Distribution regularity and formation mechanism of gas and water in the western area of Sulige gas field, NW China

Abstract

Serious water production and the confusion about the distribution regularity and formation mechanism of gas and water affect the progressive development in the western area of Sulige gas field. Making use of drilling, logging, and testing data, this comprehensive study determines the gas-water distribution regularity and formation mechanism, and establishes the evolution modes of gas-water distribution. The results show that, (1) the gas-water distribution appears complementarily, and relatively water-rich area is located in the northwest; (2) source rock, reservoir physical property and structure are the key controlling factors of gas-water distribution, and formation water is distributed in areas with less developed source rocks, areas of poor properties, and structural lows within connecting bodies; (3) source rocks play a key role in controlling the distribution of gas and water, source area of low maturity is rich in formation water, while source area of high maturity is rich in gas. This research gives direction for favorable areas and well site selection in the progressive development of the gas field. Key words: Ordos Basin, Sulige gas field, gas and water distribution regularity, genetic mode, formation water