Remote Sensing Interpretation And Application Of Sedimentary Lithology

Remote sensing is an important investigation geological method,which has a wide range of applications in the geological survey,including structure,fracture,disaster,magmatic rock and metamorphic rock.Especially in the large-scale geological survey,and it has greatly improved the efficiency of the field work and surveying accuracy.However,there are always some problems in the interpretation of sedimentary rocks.The minerals that make up the sedimentary rocks are complex and changeable,and their structure and structural similarities are high,which has led to the incomplete interpretation of sedimentary rocks.Dalongkou area is located in the joints of the basins(southeast of the Junggar Basin and the northwestern margin of the Tianshan structural belt)structural belt.The sedimentary rocks in the Dalongkou area are extensively developed,with well exposed strata,less vegetation coverage,clear strata boundaries,and clear time divisions.It is one of the typical geological profiles of Permian and Triassic;In this area,the predecessors carried out a large number of geological exploration work,the research results are very detailed,and the regional research maturity is high;the World View-2 remote sensing image data of the study area has high resolution and rich geological information,suitable for use as a base map when interpreting.This article selected Dalongkou as the research area and was inancially supported by the project " Permian-Triassic petroleum geological profile construction in Dalongkou" to try carry out the research on the remote sensing interpretation of sedimentary rocks.The application of remote sensing lithology interpretation in sedimentary rock area is based on the theory of rock spectrum.It uses the processing of different remote sensing images to enhance the characteristics of lithologic spectral information and extract the target lithologic information.In this paper,through the actual survey work of the section in the study area,rocks of different layers of lithology are sampled,and the spectrum of the collected samples is tested.The obtained rock sample spectra are resampled and smoothed using View Specpro professional software.Different preprocessing of Landsat-8 and World View-2 images was done using ENVI software.Combine the common features of the two types of spectral data to analyze the characteristics of different lithological spectral curves.And combined with USGS's typical mineral spectral library,comprehensive information was used for comparison and discrimination,and a typical lithology spectral library in the study area was established.Spectral angle matching was performed between the spectra in the image and the typical lithology spectral library in the study area,and accuracy evaluation of the matching lithologic classification results.At the same time,the method of supervised classification is used to identify the lithology of Landsat-8 images,and the advantages and disadvantages of the two methods are compared.Finally,the lithologic-stratigraphic boundary map of the Da Longkou area is obtained based on the information following four aspects: the field survey section,the previous research results,the indoor slice identification,and the interpretation of lithology classification map.According to the characteristics of different image data,this paper uses different preprocessing methods to develop a set of preprocessing flow for Landsat-8 and World View-2images.According to the indoor measured rock spectrum data,dividing 9 lithologies in the study area,a typical spectral library of sedimentary rocks in the study area was established,which can be used for reference in the interpretation of other areas.According to the different classification methods,the supervised classification method is applied to Landsat-8 images,and the method of spectral angle matching is applied to World View-2 images.It is concluded that the integrated application of the two methods can accurately divide the boundary of lithology.The analysis and evaluation of the interpretation results of the study area,and verification in similar areas shows that the research method has certain practical value.Based on the comprehensive analysis of field measured profiles and remote sensing lithologic interpretation maps,the lithologic-stratigraphic interpretation maps are obtained,which shows the necessity of comprehensive information for research.