Oil stains
... Burnt area烧坏的区域 Oil stains油迹 Scratches划痕 ...
grease stain
... 滑脂分离器 grease separator 油迹 grease stain 集油器 grease trap ...
Oil trace
... 油斑 Oil potted 油迹 Oil trace 荧光级 Order of fluorescence ...
traces of oil
... T-R switch 收发开关 traces of oil 油迹 track calculating 航迹计算 ...
油迹,原油的其中一部分,是次于“油斑”的岩心含油级别,缝洞性岩心的标志是只有10%以下的缝洞壁上见原油。