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	基于偏度的地震热红外异常提取
其他题名	SEISMIC THERMAL INFRARED ANOMALY EXTRACTION BASED ON SKEWNESS
	刘文宝; 孟庆岩; 张继超; 张颖; 卢显; 孟亚飞
来源期刊	地震地质
ISSN	0253-4967
出版年	2020
卷号	42 期号:6 页码:1509-1524
中文摘要	地震热异常的存在已被大量震例研究所证实,但天气仍是热异常精细提取的限制因素。为此,文中在提取热异常时先采用时间域差值,后计算空间域差值以去除天气因素的影响;引入偏度异常数据监测算法,针对不同样本数选择不同阈值判断热异常。基于以上新算法分析了2016年12月8日呼图壁M_S6.2、2017 年8月8日九寨沟M_S7.0和2017年8月9日精河M_S6.6地震的热异常时空分布情况。结果表明: 1)先采用时间域差值、后计算空间域差值将减少云对温度空间分布差异造成的热异常假象;2)在样本数满足异常判断需求的前提下,当背景场数量发生变化时, 不同样本数对应不同阈值的热异常面积基本不变,热异常判断阈值的稳定性更强;3)九寨沟M_S7.0地震的震前热异常整体围绕震中从NW军功断裂向NE陇县-宝鸡断裂以顺时针移动;呼图壁M_S6.2地震的震前热异常从南往北整体向震中移动;精河M_S6.6地震的震前热异常整体从NW的塔斯特-巴尔雷克断裂附近向震中移动且呈条状;4)分析多年热异常与地震间的关系发现,TPR随震级的增大升高,即震级越高则震前发生地震热异常的概率越大,该发现对未来地震预报具有重要意义。
英文摘要	The seismic thermal anomaly has been confirmed by a large number of earthquake case studies, but the weather factor is still the limiting factor for the fine extraction of thermal anomalies.In the past,in order to eliminate the short-term noise of meteorology,the spatial domain difference value was used to replace the temperature value in the original remote sensing image,but the cloud mask will affect the spatial domain mean value,which makes the spatial domain difference value not representative.This causes thermal anomalies due to differences in cloud masks and spatial distribution of temperature.In previous RST studies,the thermal anomaly thresholds were judged to be different values of 1.6,2,3,and 4,and there was no stable value.When the number of background fields changes under the same threshold, the thermal anomaly area will change.Therefore,when constructing the background field,the time domain difference is used first and then the spatial domain difference is calculated to remove the weather influencing factors.By introducing skewness abnormal data monitoring algorithm,different sample numbers correspond to different thresholds in thermal abnormality judgment.In this experiment,the areas of 32.70° ~ 42.72°N and 96.37° ~106.65° E in Gansu,Qinghai and Sichuan were used as the study area.The new algorithm is used to analyze the spatial and temporal distribution of thermal anomalies in Hutubi M_S6.2 earthquake on December 8,2016,Jiuzhaigou M_S7.0 earthquake on August 8,2017,and Jinghe M_S6.6 earthquake on August 9,2017.Statistical analysis is made on the statistical relationship between earthquakes of magnitude 4 and above and thermal anomalies in the study area from January 1,2003 to August 31,2019.Experiments and results show that: 1)By analyzing the annual mean surface temperature map in 2004,it was found that the night temperature in Qinghai Province in the study area was lower than that in other areas,and the night temperature in the southern Gansu and desert areas in the northeast of the study area was relatively high.On June 26,2004,most of the cloudless images were in the low-temperature region of Qinghai Province,which resulted in a low average value of the spatial domain.The temperature difference between the high-temperature and cloudless regions of Qinghai Province and Gansu Province was relatively large,so the spatial domain difference caused the false thermal anomalies.The difference in time domain is calculated before calculating the difference in spatial domain,and the thermal anomaly almost disappears.Using the difference in time domain and then calculating the difference in spatial domain will eliminate the false thermal anomaly caused by the difference in temperature and spatial distribution of clouds.2)Through experiments,it is found that the skewness in different sample numbers used in this paper corresponds to different thresholds and the position and area of thermal anomalies are closest when the RST threshold is 4.5.When the RST is at a threshold of 4.5 and the number of background fields is 12,14,and 16, respectively,the thermal anomaly area becomes smaller as the number of background fields increases, but for the skewness of different thresholds corresponding to different sample numbers in the background when the number of fields is 12,14,and 16,respectively,the change in thermal anomaly area is small.It is obtained that under the premise that the number of samples satisfies the abnormality judgment,different sample numbers corresponding to different thresholds will basically keep the thermal anomaly area unchanged when the number of background fields changes,and the thermal anomaly threshold judgment stability gets stronger.
中文关键词	地震热异常 ; 偏度 ; 背景场 ; 时间域差值 ; 空间域差值
英文关键词	seismic thermal anomaly skewness background field time domain difference spatial domain difference
类型	Article
语种	中文
收录类别	CSCD
WOS类目	Geology
CSCD记录号	CSCD:6901811
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/353409
作者单位	刘文宝, 辽宁工程技术大学, 测绘与地理科学学院, 阜新, 辽宁 123000, 中国. 张继超, 辽宁工程技术大学, 测绘与地理科学学院, 阜新, 辽宁 123000, 中国. 孟庆岩, 中国科学院空天信息创新研究院, 北京 100101, 中国. 张颖, 中国科学院空天信息创新研究院, 北京 100101, 中国. 孟亚飞, 中国科学院空天信息创新研究院, 北京 100101, 中国. 卢显, 中国地震台网中心, 北京 100045, 中国.
推荐引用方式 GB/T 7714	刘文宝,孟庆岩,张继超,等. 基于偏度的地震热红外异常提取[J],2020,42(6):1509-1524.
APA	刘文宝,孟庆岩,张继超,张颖,卢显,&孟亚飞.(2020).基于偏度的地震热红外异常提取.地震地质,42(6),1509-1524.
MLA	刘文宝,et al."基于偏度的地震热红外异常提取".地震地质 42.6(2020):1509-1524.