The heavy mineral assemblages and detrital rutile geochemistry of Cenozoic sandstone at Kekeya profile near the western Kunlun Orogenic belt were analyzed. Two mineral sections were identified based on the contents and features of the heavy mineral assemblages: stable and unstable heavy mineral segment, which were divided by the bottom of Atushi group (N2a). These implied a rapid uplift in the western Kunlun in the Pliocene. The content of detrital rutile derived from metapelitic decreased, while that derived from metamafic increased with rising of the profile. This result suggests that basement rocks were denudated and deposited due to rapid uplift and erosion. The metamorphic stages of detrital rutile were mainly amphibolite/elogite and granulite facies, which may result from a differential uplifting of the Western Kunlun. Since Oligocene, the west part is higher than the eastern part and becomes the main provenance area.

Finite-difference method-single-shot record method is applied to forward-model kink-band models. Based on the analysis of forward modeling results and the features of seismic images response to the various kink-band belt models, the conclusions are summarized as follow. 1) In the seismic profile, kink-band belt is characterized by the substantial width of low-reflectivity, low-signal-to-noise zone and their sub-parallel edges in cross section, which are different from the features of the fault structure. 2) Their orientations at a high angle to layering can impact on the seismic imaging efforts. 3) Steeply or nearly vertical dipping bedding in the kink-band belt often misguide the reflection interface tracking by some overvalued and other false information. These results can provide first references for interpretation of the seismic profiles, such as identifying structural type, and distinguishing the fault from the kink-band.

Based on structural geometries, kinematic observations, and sand-box simulation results, the new interpretation explains that the Bachu fold belt in the Tarim basin is composed of detachment folds flanked by various-scale kink bands primarily unassociated with faulting. The Bachu antiform belt is characterized by the detachment fold. The detachment fold crests are bounded by kink bands, which are narrow zones of angularly folded strata. The substantial width of these kink bands, their sub-parallel edges in the outcrop cross-sections, and their orientation at a high angle to layering, as well as their organized spacing and conjugate geometry, support a kink-band interpretation. Application of sandbox models for tectonic simulate modeling regenerates kink-band development and evolution: wide-gentle detachment folding → tight detachment folding → fold pop-up → fault adjusting. The analog results strongly support that the kink-band is one of the structure types to form the Bachu fold zone.

Based on the review of rock mechanics theory and recent simulated experiment results, as well as sand-box simulation and seismic profile interpretation, the new interpretation explains that some uplifts/folds with high-angle deformation bands in the Tarim basin to be composed of folds flanked by megascopic-scale kink bands. The low-reflectivity, low-signal-tonoise zones seen in seismic profiles across the Bachu fold belt are poorly imaged sections of the folds that result from steeply dipping bedding in the kink bands. These fuzzy seismic zones show a substantial width in the seismic profile. According to the Maximum Effective of Moment Criterion (MEMC), the substantial width of these low reflectivity zones, their subparallel edges in cross section, and their orientation at a high angle to layering, as well as their organized spacing and the obtuse angle in the contraction direction of conjugate kink-bands, indicate that there are kink-band structures and kink-related folds in the Bachu uplift.