多年冻土砂金矿分层剥离自然解冻法解冻周期确定

多年冻土砂金矿的开采，解冻是关键，而解冻周期的确定是砂金开采的重要课题之一，我国普遍采用分层剥离自然解冻法解冻矿体，但对其解冻周期的确定研究尚不完善，一般采用经验法确定解冻周期，采用这一方法缺少科学依据，文中推荐采用斯蒂苏公式计算解冻周期并结合实例说明如何应用这一公式确定解冻周期。

The defining of thawing cycle of natural thawing method in the slicing of placer gold deposit in permafrost horizon

Thawing behavior is one of the keeypoints of mining placer gold in permafrost horizon.The defining of thawing cyde is one of the impovtant problems.The natural thawing method was usually used to thaw orebody in the slicing of placer gold in this country,however the researches on the defining of thawing cycle were not perfect.In general,the experiential method was adopted to define the thawing cycle,however this method was short of scientific basis.This paper employed Stiffen Formula to reckon thawing cycle and gave example to expound the application of Stiffen Formula.