Special geological conditions including karst cave, flow sandseam and underground river are encountered during construction of railway and highway engineering.
在公路铁路基础建设工程中，常会遇见溶洞、流砂层、地下暗河等特殊地质情况。
2
When the seam was extracted, water from the sand layer penetrated into some coal faces.
煤层开采后，一些工作面出现了砂层水渗入井下的现象。
3
This paper discussed the evolvement characteristics of sand bodies of the fourth coal bearing interval and its influence on No. 13-1 coal-seam thickness in Huainan coal field.