Integrated palynological, lithological, and geophysical analyses of the Lower Cretaceous (upper Hauterivian- Aptian) in Matruh Basin enabled conducting a high-resolution sequence stratigraphic analysis. Fluctuations of the continental/marine palynomorphs ratio reflect changes in the Tethyan 3rd order sea levels and are mirrored by eminent vertical changes in the spontaneous potential and the lithofacies. These are used with abundance of the marine phytoplanktons and opaque/translucent phytoclasts ratio to identify three 3rd order (SQ1: 132.4–120.8 Ma, SQ2: 120.8–115.2 Ma, and SQ3: 115.2–113 Ma) and seven 4th order genetic sequences and to study the impact of the allogenic and autogenic processes on their deposition. Deposition of the deltaic clastic systems tracts of the lower-middle Alam El Bueib (late Hauterivian-early Barremian) and Dahab (late Aptian) formations reflect the interaction between the regional humid climate and the Tethyan 3rd order sea levels, which superimposed the Tethyan 2nd order sea level. Interferences of
minor regional tectonics were also important. The argillaceous deposits possess large amounts of terrestrial organic matter of low hydrogen index (HI: 185.8–211.5 mg HC/g TOC) indicating gas organic facies. These deposits show relatively high organic richness (1.81–2.50 TOC wt %) due to relatively low sediment dilution and water circulation (i.e. suboxic-anoxic conditions) and high primary productivity due to high riverine nutrient
inputs.

       Deposition of the inner-middle shelf clastic-carbonate systems tracts of the upper Alam El Bueib and Alamein formations (latest Barremian-middle Aptian) reflects the interaction between the climatically induced low terrigenous influx and carbonate sedimentation due to shift to relatively dry climate, changes in the Tethyan 3rd order sea levels, and the middle Aptian regional minor uplift. These systems tracts show relatively large amounts of terrestrial organic matter, a notable marine organic matter signature, and intermediate HI (283.1–239.0 mg HC/g TOC) indicating gas/oil organic facies. The shales and siltstones are relatively organic richer (1.88–2.28 TOC wt %) than the pure and the argillaceous dolostones (1.46–1.94 TOC wt %). This organic richness is related to combined low sedimentation rates, low water circulation (i.e. dysoxic-suboxic to suboxic-anoxic conditions), and relatively high primary productivity.
      Overall, the Tethyan sea level changes, regional climate, and regional tectonics played a major role in the deposition of the organic-rich syn-rift Lower Cretaceous deposits in Matruh Basin.