干旱区生态环境知识资源中心(Arid): 四川盆地上三叠统须家河组沉积时期古气候

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	四川盆地上三叠统须家河组沉积时期古气候
其他题名	Paleoclimate during depositional period of the Upper Triassic Xujiahe Formation in Sichuan Basin
	徐兆辉 1; 汪泽成 1; 胡素云 1; 朱世发 2; 江青春 1
来源期刊	古地理学报
ISSN	1671-1505
出版年	2010
卷号	12 期号:4 页码:415-424
中文摘要	四川盆地上三叠统须家河组可分为6段,整体表现为砂一泥间互的沉积结构,古气候是控制这种沉积结构的重要因素之一.文中利用孢粉分析法、黏土矿物分析法和特征元素分析法对全盆地6个采样点、6个层段的泥岩样品进行了系统分析,分别恢复了四川盆地晚三叠世须家河组各段地层沉积时期的古气候.研究表明,四川盆地晚三叠世须家河组沉积时期古气候特征为热带一亚热带背景下发生的温热交替、干湿更迭:须1段为海陆过渡相沉积,该时期温度高、湿度大,为炎热潮湿气候;须2段沉积时期,温度与须1段沉积时期持平或略低、湿度大幅降低,为温和和干燥气候;须3段沉积时期,温度和湿度均比须2段沉积时期高,炎热潮湿,沼泽沉积发育;须4段别积时期,温度升高、湿度略有降低,气候温和干旱;须5段沉积时期,温度和湿度均达到峰值,为整个须家河组沉积时期最炎热潮湿的阶段;须6段沉积时期,温度降至最低、湿度有所下降,气候温和干旱.
英文摘要	The Upper Triassic Xujiahe Formation in the Sichuan Basin can be divided into six members with a texture of interbeded sandstones and mudstones. Paleoclimate is one of the factors controlling the texture. Three methods named palynoflora, clay minerals, and eigen elements analyses were used to reconstruct the paleoclimate during the depositional period of the xujiahe Formation. Mudstone samples of the six members were taken from six different areas through the entire basin, and then were analyzed to reconstruct the paleoclimate, respectively. The palynoflora indicated that the paleoclimate setting during the depositional period of the Xujiahe Formation was hot and humid within tropics-subtropics zone. With clay minerals analysis, the ratio of Kaolinite to Illite(K/I)was used to analyze the paleoclimate, which reduced the ambiguity. Using the ratio of calcium to magnesium(Ca/Mg)and strontium/barium (Sr/ Ba), the details of paleotemperature and paleomoisture (paleosalinity)were reconstructed.It indicates that the paleotemperature and paleomoisture during the depositional period of the Xujiahe Formation fluctuated regularly against the setting of tropics-subtropics. The Member 1 of the Xujiahe Formation was formed in a transitional facies when the paleoclimate was hot and humid. The Member 2 of the Xujiahe Formation was formed in a hot and arid climate. When the Member 3 of the Xujiahe Formation was formed, the temperature and moisture were all higher than the Member 2.It belonged to the swamp environment. After a short decrease of temperature and moisture in the Member 4, it became the hottest and wettest during the period when the Member 5 was formed. The temperature and moisture declined slightly when the Member 6 was formed, and the paleoclimate became warmer and more arid.
中文关键词	四川盆地 ; 晚三叠世 ; 须家河组 ; 古气候 ; 孢粉植物群 ; 黏土矿物 ; 特征元素
英文关键词	Sichuan Basin Late Triassic Xujiahe Formation paleoclimate palynoflora clay minerals eigen elements
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY
WOS研究方向	Geology
CSCD记录号	CSCD:3922260
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/225234
作者单位	1.中国石油勘探开发研究院, 北京 100083, 中国; 2.中国石油大学(北京)地球科学学院, 北京 102249, 中国
推荐引用方式 GB/T 7714	徐兆辉,汪泽成,胡素云,等. 四川盆地上三叠统须家河组沉积时期古气候[J],2010,12(4):415-424.
APA	徐兆辉,汪泽成,胡素云,朱世发,&江青春.(2010).四川盆地上三叠统须家河组沉积时期古气候.古地理学报,12(4),415-424.
MLA	徐兆辉,et al."四川盆地上三叠统须家河组沉积时期古气候".古地理学报 12.4(2010):415-424.