论文部分内容阅读
Methane (CH4) and dioxide (CO2) are atmospheric greenhouse gases (GHG) generated from both natural and anthropogenic processes.GHG emission from geological sources such as volcanic activity,seabed gas hydrate release,hydrocarbon seepage as well as uncontrolled combustion of fossil fuels is erratic and difficult to quantify.A baseline inventory of global geologic,land surface greenhouse gas sources/sinks is not yet available through emerging Earth Observation (EO) technologies can potentially fill this gap and provide ongoing monitoring.In this presentation we present the earth observation (remote sensing) technologies which can detect the GHG emission due to seepages from petroleum reservoirs and spontaneous coal seam fires deposits (coal fires).Oil and gas seeps,varying quantities of oil and gas migrate to the surface as macroseeps,which are visible,and microseeps,which are invisible.This stduy describes the mechanisms of seepage and the resulting surface manifestations related to optical high-resolution remote sensing data.Microseeps are more difficult to study using remote sensing,but they may produce geochemical alterations in surface soil and rocks,which can be studied indirectly using multispectral to hyperspectral remote sensing data.An integrated methodology is presented to combine various geoscience and remote sensing datasets for seepage detection in the Tian Shan.Multispectral remote sensing tools are not only important for petroleum exploration,but also have environmental implications because seeps emit greenhouse gases.Coal fires,both underground and on the surface,are a serious problem in most major coal-producing countries of the world,such as China and central Asia.Combustion can occur spontaneously or due to anthropogenic causes,either within underground coal seams or in exposed layers of coal on Earths surface.Coal fires are difficult to extinguish and sometimes cannot be controlled.In addition to burning millions of tons of coal,the fires have an enormous negative impact on the local and global environments.Coal fires produce large quantities of greenhouse gases,such as CO,CO2,SO2,and CH4,which have a direct impact on the local and global atmospheric composition.The scientific study of coal fires thus becomes essential to track them in remote locations.This presentation will discuss the significance of earth observation as a reliable tool to detect and monitor coal fires in the Tian Shan,with a review of coal fires and related environmental issues.