The 2

nd

member of the Lower Triassic Jialingjiang Formation and the 3

rd

member of the Lower Triassic Feixianguan Formation are the main gas-producing zones in TNB area

with the characteristics of deeper burial depth and thinner reservoir thickness.Although the major discoveries have been made in this area

the prediction of gas distribution remains the key factor for better exploration achievements.The spectral analysis based on wavelet transform

however

can be used effectively in gas distribution prediction.In connection with the reservoir characteristics of target area

the feasibility of gas distribution forecasting by frequency attenuation attribute is addressed by the comparison of gas logging data(total hydrocarbon detection) with frequency attenuation attribute

the reservoir forward modeling

and the interwell section examination of gas distribution.Their results indicate that different gas-bearing characteristics are exhibited horizontally and vertically in the 2

nd

member of Jialingjiang Formation and the 3

rd

member of Feixianguan Formation. The T

1

j

2

gas reservoir(sand beach reservoir)is characterized by single gas reservoir with a larger pool area

while the T

1

j

3

Formation(oolitic beach re-servoir) is the multiple and vertically superimposed gas reservoirs with a relatively smaller pool area.