underwater gradient

It describes the features of floor slope of alluvial sunstone/aventurine mine in different ore areas and the different sections of the same ore mine.

阐述了不同矿区及同一矿床不同地段的河流冲积砂金矿床底板坡度的特征 ,以矿区实例说明了由于存在底板坡度 ,故采金船选用不同的开采路线时 ,采池水的渗漏量相差较悬殊 ,对矿床开采有较大影