Discussion on Texture Types and Geologic Origin of Stone Screen from Qingjiang,Hubei Province

Stone screen from Qingjiang has been a new kind of view stones in recent 20years，which originates from grey quartz sandstone of Middle Devonian Yuntaiguan Formation.The textures on the surface of the stone screen from Qingjiang are the key factor of its ornamental value，and there are three kinds，including linear texture（fractures），banded texture（beddings）and comb texture（the infiltrating texture with convex top surface）.Through the field work and synthesizing petrology features，microscopic texture and geochemistry features，the article focuses on the geologic origins of the textures.Fractures are taken shape from the faults formed during or after Yanshan movement.Beddings originated at the same time of Yuntaiguan Formation sedimentation.Comb texture is probably caused by vadose foreign matter along the bedding surface during the late diagenesis，before Yanshan movement，though it needs further proof.The fuchsia or grayish－green bands of the three kinds of textures are caused by irony or manganic matter carrying by surface and ground water precip－itating in porosity.During neotectonics period，the original rock was put to the river and became stone screen from Qingjiang by washing and erosion.