In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orientation and edge of the reflections. The information is usually estimated from seismic data with full frequency bandwidth. When the data has a very low signal to noise ratio (SNR), the noise usually reduces the estimation accuracy. For seismic data with extremely low SNR, the dominant frequency has higher SNR than other frequencies, so it can provide orientation and edge information more reliably than other frequencies. Orientation and edge are usually described in terms of apparent reflection dips and coherence differences, respectively. When frequency changes, both dip and coherence difference change more slowly than the seismogram itself. For this reason, dip and coherence estimated from dominant frequency data can approximately represent those of other frequency data. Ricker wavelet are widely used in seismic modeling. The Marr wavelet has the same shape as Ricker wavelets in both time and frequency domains, so the Marr wavelet transform is selected to divide seismic data into several frequency bands. Reflection apparent dip as well as the edge information can be obtained by scanning the dominant frequency data. This information can be used to selectively smooth the frequency bands (dominant, low, and high frequencies) separately by structure-oriented edge-preserving smoothing technology. The ultimate noise-suppressed seismic data is the combination of the smoothed frequency band data. Application to synthetic and real data shows the method can effectively reduce noise, preserve edges, improve trackable reflection continuity, and maintain useful information in seismic data.

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The varied terrain and complex subsurface structure in the foothill segment of fold and thrust belts results in low-quality seismic data. Therefore, a structural model built only on the basis of seismic will have low reliability and be nonunique. To solve these problems, we have developed a comprehensive modeling method for foothill zones that combines gravity, magnetic (MT), electric, and seismic data. Information from gravity, MT, electric, and seismic data is fully used in each step of modeling. This reduces the nonuniqueness and guarantees the rationality and reliability of the tectonic model. The core of this procedure is simultaneous joint inversing gravity, MT, electric, and seismic multiparameters, which improves the accuracy of velocity model and results in a higher quality of seismic image. The Hala’alate Mountain area in the Junggar Basin, western China, is chosen as the application place, and the process of modeling is evaluated in detail; the structural model is proven to be correct by drilling data. Our method is more accurate and reliable than methods only using seismic data to build a geologic model in foothill zones.

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Depending on different seismic frequencies and reflection interface information of sedimentary bodies, the core technologies involved in sedimentology had been introduced into clastic transpressional basins developing in Junggar Basin in the ways of the macro (seismic geomorphology) and micro (seismic lithology) to design a data interpretation process in double domain (time domain and Wheeler domain) in minimum isochronal strata unit. The isochronal horizon slice technique suitable for a variety of sedimentary models had been improved. The combination calibration and conversion of drilling data and seismic data were first realized according to unchangeable double domains time and depth relationship. A set of reservoir description technique was preliminary formed to be applied to lithologic identification, palaeosedimentary environment recovery, reservoir evolution and favorable reservoirs description basing on the analysis of stratigraphic sedimentary rhythm, which had been applied to the center of Junggar Basin and confirmed to be a worthwhile technique depending on seismic sedimentology for accurate reservoir description.