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\def\makelabel##1{\upshape ##1}}% } {\end{list}\end{raggedright}} \newenvironment{specHead}[2]% {\vspace{20pt}\hrule\vspace{10pt}% \phantomsection\label{#1}\markright{#2}% \pdfbookmark[2]{#2}{#1}% \hspace{-0.75in}{\bfseries\fontsize{16pt}{18pt}\selectfont#2}% }{} \def\TheFullDate{2018-01-15 (revised: 15 January 2018)} \def\TheID{\makeatother } \def\TheDate{2018-01-15} \title{Prospect Maturition using Seismic and Offset Well Data: The Osemu-Niger Delta Case Study} \author{}\makeatletter \makeatletter \newcommand*{\cleartoleftpage}{% \clearpage \if@twoside \ifodd\c@page \hbox{}\newpage \if@twocolumn \hbox{}\newpage \fi \fi \fi } \makeatother \makeatletter \thispagestyle{empty} \markright{\@title}\markboth{\@title}{\@author} \renewcommand\small{\@setfontsize\small{9pt}{11pt}\abovedisplayskip 8.5\p@ plus3\p@ minus4\p@ \belowdisplayskip \abovedisplayskip \abovedisplayshortskip \z@ plus2\p@ \belowdisplayshortskip 4\p@ plus2\p@ minus2\p@ \def\@listi{\leftmargin\leftmargini \topsep 2\p@ plus1\p@ minus1\p@ \parsep 2\p@ plus\p@ minus\p@ \itemsep 1pt} } \makeatother \fvset{frame=single,numberblanklines=false,xleftmargin=5mm,xrightmargin=5mm} \fancyhf{} \setlength{\headheight}{14pt} \fancyhead[LE]{\bfseries\leftmark} \fancyhead[RO]{\bfseries\rightmark} \fancyfoot[RO]{} \fancyfoot[CO]{\thepage} \fancyfoot[LO]{\TheID} \fancyfoot[LE]{} \fancyfoot[CE]{\thepage} \fancyfoot[RE]{\TheID} \hypersetup{citebordercolor=0.75 0.75 0.75,linkbordercolor=0.75 0.75 0.75,urlbordercolor=0.75 0.75 0.75,bookmarksnumbered=true} \fancypagestyle{plain}{\fancyhead{}\renewcommand{\headrulewidth}{0pt}} \date{} \usepackage{authblk} \providecommand{\keywords}[1] { \footnotesize \textbf{\textit{Index terms---}} #1 } \usepackage{graphicx,xcolor} \definecolor{GJBlue}{HTML}{273B81} \definecolor{GJLightBlue}{HTML}{0A9DD9} \definecolor{GJMediumGrey}{HTML}{6D6E70} \definecolor{GJLightGrey}{HTML}{929497} \renewenvironment{abstract}{% \setlength{\parindent}{0pt}\raggedright \textcolor{GJMediumGrey}{\rule{\textwidth}{2pt}} \vskip16pt \textcolor{GJBlue}{\large\bfseries\abstractname\space} }{% \vskip8pt \textcolor{GJMediumGrey}{\rule{\textwidth}{2pt}} \vskip16pt } \usepackage[absolute,overlay]{textpos} \makeatother \usepackage{lineno} \linenumbers \begin{document} \author[1]{Isaac Aigbedion} \author[2]{Innocent Okogbue} \affil[1]{ Ambrose Alli University} \renewcommand\Authands{ and } \date{\small \em Received: 10 December 2017 Accepted: 4 January 2018 Published: 15 January 2018} \maketitle \begin{abstract} The AVO Fluid Inversion (AFI) technique to predict the probability of oil and gas occurrence in OML-X and quantify the uncertainties associated with the fluid prediction using Seismic sections and some well picks from nearby Ose Field. The seismic data interpretation of the Osemu prospect was based mainly on the picking of seven horizon layers (including the sea bottom). Four deeper horizons (C, D, E & F) were analysed for prospect generation and volumetric estimation. Results showed a major NW-SE trending growth fault controlled sedimentation and structural deformation in the study area. The seismic interpretation has identified two main prospects in the Osemu area. These are named Osemu-Main and Osemu-Upper. From the study two wells are recommended to be drilled on the structure. The two are expected to pierce all the four reservoirs considered in the volumetrics mid way between the crest and the flank. \end{abstract} \keywords{} \begin{textblock*}{18cm}(1cm,1cm) % {block width} (coords) \textcolor{GJBlue}{\LARGE Global Journals \LaTeX\ JournalKaleidoscope\texttrademark} \end{textblock*} \begin{textblock*}{18cm}(1.4cm,1.5cm) % {block width} (coords) \textcolor{GJBlue}{\footnotesize \\ Artificial Intelligence formulated this projection for compatibility purposes from the original article published at Global Journals. However, this technology is currently in beta. \emph{Therefore, kindly ignore odd layouts, missed formulae, text, tables, or figures.}} \end{textblock*} \let\tabcellsep& \section[{Introduction}]{Introduction}\par he Osemu anomaly is one of the three major structures identified in OML-X (approx. 725 Sq.km) in water depth ranging between 60 and 160 meters in the Niger Delta-Nigeria. The other prospects are the Osno and Ose in the north and east respectively. The latter have been drilled and are currently producing and providing the referenced logs and well information used for the Osemu prospect study.\par A recent acquisition of approximately 360 km 2 3D seismic data over the Osemu prospect and the subsequent delivery of the processed seismic data prompted the interpretation of the data.\par The seismic data interpretation of the Osemu prospect was based mainly on the picking of seven horizon layers (including the sea bottom). Four deeper horizons (C, D, E \& F) were analysed for prospect generation and volumetric estimation. All the four horizons are considered to lie within the prolific Agbada formation of the Niger Delta basin Integration of 3D seismic model with petrophysical data has been a beneficial endeavor in use in the petroleum industry for some years now (Adeoye and Enikauselu, 2009; \hyperref[b1]{Aigbedion and Iyayi, 2007;} {\ref Emujakporu and Faluyi, 2015)} in petroleum provinces where exploration and production strategies merge, detailed understanding of petrophysical properties is highly desired. Landmark's software and computer hardware located in-house were used in the interpretation of the seismic sections. The Geophysical data consisted of approximately 360 Km 2 of conventional 3D seismic and a depth model for the entire volume. The closest well with a check shot (Ose-5) is about 17km away from the prospect. The overall aim of this study is to use the AVO Fluid Inversion (AFI) technique to predict the probability of oil and gas occurrence in OML-X and quantify the uncertainties associated with the fluid prediction. \section[{II.}]{II.} \section[{Objectives of the Study}]{Objectives of the Study}\par The overall aim of this study is to determine whether drillable anomalies exist in the Osemu prospect. The specific objectives of the study are as follows:\par i. Identify and interpret the potential hydrocarbon bearing anomalies of interest in the study area ii. Mature the prospect anomalies into drillable targets iii. Compute the hydrocarbon in place. \section[{III.}]{III.} \section[{Location of Study}]{Location of Study}\par The Osemu prospect is located in the southern part of the Niger Delta within OML-X (Oil Mining Lease) approximately 80 kilometers from the coastline (Figure {\ref 1}). It is within the shallow offshore Niger delta. T Fig. {\ref 3}.1: Location Map of Osemu Field \section[{Geology of the Study Area}]{Geology of the Study Area}\par The Niger Delta is situated in the Gulf of Guinea (fig. {\ref 1}) and extends throughout the Niger Delta Province as defined by \hyperref[b6]{Klett et al (1997)}. From the Eocene to the present, the delta has prograded southwestward, forming depobelts that represent the most active portion of the Delta at each stage of its development \hyperref[b4]{(Doust and Omatsola, 1990}). These depobelts formone of the largest regressive deltas in the world with an area of some 300,000 km2 \hyperref[b7]{(Kulke, 1995)}, a sediment volume of 500,000 km3 (Hospers, 1965), and sediment thickness of over 10 km in the basin depocenter \hyperref[b5]{(Kaplan et al. 1994)}.\par Three geological formations are considered as part of the petroleum system in the Niger Delta. The basal one composed of marine shales, called the Akata Formation. This unit ranges in thickness from 600 m to more than 6000 m \hyperref[b8]{(Weber and Daukoru, 1975;} {\ref Aigbedion and Hafiz,2017)}. The overlaying formation is named Agbada. This formation consists of interbedded sands and shales and is known as the hydrocarbon bearing zone. The cap unit is the Benin Formation and comprises continental fluvial sands. This unit is a nonhydrocarbon bearing formation. Two structural patterns can be observed in the Osemu area from the fault orientations, and shape of the mapped levels The main structural controls are the arcuate NW-SE trending, synthetic growth faults. The Osemu area faults are subvertical with expressions at the seabed. This could be attributed to fault rejuvenation caused by tectonics of the underlying under-compacted massive Akata shales. Deformation takes place by gravitational gliding of rigid block along a decollment horizon above underlying shale as result of sedimentary loading (Figure {\ref 5}).\par Another remarkable feature in the Osemu geology is the pattern of termination of the NW-SE crystal faults which also corresponds to the point of bifurcation of the major fault into a bigger down dip component and a splinter at the up thrown. This arrangement suggests that the crystal collapse also initiated the extension of the major fault SE in a stress release mechanism. Subsequent sediment loading led to the SW rotation of the major fault to form an arcuate limb that supports the high zone of the Osemu closure (figure {\ref 15}) Lithostratigraphy: The Tertiary section of the Niger Delta is divided into three formations, representing prograding depositional facies that are distinguished mostly by the lithofacies mix. It is possible to summarise the stratigraphic column of the Niger Basin in three main diachronous lithologic formations; Benin, Agbada, and Akata (Figure {\ref 6}).\par Benin is the youngest formation and is comprised of continental, fluvio-alluvial and upper coastal plain sediments with good porosity, but generally low permeability, this fact limits to oil production from the Benin Formation in the Basin. The sequence passes laterally into the paralitic / deltaic sandstone of the Agbada Formation.\par The majority of hydrocarbons produced in the basin come from the alternating sandstone and siltstone that make up the Agbada Formation. A shelf to the deltaic/lagoonal environment characterized the sequence deposits. The observed small and largescale sedimentary cyclicity is probably mainly related to climatic change effects. Growth faults control/influence the sedimentation patterns. The paralic sandstone of Agbada Formation passes offshore into the distal prodelta\textbackslash deep marine shale of the Akata Formation.\par The Akata Formation at the base of the delta is of marine origin and is composed of thick shale sequences (potential source rock), turbidite sand (potential reservoirs in deep water), and minor amounts of clay and silt. Beginning in the Palaeocene and through the Recent, the Akata Formation formed during low stands when terrestrial organic matter and clays \section[{Osemu Area}]{Osemu Area} \section[{Main Structure Building (MSB) Fault}]{Main Structure Building (MSB) Fault}\par were transported to deep-water areas characterized by low energy conditions and oxygen. Turbidity currents likely deposited deep-sea fan sands within the upper Akata Formation during the development of the Delta. The Akata Formation (Eocene -Early Miocene) is dark grey marine shale throughout the basin and is typically considered to be the source rock for most of the hydrocarbon production in the area.\par Deposition of the three formations occurred in each of the five of flapping siliciclastic sedimentation cycles that make up the Niger Delta. These cycles (depobelts) are 30-60 kilometers wide, prograde southwestward 250 kilometers over oceanic crust into the Gulf of Guinea, and are defined by syn-sedimentary faulting that occurred in response to variable rates of subsidence and sediment supply. The interplay of subsidence and supply rates resulted in the deposition of discrete depobelts. When further crustal subsidence of the basin could no longer be accommodated, the focus of sediment deposition shifted seaward, forming a new depobelt. Each depobelt is a separate unit that corresponds to a break in the regional dip of the delta and is bounded landward by growth faults and seaward by large counter-regional faults or the growth fault of the next seaward belt. \section[{Materials and Methods}]{Materials and Methods} \section[{a) Materials}]{a) Materials}\par The Geophysical data consisted of approximately 360 Km 2 of conventional 3D seismic and a depth model for the entire volume. The closest well with a check shot (Ose-5) is about 17km away from the prospect. Since realistic check shot data was not available, it was necessary to use the RMS velocities provided by the processing company for conversion of the time generated maps to depth. The second order polynomial equation was used for the conversion.\par The geological data and the petro physical information referenced here were some well picks from nearby Ose field. \section[{AKATA Fm}]{AKATA Fm} \section[{Methodology}]{Methodology}\par The simplified workflow is as outlined below:\par ? An overview of the entire seismic volume was taken before deciding which reflectors should be mapped.\par Reference was also made to the depth at which hydrocarbon was found at nearby Ose and Osno fields.\par ? Horizons and faults were then mapped on crosslines and inlines. ? The mapped horizons were then exported along with their respective fault polygons to the mapping software. ? The time maps were then converted to depth by the RMS-Velocity equation for the seismic volume ( y=0.0001x²+0.9453x-97.214). \section[{a) Fault Picking}]{a) Fault Picking}\par The major NW-SE (Osemu F1) controlling fault was mapped across the area. The throw of fault decreases gradually towards the SE until it is truncated by a major arcuate, south dipping fault. \section[{b) Horizon Mapping}]{b) Horizon Mapping}\par A total of seven horizons were mapped. They represent the top of seismic sequences identified within a time zone of 1200 ms-2600ms. This is considered as the zone of interest by reference to the prospect levels in the adjacent Ose-Osno fields.\par Seven Horizons were mapped including the sea bed. Four Horizons are considered prolific (C, D, E \& F) due to their situation within the Agbada depth ranges. All Horizons were interpreted in time, then gridded and converted to depth. Figures {\ref (8, 10, 12, 14, 16, 18, \& 20)} shows Sea Bed, Horizons A, B, C, D, E \& F in time. Figure {\ref (9, 11, 13, 15, 17, 19 \& 21)} shows the respective horizons map in depth.\par The velocity model for the depth conversion was built into the respective time horizons to produce a depth equivalent using the RMS velocities (figure {\ref 2}). Volume XVIII Issue IV Version I c) Amplitude Extraction Amplitude extraction was done on all the mapped time horizons. Maximum Negative Amplitude maps were produced (figure {\ref 3a \& 3b}). The amplitudes did not show any hydrocarbon related anomalies as observed by their non-conformance to structure.\par The angle stacks were also examined for possible AVO effects. There was slight amplitude boost with offset. \section[{VII.}]{VII.} \section[{Discussion of Results}]{Discussion of Results} \section[{a) Prospects Identification o}]{a) Prospects Identification o}\par The seismic interpretation has identified two main prospects in the Osemu area. These are named Osemu-Main and Osemu-Upper. (Figure {\ref 6}.1) ? The Osemu-Main prospect is a tongue-like NW-SE trending formed at the downthrown block of the structure building fault. The structure is fault assisted at shallower levels (A-C) and faults dependent at depth. The areal extent of Osemu prospect is enhanced by the termination of the controlling fault against a south-dipping synthetic fault. The sealing capacity of the termination point impacts significantly on the prospectivity of the Osemu-Main. ? The Osemu-upper prospect is formed as a wedge between the bigger branch of the major fault and the northern splinter fault. \section[{b) Estimation of Hydrocarbon-In-Place}]{b) Estimation of Hydrocarbon-In-Place}\par The deterministic estimation of oil in place for the Osemu Field was completed using 3-D geological modeling in the Zmapp software package. This procedure involves bringing structural surfaces in from the geophysical package (Landmark), building a detailed fault model, and then modeling both facies distributions and the distribution of petrophysical parameters within the facies model {\ref (Deutsch and Hallstrom ,2000)}.\par Probable areas measured from depth maps for the prospective horizons ranges from 726 acres in Horizon E.0 to 3975 acres for Horizon C.0 (Table \hyperref[tab_1]{1}). Three cases were considered in determining the possible closure area. These are minimum, most likely and maximum contour closures representing varying sizes. \begin{figure}[htbp] \noindent\textbf{4}\includegraphics[]{image-2.png} \caption{\label{fig_0}Fig. 4 .}\end{figure} \begin{figure}[htbp] \noindent\textbf{41}\includegraphics[]{image-3.png} \caption{\label{fig_1}Fig. 4 . 1 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-4.png} \caption{\label{fig_2}Prospect}\end{figure} \begin{figure}[htbp] \noindent\textbf{42}\includegraphics[]{image-5.png} \caption{\label{fig_3}Fig. 4 . 2 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-6.png} \caption{\label{fig_4}}\end{figure} \begin{figure}[htbp] \noindent\textbf{50}\includegraphics[]{image-7.png} \caption{\label{fig_5}Fig 5 . 0 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{7891011131415}\includegraphics[]{image-8.png} \caption{\label{fig_6}Fig. 7 :Fig. 8 :Fig. 9 :Fig. 10 :Fig. 11 :Fig. 13 :Fig. 14 :Fig. 15 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{18192122}\includegraphics[]{image-9.png} \caption{\label{fig_7}FigFig. 18 :Fig. 19 :Fig. 21 :Fig. 22 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{23}\includegraphics[]{image-10.png} \caption{\label{fig_8}Fig. 23 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-11.png} \caption{\label{figure11}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-12.png} \caption{\label{figure12}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-13.png} \caption{\label{figure13}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-14.png} \caption{\label{figure14}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-15.png} \caption{\label{figure15}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-16.png} \caption{\label{figure16}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-17.png} \caption{\label{figure17}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-18.png} \caption{\label{figure18}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-19.png} \caption{\label{figure19}}\end{figure} \begin{figure}[htbp] \noindent\textbf{}\includegraphics[]{image-20.png} \caption{\label{figure20}}\end{figure} \begin{figure}[htbp] \noindent\textbf{} \par \begin{longtable}{P{0.39162303664921466\textwidth}P{0.23808900523560209\textwidth}P{0.20916230366492147\textwidth}P{0.01112565445026178\textwidth}} Late Extension\tabcellsep Extension\tabcellsep \multicolumn{2}{l}{Extension}\\ DISTAL REALM\tabcellsep CENTRAL REALM\tabcellsep \multicolumn{2}{l}{PROXIMAL REALM}\\ \tabcellsep Flank\tabcellsep \\ \tabcellsep (F) \&\tabcellsep \\ Counter\tabcellsep \tabcellsep \\ Regional\tabcellsep \tabcellsep Translation\\ (CRF)\tabcellsep \tabcellsep \\ \tabcellsep \tabcellsep Deep\tabcellsep Shale\\ Shale\tabcellsep \tabcellsep \\ Early\tabcellsep 3-10\tabcellsep \\ \multicolumn{2}{l}{Compression}\tabcellsep \\ Buried Toe Thrusts\tabcellsep Simple / Faulted Flank\tabcellsep Rollover or\\ Counter Regional Fault\tabcellsep Deep Rollover\tabcellsep \multicolumn{2}{l}{Collapsed Crest}\\ Early Phase\tabcellsep \tabcellsep \\ Toe Trusts\tabcellsep Simple Flank\tabcellsep \multicolumn{2}{l}{Simple Rollover}\\ \multicolumn{2}{l}{NO ACTIVE COUNTER REGIONAL FAULT}\tabcellsep \\ Reverse Footwall\tabcellsep Macrostructure Rollover\tabcellsep Simple Rollover\end{longtable} \par \caption{\label{tab_0}ACTIVE COUNTER REGIONAL FAULT Late Phase}\end{figure} \begin{figure}[htbp] \noindent\textbf{1} \par \begin{longtable}{P{0.85\textwidth}} The four (4) Horizons considered for volume\\ estimation (C, D, E \& F) have a total of 410.58mmbls as\\ P50, 309.32mmbls P10 and 445.21mmb is as P90.\end{longtable} \par \caption{\label{tab_1}Table 1 :}\end{figure} \begin{figure}[htbp] \noindent\textbf{} \par \begin{longtable}{P{0.15713815789473684\textwidth}P{0.057598684210526316\textwidth}P{0.03858552631578947\textwidth}P{0.2555592105263158\textwidth}P{0.02069078947368421\textwidth}P{0.13001644736842105\textwidth}P{0.035789473684210524\textwidth}P{0.06850328947368421\textwidth}P{0.052006578947368425\textwidth}P{0.012582236842105262\textwidth}P{0.02152960526315789\textwidth}} \multicolumn{3}{l}{SAND VALUE CONTOUR AREA CLOSURE ACRE}\tabcellsep \multicolumn{4}{l}{AVERAGE NET RK VOL. NET RK VOL. AVG-Ø AVG-Sw OHIP NET THICHNESS ACRE-FT MMBLS (\%) (\%) MMBLS}\tabcellsep FVF STOIP MMBLS\tabcellsep \multicolumn{3}{l}{REC FACTOR OIL-MMB MMBLS MMBLS U-RESV COM-PROD RR}\\ \tabcellsep MINIMUM (\tabcellsep -1780 1,322\tabcellsep 45.00 59,490.00\tabcellsep 461.52\tabcellsep 0.26\tabcellsep 0.25 90.00\tabcellsep 1.260 71.43\tabcellsep 0.30 21.43\tabcellsep 0\tabcellsep 21.43\\ \tabcellsep MOST LIKE\tabcellsep -1900 2,622\tabcellsep 45.00 117,990.00\tabcellsep 915.37\tabcellsep 0.28\tabcellsep 0.35 166.60\tabcellsep 1.260 132.22\tabcellsep 0.30 39.67\tabcellsep 0\tabcellsep 39.67\\ \tabcellsep MAXIMUM\tabcellsep -2000 3,975\tabcellsep 45.00 178,875.00\tabcellsep 1387.71\tabcellsep 0.24\tabcellsep 0.45 183.18\tabcellsep 1.260 145.38\tabcellsep 0.30 43.61\tabcellsep 0\tabcellsep 43.61\\ \tabcellsep MINIMUM (\tabcellsep -2200 1,655\tabcellsep 45.00 74,475.00\tabcellsep 577.78\tabcellsep 0.26\tabcellsep 0.25 112.67\tabcellsep 1.260 89.42\tabcellsep 0.30 26.83\tabcellsep 0\tabcellsep 26.83\\ \tabcellsep MOST LIKE\tabcellsep -2250 2,366\tabcellsep 45.00 106,470.00\tabcellsep 825.99\tabcellsep 0.28\tabcellsep 0.35 150.33\tabcellsep 1.260 119.31\tabcellsep 0.30 35.79\tabcellsep 0\tabcellsep 35.79\\ \tabcellsep MAXIMUM\tabcellsep -2300 3,480\tabcellsep 45.00 156,600.00\tabcellsep 1214.90\tabcellsep 0.24\tabcellsep 0.45 160.37\tabcellsep 1.260 127.28\tabcellsep 0.30 38.18\tabcellsep 0\tabcellsep 38.18\\ \tabcellsep MINIMUM (\tabcellsep -2500 726\tabcellsep 45.00 32,670.00\tabcellsep 253.45\tabcellsep 0.26\tabcellsep 0.25 49.42\tabcellsep 1.260 39.23\tabcellsep 0.30 11.77\tabcellsep 0\tabcellsep 11.77\\ \tabcellsep MOST LIKE\tabcellsep -2550 1,072\tabcellsep 45.00 48,240.00\tabcellsep 374.25\tabcellsep 0.28\tabcellsep 0.35 68.11\tabcellsep 1.260 54.06\tabcellsep 0.30 16.22\tabcellsep 0\tabcellsep 16.22\\ \tabcellsep MAXIMUM\tabcellsep -2650 2,583\tabcellsep 45.00 116,235.00\tabcellsep 901.75\tabcellsep 0.24\tabcellsep 0.45 119.03\tabcellsep 1.260 94.47\tabcellsep 0.30 28.34\tabcellsep 0\tabcellsep 28.34\\ \tabcellsep MINIMUM (\tabcellsep -3030 2,022\tabcellsep 45.00 90,990.00\tabcellsep 705.90\tabcellsep 0.26\tabcellsep 0.25 137.65\tabcellsep 1.260 109.25\tabcellsep 0.30 32.77\tabcellsep 0\tabcellsep 32.77\\ \tabcellsep MOST LIKE\tabcellsep -3040 2,082\tabcellsep 45.00 93,690.00\tabcellsep 726.85\tabcellsep 0.28\tabcellsep 0.35 132.29\tabcellsep 1.260 104.99\tabcellsep 0.30 31.50\tabcellsep 0\tabcellsep 31.50\\ \tabcellsep MAXIMUM\tabcellsep -3050 2,135\tabcellsep 45.00 96,075.00\tabcellsep 745.35\tabcellsep 0.24\tabcellsep 0.45 98.39\tabcellsep 1.260 78.08\tabcellsep 0.30 23.43\tabcellsep 0\tabcellsep 23.43\\ \tabcellsep \tabcellsep \tabcellsep \multicolumn{2}{l}{MINIMUM (P10)}\tabcellsep \tabcellsep \tabcellsep 309.32\tabcellsep 92.79\tabcellsep \tabcellsep 92.79\\ TOTAL\tabcellsep \tabcellsep \tabcellsep \multicolumn{2}{l}{MOST LIKELY (P50)}\tabcellsep \tabcellsep \tabcellsep 410.58\tabcellsep 123.17\tabcellsep \tabcellsep 123.17\\ \tabcellsep \tabcellsep \tabcellsep MAXIMUM\tabcellsep \tabcellsep \tabcellsep \tabcellsep 445.21\tabcellsep 133.56\tabcellsep \tabcellsep 133.56\\ S/N\tabcellsep \multicolumn{2}{l}{Parameter}\tabcellsep \multicolumn{2}{l}{Indication}\tabcellsep \tabcellsep \tabcellsep \multicolumn{4}{l}{Probability of Success Osemu-Main Osemu-Upper}\\ 1\tabcellsep \tabcellsep Trap\tabcellsep \multicolumn{4}{l}{Fault assisted. Major fault up to surface}\tabcellsep 0.5\tabcellsep \tabcellsep 0.5\\ 2\tabcellsep \tabcellsep Seal\tabcellsep \multicolumn{4}{l}{Top and lateral seal confirmed in Osno/Ose}\tabcellsep 0.5\tabcellsep \tabcellsep 0.5\\ 3\tabcellsep \multicolumn{2}{l}{Timing}\tabcellsep \multicolumn{4}{l}{Migration after syn-depositional, faulting}\tabcellsep 0.7\tabcellsep \tabcellsep 0.7\\ 4\tabcellsep \multicolumn{2}{l}{Closure}\tabcellsep \multicolumn{3}{l}{200-1000m structural relief.}\tabcellsep \tabcellsep 1\tabcellsep \tabcellsep 0.5\\ 5\tabcellsep \multicolumn{2}{l}{Reservoir}\tabcellsep \multicolumn{4}{l}{High quality sands (adjoining blocks of OPL}\tabcellsep 0.8\tabcellsep \tabcellsep 0.6\\ \tabcellsep \tabcellsep \tabcellsep \multicolumn{3}{l}{90, Osno\&Ose prolific.}\tabcellsep \tabcellsep \tabcellsep \tabcellsep \\ 6\tabcellsep \multicolumn{2}{l}{Porosity}\tabcellsep \multicolumn{4}{l}{Nearby field in the range of 19-35\%}\tabcellsep 1\tabcellsep \tabcellsep 0.8\\ 7\tabcellsep \multicolumn{2}{l}{Permeability}\tabcellsep \multicolumn{4}{l}{As in Osno-Ose production profile}\tabcellsep 1\tabcellsep \tabcellsep 1\\ 8\tabcellsep \multicolumn{2}{l}{Source}\tabcellsep \multicolumn{4}{l}{Thick Akata shales. Same for nearby discoveries}\tabcellsep 1\tabcellsep \tabcellsep 1\\ 9\tabcellsep \multicolumn{2}{l}{Maturation}\tabcellsep \multicolumn{4}{l}{Thick overburden. Targets Deeper than nearby Discoveries}\tabcellsep 1\tabcellsep \tabcellsep 1\\ 10\tabcellsep \multicolumn{2}{l}{Migration}\tabcellsep \multicolumn{4}{l}{Migration path through fault systems}\tabcellsep 1\tabcellsep \tabcellsep 1\\ 11\tabcellsep \multicolumn{2}{l}{Preservation}\tabcellsep \multicolumn{4}{l}{Unlikelihood of biodegradation due to fault}\tabcellsep 0.6\tabcellsep \tabcellsep 0.6\\ \tabcellsep \tabcellsep \tabcellsep \multicolumn{3}{l}{Extension to the surface.}\tabcellsep \tabcellsep \tabcellsep \tabcellsep \\ 12\tabcellsep \multicolumn{2}{l}{Hc Quality}\tabcellsep \multicolumn{4}{l}{Oil and solution gas as in Osno/Ose.}\tabcellsep 0.9\tabcellsep \tabcellsep 0.9\\ 13\tabcellsep \multicolumn{2}{l}{Recovery}\tabcellsep \multicolumn{3}{l}{Natural drive as in Osno/Ose}\tabcellsep \tabcellsep 1\tabcellsep \tabcellsep 1\\ \tabcellsep \tabcellsep \tabcellsep \multicolumn{3}{l}{Overall Probability of Success}\tabcellsep \tabcellsep 0.85\tabcellsep \tabcellsep 0.78\\ \multicolumn{5}{l}{VIII. Conclusion and Recommendations}\tabcellsep \multicolumn{6}{l}{5. A time-depth model to be created from check shot}\\ \multicolumn{5}{l}{1. A major NW-SE trending growth fault controlled sedimentation and structural deformation in the area. 2. Two wells are proposed to be drilled on the structure. The two are expected to pierce all the four}\tabcellsep \multicolumn{6}{l}{data on one of the exploratory wells and compare with the RMS velocity and update it accordingly. 6. All essential log suite must be run during the exploratory drilling stage to acquire accurate and precise petrophysical details.}\\ \multicolumn{5}{l}{sands considered in the volumetrics mid way}\tabcellsep \tabcellsep \tabcellsep \tabcellsep \tabcellsep \\ \multicolumn{5}{l}{between the crest and the flank. 3. Fault analysis is to be carried on the main structure building fault to ascertain its sealing ability. 4. The Osemu upper prospect should be explored if}\tabcellsep \multicolumn{6}{l}{1. Adeoye TO, Enikanselu P (2009). Reservoir Mapping and Volumetric analysis using Seismic and Well Data. Ocean J. App. Sci. 2(4):66 -67.}\\ \multicolumn{4}{l}{the Osemu main is successful.}\tabcellsep \tabcellsep \tabcellsep \tabcellsep \tabcellsep \tabcellsep \end{longtable} \par \caption{\label{tab_2}Table}\end{figure} \footnote{© 2018 Global Journals} \backmatter \begin{bibitemlist}{1} \bibitem[Kulke et al. ()]{b7}\label{b7} \textit{}, H Kulke , Nigeria , H Kulke . \textit{Regional Petroleum Geology of the World. Part II} 1995. p. . \bibitem[Aigbedion Isaac and Hafiz Abdullai ()]{b0}\label{b0} ‘Evaluation of Hydrocarbon Prospect of Fareed -Detail of the volumetrics is shown in the table below’. \textit{Environment and Earth Science International} Aigbedion Isaac and Hafiz Abdullai (ed.) 2454-7352. 2017. (7) . (Nigeria Journal of Geography) \bibitem[Emujakporue and Faluyi ()]{b2}\label{b2} ‘Evaluation of hydrocarbon volume in'TRH' Field, onshore Niger Delta’. 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