Seismic surveys are crucial for investigating subsurface geological formations and require significant logistical and economic resources. This study explores the reuse of legacy seismic surveys from the Granada Basin conducted by the Chevron Oil Company in the mid-1980s to gain new geological insights. In a previous paper, data from two deep boreholes and 30 epochal seismic sections were recovered and reprocessed using Machine Learning, and this work interprets the results to generate three complete pseudo-three-dimensional models of the entire basin: a P-wave velocity model, a sedimentary sequences model, and a fault systems model. The sedimentary sequence model identified five distinct depocenters with varying sediment compositions throughout the basin. The study found a progressive decline in sediment accumulation rates over time, from 0.18 mm/yr in the Tortonian to 0.10 mm/yr in the Pliocene-Quaternary. This trend reflects changes in the sedimentary system, moving from transitional platforms to regression and transgression episodes and finally to a stable continental state. The differences in sediment accumulation rates suggest that greater disparities are linked to intense tectonic activity, while lower differences indicate reduced tectonic activity and a consistent sedimentary ratio since the Pliocene. Additionally, 17 new faults were detected. Using the fault model and seismic activity data from 1984 to 2023 provided by the Andalusian Institute of Geophysics (IAG), a hazard analysis was performed based on the maximum magnitude supported by each fault, demonstrating the value of reusing vintage seismic data to update geological models and improve our understanding of subsurface formations and seismic hazards

We investigate the origin of a long-lived earthquake cluster in the Fars arc of the Zagros Simply Folded Belt that is co-located with the major Shanul natural gas field near the small settlement of Khalili. The cluster emerged in January 2019 and initially comprised small events of w 5.4 and 5.7 earthquakes, which were followed by > 100 aftershocks. We assess the spatio-temporal evolution of the earthquake sequence using multiple event hypocenter relocations, waveform inversions, and Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR) measurements and models. We find that the early part of the sequence is spatially distinct from the June 9, 2020 earthquakes and their aftershocks. Moment tensors, centroid depths, and source parameter uncertainties of fifteen of the largest (Mn ≥ 4.0) events show that the sequence is dominated by reverse faulting at shallow depths (mostly ≤ 4 km) within the sedimentary cover. InSAR modelling shows that the Mw 5.7 mainshock occurred at depths of 2–8 km, with a rupture length and maximum slip of ~20 km and ~0.5 m, respectively. Our results strongly suggest that the 2019-2020 Khalili earthquake sequence was influenced by the operation of the Shanul field, making these the first known examples of gas extraction anthropogenic earthquakes in Zagros. Understanding the genesis of such events to distinguish man-made seismicity from natural earthquakes is helpful for hazard and risk assessment, notably in Iran which is both seismically-active and rich in oil and gas reserves.