EXISTENCE AND SIGNIFICANCE OF MICROUMBONES IN KARST BASIN: SAMPLE FROM ORDOVICIAN KARSTIC PALEOGEOMORPHY IN ORDOS BASIN
LIU Hong-jun,JIA Ya-ni,LI Zheng-hong,ZHENG Cong-bin
Natural Gas Geoscience . 2006, (4): 490 -493 .  DOI: 10.11764/j.issn.1672-1926.2006.04.490