1668 Shandong earthquake
The Great Tancheng earthquake (Chinese: 郯城 地震; pinyin: "Tánchéng dìzhèn)," also known as the Shandong earthquake was a major seismic event that occurred during the rule of the Qing Dynasty somewhere in Shandong Province on July 25 of the year 1668. The earthquake had an estimated magnitude of 8.5, making it the largest historical earthquake in Eastern China, and one of the largest in the world on land. The earthquake had cataclysmic implications to the region, shaking intensity was estimated to reach XII ("Extreme") on the Mercalli intensity scale, the most destructive shaking an earthquake could achieve . An estimated 43,000 to 50,000 lives were lost in the earthquake, and its effects were widely felt. The epicenter may have been located between Juxian and Tancheng County, northeast of the prefecture-level city of Linyi in southern Shandong. Geological setting. The earthquake of 1668 occurred along the Yishu Fault, which is part of the massive Tanlu Fault Zone which formed in the Mesozoic. This fault has an estimated slip rate of less than 1 to 2.6 mm/yr. The Yishu Fault runs through east China for a length of 360 km, and is part of the much longer, 2,000 -km-long Tanlu Fault Zone that trends north northeast-south southwest in eastern China. During the earthquake, the Yishu Fault produced a surface rupture for a length of 160 km, with an average offset of 9 meters. Researchers found that the slip sense of the fault was mainly dextral strike-slip with a small thrust component. A hypocenter depth of between 22 and 28 km has been suggested for the 1668 event. The same fault may have also produced a magnitude 7.5 earthquake in Haicheng, 700 km north of this event. Impact. The powerful earthquake was felt in 379 counties , 29 of which had catastrophic damage. In Ju County, many structures were totally destroyed. No building was left standing in the area with a diameter of more than 50 km. Wells erupted fountains of water and ground fissures opened, gushing out sand and water. The same was seen in Tancheng County where water shot through the air up to 10 meters high. Fissures were said to be so deep that the bottom of them could not be seen. The earthquake obliterated every home, temple, battlement and storehouse. In Linyi, no house was left standing, and black water was said to  emerge from fissures. Many nearby city had their walls fallen and some parts flooded by overflowing rivers and wells. Fissures caused water and sand to erupt, burying homes. Many livestocks also died as a result of the earthquakes.