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Reconstructing meandering paleo-channels is attracting global research attention. We implemented a novel method by comprehensively integrating migration models and sedimentary structures. Firstly, the migration architectures of the corresponding characteristics in planform and cross-sectional models were summarised as expansion, translation, expansion and translation, expansion and downstream rotation, constriction and downstream rotation, and expansion and countercurrent rotation models. Secondly, full continuous core data from 270 dense drilling wells were collected from the Daqing Oil Field in the Songliao Basin, China, providing information on rock textures, sedimentary cycles, and boundary information for the two layers being studied. Through a comprehensive analysis of dense drill cores and logging data, the abandoned channels and the initial and final channel centrelines were identified. Consequently, four profiles, including one longitudinal and three transverse sections, were constructed to reveal the cross-sectional structures and planform migration architecture. Profile interpretation revealed the evolution from the initial channel centreline to the final centreline. Using a method of rational interpolation, we were able to reconstruct the migration architecture of the meandering channels. The results showed that the average ancient bankfull width (W c ) was approximately 100 m, a single meandering belt was 800 m, the radius of the curvature was 250 m, the length of the channel bend was 700 m, the average meander wavelength was 1300 m, the sinuosity was 3.0, and the annual average discharge rate was 450 m 3 /s. Furthermore, we compared the results from empirical equations, which verified that our reconstruction is both feasible and potentially widely applicable.

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The meandering process has always been the topic through years and still remains a lot of unsolved mysteries. One of the most important focus is the migration architectures and models that the meandering channels follow. This article chooses the Nowitna River as the study object of the typical meandering river with high migratory processes. Though the high-resolution historical satellite images by the techniques of Google Earth and ACME Mapper, 50 meanders in the river is studied and 6 of which are chosen for meticulous characterization. During the process, the planform structure of meandering channel is re-examined and 29 kinds of architecture elements are systematically established. More importantly, in order to make a fine quantitative characterization of the channel structure of meandering river, 5 kinds of characterization parameters are proposed, extraordinarily, the parameters of the difference of along-current deflection angle, a difference of counter-current deflection angle, and expansion coefficient, these three are firstly brought forward and applied introduction. In addition, the conception of sinuosity index and curvature are also different from the original definition. Though these architectures elements the meandering process and migration structure of the Nowitna River is demonstrated. 6 kinds of planform migration structures is revealed with the quantitative characterization of characterization parameters and 9 species of meandering channel migration patterns are concluded and discussed.