The upper Lower Carboniferous, Serpukhovian (=Chesterian) productide brachiopod genus Gondolina , from China, is made the type for the new subfamily Gondolininae in the Aulostegidae. Sectioned specimens reveal an unusual posterior dorsal flap of shell partially covering the ventral interarea.
A belt of deformed Permo-Carboniferous sedimentary rocks in Inner Mongolia represents an orogenic zone between the North China and Siberian blocks. The belt apparently contains accretionary terranes thrust onto the margins of both blocks, with scattered ophiolite/blueschist suites indicating the consumption of oceanic crust at least slightly older than the age of deformation. Upper Carboniferous to Lower Permian strata in central Inner Mongolia show both sedimentological and paleontological differences from Middle and Upper Permian rocks. In comparison with pre-Middle Permian rocks, younger Permian strata: (1) contain less laterally extensive limestone and more lensoidal carbonate in clastic sections; (2) contain a higher percentage of coarse clastic material; (3) grade upward from marine to terrestrial deposits; (4) contain fauna indicating more restricted circulation, particularly toward the western part of the belt; and (5) contain fauna that are consistent with, but do not require, northward movement of the North China block during the Permian. These differences indicate continued compression and progressive shallowing, and ultimate destruction, of the ocean basin between North China and Siberia. The lithologic and paleontologic similarity of Upper Carboniferous strata on both sides of proposed suture zones, however, is consistent with the possibility that virtually all Permo-Carboniferous sediments in central Inner Mongolia were deposited along the margin of the North China block, possibly on continental crust above an older suture zone. Thus, closure of an ocean basin by subduction of oceanic lithosphere in the Permo-Carboniferous may have been north of Inner Mongolia.
Dolostones occur on the top of the reef core, reef front and back reef sequences of the Upper Permian The Changhsingian reef in Ziyun County, Guizhou Province, southwestern China. Comprehensive study on them reveals that these dolostones are of the supratidal Sabkha genesis; (1) All have δ18O values higher than those of their precursor limestones, (2) All have Sr and Fe contents similar to those of known typical supratidal Sabkha evaporative finely crystalline dolostones from a well in the Ordos Basin, Shaanxi -Gansu -Ningxia provinces, China, (3) All are composed of finely crystalline euhedral-subhedral dolomites, (4) All occur on the top of the reef core, reef front and back reef, (5) Algal laminated structure, bird-eyes, mudcracks and crustose limonite occur in the reef front and back reef. These features indicate that this reef was once emerged at the terminal Permian. The emergence of the Changhsingian reefs at the terminal Permian might be caused by sea-level drop. This inference is in agreement with the sedimentary environmental changes in China and North Italy. The Cadore Basin in North Italy changed from a mid-shelf environment to a meteoric phreatic diagenetic environment at the end of the Permian. During the Permian-Triassic transition, the water depth of the Lower Yangtze Basin changed from more than 1,000 meter (below the carbonate compensation depth) to less than 1000 meter (near the carbonate compensation depth). The sea-level drop indicated by evidence from not only reefs but also non-reef deposits might be one aspect of the mechanism that caused the mass extinction of biota at the end of Permian.
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