白垩系古沙漠露头遥感特征及其识别方法——以湘东南地区红层盆地为例
Remote Sensing Characteristics and Identification Methods of Cretaceous Palaeo-desert Outcrop:Taking the Red Bed Basin in Southeast Hunan as an Ex-ample
周丽芸 1黄乐清2
作者信息
- 1. 湖南省地质调查所,湖南长沙 410116
- 2. 湖南省地质调查所,湖南长沙 410116;中国地质大学地质调查研究院,湖北武汉 430074;古生物与地质环境演化湖北省重点实验室,湖北武汉 430205
- 折叠
摘要
白垩系古沙漠风成砂岩是近年来湖南省新发现的一种沉积类型,该岩石不仅是特色的旅游资源,而且是全球关注的储能、储碳的重要目标储集层,因此对湖南省古沙漠的空间分布规律深入研究意义重大.本文引入遥感技术手段建立古沙漠露头遥感特征的识别及提取方法:以谷歌地球引擎(Google Earth Engine,GEE)为主要处理平台,以Sentinel-2A(哨兵二号)多光谱影像为主要数据源,从光谱、遥感指数和地形地貌三个方面分析古沙漠露头的遥感特征,采用随机森林算法进行古沙漠露头的遥感识别.区别于传统的陡直型丹霞地貌,古沙漠遥感影像色调均匀、连片分布,植被和山体阴影皆不发育,具有"顶圆,坡缓"的地貌特征.同时,深入分析古沙漠地貌的岩性特征,结合地质条件辅助约束,实现古沙漠露头的精准识别.通过上述方法,本文解译出湖南白垩系丹霞地貌区的多处古沙漠露头,并从识别结果中选择面积较大的衡阳盆地东缘(渡口地区)和茶永盆地东南缘(郴州市飞天山-高椅岭地区)地区的古沙漠风成砂岩进行了实地验证,效果理想.本文为研究古沙漠空间分布规律提供了高效的途径,是遥感技术在古沙漠地质领域的重要应用,旨在为国内地学界同行提供技术参考和借鉴.
Abstract
The Cretaceous palaeo-desert aeolian sandstone is a new type of sedimentary discovered in Hunan Province in recent years.This rock is not only a characteristic tourism resource,but also an important target reservoir for energy and carbon storage of global concern,so it is of great significance to conduct an in-depth study on the spatial distribution pattern of palaeo-deserts in Hunan Province.In this paper,remote sensing technology is introduced to establish the recognition and extraction method of remote sensing features of pal-aeo-desert outcrops:With Google Earth Engine(GEE)as the main processing platform and Sentinel-2A multi-spectral image as the main data source,by analyzing the remote sensing characteristics of palaeo-desert outcrops from three aspects:spectral,remote sensing index and topography and geomorphology features,and the Random Forest Algorithm was used to identify the palaeo-desert outcrops by remote sensing.Different from the traditional steep and straight Danxia landforms,the remote sensing images of the palaeo-desert are uniform in colour tone,continuously distributed,with undeveloped vegetation and mountain shadows,and with the geomorphological characteristics of'rounded tops and gentle slopes'.At the same time,deeply ana-lysing the stratigraphic lithology characteristics of the palaeo-desert,the outcrop of the palaeo-desert is char-acterized accurately by increasing geological constraints.With the methods above,a number of palaeo-desert outcrops in Danxia landform area of various red bed basins in Hunan Province have been interpreted,and two large areas of palaeo-desert aeolian sandstones in the eastern margin of Hengyang Basin(Dukou area)and the southeastern margin of Chayong Basin(Feitianshan-Gaoyiling area of Chenzhou City)have been verified.This study provides an efficient way to study the spatial distribution law of palaeo-desert,which is an impor-tant application of remote sensing technology in the field of geology,aiming to provide technical and geosci-ence references.
关键词
古沙漠/遥感特征/Sentinel-2A/谷歌地球引擎/随机森林算法/湖南省Key words
palaeo-desert/remote sensing feature/Sentinel-2A/Google Earth Engine/Random Forest Algo-rithm/Hunan province引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据