There are quite a few horizontal wells featuring insufficient logging suite

and thus are difficult to evaluate.However

the way to effective evaluation on horizontal wells with limited logging data is of great significance to successful development of gas reservoirs.We propose a productivity evaluation method based on two parameters

which are the peak value of Gamma ray logging and the effective total hydrocarbon indicator

because for many horizontal wells in the drill sector X of Daniudi gas field in Ordos Basin

only Gamma LWD and gas logging data are available.In addition

the method proposed also employs some of the dynamic geological and production data.It effectively improves the accuracy of productivity evaluation on horizontal wells

and may be applied to logging evaluation on horizontal wells in gas reservoirs of similar type.The study shows that the Gamma peak value is an effective indicator of reservoir quality:for the reservoirs in Shanxi and Lower Shihezi Formations of the Daniudi drilling sector X

the LWD Gamma data of high production wells are characteristic of single peak statistical distribution

while that of low production wells shows double peaks or no obvious peak

which is largely related to the stability of sand bodies encountered in drilling wells.Furthermore

using the gas logging data in the drilling sector X

we evaluated the single-well productivity based on the effective total hydrocarbon indicator

and propose a gas logging indicator for commercial productivity of horizontal wells in the Shanxi and Lower Shihezi Formations.By integrating these two indicators

we established the dual-parameter evaluation method for horizontal well productivity

and made an accurate prediction on the single-well productivity of the horizontal wells in the drilling sector X.