然科学基金(编号49971009,40772118)、国家重点基础研究发展计划(973计划)(编号2010CB833405)资助
Millennium-scale Climate Variations from the Record of Grain-size and CaCO3 During the Pleniglacial in the Salawusu River Valley, China
Received date: 2011-09-30
Request revised date: 2011-12-12
Online published: 2012-05-20
Copyright
测定、分析毛乌素沙漠东南缘萨拉乌苏河流域米浪沟湾剖面MGS2层段的粒度与CaCO3,发现该层段不同沉积相粒度Mz和σ呈现峰谷变化,CaCO3含量在沙丘砂及其上覆的河流相和湖沼相中依次变化于0~2.94%(平均值0.39%)、0.14%~2.68%(1.43%)和0.39%~15.57%(8.82%),并与Mz呈显著相关,构成与沉积旋回波动韵律相同的5.5个峰谷交替的粒度与CaCO3旋回。研究表明,毛乌素沙漠冬季风盛行时期沙丘砂强烈堆积,CaCO3发生迁移;夏季风盛行时期河流相和湖沼相发育,粉砂和粘土含量增加,CaCO3相对聚集。这些旋回代表东亚冬夏季风千年尺度交替变化的气候旋回。
王丰年 , 李保生 , 王江龙 , 牛东风 , 温小浩 , 李志文 , 司月君 , 杜恕环 . 萨拉乌苏河流域MGS2层段粒度与CaCO3记录的千年尺度气候变化[J]. 地理科学, 2012 , 32(5) : 596 -602 . DOI: 10.13249/j.cnki.sgs.2012.05.596
The MGS2 segment of the Milangguowan stratigraphical section in the Salawusu River Valley, southeast of China’s Mu Us Desert, records 5.5 sedimentary cycles consisting of dune sands alternating with fluvial or lacustrine facieses. Based on the grain-size and CaCO3 analysis, it was found that Mz and σ appear peaks and valleys in different sedimentary facieses. CaCO3 contents range from 0 to 2.94% (average 0.39%) in the dune sands, 0.14% to 2.68% (average 1.43%) in the fluvial facieses and 0.39% to 15.57% (average 8.82%) in the lacustrine, and appear 5.5 grain-size and CaCO3 cycles similar to the sedimentary facieses changes. And the CaCO3 contents have a significant correlation with Mz. The result show that the dune sands accumulate and CaCO3 moved greatly during the periods with a strong cold-dry winter monsoon. Whereas, the fluvial or lacustrine facieses developed, silt and clay increased and CaCO3 gathered largely when the warm-humid summer monsoon strengthened. The observed climate fluctuations on millennium-scale during the Pleniglacial to the alternations attributed the strength of the East Asian winter and summer monsoons.
Fig.1 The location of Salawusu River and the study area图1 米浪沟湾地层剖面位置及其所在萨拉乌苏河流域概况 |
Table 1 TL dating results of some horizons and their parameters in the MGS2表1 MGS2及相关层位的热释光年代测定值和测试参数 |
层位/样品编号 | 深度 (m) | U (10-6) | Th (10-6) | K(10-6) | 年剂量(m Gy) | 总剂量 (Gy) | TL (ka B.P.) |
---|---|---|---|---|---|---|---|
18D/TGD-627 | 8.44 | 0.92±0.05 | 6.07±0.12 | 1.91±0.015 | 2.48±0.08 | 186.20±13.96 | 9.88±0.9 |
24D/PKG586 | 10.525 | 1.834 | 8.514 | 1.140 | 2.652 | 33.562±4.774 | 14.458±0.867 |
26D/XAL895 | 11.645 | 5.5 | 4.1 | 1.70 | 3.16 | 60.806±3.21 | 19.236±1.554 |
Table 2 The ages (ka BP)of each layer in the MGS2表2 MGS2各层位年代 |
层位 | 深度(m) | 起止年龄 (ka B.P.) | 层位 | 深度(m) | 起止年龄 (ka B.P.) |
---|---|---|---|---|---|
20D | 8.99~8.76 | 11.09~10.58 | 21FL | 9.39~8.99 | 11.97~11.09 |
22D | 9.74~9.39 | 12.63~11.97 | 23FL | 10.27~9.74 | 13.90~12.63 |
24D | 10.78~10.27 | 16.47~13.90 | 25LS | 11.41~10.78 | 19.11~16.47 |
26D | 11.88~11.41 | 19.67~19.11 | 27LS | 12.10~11.88 | 20.07~19.67 |
28D | 12.50~12.10 | 20.81~20.07 | 29FL | 12.74~12.50 | 21.25~20.81 |
30D | 13.63~12.74 | 22.89~21.25 |
Fig.2 The sedimentary sequences and ages in the MGS2 of the Milanggouwan section图2 米浪沟湾剖面MGS2沉积序列与时间标尺 |
Fig. 3 CaCO3 contents and the variations in the MGS2图3 MGS2层段CaCO3含量及其变化 |
Fig. 4 The scatter of Mz(Φ)-CaCO3(%) in different sedimentary facieses of the MGS2图4 MGS2不同沉积相Mz(Φ)-CaCO3(%) |
The authors have declared that no competing interests exist.
[1] |
|
[2] |
|
[3] |
|
[4] |
|
[5] |
|
[6] |
|
[7] |
|
[8] |
|
[9] |
|
[10] |
|
[11] |
|
[12] |
|
[13] |
|
[14] |
|
[15] |
|
[16] |
|
[17] |
|
[18] |
|
[19] |
|
[20] |
|
[21] |
|
[22] |
|
[23] |
|
[24] |
|
[25] |
|
[26] |
|
[27] |
|
[28] |
|
[29] |
|
[30] |
|
[31] |
|
[32] |
|
[33] |
|
/
〈 | 〉 |