Stratigraphic forward modeling (SFM) is a numerical approach used to reconstruct sedimentary basin evolution by simulating the infilling and tectonic evolution process of strata. The challenge is that existing approaches inevitably require trade-offs among modeling fidelity and computational cost. We present a novel clastic stratigraphic forward modeling (CSFM) approach to reducing computational cost while retaining key flow and transport behaviors relevant to stratigraphic architecture. In CSFM, Lagrangian water particles affect momentum and sediment, while a fixed Eulerian grid stores topographic elevation and lithologic fractions. A simplified form of the Navier–Stokes equations is proposed to compute the trajectories of fluid particles, which can greatly reduce the computational cost. Sediment dynamics are represented by coupled suspended load and bedload modules. To validate CSFM, we constructed a synthetic alluvial fan model and performed stratigraphic forward modeling on it. Five lake-level cycles were imposed and results showed that cyclic sand–clay couplets and isolated channel sand bodies were formed during repeated progradation and backstepping. These results are consistent with established sedimentological knowledge, confirming the geological plausibility of CSFM.

This study investigates the combined effects of partial saturation and aligned fractures on P- and S-wave velocities and anisotropy in tight sandstones. Ultrasonic measurements (0.5 MHz) were conducted on three synthetic samples with a matrix porosity of 11.7% ± 1.2% and controlled fracture densities (0%, 3.12%, and 6.24%) under a full range of water saturation rate (S_w), from dry to fully water-saturated. Experimental results reveal that for fractured samples, the P-wave anisotropy parameter ε increases sharply as S_w decreases from 100% to approximately 60%, followed by a gentler variation at lower saturation. In contrast, fracture-induced shear-wave splitting (SWS) is predominantly governed by fracture density and exhibits weak dependence on S_w. To interpret these observations, we developed a coupled rock physics framework by integrating the MJGW partial saturation model with the Galvin fracture model, introducing a distribution coefficient to account for the non-uniform water distribution between the matrix and fractures. The coupled model accurately explains the V_p and SWS trends, while the overestimation of V_s and ε is attributed to near-dry surface effects at grain contacts and mutual interaction between fractures. This work provides experimental data and modeling insights for seismic-based characterization of multiphase-fluid-saturated fractured reservoirs.