The geological features and preliminary study of goldhosted breccia in Shuangwang ore deposit, Shaanxi

Gold-hosted breccia in Shuangwang or edeposit is hydrofracturing breccia.The hydrofracturing breccia is formed by deep rich-sodic and gold-hosted fluid hydrofracturing in a set of Devonian system hot-water sedimentary rich-sodic rocks.The early coaxial progressive depressing makes the forming of tectonic lens in the competent rich-sodic and incompetent rich-mud rocks; the later nocoaxial progressive shearing makes the tectonic compression fracture into extension fracture in the early tectonic lens,at the same time,the great drop of pressure leads to the hydrofractureing of deep fluid along the fracture in the rich-sodic rocks,and then produces the hydrofracturing breccia.