| 摘要: |
| 贵州赤水地区位于四川盆地西南缘，晚白垩世时期该地区沉积了一套厚达1300m的陆相地层。本文通过地表露头的古流向野外观测和室内分析，详细研究赤水地区晚白垩世沉积充填过程及构造意义。赤水地区晚白垩世早期辫状河的古流向为自北东向南西，表明碎屑物源主要来自盆地北侧和东侧。根据物源、地层分布及区域地质背景推断，赤水地区晚白垩世的陆相沉积盆地属于陆内前陆盆地，陆内造山带位于盆地东侧。晚白垩世陆内前陆盆地的形成，可能受控于此阶段华南的构造挤压事件形成的陆内造山作用。 |
| 关键词: 贵州赤水 晚白垩世 构造意义 四川盆地 古流向 |
| DOI： |
| 附件 |
| 投稿时间：2019-03-01修订日期：2019-04-12 |
| 基金项目:本研究受赤水丹霞国家地质公园管理局科研项目《赤水丹霞白垩纪沉积环境及演化序列研究》和国家自然科学基金项目（41703037）共同资助 |
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| The Late Cretaceous palaeocurrents in the Chishui region, Guizhou and their tectonic significance |
| CAO Rui1, YAN Zhaokun2, WANG Zhiyong3, QIANG Kun1, CHEN Xiufeng3 |
(1. College of Earth Sciences, Chengdu University of Technology, Chengdu 610059, Sichuan, China;
2. State Key Laboratory of Nuclear Resources and Environments, East China University of Technology, Nanchang 330013, Jiangxi, China;
3. Danxia National Geopark Administration, Chishui 564700, Guizhou, China) |
| Abstract: |
| A succession of 1300-m thick continental strata was deposited during the Late Cretaceous in the Chishui region, Guizhou on the southwestern margin of the Sichuan Basin. In this paper, the Late Cretaceous sediments filling processes and tectonic significance are explored on the basis of field observation and indoor analysis of the palaeocurrents indicated by the surface outcrops in the Chishui region. The palaeocurrents in the braided streams were directed from northeast to southwest during the Late Cretaceous, indicating that the sediments detritus in the Chishui region may come mainly from the northern and eastern parts of the Basin. Judged from the provenance, stratigraphic distribution and regional geological background, it is inferred that the Late Cretaceous continental sedimentary basin in the Chishui region may belong to the intracontinental foreland basin, and the intracontinental orogenic zones appear in the eastern part of the Basin as a major provenance. The formation of the Late Cretaceous intracontinental foreland basin in the Chishui region may be governed by the intracontinental orogeny caused by the tectonic compression events in South China during the Late Cretaceous, and thus the Sichuan Basin has gone through the evolution from a fresh lake to a saline lake. |
| Key words: Chishui in Guizhou Late Cretaceous tectonic significance Sichuan Basin palaeocurrents |
