| 1. | The objection to the placer origin have centred around the softness of uranium compounds .
反对砂矿成因的论据主要是：铀的化合物不耐磨蚀。 |
| 2. | Gold and other heavy mineral placers are notable examples of lag deposits, but gravel and boulder bars are more common .
金和其它重矿沙虽是蚀余沉积物中值得注意的例子，然而卵石和顽石沙洲都是比较普遍的。 |
| 3. | Figure 16-20 shows the good correlation observed between the magnetic field and the gold values over a muck-covered placer in this area .
图16-20表明了此地区腐殖土覆盖下砂积矿床上面的磁场和含金量之间的良好对比关系。 |
| 4. | Dredging technology and equipment for thailand placer
泰国砂矿的船采工艺及设备 |
| 5. | Study on hydrochemical mineralization factor of gold placer
砂金水化学成矿因素探讨 |
| 6. | River placers , river quarry , acquisitions and marketing
河砂矿、河石矿、收购和销售。 |
| 7. | A place where a placer deposit is washed to extract its mineral content
砂矿开采地一个用来清洗出有用矿物的砂矿开采地 |
| 8. | Automatic detonator placer
雷管自动安置机 |
| 9. | Double pipe hammering with inside pipe sampling technology and operation for placer drilling
砂钻的双管冲击内管取心工艺 |
