This study deal with structural and stratigraphic analysis of the seismic reflection data for Hartha Formation at Nasiriyah field, the area of seismic data is about (1237) km2. Nasiriyah oil field is located in Dhi Qar Governorate, southern Iraq, and the oil field is located to the East of Euphrates River of about (38) km northwest of Nasiriyah city. which includes twenty-four (24) wells. In some wells there are oil evidences in Hartha Formation at Nasiriyah oil field, for this reason, Hartha Formation is studied.
Two reflectors are picked (top and bottom Hartha) they are defined by using synthetic seismograms in time domain for wells (Ns-1, and 3). Time and depth of Hartha Formation are drawn using velocity data of reflectors. The structural interpretation shows top and bottom of Hartha Formation. The Nasiriyah structure appeared as several regular enclosures shapes, their general trend northwest-southeast. The structure has three enclosures situated on five wells. The general dip towards the northeast. Variance seismic attributes technique are used; instantaneous frequency, instantaneous phase and chaos are done to verify and confirm this structural interpretation .
Two coral Rudist (mound) accumulations are determined and interpreted. In addition, flat spot phenomenon has been observed which is located in northeast of the well site Ns-4 which represents a Direct Hydrocarbon Indicator (DHI) that refers to the presence of hydrocarbons.
In this paper, we attempt to predict the depositional environments with associated lithofacies of the main reservoir of the late Cretaceous Mishrif carbonate Formation, depending on the analysis of the created seismic isopach map by integrating seismic and well data. The isopach map was created from a 3D-seismic reflection survey carried out at the Dujaila oil field in southeastern Iraq, which is of an area of 602.26 Km2, and integrated with the data of the two explored wells. Based on the interpretation of the seismic isopach map, the diagram of the 3D-depositional environment model of Mishrif Formation was constructed. It showed three distinguished depositional environments, which were graduated from a back reef lithofacies of a shallo
... Show More
(9)
(4)
This research includes structure interpretation of the Yamama Formation (Lower Cretaceous) and the Naokelekan Formation (Jurassic) using 2D seismic reflection data of the Tuba oil field region, Basrah, southern Iraq. The two reflectors (Yamama and Naokelekan) were defined and picked as peak and tough depending on the 2D seismic reflection interpretation process, based on the synthetic seismogram and well log data. In order to obtain structural settings, these horizons were followed over all the regions. Two-way travel-time maps, depth maps, and velocity maps have been produced for top Yamama and top Naokelekan formations. The study concluded that certain longitudinal enclosures reflect anticlines in the east and west of the study ar
... Show More
(1)
Five oil sample of Mashrif and Nahr Umr Formation for Amarah oil field,
southern Iraq, were taken and analyzed in Geo Mark laboratory in USA center in
order to determine the bulk properties of crude oils and carbon isotopes for these
samples in addition to determine biomarker parameters using Gas
Chromatography(GC), and Gas Chromatography Mass Spectrometry )GCMS
(analytical technique. According to these biomarker analyses of the two formation, it
is indicated that they are non-degraded, marine, non-waxy, derived from
carbonate source and deposition in anoxic marine environment. This study also
showed that the bulk properties (terpanes and steranes) of Amarah oil field are one
family, and the source rocks contai
The Hartha Formation is a major carbonate succession deposited during the Late Campanian period. The current study depends on four selected wells (EB 1, 2, 4 and 30) within the East Baghdad oil field to study electrofacies and petrophysical properties related to the reservoir characterization.
The Hartha Formation is divided into three electro-facies units using GR and SP logs in Petrel software. The upper unit of the Hartha Formation is composed mainly of limestone. The middle unit is composing of thick layers of shale. The lower unit is composed mainly of limestone with few shale layers. The three units are divided into three types of rocks in relation to the total porosity: 1. High-moderate active porosity rocks (type I)
... Show More
(2)
(1)
The study deals with 3D seismic reflection in the central Iraq within Merjan oil field which is located approximately (130 km) to the southwest Baghdad and south of Razaza. The 3D seismic survey was interpreted; the results showed that the oil is found within Hartha Formation as stratigraphic traps and with the absence of structural traps. The major normal faults picked are trending N-S direction. There are also minor faults observed using the instantaneous phase and frequency sections, they proved the presence of the faults and showed that the ending of the Safawi reflector toward the north and northeast to the south and southeast and near the western border of fault because of the facies change in the area. The reflector shows a struct
... Show MoreThis paper includes studying the microfacies evalution of Mauddud Formaion in
four wells(Rt-2, Rt-5, Rt17 and Rt-19). Seventy-seven(77) sampels were collected
of above mentioned wells. Based on fossil content of the samples under study, four
main microfacies were identified: packstone , wakestone , grainstone and lime
mudstone microfacies ,which deposited in shallow open marine and restricted
marine environments. Petrographic examination of thin section indicated that
diagenesis vary in intensity from one site to another, such as dissolution,
cementation, compaction, dolomitization and micritization, which led to the
improvement and deterioration of porosity. The dominant pore types are vuggy,
interparticle and
Petrophysical properties of Mishrif Formation at Amara oil field is determined
from interpretation of open log data of (Am-1, 2 ,3 ,4 ,5 ,6 ,7 ,8 ,9 ,10 ,11 ,12
and13) wells. These properties include the total, the effected and the secondary
porosity, as well as the moveable and the residual oil saturation in the invaded and
uninvaded zones. According to petrophysical properties it is possible to divided
Mishrif Formation which has thickness of a proximately 400 m, into seven main
reservoir units (MA, MB11, MB12, MB13, MB21, MC1, MC2) . MA is divided into
four secondary reservoir units , MB11 is divided into five secondary reservoir units ,
MB12 is divided into two secondary reservoir units , MB13 is divided into
(10)
(8)
Knowing the distribution of the mechanical rock properties and in-situ stresses for the field of interest is essential for many applications concerning reservoir geomechanics, including wellbore instability analysis, hydraulic fracturing, sand production, reservoir compaction, subsidence and water/gas injection throughout the filed life cycle. Determining the rock's mechanical properties is challenging because they cannot be directly measured at the borehole. The recovered carbonate core samples are limited and only provide discrete data for specific depths. This study focuses on creating a detailed 1D geomechanical model of the Mishrif reservoir in the Nasriyah oil field to identify the fault regime type for each unit in the format
... Show More
The petroleum system of Halfaya oil field shows that the hydrocarbon generation of these Formations such as Sha′uiba and Nahr Umr are immature and have generated few oil TR ≤ 50% which are neglected as compared to Formations below them which are very rich source rock. The Formations of Yamama, Ratawi and Sulaiy are mature with TR ≤ 100%. Other Formations such as Sargelu ,Najma,Zubair and Gotnia are with very high maturity with TR ≥ 100% and completely generated hydrocarbon and depleted after hydrocarbon are expelled and migrate to reservoir rock of structure traps and this study indicates that the major seals of Upper Jurassic are Gotnia and Allan Formations and of Middle Miocene is LowerFars fatha Formation.