Geological reservoir modeling

Carbonate sediments within the Mid-Cretaceous Sarvak Formation form an important reservoir at the Abteymour oilfield in the western Dezful Embayment, SW Iran. The poroperm characteristics of this reservoir were controlled by factors including deposition under tropical climatic conditions and early diagenesis, repeated phases of subaerial exposure due to local, regional and global-scale tectonism, and diagenetic modification during burial. From microfacies analysis, the Sarvak Formation carbonates in the Abteymour field were interpreted in a previous study as having been deposited on a homoclinal ramp-type platform. Three third-order sequences were recognized in the middle Cenomanian to middle Turonian part of the formation. The reservoir quality of the carbonates was enhanced both by dissolution (comprising separate phases of eogenetic and telogenetic meteoric dissolution) and dolomitization (especially stylolite-related dolomitization).

In this paper, a rock/pore type approach was used in order to integrate petrophysical data with facies and diagenetic models within a sequence stratigraphic framework. Two different rock-typing methods for the determination of flow units were considered. Hydraulic flow units (HFUs) were identified firstly using flow zone indicators and secondly using a stratigraphic modified Lorenz plot. The flow units resulting from these two methods are compared, and their close correspondence within the sequence stratigraphic framework is discussed. In addition, the previously-used large-scale reservoir zonation scheme for the Abteymour field is correlated with the defined flow units, and four new Integrated Reservoir Zones are introduced. By integrating geological information with petrophysical parameters (including porosity, permeability and saturation) within a sequence stratigraphic framework, field-scale variations and controls on reservoir quality are described.

Recently developed data collection techniques allow for improved characterization of sedimentary outcrops. Here, we outline a workflow that utilizes unmanned aerial vehicles (UAV) and structure-from-motion (SfM) photogrammetry to produce sub-meter-scale outcrop reconstructions in 3-D. SfM photogrammetry uses multiple overlapping images and an image-based terrain extraction algorithm to reconstruct the location of individual points from the photographs in 3-D space. The results of this technique can be used to construct point clouds, orthomosaics, and digital surface models that can be imported into GIS and related software for further study. The accuracy of the reconstructed outcrops, with respect to an absolute framework, is improved with geotagged images or independently gathered ground control points, and the internal accuracy of 3-D reconstructions is sufficient for sub-meter scale measurements. We demonstrate this approach with a case study from central Utah, USA, where UAV-SfM data can help delineate complex features within Jurassic fluvial sandstones.

There is an insatiable thirst for oil and gas consumption and increased production will be made possible only
through effective reservoir characterization and modeling. A suite of wire-line logs for four wells from ‘DEL’ oil field
together with 3D seismic data were analyzed for reservoir characterization of the field. Two reservoirs were identified
using the resistivity log. A synthetic seismogram was generated in order to perform seismic to well tie process as
well as picking of horizons throughout the section. Time and depth structural maps were generated. Geostatistical
simulation such as the sequential Gaussian stimulation and sequential indicator stimulation were carried out to provide
equiprobable representations of the reservoirs, and the distribution of reservoir properties within the geological cells.
The modeled reservoir properties resulted in an improved description of reservoir distribution and inter connectivity.
The analysis indicated the presence of hydrocarbon in the reservoirs. There is also a fault assisted closure on the
structural map which is of interest in exploration. A fluid distribution plot and map of the field were also obtained. The
modeled properties gave an average porosity of 24%, average water saturation ranging from 12%-24% and moderate
net-gross. The volumetric calculation of the reservoir gives a STOIIP ranging from 37.53 MMbbl-43.03 MMbbl. The
result showed high hydrocarbon potential and a reservoir system whose performance is considered satisfactory for
hydrocarbon production. The resulting models can also be used to predict the future performance of the reservoir.

Abstract: At the beginning of 2015, Lublin Coal Bogdanka SA submitted an updated version the Company's strategy to 2020, which included several scenarios which assume continued development and exploitation of mines in areas adjacent to the Puchaczow V mining area. Each scenario was built on the basis of the geological model of the deposit and the production schedule for the exhaustion of resources taking in deposits different variants provide prospective deposits . Based on the calculated schedules, the Company's economic and financial models for the future were created.
The geological model is a digital, computer representation of a mineral deposit, representing some aspects such as: its localization, geometry and spatial differentiation of quality minerals. The deposit model is primarily a tool or workshop for geologist interpreting and documenting the geological structure of the deposit. It facilitates the creation of: an accurate description of the spatial structure of deposits, the quality of the mineral, hydrogeology, geological engineering and others. Visualization is an integral part of the tools for modeling deposits which provides an the understanding of the geological structure of complex deposits and allows the user to present it in an interesting manner. The geological database, which is usually part of the system modeling of the deposit, facilitates the management of large collections of geological data and makes it easier to
control the quality of the data.
The beginning of the implementation of each production plan is a digital model of the deposit, which is the base for the effective management of the resource base of each mine. According to practice, the reliable model of the deposit allows geological resources to be measured precisely, taking the qualitative and quantitative data into account. Respective variants are prepared on the basis of the created model.
This article provides a description of the process of creating a geological model for prospective deposits of LW Bogdanka SA.

Streszczenie: Lubelski Węgiel Bogdanka SA na początku 2015 roku przedstawiła aktualizację strategii spółki do 2020 roku, która zawierała kilka scenariuszy zakładających dalszy rozwój kopalni i eksploatację w obszarach przylegających do OG „Puchaczów V". Każdy ze scenariuszy budowany był na podstawie geologicznego modelu złoża i harmonogramu produkcji do sczerpania zasobów, przyjmując różne warianty udostępnienia złóż perspektywicznych. Tak przygotowane harmonogramy były podstawą dla konstrukcji modelu ekonomiczno-finansowego spółki na przyszłe lata.
Model złoża to cyfrowa, komputerowa prezentacja złoża kopaliny przedstawiająca wybrane aspekty geologii złoża, w tym jego położenie, geometrię oraz przestrzenne zróżnicowanie jakości. Model złoża to przede wszystkim narzędzie czy też warsztat pracy geologa interpretującego i dokumentującego budowę geologiczną złoża.
Ułatwia on stworzenie dokładnego, przestrzennego opisu struktury złoża, jakości kopaliny, warunków hydrogeologicznych, geologiczno-inżynierskich i innych. Możliwości wizualizacyjne stanowiące nieodłączną część narzędzi informatycznych do modelowania złóż ułatwiają zrozumienie budowy geologicznej nawet bardzo skomplikowanych złóż i pozwalają zaprezentować ją w interesujący sposób. Geologiczna baza danych, będąca zwykle elementem systemu do modelowania złoża, ułatwia zarządzanie dużymi zbiorami danych geologicznych i jest niezwykle pomocne przy kontroli jakości tych danych.
Początkiem realizacji każdego planu produkcji jest cyfrowy model złoża, który jest fundamentem efektywnego zarządzania bazą zasobową każdej kopalni. W ocenie praktycznej, prawidłowo wykonany model złoża pozwala na dokładne określenie zasobów geologicznych z uwzględnieniem danych jakościowych i ilościowych. Jest on
podstawą dla wariantowej analizy harmonogramów produkcji.
Niniejszy artykuł przedstawia opis procesu tworzenia modelu geologicznego dla złóż perspektywicznych LW Bogdanka SA.

This paper presents an investigation of naturally occurring CO2 emissions from the Florina natural analogue site in Greece. The main objective was to interpret previously collected depth sounding data, convert them into surfaces, and use them as input to develop, for the first time, 3D geological models of the Florina basin. By also locating the extent of the aquifer, the location of the CO2 source, the location of other natural CO2 accumulations, and the points where CO2 reaches the surface, we were able to assess the potential for CO2 leakage. Geological models provided an estimate of the lithological composition of the Florina Basin and allowed us to determine possible directions of groundwater flow and pathways of CO2 flow throughout the basin. Important modelling parameters included the spatial positions of boundaries, faults, and major stratigraphic units (which were subdivided into layers of cells). We used various functions in Petrel software to first construct a structural ...

This paper presents an investigation of naturally occurring CO2 emissions from the Florina natural analogue site in Greece. The main objective was to interpret previously collected depth sounding data, convert them into surfaces, and use them as input to develop, for the first time, 3D geological models of the Florina basin. By also locating the extent of the aquifer, the location of the CO2 source, the location of other natural CO2 accumulations, and the points where CO2 reaches the surface, we were able to assess the potential for CO2 leakage. Geological models provided an estimate of the lithological composition of the Florina Basin and allowed us to determine possible directions of groundwater flow and pathways of CO2 flow throughout the basin. Important modelling parameters included the spatial positions of boundaries, faults, and major stratigraphic units (which were subdivided into layers of cells). We used various functions in Petrel software to first construct a structural ...