【摘要】 2013年6月2日22时23分,重庆万州吴达兵给曾佐勋发送了四川绵阳网友"光耀vision"于2013年6月1日19时38分拍摄的云图。通过吴达兵本人创建的"云地映对"法,初步识别出该云图对应龙门山地区。6月3日11时44分的电子邮件中,曾佐勋提出请吴达兵根据云地映对法"标注几个地名","帮助标出索状云汇聚中心点的经纬度,怀疑是震中位置",并提出似乎北面还有一个汇聚中心。当日15时17分,吴达兵给曾佐勋发来了标注地名和索状云汇聚中心经纬度(31.27°N,103.90°E)的云图。虽然北面的汇聚中心没有标注经纬度,但是地名很具体。2013年6月3日17时16分,曾佐勋在答谢吴达兵地名标注和汇聚中心经纬度标注的同时,提出了一个预测意见:利用绵阳网友拍摄云图和吴达兵云地映对标注,结合6月3日沿龙门山断裂带北段的(长条状)地球排气观测及卫星重力资料分析,预测震中应该在北川县陈家坝乡(31°N,104°E),震级应该在MS5.5±0.5,发震时间估计2个月内。曾佐勋的这一短期预测,显然重点考虑了北面汇聚中心。这是因为云图区北面索状云汇聚中心对应区的卫星重力异常梯度更加明显。2013年7月8日7时39分,在都江堰市与汶川县交接处靠近都江堰市一侧发生了MS4.1级地震,震中位置是31.3°N,103.6°E。与云图中南面汇聚中心相当一致。与曾佐勋预测的北面汇聚中心(31°N,104°E)相距仅50.6km。发震时间落入2个月预测值时间窗口。预测震级略高于实际地震的震级,误差0.9级。综合地震预测三要素与实际发生的都江堰地震三要素的对比分析,都江堰(MS4.1)地震是一次利用云地映对、地球排气与卫星重力异常相结合的成功短期预测。值得注意的是,云团中的两组索状云形成两个汇聚中心。其中一个汇聚中心已经发震,另一个汇聚中心可能孕育着下一个中、强地震。本文初步认为,弧形索状云是由于局部地面超低频震荡导致水蒸气和尘埃形成波纹。综合构造背景、卫星重力异常和该区的震源机制解分析认为,都江堰(MS4.1)地震的发震断层为北川—映秀断裂,与汶川MS8.0地震发震断层相同,为逆冲兼右行走滑性质。都江堰地震是汶川(MS8.0)地震的余震,二者具有相同的成因机制:印度板块向北推挤作用下,松潘-甘孜地块向东推覆到四川盆地之上,引起北川—映秀断裂逆冲兼右行走滑活动,造成中地壳密度突变的差异流变区积累能量突然释放。更多还原

【Abstract】 At 22:23 of June 2,2013,Wu Dabing from Wanzhou,Chongqing emailed Zeng Zuoxun a cloud picture taken by a netizen,brilliance vision,from Mianyang,Sichuan at 19:38of June 1,2013.He primarily identified the cloud picture corresponding to the Longmenshan area by using the‘correspondence between cloud and ground’method created by himself.In the email at 11:44of June 3,2013,Zeng Zuoxun asked Wu Dabing‘to label a few place names’ and‘to label the longitude and latitude of the converging center of the rope clouds,guessing it will be an epicenter’,and presented that there was another converging center at the north part of the picture area.At 15:17of the same day,Wu Dabing emailed Zeng Zuoxun the cloud picture labeled some place names and the longitude and latitude(31.27°N,103.90°E)of the south converging center of the rope clouds.There is a definite place name at the north converging center although no longitude and latitude labeled there.At 17:16,June 3,2013,in his reply email expressing appreciation to Wu Dabing for the labeling of the place names and the longitude and latitude,Zeng Zuoxun made a prediction,on the basis of the cloud picture labeled,the strip degasification along the north part of the Longmenshan fracture zone and the satellite gravity anomalies of the area,that the epicenter would be in(31°N,104°E),the magnitude would be in MS5.5±0.5,the occurring time would be in 2 months.At 7:39,July 8,2013,an earthquake occurred at the border between Dujiangyan city and Wenchuan county(31.3°N,103.6°E)with magnitude of MS4.1.We name it Dujiangyan earthquake in the article.The epicenter is in accordance with the south converging center of the rope cloud and with only a distance of 50.6km from the predicted epicenter.The occurring time of the Dujiangyan earthquake fell into the time window of the two-month prediction.The magnitude of the Dujiangyan earthquake is a little bigger than the magnitude predicted with a difference of MS0.9.The comparison between the three key elements of the predicted earthquake and the Dujiangyan earthquake indicates that this is a successful short-term prediction with the observation of earthquake cloud and degasification of the earth and the analysis of the satellite gravity anomalies.It is worth to note that the two sets of rope cloud consisted of two converging centers.At one center of them the Dujiangyan earthquake occurred and at the other one there will still be the possibility to occur a next middle-strong earthquake.Aprimary assumption is that the arcuate rope clouds are formed due to the super-low vibration of the local ground surface acting on the water vapour and dust in the sky.On the basis of the comprehensive analysis of the tectonic setting,satellite gravity anomaly and the focal mechanism in this area,we consider that the BeichuanYingxiu right-lateral thrust fault is the earthquake-triggering which triggered the Wenchuan MS8.0earthquake.We think that the Dujiangyan MS4.1earthquake is an aftershock of the Wenchuan MS8.0earthquake and both have the same formation mechanism.Under the northward indentation of the India Plate,the Songpan-Ganze Block was pushed eastwards to Sichuan Basin,causing Beichuan-Yingxiu thrusting with right-lateral slip and resulting in a sudden release of the energy accumulated at the edge of the boundary between differential rheological layers.更多还原