China is a country of intense midland seismicity. There are many historical earthquake reports from China, the earliest dating back to 23 BC , but only very few about volcanic eruptions. The seismicity in China cannot be fully explained by plate tectonics theory. The Chine earthquakes are not only concentrated within plate-boundary zones. Most China's earthquakes in occur within the interior of the Eurasian plate.

China is a country of intense midland seismicity. Most earthquakes in China occur within the interior of the Eurasian plate.	Seismicity in China and neighboring regions. Blue dots are the epicenters of historical earthquakes before 1900 A.D., and red dots are those from 1900 to 1990. The green fault-plane solutions are from the Harvard catalog (1976–2004) without scaling. Solid lines are active faults.	The collision between the Indian subcontinent and the Eurasian continent, causing frequent large earthquakes between India and Tibet and throughout Tibet and surrounding areas (shown by circles and dots on this map).

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• 2008 Sichuan Earthquake.
• 2014-08-03 China Earthquake Yunnan.

Significant Earthquakes in China (1917 - 2010).

 

N	DATE	N	E	M	REGION	DEATHS
1.	30 July 1917	28.0	104.0	6.5		1,800
2.	13 Feb 1918	23.5	117.0	7.3	Guandong	10,000
3.	16 Dec 1920	35.8	105.7	7.8	Gansu	200,000
4.	24 Mar 1923	31.3	100.8	7.3		5,000
5.	16 Mar 1925	25.5	100.3	7.1	Yunnan	5,000
6.	22 May 1927	36.8	102.8	7.9	Tsinghai	200,000
7.	25 Dec 1932	39.7	97.0	7.6	Gansu	70,000
8.	18 Aug 1933	32.0	103.7	7.4		10,000
9.	25 July 1969	21.6	111.9	5.9		3,000
10.	04 Jan 1970	24.1	102.5	7.5	Tonghai,Yunnan	10,000
11.	10 May 1974	28.2	104.0	6.8	Zhaotong,Yunnan	20,000
12.	04 Feb 1975	40.6	122.5	7.0	Haicheng, Liaoning	10,000
13.	27 July 1976	39.6	118.0	7.5	Tangshan, Hebei	255,000
14.	12 May 2008	31.0	103.32	7.9	Eastern Sichuan*	~90,000

* Aftershocks occurred in a linear trend,~300 km long and NE-SW direction,at eastern boundary of Tibetan Plateau

Recent Earthquakes in China (information from USGS).

	DATE	N	E	M	REGION	DEATHS
15.	13 Apr 2010	33.27	96.63	6.9	Sthn Qinghai	~600
16.	06 Oct 2008	29.76	90.32	6.4	Xizang	9
17.	26 Nov 2005	29.51	115.63	4.6	Hubei-Jiangxi border region	14
18.	24 Feb 2003	39.61	77.23	6.3	Sthn Xinjiang	261
19.	03 Feb 1996	27.29	100.28	6.6	Yunnan	322

Simplified map of major geological units in continental China and their relative motion (mm/yr) with respect to stable Siberia, based on Quaternary fault-slip rates and other neotectonic data (Ma, 1989; Deng et al., 2002). Thin lines are active faults. WG—Weihe graben; SG—Shanxi graben; YR—Yinchuan rift; HR—Hetao rift; BB—Bohai Basin.

On a continental scale, the seismicity of central and eastern Asia is a result of northward convergence of the India plate against the Eurasia plate with a velocity of about 50 mm/y. The convergence of the two plates is broadly accommodated by the uplift of the Asian highlands and by the motion of crustal material to the east away from the uplifted Tibetan Plateau.The collision of the Indian plate into the Asian plate (convergence) activated faults that had both convergent and transform components to them.
The territory of China is divided into two parts in terms of seismicity, neotectonic, geodynamics. Border can be made from 105 meridian.

Cenozoic fault systems are predominantly oriented NNE and NWW, reflecting the influence from both the Indo-Eurasian collision and subduction of the Pacific and the Philippine Sea plates (Deng et al., 2002; Zhang et al., 2003). Active crustal motion on these faults, however, may be influenced by the Indo-Asian collision (Tapponnier and Molnar, 1977; Zhang et al., 2003). In the East of ~105°E, the influence of Indo-Asian collision is less clear. The rates of Quaternary crustal deformation are much lower than in western China. Major deformation, seismicity and most earthquakes in eastern China occur within the North China block. The South China block, on the other hand, is seismically quiescent.

The North China block

The North China block is one of the most active intraplate seismic regions in the world, with intense historic and modern events. Some workers have ascribed the high seismicity in the North China block to its lithospheric structures (Ma, 1989). The North China block is part of the Archean Sino-Korean craton.
The North China block is a geological province including:
- the stable Ordos Plateau and surrounding rifts;
- the North China Plain, and the coastal regions;
The surrounding rift systems include:
- the Yinchuan rift basins (YR) to the west;
- the Hetao rift zone (HR) to the north;
- the Shanxi graben (SG) to the east;
- the Weihe graben (WG) to the south.
These rift zones initiated as early as the Miocene but developed mainly during Pliocene time (Zhang et al., 1998). Neotectonic evidence shows 2–6 mm/yr lateral motions on these fault zones (Deng et al., 2002) and about ~1.2 mm/yr extension across the Shanxi graben (Zhang et al., 1998). Historic records show three M = 8 and more than 30 M = 6 earthquakes in these rift zones
The North China Plain is a region of Mesozoic-Cenozoic rift basins and uplift structures crosscut by a system of NNE- and NWW-oriented fault zones, on which many large modern earthquakes have occurred, including the 1976 Tangshan earthquake. The North China Plain is separated from the Bohai Basin (BB) and other coastal regions (collectively called the Jiaoliao block for the northern part and the Sulu block for the southern part) by the Tanlu fault zone, a major structure in east Asia and the locus of numerous large earthquakes, including the 1668 M = 8.5 Tancheng event.
The intense seismicity in the North China block, and the lack of seismicity in the South China block, may be explained primarily by the tectonic boundary conditions that produce high deviatoric stresses within the North China block but allow the South China block to move coherently as a rigid block. Within the North China block, seismicity is concentrated in the circum-Ordos rifts, reflecting the control of lithospheric heterogeneity.
North of the North China block, there is the relatively stable Siberian shield, where the major Quaternary crustal deformation is extension across the Baikal rift zone. Within China, this region is called the Dongbei or Mongolian-Alashan block; here, the Quaternary crustal deformation and seismicity are weak.

The South China Block.

The South China Block is south of the North China block and is separated from it by the Qingling-Dabie fault zone and from the Tibetan Plateau by the Longmanshan–Xianshuhe–Red River fault system. Within the South China block, Quaternary deformation is minor, and seismicity is quiescent relative to the North China block.

India has penetrated over 1500 km into Asia. The collision between the Indian subcontinent and the Eurasian continent continues today, produced the Himalaya and the Tibetan Plateau. The GPS and neotectonic studies of continental China provide useful kinematic information about the geodynamics of crustal deformation and seismicity.

Neotectonic Map of China.	Bouguer Gravity Anomaly Map of China.

Neotectonic studies in the North China block and extensive global positioning systems (GPS) measurements in China have greatly refined the knowledge of crustal kinematics. The driving mechanisms and their interplay with lithospheric structures control seismicity in China. Neotectonic studies have shown a strong influence of plate boundary processes on the diffuse crustal deformation in China and surrounding regions (Tapponnier and Molnar, 1977, 1979; Wesnousky et al., 1984; Ye et al., 1985; Burchfi el et al., 1991; Avouac and Tapponnier, 1993; Xu et al., 1993; Allen et al., 1998; Zhang et al., 1998, 2003). The GPS measurements have provided many details of crustal motion in China and surrounding regions. Consistent with neotectonic data, GPS data indicate weak crustal deformation in East Asia. The geodynamic models of different spatial scales, constrained by the GPS and neotectonic data, using to explore the major driving forces and critical boundary conditions for active crustal deformation in China and neighboring regions. Active crustal deformation in China and surrounding regions is controlled by:
- the indentation of the Indian plate;
- gravitational spreading of the Tibetan Plateau.
The direct impact of the Indian indentation is limited to western China, whereas gravitational spreading of the Tibetan Plateau has broad impact on most of East Asia. The influence of plate-boundary forces along the subduction zones around the eastern margins of the Asian continent is minimal at present but may have played an important role in early Cenozoic.

A magnitude 7.9 earthquake occurred in the Eastern Sichuan area of western China on Monday, May 12, 2008 at 2:28 PM local time. It occurred at a depth of about 19 kilometers (11.8 miles). The earthquake destroyed numerous communities, leaving an estimated five million people without housing. Severe damage was caused by landslides which dammed rivers and flooded lands upstream. The government estimated that about 70,000 people were killed as a direct result of the earthquake. The earthquake was felt throughout China and in parts of Bangladesh, India, Japan, Mongolia, Nepal, Pakistan, Russia, Taiwan, Thailand and Vietnam. Numerous strong aftershocks caused extensive damage collapsing thousands of homes and killing thousands of people.

Intensity Contour Map: USGS Map of MMI (Modified Mercalli Index) contours plotted over population per ~1 square km (see gray scale bar on top of map). The regions of integer MMI values are separated by the thick contour lines and labeled with Roman numerals.

The Sichuan earthquake of May 12, 2008, occurred as the result of motion on a northeast striking reverse fault or thrust fault on the northwestern margin of the Sichuan Basin. The earthquake's epicenter and focal-mechanism are consistent with it having occurred as the result of movement on the Longmenshan fault or a tectonically related fault. The earthquake reflects tectonic stresses resulting from the convergence of crustal material slowly moving from the high Tibetan Plateau, to the west, against strong crust underlying the Sichuan Basin and southeastern China.
On a continental scale, the seismicity of central and eastern Asia is a result of northward convergence of the India plate against the Eurasia plate with a velocity of about 50 mm/y. The convergence of the two plates is broadly accommodated by the uplift of the Asian highlands and by the motion of crustal material to the east away from the uplifted Tibetan Plateau.
The northwestern margin of the Sichuan Basin has previously experienced destructive earthquakes. The magnitude 7.5 earthquake of August 25, 1933, killed more than 9,300 people.