Solution Spot Genetic Mechanism of Majiagou Formation in Ordovician of Ordos Basin
- Received Date: 2002-04-08
- Rev Recd Date: 2002-07-01
- Publish Date: 2003-06-10
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Key words:
- Ordos Basin /
- Ordovician Majiagou Formation /
- evaporative marginal marine /
- karst solution spot /
- mechanism
Abstract: The weathering crust of Majiagou Formation in Ordovician of Changqing Gasfield in Ordos Basin is the major pay zone with the evaporated marginal sea facies. Solution spots and holes with millimeter and centimeter size are developed and its occurrence, composition and fillings in the holes are very complex. Some of them have multi-stage fillings such as gypsum, quartz, calcite, dolomite, kaolinite and pyrite,and so on. The lower part of the solution hole remains dolomite crystalline just like geopetal structure of vadose sands in the clastic rock. As shown, the solution spots are formed not only with suitable lithofacies, paleogeographic environment and complexed evolutional genetic history, but also the karstification related to original deposit and different geologic historical stages.
Citation: | DI Ling-jun, YANG Cheng-yun, YANG Yi-hua, JI Xiao-lin, BAO Hong-ping. Solution Spot Genetic Mechanism of Majiagou Formation in Ordovician of Ordos Basin[J]. Acta Sedimentologica Sinica, 2003, 21(2): 260-265. |