SHALLOW DJ GAS

摘要

The eastern Denver-Julesburg Basin is classic prairie country.The high rolling plains of eastern Colorado,southwestern Nebraska and northwestern Kansas usually yield crops of corn,cattle and hogs.But these days,lots of shallow gas wells are sprouting up on the grass-covered hillsides.The wells target gas in the Niobrara chalk.On the eastern flank of the basin,the Niobrara reservoir holds widespread biogenic gas deposits.The high-porosity,low-permeability chalk covers an extensive area,with commercial fields developed on sweet spots that are usually associated with structures.Since the 1970s,when development began in earnest,more than 2,900 wells have made some 470 billion cubic feet (Bcf) of gas from the Niobrara in the DJ Basin.