The Lower Permian Xiashihezi Formation in the Ordos Basin, China, is a quartz-sandstone reservoir with low porosity and low permeability. We have acquired 3D seismic data and well data from 18 vertical and four horizontal wells to indicate the potential of seismic attribute analyses in locating seismic sweet spots for lateral placement of horizontal wells. Using the analytic wavelet transform with a Morse wavelet, the integration of high tuning spectral components, high sweetness and high spectral attenuation helped us to estimate the distribution of gas-bearing tight sands in the Xiashihezi Formation. Our results revealed that the principal target of horizontal drilling and production was gas-bearing massive point bars in the braided river delta setting of the Ordos Basin. The integrated workflow of the seismic attribute analysis contributes to the optimal horizontal well planning by mining and exposing critical geological information of a tight gas sand reservoir from within 3D seismic data.

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