Ogaden Basin is the largest sedimentary basin in Ethiopia covering an area ofrnapproximately 350,000 sq. km and having an estimated sediment thickness of over 7 kmrnin the deepest part. The Karoo sequence which lies at the base of the sedimentary sectionrnis a Permian - Triassic terrigenous clastics deposited in a tensional to trans-tensionalrntectonic setting. The sequence thickness reaches 3000 m and contains proven gas reservernin excess of 6 TCF. Previous studies of the Karoo sequence focused primarily on thernsedimentology and lithostratigraphy of the section. This study presents the firstrnintegrated sequence stratigraphic analysis of the Karoo section using seismic and wellrndata and in addition investigates the hydrocarbon potential of the sequence.rnThe first phase of the work involved seismic data reprocessing. Seismic data quality in thernstudy area is generally inadequate for sequence stratigraphic analysis. Hence, in therncurrent study, seismic lines with a total length 296 kms were reprocessed to improvernreflectivity and continuity, especially in the Karoo section. Analysis of shot gathersrnshowed that proper removal of source related groundroll and amplitude burst noises wasrnimperative to recover reflections. The trace edit and spike and burst edit tools were usedrnto effectively remove noise bursts and the groundroll noise was attenuated using linearrnRadon transform. Surface consistent amplitude correction, predictive deconvolution andrnvelocity analysis looped with residual statics are among the other processing stepsrnapplied to the data. Stacking was done using the second pass velocity field which was alsornused in post stack migration of lines. The result of reprocessing, compared with therniiirnprevious processing, showed improvements mainly in recovering reflectivity in the Karoornsection as well as in continuity of reflections.rnThe reprocessed seismic lines, two additional seismic sections and well data were used torndefine four second order sequences and at least four higher order sequences in thernuppermost sequence. The transgressive systems tract and the overlying highstandrnsystems tract separated by a maximum flooding surface constitute the bulk of thesernsequences. The dominant depositional systems in systems tracts include shallow andrndeep lacustrine, fluvio-deltaic and possibly sublacustrine fans and turbidites. Our studyrnsuggests that the major control in creation of accommodation space is related to wrenchrntectonics which gave rise to narrow pull apart sub-basins and their surrounding steeprnflanks. These structures are oriented NE-SW to E-W. The study also suggests a number ofrnpotential hydrocarbon plays associated with the identified systems tracts.rnAt the last phase of the work, 1D and 2D basin and petroleum system modeling wasrncarried out to analyze the hydrocarbon potential of the Karoo sequence based on wellrndata and the new sequence stratigraphic interpretation. The modeling process simulatesrnthe basinâ€™s thermal, hydrocarbon generation and accumulation history. The models,rncalibrated with Vitrinite reflectance (Ro) and temperature data, show that heat flowrntrends are similar throughout the study area with the exception of the western basinrnmargin area which has consistently higher values. 2D modeling result shows peakrntransformation in sequence two, three and bottom of sequence four source rocks wasrnreached during upper Permian, middle Triassic and middle Jurassic respectively and thatrnat present all potential source rocks have reached complete transformation. Simulationrnresults also show potential reservoir targets are dominantly gas charged in the deeperrnparts whereas shallower targets are filled with high GOR oil.