scholarly journals Foraminiferal biostratigrpahy of oshi-13 field, coastal and central swamp depobelt, Niger delta basin, Nigeria

2018 ◽  
Vol 6 (1) ◽  
pp. 127
Author(s):  
J R. Nimnu ◽  
G O Aigbadon ◽  
F Ogbikaya

A high resolution Foraminiferal biostratigrpahic study has been carried out using data from three wells located in the Coastal and Central Swamp depobelts of Niger Delta.The study defined six (N6-N15) Foraminiferal zones for the early to middle Miocene Niger Delta on the basis of index Foraminiferal and this was correlated to Blow, 1969 and Bergreen et al., 1995. Foraminiferal analysis shows that Oshi-13Field is very rich in calcareous and araneceous benthics, calcareous and planktic foraminiferal. The abudance of fossils and index fossils are responsible for constructing the biostratigraphic chart and hydrocarbon saturation in the field. The biostratigraphy chart constructed act as a basis in establishing the ages of sediments/ sequence in the  studied field.   

2021 ◽  
Vol 25 (2) ◽  
pp. 157-171
Author(s):  
UC Omoja ◽  
T.N. Obiekezie

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


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
M. E. Nton ◽  
S. O. Famori

Abstract A high-resolution biostratigraphic study of the STEP-1 well, offshore Western Niger Delta Basin, Nigeria, was carried out using foraminifera, calcareous nannofossils and palynomorphs. The study was aimed at identifying the biostratigraphic zones, age deductions as well as palaeoenvironmental and palaeoclimatic reconstructions. From the studied well section of 609 m (1,829–2,438 m), 50 ditch cuttings were used for foraminifera and calcareous nannofossils, while 25 samples were used for palynological studies at 12 m and 24 m intervals, respectively. Standard laboratory preparation techniques were employed for the three microfossil groups. Due to the occurrence of some forms such as Globigerina praebulloides, Haplophragmoides spp, Bolivina scalprata miocenica, Valvulina flexilis and Cyclammina cf. minima, two planktonic and one benthonic foraminifera zones were identified as follows: Lower N18, Upper N17 zone (early Pliocene, late Pliocene) and Cyclammina minima zone (late Miocene), respectively. Two biozones were recognized for the nannofossils and include NN12 (Ceratolithus cristatus zone) and NN11 (Discoaster berggrenii zone). These zones were assigned to early Pliocene and late Miocene, respectively. Other forms include Discoaster pentaradiatus, Sphenolithus abies and Ceratolithus armatus. Echitricolporites spinosus/P800zone has been assigned for the Palynomorph assemblages and was dated late Miocene due to the quantitative occurrence of Cyperaceaepollis spp. Four identified major condensed sections include intervals at 1,926, 1,987, 2,097 and 2,316 m, which have been dated 5.0, 5.8, 6.3 and 7.0 Ma, respectively. Based on the benthonic foraminiferal species and Palynological Marine Index, a shallow marine environment is deduced for the studied interval which was interpreted to be deposited under both wet and dry palaeoclimatic conditions. The findings, no doubt could serve as a template for a sequence stratigraphic model, generally beyond the resolution of seismic stratigraphy.


2021 ◽  
Vol 13 (2) ◽  
pp. 601-610
Author(s):  
K. Itiowe ◽  
R. Oghonyon ◽  
B. K. Kurah

The sediment of #3 Well of the Greater Ughelli Depobelt are represented by sand and shale intercalation. In this study, lithofacies analysis and X-ray diffraction technique were used to characterize the sediments from the well. The lithofacies analysis was based on the physical properties of the sediments encountered from the ditch cuttings.  Five lithofacies types of mainly sandstone, clayey sandstone, shaly sandstone, sandy shale and shale and 53 lithofacies zones were identified from 15 ft to 11295 ft. The result of the X-ray diffraction analysis identified that the following clay minerals – kaolinite, illite/muscovite, sepiolite, chlorite, calcite, dolomite; with kaolinite in greater percentage. The non-clay minerals include quartz, pyrite, anatase, gypsum, plagioclase, microcline, jarosite, barite and fluorite; with quartz having the highest percentage. Therefore, due to the high percentage of kaolinite in #3 well, the pore filing kaolinite may have more effect on the reservoir quality than illite/muscovite, chlorite and sepiolite. By considering the physical properties, homogenous and heterogeneous nature of the #3 Well, it would be concluded that #3 Well has some prospect for petroleum and gas exploration.


Author(s):  
Joseph Nanaoweikule Eradiri ◽  
Ehimare Erhire Odafen ◽  
Ikenna Christopher Okwara ◽  
Ayonma Wilfred Mode ◽  
Okwudiri Aloysius Anyiam ◽  
...  

Author(s):  
Dairo VA

Biostratigraphic studies of foraminifera were carried out on two exploratory wells drilled in the Eastern Niger Delta to establish the age, biozonation and paleoenvironment of the foraminifera present in the strata penetrated by the wells. A total of 80 ditch cutting samples retrieved at 60ft intervals from AX-1 and AX-2 Wells at the depth of 3,600ft to 6,000ft and 4,200ft to 6500ft. respectively were subjected to micropaleontological analysis which involves picking and identification of the foraminifera present. The resulting data were loaded into the Stratabug software and interpreted. The foraminifera recovered and identified from the two wells are made up of both benthic and planktic species. The marker species, whose stratigraphic range are well established were used to describe the biozonation and these includes Heterostegina sp, Catapsydrax stainforthi, Chiloguembelina victoriana, Orbulina universa/suturalis, Praeorbulina sicana,Buliminella subfusiformis, Nonion centrosulcatum, Catapsydrax dissimilis, Globigerinoides bisphericus and Globigerinoides sicanus. Four biozones of foraminifera made up of N8, N7-N8, N6-N7 and N5-N6 were recognised based on the zonation scheme of Grandstein; with their stratigraphic age ranging from early Miocene to middle Miocene. Furthermore, the environment of deposition prevailing in the Formations penetrated by the two wells are predominantly middle neritic with similarity in their ages as observed from the correlation of the biozones from the two wells


2017 ◽  
Vol 5 (1) ◽  
pp. 19
Author(s):  
Ubong Essien ◽  
Akaninyene Akankpo ◽  
Okechukwu Agbasi

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.


Sign in / Sign up

Export Citation Format

Share Document