الفهرس 
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Abstract
The Abu-Rudeis-Sidri field is located on the eastern coast of the Gulf of Suez. The field is considered as the north westerly extension of Gebel Nezzazat titled fault block. The rationale for the research comes from the realization that there is a heterogeneous distribution of the productive wells, hydrocarbon phases (crude oil with different API and sulfur contents, depths and rates of production) in the Abu Rudeis-Sidri Oil Field, Gulf of Suez-Egypt. An integrated 1D model on seven wells has been performed to simulate the multi-tectonic phases in order to define the multiple thermal regimes in the Abu Rudeis-Sidri oilfield. Best accordance between measured and calculated present-day temperatures was achieved with present-day heat flows in the range of 42-55 mW/m2. Reconstruction of the thermal and burial histories provided information on the paleotemperature profiles, the timing of thermal activation as well as the effect of the Oligo-Miocene rifting phases and its associated magmatic activity. The burial histories show that the pre-rift subsidence was progressive but modest, whereas the syn-rift was more rapid (contemporaneous with the main rifting phases and basin formation). Finally, the early post-rift thermal subsidence was slow-moderate in contrast to the late post-rift thermal subsidence which was moderate to rapid. The simulated paleo heat flow illustrates a steady state for the pre-rift phase and non-steady state (transient) for syn-rift and post-rift phases. Three geothermal regimes were recognized, each of which is associated with a specific geological domain. 1) A lower geothermal regime reflects the impact of stable tectonics (pre-rift). 2) The higher temperature distribution reflects the syn-rift high depositional rate as well as the impact of stretching and thinning (rifting phases) of the lithosphere. 3) A local higher geothermal pulse due to the magmatic activity during the Oligo-Miocene time (ARM-1 and Sidri-7 wells). Paleo-heat flow values of 100mW/m2 (Oligo-Miocene rifting phase) increased to 120mW/m2 (Miocene rifting phase) and lesser magnitude of 80mW/m2 (Mio-Pliocene reactivation phase) have been specified. The present-day surface heat flow ranges from 42 to 55mW/m2, with higher values assigned for the ARM-5 well that is characterized by thick highly thermal conductive basin-fill sediment; (i.e. the South Gharib Formation). Whereas, the lower value specified for the Sidri-8 well is associated with thick lower thermal conductive basin-fill sediment (i.e. the Rudeis Formation (565m) and the Post Zeit Formation (1360m)). The predicted oil window of the Duwi-S organofacies obtained at the same time (~5.8Ma) but at differed burial depths. The differences resulted from the variation in the eroded and preserved thickness of the pre-Duwi-S sediments (underburden). In addition, the present-day depth of burial and the eroded thickness of the post-Duwi-S sediments (overburden) play an important role. Moreover, the contrast in lithology and its physical properties especially the bulk thermal conductivity is critical factors as well. The modeled maturity evolution of the Thebes-S organofacies reveals that maturation occurred as a result of the combination of two main reasons. Firstly the initial increase in the basal heat flow and increased sedimentation rates due to the Miocene rifting phases and the subsequent post-rift thermal subsidence. Secondly, the increased heat flow value associated with the Pliocene rifting (~6-5.2Ma) as well as the post-rift thermal subsidence. There are no expulsions from the Thebes-S organofacies, where the generated hydrocarbon completely absorbed by organic matter resulted in a minor amount of free hydrocarbon to be accumulated in the source rock for further gas generation. The Thebes-S required ~ 900m more to the present-day burial depth to initiate the expulsion, which compensated by the eroded thickness from 1450m to 633m at ARM-6 and ARS-1, respectively. The thermal maturation and hydrocarbon generation (oil and gas windows) of the Thebes organofacies are affected by the 2nd phase of the post-rift thermal subsidence.