scholarly journals Log based petrophysical analysis of mio-pliocene sandstone reservoir encountered in well Rashidpur 4 of Bengal Basin in Bangladesh

2016 ◽  
Vol 51 (1) ◽  
pp. 23-34
Author(s):  
M Farhaduzzaman ◽  
MA Islam ◽  
WH Abdullah ◽  
J Dutta
Keyword(s):  
Gamma Ray ◽  
Water Saturation ◽  
Xrd Analysis ◽  
Bengal Basin ◽  
Petrophysical Parameters ◽  
Shale Volume ◽  
Quantitative Measurements ◽  
Volume Porosity ◽  
Bulk Volume ◽  
Hydrocarbon Saturation

Rashidpur is located in the northeastern part of Bangladesh which is surrounded on three sides by India and on a small portion by Myanmar. Gamma-ray, spontaneous potential, density, neutron, resistivity, caliper, temperature and sonic logs are used to analyze petrophysical parameters of the well Rashidpur 4, Bangladesh. Quantitative measurements of different factors such as shale volume, porosity, permeability, water saturation, hydrocarbon saturation and bulk volume of water are carried out using well logs. Petrographic and XRD results based on several core samples are also compared with log-derived parameters. Twenty permeable zones are identified whereby four are hydrocarbon bearing in the studied Mio-Pliocene reservoir sandstones. Measured shale volume ranges from 11% to 38% and porosity is 19% to 28%. However, log-derived porosity is slightly higher than the thin section porosity. Water saturation of the interested zones varies from 14% to 38%, 13% to 39% and 16% to 41% measured from Schlumberger, Fertl and Simandoux formula respectively. Conversely, hydrocarbon saturation of the examined hydrocarbon zones ranges from 62% to 86%, 61% to 83% and 59% to 84% respectively. In the analyzed zones, the permeability values are calculated as 28-305 mD. Good to very good quality hydrocarbon reservoirs are appraised for the studied four zones based on the petrophysical parameters, petrographic observation and XRD analysis. Among these, Zone 4 is the best quality reservoir for hydrocarbon.Bangladesh J. Sci. Ind. Res. 51(1), 23-34, 2016

Evaluation of Reservoir’s Petrophysical Parameters, Niger Delta, Nigeria

2017 ◽  
Vol 5 (1) ◽  
pp. 19
Author(s):  
Ubong Essien ◽  
Akaninyene Akankpo ◽  
Okechukwu Agbasi
Keyword(s):  
Niger Delta ◽  
Gamma Ray ◽  
Water Saturation ◽  
Petrophysical Parameters ◽  
Niger Delta Region ◽  
Average Porosity ◽  
Irreducible Water Saturation ◽  
Open Hole ◽  
Bulk Volume ◽  
Niger Delta Basin

Petrophysical analysis was performed in two wells in the Niger Delta Region, Nigeria. This study is aimed at making available petrophysical data, basically water saturation calculation using cementation values of 2.0 for the reservoir formations of two wells in the Niger delta basin. A suite of geophysical open hole logs namely Gamma ray; Resistivity, Sonic, Caliper and Density were used to determine petrophysical parameters. The parameters determined are; volume of shale, porosity, water saturation, irreducible water saturation and bulk volume of water. The thickness of the reservoir varies between 127ft and 1620ft. Average porosity values vary between 0.061 and 0.600; generally decreasing with depth. The mean average computed values for the Petrophysical parameters for the reservoirs are: Bulk Volume of Water, 0.070 to 0.175; Apparent Water Resistivity, 0.239 to 7.969; Water Saturation, 0.229 to 0.749; Irreducible Water Saturation, 0.229 to 0.882 and Volume of Shale, 0.045 to 0.355. The findings will also enhance the proper characterization of the reservoir sands.

scholarly journals Prospect evaluation and hydrocarbon potential assessment: the Lower Eocene Facha non-clastic reservoirs, Hakim Oil Field (NC74A), Sirte basin, Libya—a case study

2019 ◽  
Vol 10 (2) ◽  
pp. 351-362 ◽  
Author(s):  
Mohamed A. Kassab ◽  
Ali El-Said Abbas ◽  
Mostafa A. Teama ◽  
Musa A. S. Khalifa
Keyword(s):  
Gamma Ray ◽  
Water Saturation ◽  
Oil Field ◽  
Thickness Variation ◽  
Oil Accumulation ◽  
Lower Eocene ◽  
Log Data ◽  
Shale Volume ◽  
Volume Porosity ◽  
Sirte Basin

Abstract Petrophysical assessment of Facha Formation based on log data of six wells A1, A3, A4, A5, A8 and A13 recorded over the entire reservoir interval was established. Hakim Oil Field produces from the Lower Eocene Facha reservoir, which is located at the western side of Sirte basin. Limestone, dolostone and dolomitic limestone are the main lithologies of the Facha reservoir. This lithology is defined by neutron porosity—density cross-plot. Noteworthily, limestone increases in the lowermost intervals of the reservoir. Structurally, the field is traversed by three northwest–southeast faults. The shale of the Upper Cretaceous Sirte Formation is thought to be the source rock of the Facha Formation, whereas the seals are the limestone and anhydrite of the Lower Eocene Gir Formation. In this study, the Facha reservoir’s cutoff values were obtained from the cross-plots of the calculated shale volume, porosity and water saturation values accompanied with gamma ray log data and were set as 20%, 10% and 70%, respectively. Isoparametric maps for the thickness variation of net pay, average porosity, shale volume and water saturation were prepared, and the authors found out that the Facha Formation has promising reservoir characteristics in the area of study; a prospective region for oil accumulation trends is in the north and south of the study area.

scholarly journals Re-evaluation of Petro physical Properties in Yammama Formation at Nasiriya Field

2019 ◽  
Vol 20 (3) ◽  
pp. 59-66
Author(s):  
Karrar Hayder Jassim ◽  
Jalal A. Al-Sudani
Keyword(s):  
Physical Properties ◽  
Gamma Ray ◽  
Water Saturation ◽  
Uranium Content ◽  
Geological Model ◽  
North West ◽  
Shale Volume ◽  
The North ◽  
Volume Porosity ◽  
Gamma Ray Log

Nasiriya field is located about 38 Km to the north – west of Nasiriya city. Yammama, a giant lower cretaceous reservoir in Nasiriya field which is lithologically formed from limestone. Yammama mainly was divided into three main reservoir units YA, YB1, YB2 and YB3 and it is separated by impermeable layers of variable thickness. An accurate petro physical evolution of the reservoir is of great importance perform an excellent geological model so that four petro physical properties which are shale volume, porosity, water saturation and permeability was re-evaluated. The volume of shale was calculated using the density and neutron logs (VSH-DN) rather than using gamma ray log because of presence a uranium content in the formation that makes overestimation of shale volume. Cross plots of Density Neutron logs are used to determine porosity by using IP software, which is correcting automatically Density Neutron logs for the effect of shale. Indonesian equation was used to estimate water saturation for five wells rather than Archie equation in order to consider shale volume. Fuzzy logic was adopted to predict permeability instead of regression analysis (cross plot) because of presence of errors in the results in this method. The results are shown that units YB2 and YB3 have best reservoir quality.

scholarly journals DETERMINING OF FORMATION WATER SATURATION TO ESTIMATE REMINING HYDROCARBON SATURATION IN THE X LAYER Y FIELD

PETRO ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 119
Author(s):  
Ratnayu Sitaresmi ◽  
Guntur Herlambang Wijanarko ◽  
Puri Wijayanti ◽  
Danaparamita Kusumawardhani
Keyword(s):  
Gamma Ray ◽  
Water Saturation ◽  
Effective Porosity ◽  
Reservoir Rock ◽  
Formation Water ◽  
Core Data ◽  
Shale Volume ◽  
Average Water ◽  
Hydrocarbon Saturation ◽  
Exploratory Wells

<p>Efforts are made to find the remaining hydrocarbons in the reservoir, requiring several methods to calculate the parameters of reservoir rock characteristics. For this reason, logging and core data are required. The purpose of this research is to estimate the Remaining Hydrocarbon Saturation that can be obtained from log data and core data. With several methods used, can determine petrophysical parameters such as rock resistivity, shale volume, effective porosity, formation water resistivity, mudfiltrate resistivity and rock resistivity in the flushed zone (Rxo) and rock resistivity in the Uninvaded Zone which will then be used to calculate the Water Saturation value Formation (Sw) and Mudfiltrat Saturation. (Sxo) In this study four exploratory wells were analyzed. Shale volume is calculated using data from Gamma Ray Log while effective Porosity is corrected for shale volume. Rw value obtained from the Pickett Plot Method is 0.5 μm. The average water saturation by Simandoux Method were 33.6%, 43.4%, 67.0% and 39.7% respectively in GW-1, GW-2, GW-3 and GW-4 wells. While the average water saturation value by the Indonesian Method were 43.9%, 48.8%, 72.3% and 44% respectively in GW-1, GW-2, GW-3 and GW-4 wells. From comparison with Sw Core, the Simandoux Method looks more appropriate. Average mudfiltrate (Sxo) saturation by Simandoux Method were 65.5%, 68.2%, 77.0% and 64.6% respectively in GW-1, GW-2, GW-3 and GW wells -4. Remaining Hydrocarbon Saturation (Shr) was obtained by 34.5%, 31.8, 23%, 35.4% of the results of parameters measured in the flushed zone namely Rxo, Rmf and Sxo data. For the price of Moving Hydrocarbons Saturation or production (Shm) is 31.9%, 24.8%, 10%, 24.9% in wells GW-1, GW-2, GW-3 and GW-4.</p>

scholarly journals Geophysical and hydrocarbon prospect evaluation of Nukhul Formation at Rabeh East oil field, Southern Gulf of Suez Basin, Egypt

2021 ◽  
Vol 11 (7) ◽  
pp. 2877-2890
Author(s):  
Mohammad Abdelfattah Sarhan
Keyword(s):  
Water Saturation ◽  
Total Porosity ◽  
Effective Porosity ◽  
Oil Field ◽  
Normal Faults ◽  
Gulf Of Suez ◽  
Petrophysical Parameters ◽  
Shale Volume ◽  
Bulk Volume ◽  
Zone Ii

AbstractNukhul Formation is one of the primary oil reservoirs in the Gulf of Suez Basin. Rabeh East is an oil producer field located at the southern border of the Gulf of Suez. The present work deals with the geophysical investigation of Nukhul Formation in Rabeh East field using seismic lines and well log data of four wells, namely RE-8, RE-22, RE-25 and Nageh-1. The interpreted seismic profiles display that the RE-8 Well is the only well drilled within the up-thrown side of a significant horst fault block bounded by two normal faults. However, the other wells penetrated the downthrown side. The qualitative interpretation of the well logging data for RE-8 Well delineated two intervals have good petrophysical parameters and ability to store and produce oil. These zones locate between depths 5411.5 and 5424 ft (zone I) and between 5451 and 5459.5 ft (zone II). The calculated petrophysical parameters for zone I display water saturation (22–44%), shale volume (10–23%), total porosity (18–23%), effective porosity (12–20%) and bulk volume of water (0.04–0.06). Zone II exhibits water saturation (13–45%), shale volume (10–30%), total porosity (18–24%), effective porosity (11–20%) and bulk volume of water (0.03–0.05). This analysis reflects excellent petrophysical characteristics for the sandstones of Nukhul Formation in Rabeh East oil field for producing oil if the wells drilled in a suitable structural closure.

scholarly journals Petrophysical Properties of Nahr Umar Formation in Nasiriya Oil Field

2020 ◽  
Vol 21 (3) ◽  
pp. 9-18
Author(s):  
Ahmed Abdulwahhab Suhail ◽  
Mohammed H. Hafiz ◽  
Fadhil S. Kadhim
Keyword(s):  
Gamma Ray ◽  
Water Saturation ◽  
Oil Field ◽  
Well Logs ◽  
High Porosity ◽  
Reservoir Properties ◽  
Petrophysical Parameters ◽  
Resistivity Logs ◽  
Lithology Prediction ◽  
Porosity And Permeability

   Petrophysical characterization is the most important stage in reservoir management. The main purpose of this study is to evaluate reservoir properties and lithological identification of Nahr Umar Formation in Nasiriya oil field. The available well logs are (sonic, density, neutron, gamma-ray, SP, and resistivity logs). The petrophysical parameters such as the volume of clay, porosity, permeability, water saturation, were computed and interpreted using IP4.4 software. The lithology prediction of Nahr Umar formation was carried out by sonic -density cross plot technique. Nahr Umar Formation was divided into five units based on well logs interpretation and petrophysical Analysis: Nu-1 to Nu-5. The formation lithology is mainly composed of sandstone interlaminated with shale according to the interpretation of density, sonic, and gamma-ray logs. Interpretation of formation lithology and petrophysical parameters shows that Nu-1 is characterized by low shale content with high porosity and low water saturation whereas Nu-2 and Nu-4 consist mainly of high laminated shale with low porosity and permeability. Nu-3 is high porosity and water saturation and Nu-5 consists mainly of limestone layer that represents the water zone.

scholarly journals Shale volume and permeability of the Miocene unconsolidated turbidite sands of Bonga oil field, Niger delta, Nigeria

2017 ◽  
Vol 5 (1) ◽  
pp. 37 ◽  
Author(s):  
Inyang Namdie ◽  
Idara Akpabio ◽  
Agbasi Okechukwu .E.
Keyword(s):  
Niger Delta ◽  
Gamma Ray ◽  
Water Saturation ◽  
Strong Dependence ◽  
Water Injection ◽  
Oil Field ◽  
Reservoir Properties ◽  
Injection Wells ◽  
Log Data ◽  
Shale Volume

Bonga oil field is located 120km (75mi) southeast of the Niger Delta, Nigeria. It is a subsea type development located about 3500ft water depth and has produced over 330 mmstb of hydrocarbon till date with over 16 oil producing and water injection wells. The producing formation is the Middle to Late Miocene unconsolidated turbidite sandstones with lateral and vertical homogeneities in reservoir properties. This work, analysis the petrophysical properties of the reservoir units for the purpose of modeling the effect of shale content on permeability in the reservoir. Turbidite sandstones are identified by gamma-ray log signatures as intervals with 26-50 API, while sonic, neutron, resistivity, caliper and other log data are applied to estimate volume of shale ranging between 0.972 v/v for shale intervals and 0.0549 v/v for turbidite sands, water saturation of 0.34 v/v average in most sand intervals, porosity range from 0.010 for shale intervals to 0.49 v/v for clean sands and permeability values for the send interval 11.46 to2634mD, for intervals between 7100 to 9100 ft., Data were analyzed using the Interactive Petrophysical software that splits the whole curve into sand and shale zones and estimates among other petrophysical parameters the shale contents of the prospective zones. While Seismic data revealed reservoir thickness ranging from 25ft to over 140ft well log data within the five wells have identified sands of similar thickness and estimated average permeability of700mD. Within the sand units across the five wells, cross plots of estimated porosity, volume of shale and permeability values reveal strong dependence of permeability on shale volume and a general decrease in permeability in intervals with shale volume. It is concluded that sand units with high shale contents that are from0.500 to0.900v/v will not provide good quality reservoir in the field.

scholarly journals Geophysical appraisal for the sandy levels within Abu Roash C and E members in Abu Gharadig Field, Western Desert, Egypt

2021 ◽  
Vol 11 (3) ◽  
pp. 1101-1122
Author(s):  
Mohammad Abdelfattah Sarhan
Keyword(s):  
Relative Permeability ◽  
Water Saturation ◽  
Effective Porosity ◽  
Western Desert ◽  
Absolute Permeability ◽  
Normal Faults ◽  
Shale Volume ◽  
Bulk Volume ◽  
Zone Ii ◽  
Water Cut

AbstractThe present work concerns with the geophysical assessment for the sandstones of Abu Roash C and E members for being potential hydrocarbon reservoirs at Abu Gharadig Field, Western Desert, Egypt. The analysis of seismic data covers Abu Gharadig Field showing ENE–WSW anticline fragmented by NW–SE normal faults. The presence of these structures is due to the dextral wrench corridor that extensively deformed the north area of the Western Desert within Late Cretaceous episode. The examination of well-log data of Abu Gharadig-6 Well revealed that the favourable zone locates between depths 9665–9700 ft (zone I) within Abu Roash “C” Member. The second promising zone in Abu Gharadig-15 Well occurs between depths 9962–9973 ft (zone II) in Abu Roash “E” Member. The quantitative evaluation indicated that zone I has better reservoir quality than zone II since it is characterised by low shale volume (0.01), high effective porosity (0.22), low water saturation (0.14), low bulk volume of water (0.03), higher values of absolute permeability (113 mD), high relative permeability to oil and low water cut, whereas zone II has 0.13 shale volume, 0.16 effective porosity, 0.39 water saturation, 0.06 bulk volume of water, lower values of absolute permeability (27 mD), low relative permeability to oil and relatively high water cut. The obtained results recommended that the drilling efforts should be focused on the sandy levels within Abu Roash C Member (1st priority) and the sand levels within Abu Roash E Member (2nd priority) in Abu Gharadig Basin and its surroundings.

scholarly journals Determination of Petrophysical Parameters of Reservoir Rock with a Special Look to Shale Effect (Case Study: One of the Gas Fields in Southern Iran)

2021 ◽  
Vol 5 (2) ◽  
pp. 1-10
Author(s):  
Taheri K
Keyword(s):  
Water Saturation ◽  
Accurate Determination ◽  
Reservoir Rock ◽  
Petrophysical Properties ◽  
Gas Reservoir ◽  
Reservoir Water ◽  
Petrophysical Parameters ◽  
Hydrocarbon Reservoir ◽  
Shale Volume

Determination of petrophysical parameters is necessary for modeling hydrocarbon reservoir rock. The petrophysical properties of rocks influenced mainly by the presence of clay in sedimentary environments. Accurate determination of reservoir quality and other petrophysical parameters such as porosity, type, and distribution of reservoir fluid, and lithology are based on evaluation and determination of shale volume. If the effect of shale volume in the formation not calculated and considered, it will have an apparent impact on the results of calculating the porosity and saturation of the reservoir water. This study performed due to the importance of shale in petrophysical calculations of this gas reservoir. The shale volume and its effect on determining the petrophysical properties and ignoring it studied in gas well P19. This evaluation was performed in Formations A and B at depths of 3363.77 to 3738.98 m with a thickness of 375 m using a probabilistic calculation method. The results of evaluations of this well without considering shale showed that the total porosity was 0.1 percent, the complete water saturation was 31 percent, and the active water saturation was 29 percent, which led to a 1 percent increase in effective porosity. The difference between water saturation values in Archie and Indonesia methods and 3.3 percent shale volume in the zones show that despite the low shale volume in Formations A and B, its effect on petrophysical parameters has been significant. The results showed that if the shale effect not seen in the evaluation of this gas reservoir, it can lead to significant errors in calculations and correct determination of petrophysical parameters.

scholarly journals Evaluation of Petrophysical Parameters of Reservoir Sand Wells in Uzot-Field, Onshore Niger Delta Basin, Nigeria

2021 ◽  
Vol 25 (2) ◽  
pp. 157-171
Author(s):  
UC Omoja ◽  
T.N. Obiekezie
Keyword(s):  
Niger Delta ◽  
Gamma Ray ◽  
Depth Range ◽  
High Hydrocarbon ◽  
Hydrocarbon Production ◽  
Petrophysical Parameters ◽  
Resistivity Logs ◽  
Hydrocarbon Saturation ◽  
Niger Delta Basin ◽  
Sand Bodies

Evaluation of the petrophysical parameters in Uzot-field was carried out using Well log data. The target for this study was the D3100 reservoir sand of wells Uz 004, Uz 005, U008 and Uz 011 with depth range of 5540ft to 5800ft across the four wells. Resistivity logs were used to identify hydrocarbon or water-bearing zones and hence indicate permeable zones while the various sand bodies were then identified using the gamma ray logs. The results showed the delineated reservoir units having porosity ranging from 21.40% to 33.80% indicating a suitable reservoir quality; permeability values from 1314md to 18089md attributed to the well sorted nature of the sands and hydrocarbon saturation range from 12.00% to 85.79% implying high hydrocarbon production. These results suggest a reservoir system whose performance is considered satisfactory for hydrocarbon production. Keywords: Petrophysical parameters, porosity, permeability, hydrocarbon saturation, Niger Delta Basin

Sign in / Sign up

Export Citation Format

Share Document