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四川已知有砂金矿床约30处,矿点200余处,民采点数百处,是我国主要的砂金产区之一。凡有第四纪砂砾层分布的地方几乎都有砂金富集。造成这种成矿特点的因素有三:(1)川西大面积分布的微含金地质体是砂金最基本的初始源泉,其金含量普遍高出同类岩石丰度值一个数量级(全区平均32ppb)。它在砂金成矿中的作用远超过富含金地质体。(2)与第三纪时期准平原化相伴的红土化、类红土化作用,使基岩中的微量金富集到具有经济价值的程度。出现红土化的主要条件是炎热的气候环境。(3)第四纪以来的新构造运动在四川表现强烈。地壳间歇性的上升或上升—稳定交替,导致四川有很多的含金层位,每抬升一次之后的稳定期,就是一次砂金成矿期。
There are about 30 placer gold deposits known in Sichuan, with more than 200 ore mines and hundreds of mining sites. It is one of the major sand gold producing areas in China. Where Quaternary gravel layer where almost all the accumulation of gold. There are three factors that lead to this metallogenic characteristic: (1) The micro-gold-bearing geological bodies with large area distribution in western Sichuan are the most basic initial sources of gold, and the gold content is generally an order of magnitude higher than the similar rock (average 32ppb in the whole area) . Its role in gold-gold mineralization far exceeds gold-rich geological bodies. (2) The late-Tertiary epoch-plastification accompanied with the lateritic and clayey-like remobilization, enriching the trace gold in bedrock to the extent of economic value. The main conditions for the emergence of laterite are the hot climate. (3) The Neotectonic movement since the Quaternary had a strong performance in Sichuan. The earth’s crust intermittently rises or rises - steadily and alternately, resulting in a large number of gold-bearing beds in Sichuan. The stabilization period after each uplift is a gold-forming period.