Paleomagnetic results of the Cretaceous marine sediments in Tongyouluke, southwest Tarim

来源 :Science in China(Series D:Earth Sciences) | 被引量 : 0次 | 上传用户:liongliong534
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Paleomagnetic and rock magnetic studies on samples of 18 sites from the Creta- ceous marine sedimentary rocks in the Tongyouluke section, Akto County, southwest Tarim, China show that the magnetic carriers of the Lower Cretaceous are dominated by hematite with some magnetite, while the magnetic carriers of the Upper Cretaceous are characterized by a combination of magnetite and titanomagnetite as well as hematite and goethite. Stepwise thermal demagnetization is performed and vector analysis is used to isolate magnetic components, which illustrates a single magnetic component or double magnetic components. The high temperature stable components are dual polarities and pass polarity test, reversal test and consistency test. The overall mean direction of the Lower Cretaceous is D = 27.0°, I = 42.0°, α95=6.5° with pole position at φ = 190.3°, λ=63.1°, dp=4.9°, dm=8.0°. The overall mean direction of the Upper Cretaceous is D = 29.1°, I = 39.4°, α95=11.2° with pole position at φ =190.9°, λ=60.3°, dp= 8.0°, dm=13.4°. Compared with the inclination of the Early Cretaceous from red beds of north Tarim, the contemporary inclination of southwest Tarim is 10.0°±7.8° sharper, but it is still 8.1° ±8.9°, shallower than that of Early Cretaceous basalts in southwest Tarim. Although these pa- leomagnetic data show slightly larger confidence limit, the paleolatitude of the marine Cretaceous tends to lie between that of terrestrial red beds and volcanic rocks. Paleomagnetic and rock magnetic studies on samples of 18 sites from the Creta-marineous marine sedimentary rocks in the Tongyouluke section, Akto County, southwest Tarim, China show that the magnetic carriers of the Lower Cretaceous are dominated by hematite with some magnetite, while the magnetic carriers of the Upper Cretaceous are characterized by a combination of magnetite and titanomagnetite as well as hematite and goethite. Stepwise thermal demagnetization performed and vector analysis is used to isolate magnetic components, which shows a single magnetic component or double magnetic components. The high temperature The overall mean direction of the Lower Cretaceous is D = 27.0 °, I = 42.0 °, α95 = 6.5 ° with pole position at φ = 190.3 °, λ = 63.1 °, dp = 4.9 °, dm = 8.0 °. The overall mean direction of the Upper Cretaceous is D = 29.1 °, I = 39.4 °, α95 = 11.2 ° with pole p Position at φ = 190.9 °, λ = 60.3 °, dp = 8.0 °, dm = 13.4 °. Compared with the inclination of the Early Cretaceous from red beds of north Tarim, the contemporary inclination of southwest Tarim is 10.0 ° ± 7.8 ° sharper , but it is still 8.1 ° ± 8.9 °, shallower than that of Early Cretaceous basalts in southwest Tarim. Although these paleolatitude of the marine Cretaceous tends to lie between that of terrestrial red beds and volcanic rocks.
其他文献
病人男,22岁.腹胀、气促2个月,全身水肿5d.曾诊断为多浆膜腔积液,肺部感染.心脏彩色超声报告为左房黏液瘤,心包大量积液,转入我科.实验室检查示凝血功能异常、肝肾功能不全.2003年3月在全麻中度低温体外循环下急诊手术,麻醉诱导期间心率下降至40次/min,血压70/50mmHg(9.33/6.67kPa),血氧饱和度0.8.考虑为肿瘤堵塞,紧急开胸建立体外循环.术中见心包内淡黄积液300ml,
患者男,83岁.前列腺癌电切术后4个月,发现左侧阴囊肿块3个月余就诊我院.前列腺特异抗原(PSA)<4 ng/ml,睾酮 0.01 nmol/ml(正常值:9.01~45.75 nmol/ml)。
通过对广东商学院华商学院200名非英语专业学生的问卷调查,分析学生对多媒体技术在当前大学英语自主学习中的应用态度,构建基于多媒体环境的自主学习模式。 Through the que
5月9日上午,由省教育厅、省委宣传部等6部门共同举办的2017年云南省职业教育活动周启动仪式暨云南省高等学校学生职业技能大赛闭幕式在云南机电职业技术学院举行。省政府副省
The Tsagaanbulag Formation of the Ulaan-Shand section in the Shine Jinst area was assigned to Silurian (Wenlock-Pridoli) previously. But the present authors hav
太赫兹分谐波混频器的变频损耗、噪声系数等指标与基波混频器相近,且本振频率为射频频率的一半,大大降低了本振源的设计难度和制作成本,是高性能太赫兹接收前端的关键部件。
法学是一门实践性、应用性很强的学科,法律理论知识只有在司法实践中得以运用,才能体现法律的价值。高职法律教师专业实践性教学严重不足,需要通过提高师资水平,改革教学手段
“午夜惊奇单元”是上海国际电影节开办以来首次设立,该单元的展映包括《低俗小说》《迷墙》《驱魔人》《午夜凶铃》和《死侍》共五部影片,作为“惊奇”元素的集中放映,吸引
2014年9月26日,中国科技信息研究所在京召开了中国科技论文统计结果发布会,发布了《中国科技核心期刊引证报告(核心版)》。据2013年林学类22种核心期刊的主要指标显示,《经济
一个由法国和美国科学家组成的研 究小组日前表示,通过地震监控网监测 海洋水流、大气气流对地面的影响,或 者说由此发出的声响,他们绘制出了加 利福尼亚州地下深层的结构图