干旱区生态环境知识资源中心(Arid): 基于ALOS PALSAR影像的莫勒切河洪积扇地貌面定量分期

Arid

	基于ALOS PALSAR影像的莫勒切河洪积扇地貌面定量分期
其他题名	QUANTITATIVE MAPPING OF THE MOLEQIE RIVER ALLUVIAL FAN MORPHOLOGIC UNITS IN CHINA BASED ON ALOS PALSAR DATA
	苏强; 任俊杰; 梁欧博; 郭菲
来源期刊	地震地质
ISSN	0253-4967
出版年	2020
卷号	42 期号:1 页码:79-94
中文摘要	洪积扇是干旱-半干旱地区最普遍、最基本的地貌,洪积扇地貌面记录了第四纪以来构造活动、气候变化的重要信息,为构造运动、古环境和地貌演化等方面的研究提供参考,但目前缺少可靠的区域洪积扇地貌面定量分期方法。洪积扇地貌面的粗糙度是地貌演化过程中一个重要的特征。本研究利用合成孔径雷达(SAR)技术 ,选择公开的空间分辨率为15m的L波段ALOS PALSAR数据,采用横剖面线法获得不同级洪积扇地貌面的后向散射系数,实现阿尔金断裂带西段莫勒切河洪积扇地貌面的大范围定量分期。结果表明: 1)L波段HH极化方式的SAR数据对洪积扇地貌面的粗糙度特征敏感,适合划分莫勒切河地区不同级的洪积扇地貌面;2)在相对平坦的干旱-半干旱地区,S AR数据的后向散射系数主要表征地表的粗糙度,利用后向散射系数可对洪积扇地貌面进行大范围定量分期;3)SAR数据的后向散射系数为划分不同级的洪积扇地貌面提供了一种定量参考指标,可减少因洪积扇地貌面的空间分布不连续导致的地貌面分期误差。
英文摘要	Alluvial fans are the most common landforms in arid and semi-arid regions,which record important information on tectonic and climatic changes,and provide a reference to the Quaternary tectonic activity,paleogeographical environment,and geomorphic evolution.However,there is a lack of reliable quantitative methods for the classification of regional alluvial fan topography.Surface roughness is a terrain parameter that has been supposed to be an inherent property of alluvial fan topography.The smooth of the alluvial fan surface is a gradual,continuous and internal geomorphological process from bar-swale high relief of younger and rough surface to small relief of older and smooth surface over time.Alluvial fan surface roughness declines with the age of abandoned alluvial fan units,indicating that the surface roughness could be used as a parameter to determine the sequence of alluvial fan units.In semi-arid and arid conditions,the subdivision sequence of alluvial fan units is regularly distinguished according to specific qualitative and quantitative techniques.The traditional field mapping provides relatively high levels of accuracy,but it is labor-intensive,time-consuming and applicable for small-scale areas.Aerial or spaceborne optical image quantitative mapping will be limited to the light,weather and the resolution of the image.The infrared and thermal infrared image quantitative mapping is susceptible to the parent material lithology of alluvial materials.Quantitative mapping requires more accuracy and high-resolution data for digital terrain data,which will be timeconsuming and expensive when applied to large and remote locations.In-situ cosmogenic radionuclide method should consider the time and expensive sample testing cost of applying alluvial fan unit mapping.Meanwhile,the uncertainty of the analysis,as well as samples collecting issues and the lack of appropriate dating materials can also limit the application of dating methods to the semi-arid and arid areas.Synthetic Aperture Radar(SAR),an initiative microwave remote sensing technology,can record multi-polarization,multi-band,high-resolution microwave backscattering returns and is sensitive to geomorphic features.The hyper-penetration of clouds makes SAR data an effective way to obtain alluvial fan surface information.Microwave backscatter on the alluvial fan surface contains valuable information about surface roughness.However,surface roughness is difficult to measure using conventional topographic survey instruments.The backscatter coefficient in SAR data is an indirect indicator of surface roughness and plays a key role in rapidly mapping large-scale alluvial fan unit in arid and semi-arid environments.In this study,we use open Advanced Land Observing Satellite(ALOS)Phased Array L-band SAR(PALSAR)data with a resolution of 15m/pixel to extract backscatter coefficients from different geomorphic surfaces by transverse profiles and determine the characteristic roughness values of alluvia fan units.We then apply these characteristic values to different alluvial fan units of the Moleqie River Alluvial Fan(MRAF)and quantitatively map the western section of the Altyn Tagh Fault area.Our results indicate that: 1)L-band HH polarization SAR data is more sensitive to the geomorphic roughness characteristics of the MRAF surface,compared to other polarized SAR data,this data is more suitable for distinguishing alluvial fan units in different periods;2)The backscatter coefficients of SAR data can describe the surface roughness of relatively flat,arid and semi-arid areas and can be used to quantitatively map large-scale alluvial fan units;3)The backscatter coefficients of SAR data provide a quantitative proxy for the classification of alluvial fan units in different periods,reducing alluvial fan mapping mistakes caused by spatial discontinuity of alluvial fan units.This study is beneficial to the quantitative mapping and comparative study of the regional alluvial fan.
中文关键词	莫勒切河 ; 洪积扇地貌面 ; 后向散射系数 ; 定量分期
英文关键词	ALOS PALSAR ALOS PALSAR Moleqie River alluvial fan surfaces backscatter coefficients quantitative mapping
类型	Article
语种	中文
收录类别	CSCD
WOS类目	Geology
CSCD记录号	CSCD:6699653
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/353406
作者单位	苏强, 中国地震局地壳应力研究所, 中国地震局地壳动力学重点实验室, 北京 100085, 中国.; 任俊杰, 中国地震局地壳应力研究所, 中国地震局地壳动力学重点实验室, 北京 100085, 中国.; 梁欧博, 中国地震局地壳应力研究所, 中国地震局地壳动力学重点实验室, 北京 100085, 中国.; 郭菲, 中国地震局地壳应力研究所, 中国地震局地壳动力学重点实验室, 北京 100085, 中国.
推荐引用方式 GB/T 7714	苏强,任俊杰,梁欧博,等. 基于ALOS PALSAR影像的莫勒切河洪积扇地貌面定量分期[J],2020,42(1):79-94.
APA	苏强,任俊杰,梁欧博,&郭菲.(2020).基于ALOS PALSAR影像的莫勒切河洪积扇地貌面定量分期.地震地质,42(1),79-94.
MLA	苏强,et al."基于ALOS PALSAR影像的莫勒切河洪积扇地貌面定量分期".地震地质 42.1(2020):79-94.