Daniudi gas field in Ordos Basin is typical tight sand gas reservoirs with low permeability

low pressure and low production rate.It has been a challenge to develop this kind of gas field economically.This paper cove- rs lithofacies

lithology

petrophysical property

pore structure and gas bearing potential of different formations.On this basis

four types of reservoirs have been identified.In terms of production rate

TypeⅠis the highest

followed by Type Ⅱand then Type Ⅲ

while Type Ⅳ has no productivity.According to the types and distribution of reservoirs

different development strategies have been adopted.Single layer production through vertical well fits TypeⅠ

whose porosity and permeability are better

net pay is thicker and production rate is higher.Commingled system through vertical well for overlapped layers suits Type Ⅱ

whose porosity and permeability are moderate

net pay is thinner and production rate of single layer is lower.Staged fracturing through horizontal well matches both Type Ⅱand Type Ⅲ with only one widely distributing layer.Applying different development strategies to different types of reservoirs

we has succeeded in improving the individual-well production rate and achieving economical development of this gas field.Annual production capacity of 25×10

8

m

3

has been built up there.