Hydrocarbon Type Estimation Using the Synthetic Logs: A Case Study in Baba Member, Gulf of Suez, Egypt
Lack of pressure data and/or one curve of the essential well logs such as density, neutron, sonic, resistivity and gamma ray curves in some reservoirs, is not preferred situation for the petrophysict, which this will affect the petrophysical evaluation process and the reservoir characterization study. Four wells (A, B, C and D) in the area of interest penetrated Baba sandstone (S.S.) zone in Badri field, the main challenge in the studied zone is the absence of pressure gradients and the density-neutron separation is not clear enough to judge the hydrocarbon type in all wells at the level of baba (S.S.) reservoir, where they are needed for the estimation of the hydrocarbon type (oil or gas) in the untested area of interest using the available data, so it is preferred to use the three porosity logs to investigate the hydrocarbon type. The second challenge is using the synthetic logs in the absence of the used three porosity logs. In this paper, all available data were used to estimate the hyocarbon type in two studied wells at the level of Baba (S.S.) zone, firstly by using well logging relations between density and sonic in the wells which have sonic logs at the zone of interest, secondly by applying special petrophysical studies to help for estimation of hydrocarbon type. Crossplot technique was used to estimate the hydrocarbon type in the zone of interest using the synthetic sonic curve, original density curve, original neutron curve plus their derived porosity and variables values such as (M, N, DTMAA and RHOMAA) in the used well logging Crossplots. These include (M-N and MID) Crossplots, which can help in this situation. The results of this study revealed that firstly the synthetic logs play a great role in solving of petrophysical and geological problems, secondly there was a good relation between the density and the sonic logs in the analogues (A and D) wells which have a complete set of logs, thirdly the obtained synthetic sonic log from the derived empirical equations makes a sense with lithology and other logs (neutron and gamma) and it is recommended to be used in Badri field for the zone of interest level, fourthly, the synthetic sonic log, in corporation with the density and the neutron logs with the crossplots can help for estimation of fluid type of the studied wells. The final result that the most likely hydrocarbon type in well (B) is an oil zone while it is a gas zone signature in well (C).
AAPG Datapages/Search and Discovery Article #90332 © 2018 AAPG International Conference and Exhibition, Cape Town, South Africa, November 4-11, 2018