Here, we also consider basement rocks to include those of sedimentary origin with little or no matrix porosity north, 1990, such as the cambro. Challenges in identifying hydrocarbon potential in fractured. The lancaster fractured basement is classified as a type 1 naturally fractured reservoir nfr, as it contains little to no intergranular matrix porosity or. The nature of naturally fractured reservoirs tom bratton denver, colorado, usa. We present an analysis of the south sumatra suban gas field, developed mainly in fractured carbonate and crystalline basement, where active deformation has partitioned the reservoir into distinct structural and stress domains.
Jun 23, 2010 koreksi judul pel mungkin lebih tepat kalo fractured basement reservoir menurut info yang terpercaya, justru yang menjadi seal pada reservoir ini adalah batuan dasar yang terekahkan itu juga yang ketebalannya sekitar 200300an meter kalo ga salah ya makanya pengeboran dengan target ini, basement dibor mencapai 500an meter tapi fracture yang terbentuk itu terisi oleh. A detailed facies description is shown in figure 12b. Polymer injection as a possible eor method for a fractured granite basement reservoir in the cuu long basin, vietnam pet petro chem eng j polymer injection as a possible eor method for a fractured granite basement reservoir in the cuu long basin, vietnam pham duc thang1 and pham huy giao2 1production division, petro vietnam, vietnam. From experiment, expert has found that with various rock types, fractured porosity has a smaller value than matrix porosity. These fractures enhance the porosity in this fractured basement reservoir. Reservoirs are related to cavernous fracture porosity in deep basement zones, and to porous cavernous fracturing at more shallow levels. Fractures were identified from the outcrops, cores, image logs, and the petrophysical analysis. An overlooked play type with strong indications of significant potential from a global seismic database introduction fractured basement reservoirs are most commonly defined as metamorphic and igneous rocks unconformably overlain by a sedimentary sequence, where faulting has led to the creation of a natural. Pdf characterization of a fractured basement reservoir using high.
Recovery mechanisms and oil recovery from a tight, fractured basement reservoir, yemen authors nicolas legrand. Paper spe 80541 presented at the spe asia pacific oil and gas conference andexhibition, jakarta, 9. The challenge in oil and gas exploration has now shifted due to increasingly difficult to get back up economic value in a conventional reservoir. Fracture frequency is variable, up to 2040 per metre of core. The reservoir was discovered in 1986 and has a cumulative production of 180 mbbl. Fractured basement reservoirs characterization in central. Fractured basement reservoirs in central sumatera basin would be a future indonesian oil and gas development. It has many oil producing fields including the habban field with oil occurrences in fractured basement rocks. The momentum contrasts with past decades when fractured basement reservoirs were dismissed as too difficult or just plain non reservoir. This study presents a characterization of fractured basement reservoir by using statistical and fractal methods with outcrop data, seismic data, as well as fmi log data. Peristiwa penemuan basement fractured yang berlaku sebagai batuan reservoir dalam industri hidrokarbon. Characterization of a fractured basement reservoir using high. Fractured basement reservoir yang sedang belajar geologi.
The field is delimited by four wells, each of which has been the subject of drill stem testing resulting in oil to surface. Fractured basement reservoir identification using geophysical. The outcome of experimental and theoretical investigation to determine the critical production rate for single and multi fractured system, the capillary pressure effect. Type 1 tectonic fractured reservoir, ain zalah field aqrawi et al. Polymer injection as a possible eor method for a fractured. They include reservoirs with low hydrocarbon recovery.
The geophysical well logging have been always utilized for geological and stratigraphic determinations, for the measurement of the main physical characteristics in order to provide calibration parameters for the surface geophysical surveys and for a qualitative localization of fractured and. Oil has been produced from fractured basement reservoirs for decades. In some fields, these fractured reservoirs can be extremely productive, whilst. Available oil samples from the habban1 well, which has hydrocarbons at different zones of the fractured basement reservoir, were analyzed. Structural analysis of a fractured basement reservoir. The basement of the rona ridge is comprised of granitic rocks which have been dated at between 2.
Pdf fracturedbasement reservoir modeling using continuous. In the statistical method, fracture intensity and length have been calculated from various outcrop data. Fractured basement reservoir characterization for fracture distribution, porosity and permeability prediction marie lefranc. An analog outcrop model needs to be conducted as a first step toward predicting subsurface fracture system attributes. Transpressional wrench faulting in the late oligocene in this part of the field emplaced a block of brittle granitic rock on top of organic. Fractured basement reservoirs are naturally fractured and do not require additional fraccing. Challenges in identifying hydrocarbon potential in fractured basement in mumbai high field. Approximately 85% of hydrocarbon production in vietnam is from fractured basement rocks 15,16. A case study from the west of shetland finding petroleum.
These resulted in the formation of numerous horst andgraben structures and the development of fractured basement reservoirs in the southeast part of the ans. Basement hydrocarbon exploration overview of petroleum. Understanding of reservoir compartmentalization and its. The lancaster fractured basement is classified as a type 1 naturally fractured reservoir nfr, as it contains little to no intergranular matrix porosity or permeability and, as such, the reservoir behaviour is entirely dominated by the fracture network nelson 2001. Pdf integrated petrophysical interpretation of fractured. The field is presently under development, with several development well locations identified for drilling. Improving seismic image and impedance inversion of the texas panhandle fractured basement reservoir. Fracturedbasement reservoir modeling using continuous. Kantaatmaja formation evaluation society of malaysia fesm about the course this fiveday workshop introduces the principle of formation evaluation in fractured reservoir especially in petrophisic. Reserves estimation of fractured reservoirs petrowiki. Fractured basement reservoirs occur in more than 25 basins in over 30 countries. Hydrocarbon charge distributions in basement may be unusual especially if sealing horizons are present such as poorly fractured or highly mineralized layerseg the lancaster discovery west of shetland. A simplified schematic fracture basement reservoir modelled by hurricane energy showing. Fractured and weathered basement reservoirs search and.
Relationship between porosity and permeability on fractured. Fractured basement reservoir ilmiah july 12, 2010 posted by ibnu dwi bandono in geology time. Practical aspects of simulation of fractured reservoirs 08012003 2003, james r. The workshop will emphasizes of petrophysical evaluation and fractured reservoir. Challenges in identifying hydrocarbon potential in. Oil is stored within the fracture network rather than in pore space within the rock, as would be seen in most other reservoirs. Natural fracture propping and earthquakeinduced oil migration in fractured basement reservoirs holdsworth, r.
Best practices for exploration dqg production examples iurp usa, venezuela, and brazil tako koning1. Pdf the application of seismic attributes for reservoir. Understanding basement fracture architecture in padra field, south. Gilman, page 4 of 35 with all these issues, there may appear to. Explorationist are developing various drilling technology, optimizing conventional reserves and unconventional reserve in reservoirs. Pdf the challenge in oil and gas exploration has now shifted due to increasingly difficult to get back up economic value in a conventional. On fractured reservoir, total porosity is the sum of primary porosity and secondary porosity the value of porosity is equal with static definition of rock capacity or total void volume of rock. Tako koning introduction basement rocks are important oil and gas reservoirs in a number of basins in the world including. Fractured basement reservoir characterization in barmer basin. Therefore, fracture identification and characterization is of the upmost.
Figure 10 units model used to calculate fracture permeability in reservoir fracture. Basement fracture reservoir is a particular feature with watercut performances compared to other common reservoirs due to extremely high fracture permeability. Apr 04, 2014 the potential of fractured basement reservoirs is often overlooked by explorers, yet there are numerous examples of basement fields having been discovered and produced over the decades from around the world see fig. The pretertiary fractured basement forms important hydrocarbonbearing reservoirs in the vietnammalaysia offshore area, and is being produced from such reservoirs in vietnam where the authors have extensive working experiences for both clastics and. Potential composite aquifers are developed within the weathered overburden and fractured bedrock of these crystalline rocks, and are commonly referred to as basement, hard rock, bedrock or weathered fractured rock aquifers. The problem of water coning in fractured basement reservoirs has been addressed in this work. The associated fracture meshwork greatly enhances reservoir quality. Naturally fractured basement reservoirs aapg datapages. Pdf characterization of a fractured basement reservoir. Relationship between porosity and permeability in fractured basement reservoir. This fiveday workshop introduces the principle of formation evaluation in fractured reservoir especially in petrophisic. The average porosity of fractured reservoir is small, about 23% while the permeability is distributed in relatively wide range.
Characterization of fractured basement reservoir using. Reservoirs in the basement is one type of reservoir that begins to be seen and is of particular concern in oil and gas exploration because it has. Fractured basement in mature basin exploration search and. Hurricanes first exploration well at lancaster, 20521a4, was the first uk exploration well drilled specifically to evaluate basement as an exploration play trice 2014. Geo expro vietnam improved images of fractured basement. These difficulties are attributable to the heterogeneity of the reservoir formation, which causes substantial uncertainties in estimates of oilgasinplace ogip and in reserves estimates res. Naturally fractured reservoirs constitute a substantial percentage of remaining hydrocarbon resources. Structural analysis of a fractured basement reservoir, central yemen veeningen, resi. The lancaster fractured basement is classified as a type 1 naturally fractured reservoir nfr, as it contains little to no intergranular matrix porosity or permeability and, as such, the reservoir behaviour is entirely dominated by the fracture network. Definitions of naturally fractured reservoirs, after nelson 2001 type 1. Appraisal and development of fractured basement and palaeozoic reservoirs remains a significant challenge because of the generally high degree. Fractured basement reservoirs are most commonly defined as metamorphic and igneous rocks unconformably overlain by a sedimentary sequence, where faulting has led to the creation of a natural fracture network where hydrocarbons can accumulate. Basement reservoir specialists fractured basement wos. Fractured basement an overlooked play type with strong.
Basement exploration in india has seen increased interest after the recent discovery of a field in the cauvery basin in southeastern india, with an average individual well production of 700 bd from a fractured basement reservoir. The sabatayn basin is one of the most prolific mesozoic hydrocarbon basins located in central yemen. In fractured basement reservoirs, additional hydrocarbon potential can be found outside of structural closure as oil backfills down through the highly permeable fracture network, a highly attractive characteristic proven by hurricane energy. The fracture porosity in the rest of the basement reservoir is less than 5% and the lithology is mainly granite and quartzfeldspar. Hurricane continued this success with a sidetrack 20521a4z in 2010 to. Formation evaluation of fractured basement, cambay basin. In that regard, the brittleness of rocks is a function of the rock type, grain size, cementation, porosity, temperature and the effective confining pressure stearns, 1972. The optimum statistical distribution functions of fracture length for outcrops have been identified with the use of. Diffraction imaging is an alternative processing procedure. Fractured reservoirs pose formidable difficulties for estimating reserves. The data record microbial biodegradation of hydrocarbons in a fractured basement reservoir, and add to. Aguilera provides guidelines for estimating re in fractured reservoirs, classifying fractured reservoirs by pore type and storage ratiothe relative amount of storage in matrix vs. On the other hand, they represent some of the largest, most productive reservoirs on earth. Fractured basement reservoirs and oil displacement.
Fractured basement considerations basement is defined as the crystalline igneous or metamorphic rock underlying the sedimentary cover. Ray summary mumbai high field in the western offshore of india established the hydrocarbon accumulation in the basement rocks through exploratory drilling way back as early 80s. The kotopanjang area was chosen for this study because of good quality outcrops of pretertiary basement of the. Apr 08, 2019 first oil from the fractured basement in hurricanes lancaster field, located along the prominent rona ridge basement that is home to most of its portfolio, can now proceed this year after the aoka mizu floating, production, storage and offloading vessel successfully connected to the early production system on 19 march. Relationship between fractures, fault zones, stress, and. Here, we also consider basement rocks to include those of sedimentary origin with little or no matrix. Integrated study of a fractured granitic basement reservoir. People were quite rude and disparaging to me personally and the company even until about 2017, says trice. Fractured basement characteristics oil storage and mobility entirely depends on the fracture network recovery dominated by fracture network recovery dominated by rock properties type i type ii type iii type iv matrix porosity matrix permeability low high low high definitions of naturally fractured reservoirs, after nelson 2001 type 1. An application of the constrained conjugategradients leastsquares migration thang ha, kurt marfurt, and bin lyu university of oklahoma summary seismic inversion has become almost routine in quantitative 3d seismic interpretation. Donaldson, 2004 figure 11 fracture permeability as a function of the width and spacing of fractures. Two drill cores from the mesozoic maribshabwa basin, central yemen, penetrated the upper part. The outcome of experimental and theoretical investigation to determine the critical production rate for single and multi fractured system, the capillary pressure effect, and the breakthrough time presented. Naturally fractured reservoirs present a production paradox.
The most famous is the white tiger offshore oil field in the cuu long basin in vietnam. Natural fracture propping and earthquakeinduced oil. Oct 25, 2018 characterization of a fractured basement reservoir using highresolution 3d seismic and logging datasets. In the southern gulf of suez, egypt, several oil fields have been produced hydrocarbon from fractured basement, such as zeit bay, hilal, ashrafi and. Subsurface biodegradation of crude oil in a fractured basement reservoir, shropshire, uk. Lancaster development making fractured basement reserves viable november 2017 establishing, predicting and modelling the hydrodynamic fracture network of basement reservoirs during the exploration and early appraisal phase. The workshop will emphasizes of petrophysical evaluation and fractured reservoir, petrophysical parameters interpretation fractured basement reservoir. Subsurface biodegradation of crude oil in a fractured. The lancaster reservoir is the uks first fractured basement field and was granted field status in september 2015. Understanding basement fracture architecture in padra. Fractured basement reservoir is unconventional hydrocarbon reservoir where hydrocarbon storage and conductivity are provided by fracture system associated with faults. Penemuan potensi hidrokarbon dengan jumlah yang sangat besar telah ditemukan di batuan reservoir yang secara natural telah mengalami keretakan atau patahan fractured saat ini. Although it is possible that basement rocks may form reservoirs that are not in basement highs, petroleum exploration of basement rocks has focussed on highs.
Fractured basement reservoir characterization for fracture. Improving seismic image and impedance inversion of the texas. Water coning in fractured basement reservoirs onepetro. A comprehensive seismic analysis of fractured basement reservoirs was performed to identify the structural pattern and mechanism of hydrocarbon entrapment and reservoir. Fractured granite reservoirs the buried hill basement play in the cuu long basin is unusual in the fact that the shale source rocks are younger than the fractured reservoir. The most dominant facies in this well is the fractured basement with lots of conductive and resistive fractures.
Hurricane was established to discover, appraise and develop hydrocarbon resources from naturally fractured basement reservoirs. They are also notorious for early gas or water breakthrough. A novel approach of integrating the seismic geometrical and stratigraphic attributes, with the borehole image logs and core data were found to be useful to characterize fractured and weathered crystalline basement reservoir in the saraswati field located in the eastern margin of barmer basin. Characterization of fractured basement rese rvoir using. Furthermore, the volumes of hydrocarbons found within fractured basement can be significant and production rates can be high. The fracture porosity is defined as the percentage of the borehole wall which is represented by the. A casestudy of fractured basement reservoirs in damintun depression of liaohe basin. In fractured basement reservoirs, brittle rocks host are created more fractures than nonbrittle or ductile rocks. Uncertainty analyses of basement fracture reservoir performances. Hurricanes strategy is to create shareholder value through monetising the significant reserves and resources associated with the naturally fractured basement reservoirs within its portfolio through exploration. Characterization of a fractured basement reservoir using highresolution 3d seismic and logging datasets.