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<p>We present a study of pressure and temperature evolution in the passive continental margin under the Oman Ophiolite using numerical basin models calibrated with thermal maturity data, fluid-inclusion thermometry, and low-temperature thermochronometry and building on the results of recent work on the tectonic evolution. Because the Oman mountains experienced only weak post-obduction overprint, they offer a unique natural laboratory for this study.</p> <p>Thermal maturity data from the Adam Foothills constrain burial in the basin in front of the advancing nappes to at least 4&thinsp;<span class="inline-formula">km</span>. Peak temperature evolution in the carbonate platform under the ophiolite depends on the burial depth and only weakly on the temperature of the overriding nappes, which have cooled during transport from the oceanic subduction zone to emplacement. Fluid-inclusion thermometry yields pressure-corrected homogenization temperatures of 225 to 266&thinsp;<span class="inline-formula">^∘C</span> for veins formed during progressive burial, 296–364&thinsp;<span class="inline-formula">^∘C</span> for veins related to peak burial, and 184 to 213&thinsp;<span class="inline-formula">^∘C</span> for veins associated with late-stage strike-slip faulting. In contrast, the overlying Hawasina nappes have not been heated above 130–170&thinsp;<span class="inline-formula">^∘C</span>, as witnessed by only partial resetting of the zircon <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>(</mo><mrow class="chem"><mi mathvariant="normal">U</mi><mo>-</mo><mi mathvariant="normal">Th</mi></mrow><mo>)</mo><mo>/</mo><mrow class="chem"><mi mathvariant="normal">He</mi></mrow></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="58pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="d8ce3bb5b8d51bea1aaabe8dd1323f4c"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="se-10-149-2019-ie00001.svg" width="58pt" height="14pt" src="se-10-149-2019-ie00001.png"/></svg:svg></span></span> thermochronometer.</p> <p>In combination with independently determined temperatures from solid bitumen reflectance, we infer that the fluid inclusions of peak-burial-related veins formed at minimum pressures of 225–285&thinsp;<span class="inline-formula">MPa</span>. This implies that the rocks of the future Jebel Akhdar Dome were buried under 8–10&thinsp;<span class="inline-formula">km</span> of ophiolite on top of 2&thinsp;<span class="inline-formula">km</span> of sedimentary nappes, in agreement with thermal maturity data from solid bitumen reflectance and Raman spectroscopy.</p> <p>Rapid burial of the passive margin under the ophiolite results in sub-lithostatic pore pressures, as indicated by veins formed in dilatant fractures in the carbonates. We infer that overpressure is induced by rapid burial under the ophiolite. Tilting of the carbonate platform in combination with overpressure in the passive margin caused fluid migration towards the south in front of the advancing nappes.</p> <p>Exhumation of the Jebel Akhdar, as indicated by our zircon <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M10" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>(</mo><mrow class="chem"><mi mathvariant="normal">U</mi><mo>-</mo><mi mathvariant="normal">Th</mi></mrow><mo>)</mo><mo>/</mo><mrow class="chem"><mi mathvariant="normal">He</mi></mrow></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="58pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="2657dacc3c136e36ed8984af5e5cc5e5"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="se-10-149-2019-ie00002.svg" width="58pt" height="14pt" src="se-10-149-2019-ie00002.png"/></svg:svg></span></span> data and in agreement with existing work on the tectonic evolution, started as early as the Late Cretaceous to early Cenozoic, linked with extension above a major listric shear zone with top-to-NNE shear sense. In a second exhumation phase the carbonate platform and obducted nappes of the Jebel Akhdar Dome cooled together below ca. 170&thinsp;<span class="inline-formula">^∘C</span> between 50 and 40&thinsp;<span class="inline-formula">Ma</span> before the final stage of anticline formation.</p>