Bertram Maduka Ozumba is currently on early retirement after rising to the position of Head of Geological Services in Shell Petroleum Development Company of Nigeria Ltd., Nigeria. He is a well-known Philanthropist and a seasoned Manager and Geoscientist with strong technical background, broad experience and leadership roles in exploration geology. He has extensive expose and experience to a broad range of multicultural working environments for which he has positively adapted. He is a Member of several professional bodies including the American Association of Petroleum Geologist (AAPG), Nigerian Association of Petroleum Explorationist (NAPE) where he is a Fellow of the Society, Nigerian Mining and Geosciences Society (NMGS), Council of Registered Miners and Geoscientists of Nigeria (COMEG), Society of Petroleum Engineers (SPE) and a Certified Petroleum Geologist (CPG) of the United States of America. He has published and continues to publish several scholarly papers in international and local journals and has served either as Editor or Reviewer in journals.
The prolific Niger Delta basin is a mature petroleum province. Therefore, further prospectivity in the basin lies within deeper plays which are high pressure and high temperature (HPHT) targets. One of the main characteristics of the Niger Delta is its unique diachronous tripartite stratigraphy. Its gross onshore and shallow offshore lithostratigraphy consists of the deep-seated Akata Formation and is virtually exclusively shale, the petroliferous paralic Agbada Formation in which sand/shale proportion systematically increases upward and at the top, the Benin Formation composed almost exclusively of sand. This stratigraphic pattern is not exactly replicated in the deep offshore part of the delta. The downward increasing shale percentage in the older and deeper parts of the basin poses a great problem to drilling. Increasing shaliness usually leads to wellbore instability and such other problems as pack-offs and stuck pipe. These hazards are the main causes of non-productive time in expensive deep-water or high temperature and high pressure (HPHT) drilling operations. Moreover clay mineral diagenesis generates mixed layer clays at higher temperatures and this tends to cause overpressures that may lead to disastrous kicks, losses and even blowouts. Predicting and managing drilling in such over-pressured or problem sections will form a major part of the evaluation for exploration and development in these parts of the delta. A formation sensitivity test consisting of the detailed study of the influence of various ions on the degree of formation damage of one of the main producing fields in the eastern Niger Delta has been studied. Analytical results of clay mineral composition obtained using X-ray diffraction (XRD) methodology were successfully applied to predict the various types of clay minerals present and hence intervals problem of shales. Further experimental formulations derived using Capillary Suction Time (CST) tests found that addition of 7% KCl to the original water based drilling fluid made drilling through the problem sequences easier leading to very good cost savings and compliance with the Nigerian environmental regulations. The operator has planned deeper drilling and further development of the field.
Forough Ameli is the Assistant Professor at Iran University of Science and Engineering since 2016. She has compelted her PhD degree in Chemical Engineering (Petroleum) from Amirkabir University of Technology in 2013. Her research fields include reservoir simulation, well testing, unstructured mesh generation algorithms, asphaltene precipitation and deposition, population balance and computational intelligence scheme. She has published a number of journal and conference articles in the field.
Steam assisted gravity drainage (SAGD) is one of the most practical methods in enhanced oil recovery processes for heavy oil reservoirs. Fast-SAGD is a modification for SAGD process in which OFFSET wells are drained alongside the SAGD well pair for cyclic production and injection. Offset wells are applied for increasing the steam chamber laterally which is cost effective in comparison to SAGD process. There is limited number of studies for Fast-SAGD process in comparison to other EOR processes. In previous studies, the effective parameters of Fast-SAGD process have been optimized manually and sensitivity analyses are done based on these results. The studied parameters include, paired wells of SAGD, the locus of offset wells, injection pressure, production rate, starting time for the injection through offset wells and production time for the offset wells. In the present study, all the stated parameters are optimized through reservoir simulation using genetic algorithm in a naturally fractured heavy oil reservoir in Iran. To do this, CMG-STARS software was coupled to MATLAB toolbox to optimize this process. Results showed that optimized conditions were achieved for the locus of the wells using this technique which lead to more ultimate recovery factor (RF) for 5 to 15% in various conditions. The amount of the injected gas was also reduced significantly in comparison to previous studies which lead to lower economic cost and higher income.