Tangshan earthquake has precursors, but Wenchuan earthquake has precursors?

Tangshan earthquake1July 28th, 976 was more than 65438+3: 42: 53.8 seconds. In Tangshan and Fengnan, Hebei Province, China (east longitude 1 18.2, north latitude 39.6), the intensity is 7.8 on the Richter scale (7.5 moments), the epicenter intensity is VII degrees, and the focal depth is 23 kilometers. The earthquake lasted about 12 seconds. The feeling range reached 14 provinces, municipalities and autonomous regions, among which Beijing and Tianjin were seriously affected. The energy generated by a strong earthquake is equivalent to the explosion of 400 Hiroshima atomic bombs. The whole city of Tangshan was razed to the ground in an instant, and the city's transportation, communication, water supply and power supply were interrupted. There was no small-scale foreshock in the Tangshan earthquake, and it happened in the early morning when people were asleep, which made most people unprepared, causing 242,769 deaths and164,000 serious injuries, ranking first in the history of earthquakes in the world in the 20th century. Direct property losses amounted to more than 3 billion yuan. Wenchuan earthquake, also known as the 2008 Sichuan earthquake, occurred on May 6, 2008 12 (Monday) (UTC+8) 14:27:59.5. The epicenter was located at the junction of Yingxiu Town and Xuankou Town, Wenchuan County, Aba Tibetan and Qiang Autonomous Prefecture, Sichuan Province, China, 79 kilometers west-northwest of Chengdu, the capital of Sichuan Province. According to the data of China Seismological Bureau, the surface wave magnitude of this earthquake reached 8.0Ms, and the moment magnitude reached 8.3Mw (according to the data of USGS, the moment magnitude was 7.9Mw), and the damaged area exceeded 654.38+ million square kilometers. The earthquake intensity may reach 1 1 degree. The earthquake affected more than half of China and many Asian countries and regions. The earthquake was felt in Liaoning in the north, Shanghai in the east, Hong Kong, Macao, Thailand and Vietnam in the south and Pakistan in the west. As of September 8, 2008 12, the Wenchuan earthquake has caused 69,227 deaths, 374,643 injuries and 17923 missing. It is the most destructive earthquake since the founding of the People's Republic of China, and it is also the most serious casualty after the Tangshan earthquake.