North China craton
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The North China craton is one of the oldest cratonic blocks in the world. It covers an area of ~1.7 million km2 across most of northern China, the southern part of northeastern China, Inner Mongolia, the Bohai Bay and the northern part of the Yellow Sea. The craton is bounded by the early Paleozoic Qilianshan orogen and the late Paleozoic to Mesozoic Central Asian orogenic belt to the west and north, respectively, and the Mesozoic Qinling-Dabie and Su-Lu ultrahigh-pressure metamorphic belts to the south and east, respectively. The basement of the craton can be divided into Eastern and Western blocks, separated by the Paleoproterozoic Trans-North China Orogen (TNCO). The TNCO is characterized by fragments of ancient oceanic crust, mélanges, high-pressure granulites and retrograded eclogites, crustal-scale ductile shear zones and linear fold belts with sheath folds. These lithotectonic elements contrast with the dominant Archaean tonalite-trondhjemite-granodiorite (TTG) gneiss domes surrounded by minor supracrustal rocks in the Eastern and Western blocks. In addition, petrographic and thermobarometric data have revealed a remarkable difference in metamorphic evolution between the TNCO and the Eastern and Western blocks. The former underwent a major metamorphic event about ~1.85 billion years (Ga) ago with clockwise P-T paths involving isothermal decompression, suggesting a collisional environment, whereas the latter experienced a major metamorphic event at ~2.5 Ga, with anticlockwise P-T paths involving isobaric cooling related to the underplating of mantle-derived magmas. These differences led some researchers to propose that the TNCO was a continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form a coherent craton at ~1.85 Ga.
The North China craton underwent a long-lived period of sedimentation with minor volcanism in the Yanshan-Taihangshan aulacogen (a fault-controlled basin) during the period 1.8-0.8 Ga, forming the Paleoproterozoic Changcheng Group, Mesoproterozoic Gaoyuzhuang Group and Jixian Group, and Neoproterozoic Qingbaikou Group. Meanwhile, the craton also experienced widespread rifting and anorogenic magmatism of the late Paleoproterozoic along the southern and northern margins, forming anorthosite-mangerite-charnockite-granite suites.
About 300-250 million years (Ma) ago the combined North China and Tarim cratons collided with Siberia to comprise the last stage in the formation of Pangaea. At 220-240 Ma, the North China craton collided with the Yangtze block along the Qinling-Dabie-Sulu orogenic belt. The Eastern Block of the North China craton underwent crustal thinning that began in the Mesozoic and is known to have reduced the thickness of the crust from 200 km to as little as 80 km.
The area of the North China craton (see: [1] and [2]) is also referred to as the Sino-Korean craton or block (see: [3]) in some references.
![[1]](http://pangea.stanford.edu/research/noble/chinasloss/chinazones2.jpg){kind=link}