Academic literature on the topic 'Multimineral method'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Multimineral method.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Multimineral method"
1
Cheng, Liwei, Manika Prasad, Reinaldo J. Michelena, et al. "Using rock-physics models to validate rock composition from multimineral log analysis." GEOPHYSICS 87, no. 2 (2022): MR49—MR62. http://dx.doi.org/10.1190/geo2020-0918.1.
Full textAbstract:
Multimineral log analysis is a quantitative formation evaluation tool for geologic and petrophysical reservoir characterization. Rock composition can be estimated by solving equations that relate log measurements to the petrophysical endpoints of minerals and fluids. Due to errors in log data and uncertainties in petrophysical endpoints of constituents, we have used effective medium models from rock physics as additional independent information to validate or constrain the results. We examine the Voigt-Reuss (VR) bound model, self-consistent approximation (SCA), and differential effective medium (DEM). The VR bound model provides the first-order quality control of multimineral results. We first show a conventional carbonate reservoir study with intervals in which the predicted effective medium models from multimineral results are inconsistent with measured elastic properties. We use the VR bound model as an inequality constraint in multimineral analysis for plausible alternative solutions. The SCA and DEM models provide good estimates in low-porosity intervals and imply geologic information for porous intervals. Then, we present a field case of the Bakken and Three Forks formations. A linear interpolation of the VR bound model helps validate multimineral results and approximate the elastic moduli of clay. There are two major advantages to using our new method: (1) Rock-physics effective medium models provide independent quality control of petrophysical multimineral results and (2) multimineral information leads to realistic rock-physics models.
2
Feng, Zhou, Xin-Tong Li, Hong-Liang Wu, Shou-Ji Xia, and Ying-Ming Liu. "Multimineral optimization processing method based on elemental capture spectroscopy logging." Applied Geophysics 11, no. 1 (2014): 41–49. http://dx.doi.org/10.1007/s11770-014-0419-3.
Full text
3
Li, Xuejiao, Wensheng Wang, Zhiqing Zhu, and Kunkun Zheng. "Investigation on Durability Behaviour and Optimization of Concrete with Triple-Admixtures Subjected to Freeze-Thaw Cycles in Salt Solution." Advances in Materials Science and Engineering 2021 (February 9, 2021): 1–16. http://dx.doi.org/10.1155/2021/5572011.
Full textAbstract:
In the seasonal frozen area of northeast China, cement concrete is usually in a working environment of cold climate and chlorine erosion coupling effect. In general, with a reasonable addition of air entraining agent (AEA) and multimineral admixtures such as fly ash, blast furnace slag, and silica fume, the durability of cement concrete under the effects of freeze-thaw and salt solution can be significantly improved in cold regions. However, due to several more compositions of cement concrete with multiple mineral admixtures, it would take excessive trial mixtures to select the desired mixture proportion based on the conventional method. This means a great deal of costs of raw materials and laboratory experimental time. In this paper, the experimental scheme of mixture proportion for air-entrained concrete with multimineral admixtures was designed based on the orthogonal experiment design method. Based on the compressive strength, rapid chloride permeability, and weight loss and relative dynamic elastic modulus after salt freeze-thaw cycles, the influence of different mineral admixtures and their dosages on the durability of concrete subjected to freeze-thaw in salt solution was analyzed. After that, based on genetic algorithm, an optimization of mixture proportion was proposed, which only requires less trial mixes and accessible optimization process. The test results indicated the superiority of air-entrained concrete with multimineral admixtures when serving in salt freeze-thaw environment. Eventually, it was also verified that the optimized concrete in this paper could achieve pleasurable durability performances under salt freeze-thaw cycles.
4
Chen, Pei, Renata Atkinson, and Wayne R. Wolf. "Single-Laboratory Validation of a High-Performance Liquid Chromatographic-Diode Array Detector-Fluorescence Detector/Mass Spectrometric Method for Simultaneous Determination of Water-Soluble Vitamins in Multivitamin Dietary Tablets." Journal of AOAC INTERNATIONAL 92, no. 2 (2009): 680–88. http://dx.doi.org/10.1093/jaoac/92.2.680.
Full textAbstract:
Abstract The purpose of this study was to develop a single-laboratory validated (SLV) method using high-performance liquid chromatography with different detectors diode array detector (DAD); fluorescence detector (FLD); and mass spectrometry (MS) for determination of 7 B-complex vitamins (B1-thiamin, B2-riboflavin, B3-nicotinamide, B6-pyridoxine, B9-folic acid, pantothenic acid, and biotin) and vitamin C in multivitamin/multimineral dietary supplements. The method involves the use of a reversed-phase octadecylsilyl column (4 m, 250 2.0 mm id) and a gradient mobile phase profile. Gradient elution was performed at a flow rate of 0.25 mL/min. After a 5 min isocratic elution at 100 A (0.1 formic acid in water), a linear gradient to 50 A and 50 B (0.1 formic acid in acetonitrile) at 15 min was employed. Detection was performed with a DAD as well as either an FLD or a triple-quadrupole MS detector in the multiple reaction monitoring mode. SLV was performed using Standard Reference Material (SRM) 3280 Multivitamin/Multimineral Tablets, being developed by the National Institute of Standards and Technology, with support by the Office of Dietary Supplements of the National Institutes of Health. Phosphate buffer (10 mM, pH 2.0) extracts of the NIST SRM 3280 were analyzed by the liquid chromatographic (LC)-DAD-FLD/MS method. Following extraction, the method does not require any sample cleanup/preconcentration steps except centrifugation and filtration.
5
Saroji, Sudarmaji, Wandia Mellani Trihapsari, and Muhammad Destrayuda Trisna. "Implementation of Deterministic and Multimineral Method in Petrophysical Analysis for Identifying Low Resistivity Reservoir in Tesla Field, Air Benakat Formation, South Sumatera Basin." Aceh International Journal of Science and Technology 13, no. 3 (2025): 180–92. https://doi.org/10.13170/aijst.13.3.36698.
Full textAbstract:
The Tesla field is located in the South Sumatra Basin, where there is the Air Benakat Formation, with the constituent rocks being dominated by alternating sandstone and claystone so that it is a shaly sand environment with the potential to become a low-resistivity hydrocarbon reservoir. Hydrocarbon reservoirs generally have a resistivity log value of more than 10 Ωm; when a hydrocarbon reservoir has a low-resistivity value between 0.5 - 5 Ωm, it is referred to as a low-resistivity hydrocarbon reservoir. Initially, deterministic analysis was carried out to calculate the petrophysical parameters of the potentially low-resistivity reservoirs. However, the results show a low validation value of petrophysics parameters, such as effective porosity and water saturation, when compared to the DST data, so a multimineral analysis is carried out to increase the validation value of the petrophysical parameters. The use of the multimineral method has produced the petrophysics parameter closer to DST Data when compared to the petrophysics parameter produced by the deterministic method in Tesla Field. The formation analysis shows that the low resistivity reservoir in the Tesla Field is caused by the grain size of the sandstone, which is very fine so that it can bind water significantly (irreducible water), abundant shale content, and distributed by lamination of shale, dispersed shale, and structural shale as well as the presence of conductive glauconite minerals.
6
Felice, Valeria, Denise O’Gorman, Nora O’Brien, and Niall Hyland. "Bioaccessibility and Bioavailability of a Marine-Derived Multimineral, Aquamin-Magnesium." Nutrients 10, no. 7 (2018): 912. http://dx.doi.org/10.3390/nu10070912.
Full textAbstract:
Introduction: Magnesium is an essential mineral involved in a range of key biochemical pathways. Several magnesium supplements are present on the market and their degree of bioavailability differs depending on the form of magnesium salt used. Aquamin-Mg is a natural source of magnesium, containing 72 additional trace minerals derived from the clean waters off the Irish coast. However, the in vitro bioaccessibility and bioavailability of Aquamin-Mg in comparison with other supplement sources of magnesium has yet to be tested. Method: Aquamin-Mg, magnesium chloride (MgCl2) and magnesium oxide (MgO) were subjected to gastrointestinal digestion according to the harmonized INFOGEST in vitro digestion method and in vitro bioavailability tested using the Caco-2 cell model. Magnesium concentration was measured by atomic absorption spectrophotometry (AAS). Results: Magnesium recovery from both Aquamin-Mg and MgCl2 was greater than for MgO. Magnesium from all three sources was transported across the epithelial monolayer with Aquamin-Mg displaying a comparable profile to the more bioavailable MgCl2. Conclusions: Our data support that magnesium derived from a marine-derived multimineral product is bioavailable to a significantly greater degree than MgO and displays a similar profile to the more bioavailable MgCl2 and may offer additional health benefits given its multimineral profile.
7
Clarke, D. L., and A. P. Clare. "AN INTEGRATED PETROPHYSICAL WORKFLOW TO GENERATING FLUID SUBSTITUTED LOGS FOR AVO CHARACTERISATION—GIPSY AND NORTH GIPSY FIELDS CASE STUDY, NORTH WEST SHELF, AUSTRALIA." APPEA Journal 42, no. 1 (2002): 477. http://dx.doi.org/10.1071/aj01026.
Full textAbstract:
As part of a multi-well field study an integrated petrophysical workflow was developed to include the generation of fluid substituted logs for AVO characterisation.The workflow relied upon the construction of a multimineral model that best approximated the actual mineral content of the reservoir. Any limitations or assumptions were noted and taken into account when creating the multi-mineral model. Other petrophysical results were derived from the same model to validate its consistency such as intrinsic permeability, porosity, water saturation, etc. Iteration between the model and the results was required until a consistent model was achieved.The estimation of an intrinsic permeability log was based upon the k-Lambda method that uses the multimineral model and porosities.The estimation of a shear slowness log and the fluid substituted logs was based upon elastic rock properties derived from the multi-mineral model and the acquired compressional slowness log and bulk density log. This integrated approach provides a higher confidence in the derived results, which are then used as input into the reservoir model, thereby improving the reserve calculations.The interdependence of each derived result on the same input multi-mineral model ensures consistency and predictability in a complex geological environment, which captures all available information.The method is demonstrated with the Gipsy–1 and North Gipsy–1 wells, which were part of the original field study.
8
Nicolás-López, Rubén, Oscar C. Valdiviezo-Mijangos, Jaime Meléndez-Martínez, and Valeriy M. Levin. "A multimineral Rock Physics Template built from the Perfectly Disordered Method for shale lithology interpretation." Journal of Petroleum Science and Engineering 176 (May 2019): 532–36. http://dx.doi.org/10.1016/j.petrol.2019.01.095.
Full text
9
Liu, Mingxin, Yongfei Yang, Fugui Liu, et al. "Thermal disturbance anisotropy and structural stability in deep multimineral granular systems: A discrete element method study." Geothermics 132 (November 2025): 103439. https://doi.org/10.1016/j.geothermics.2025.103439.
Full text
10
Burke, Lauri A., Justin E. Birdwell, and Stanley T. Paxton. "Multimineral petrophysics of thermally immature Eagle Ford Group and Cretaceous mudstones, U.S. Geological Survey Gulf Coast 1 research wellbore in central Texas." Interpretation 10, no. 1 (2021): T151—T165. http://dx.doi.org/10.1190/int-2021-0094.1.
Full textAbstract:
Traditional petrophysical methods to evaluate organic richness and mineralogy using gamma-ray and resistivity log responses are not diagnostic in source rocks. We have developed a deterministic, nonproprietary method to quantify formation variability in total organic carbon (TOC) and three key mudrock mineralogical components of nonhydrocarbon-bearing source rock strata of the Eagle Ford Group by developing a set of log-derived multimineral models calibrated with Fourier transform infrared spectroscopy core data from the research borehole U.S. Geological Survey Gulf Coast 1 West Woodway. We determined that bulk density response is a reliable indicator of organic content in these thermally immature, water-bearing source rocks. Multimineral findings indicate that a high degree of laminae-scale mineralogical heterogeneity exists due to thinly interbedded carbonate cements amid clay-rich mudstone layers. The lower part of the Eagle Ford Group contains the highest average TOC content (4.7 wt%) and the highest average carbonate volume (64.1 vol%), making it the optimal target in thermally mature areas for source-rock potential and hydraulic-fracture placement. In contrast, the uppermost portion of the Eagle Ford Group contains the highest average volume of clay minerals (42.6 vol%), which increases the potential for wellbore stability issues. Petrophysical characterization reveals that porosity is approximately 30% in this relatively uncompacted formation. In this thermally immature source rock, water saturation is nearly 100% and no free hydrocarbons were observed on the resistivity logs. No evidence of borehole ellipticity was observed on the three-arm caliper log, and horizontal stresses are presumed to be directionally uniform in the vicinity of this near-surface wellbore. This shallow wellbore has a temperature gradient of 1.87°F/100 ft (16.3°C/km) and is likely influenced by earth surface heating.
Dissertations / Theses on the topic "Multimineral method"
1
LIANG, WENDONG. "Petrology and multimineral fingerprinting of modern sand derived from the Himalayan orogen." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/271022.
Full textAbstract:
L’oggetto di questa tesi è stato lo studio della mineralogia dei sedimenti fluviali ed eolici attuali generati dall’erosione della catena Himalayana, con lo scopo di definire con precisione le segnature composizionali dei diversi domini tettono-stratigrafici dell’orogene.
All’approccio basato sulla identificazione e quantificazione delle associazioni di minerali pesanti (densità > 2.90 g/cm3), sono stati affiancate diverse tecniche analitiche complementari, che comprendono la petrografia e la geochimica del sedimento totale, lo studio di dettaglio al microscopio elettronico a scansione e allo spettroscopio Raman delle caratteristiche minerochimiche dei quattro principali gruppi di minerali pesanti che caratterizzano i sedimenti himalayani e orogenici in generale (anfiboli, epidoti, granati, e pirosseni), l’ analisi dei rapporti isotopici di samario e neodimio scolta in collaborazione con Peter Clift presso l’ Istituto Oceanigrafico Woods Hole, oltre all’ analisi geocronologica su zirconi detritici svolta in collaborazione con Pieter Vermeesch presso l’Università di Londra (UCL) affiancata anche da dati analoghi su rutilo, monazite, e titanite ottenuti con la collaborazione di Xiumian Hu e Ronghua Guo presso l’ Università di Nanjing.
Le principali aree di studio hanno compreso il Deserto di Thal nel Pakistan centro-settentrionale e gli affluenti del Fiume Indo nel suo corso di montagna dal Ladakh fino al Punjab e gli affluenti principali del Fiume Yarlung (il nome tibetano del Brahmaputra) in Tibet meridionale. Sono stati studiati anche campioni di arenarie Cenozoiche provenienti sia dalle Alpi Occidentali che dal Tibet meridionale. I risultati presentati in questa tesi sono stati pubblicati a primo nome in un volume speciale della rivista internazionale Minerals, sono stati sottomessi nel mese di Settembre e sempre a primo nome a Sedimentary Geology, o sono in preparazione per una prossima sottomissione ad altra prestigiosa rivista internazionale.<br>Sediments and sedimentary rocks can be considered as geological archives that faithfully reflect their provenance information if the bias introduced by physical and chemical processes during transport and deposition can be properly recognized and corrected for. The sediment provenance analysis both in modern and ancient settings is crucial to trace the sediment sources, reconstruct paleoclimate and paleoenvironment, and interpret the evolution of the Earth’s surface.
Modern sediments, unaffected by diagenesis and eroded, tansported and deposited under climatic conditions that are fully known, can provide valuable information on the interactions among the different controlling factors that govern source-to-sink systems. Rivers draining the Himalayan orogen provide the good opportunity to trace the source fingerprinting that is documented in modern fluvial and eolian sand and how these signatures reflect the erosion patterns of the modern and paleo-river systems. A multidisciplinary approach based on petrography, minerology, geochemistry and geochronology is emphasized in this research, in order to obtain a comprehensive provenance information.
Our research area focused on the modern sands from two river system: Yarlung River and Indus River. In the Yarlung River system, the Nian River was chosen to investigate the petrographic, mineralogical and chronological signature of sediments from Tethys Himalaya, Greater Himalaya, Kangmar gneiss dome and Transhimalayan ophiolitic suture. Different tectonic domains are characterized by distinct heavy mineral assemblages, e.g., the first-cycle sillimanite and garnet in Greater Himalaya, and clinopyroxene, olivine and enstatite in the forearc ophiolites. Sand carried by the Nian River and its major tributaries, mainly reflects Tethys Himalayan characteristics, consistent with the geochronological results. Erosion rates were also evaluated and circumscribed in the middle Yarlung River catchment. The average erosion rate in the Nianchu catchment is estimated at 0.07-0.10 mm/a, twice as that in the middle Yarlung and Lhasa River catchments, which is principally ascribed to the high erodibility of Tethys Himalayan strata.
In the Indus River system, minerochemical analysis of amphibole, garnet, epidote and pyroxene grains, and geochronological analysis of detrital zircons, associated with analysis on petrography, bulk-sediment geochemistry and isotopic geochemistry, in aolian sand from Thal Desert and fluvial sand in selected tributaries draining one specific tectonic domain in the upper Indus catchment, were carried out to discriminate compositional signatures, decipher the provenance information, and trace the erosional evolution of the western Himalaya syntaxis. The compositional fingerprints of Thal Desert sand are characterized by litho-feldspatho-quartzose to quartzo-feldspatho-lithic detrital modes and very rich amphibole-dominated heavy-mineral assemblages. The high heavy mineral concentration, less negative εNd, abundant zircon ages at 40-100 Ma, and specific mineral varietal fingerprints, consistently reflect that the Kohistan arc has acted as the main sediment source. Karakorum appears to contribute less while Himalaya shows higher influence on the Thal Desert sands than modern river sands from the Indus. As a Quaternary repository of wind-reworked Indus River sand at the entry point in the Himalayan foreland basin, Thal Desert sands document higher erosion rates than today in the glaciated areas formed largely by batholites granitoids of the Asian active margin. The close compositional and chronological connection between the Thal Desert and the ancient Indus Delta and Fan deposits, shed new light on the reconstructing of paleodrainage and the understanding of relationship between climatic and tectonic forcing that controlled the erosional evolution of the western Himalayan-Karakorum orogen.
Conference papers on the topic "Multimineral method"
1
Wang, S. S., L. Z. Xiao, A. Z. Yue, and X. Li. "Multimineral non-linear inversion method using geochemical logging data based on Tikhonov regularization." In 79th EAGE Conference and Exhibition 2017. EAGE Publications BV, 2017. http://dx.doi.org/10.3997/2214-4609.201701048.
Full text
2
Sapiie, B. "Fault Seal Analysis Application in Carbonate Rock Sequences: Issues and Solution." In Indonesian Petroleum Association - 46th Annual Convention & Exhibition 2022. Indonesian Petroleum Association, 2022. http://dx.doi.org/10.29118/ipa22-g-303.
Full textAbstract:
Fault seal analysis (FSA) is a crucial component of hydrocarbon exploration, production, and reservoir management. However, most FSA workflow and theories are developed for normal fault systems that commonly apply to siliciclastic rock. In the case of the carbonate rock, a simple algorithm of FSA using shale gouge ratio (SGR) analysis may generate some errors in sealing and leaking faults. The FSA method is primarily controlled by shale volume distributions rather than by throw, as demonstrated by sealing faults behavior with small throws. This result suggested that good quality sand reservoir distributions become the primary control for the fault sealing capacity. There are three approaches to determining the clay volume: (1) the gamma-ray clay volume calculation, (2) dual parameter (gamma-ray and NPHI-RHOB) clay volume calculation, and (3) multimineral analysis results (probabilistic approach) clay volume calculation. However, carbonate rock sequences have low concentrations of radioactive material that give low gamma-ray readings and SGR values. Therefore, the shale volume value must be calculated using modified petrophysical approaches for better sealing capacity distributions. A detailed FSA study was carried out using integrated research of fieldwork and shallow drilling core data. This field study was in the Rajamandala Carbonate Complex in the Padalarang area. The result of the study will become the focus of this paper. The evaluation involves five core data from shallow drilling at various levels of the Cikamuning normal fault supported by field mapping, thin sections, and XRD. The tentative results suggested that fault gouge in the carbonate rock sequences is complex and varies significantly in composition, thickness, and diagenetic. Further detailed works need to be done, particularly with deep core data.
3
Vasić, Goran. "Microelements and sports performance." In Antropološki i teoantropološki pogled na fizičke aktivnosti (11). Univerzitet u Prištini-Kosovska Mitrovica - Fakultet za sport i fizičko vaspitanje u Leposaviću, Leposavić, 2025. https://doi.org/10.5937/atavpa25001v.
Full textAbstract:
Athletes who take care of their health and want to be successful in sports take various vitamin and multimineral supplements, but most of them don't pay attention to traces of microelements found in human body. Studies state that 72 of them are needed in order for human to function properly. While only 8 microelements can be found in soil, and therefore in food, all of the 72 can be found in some type of seafood. Those who don't consume enough food of this kind can get their necessary doses of trace elements from multimineral supplements. The effects of microelements on the human body are great. By meeting daily needs, they can improve overall health and sports performance, but deficiency of just one of the trace elements can cause a number of health problems. lack of some microelements can lead to depression or sudden mood changes, while a lack of iron can lead to reduced energy production, a lack of iodine will cause problems in terms of intelligence, and if there is a lack of chromium, it could cause diabetes. The influence of trace elements is so far-reaching that it is thought that they can even affect the lifespans of people. Unfortunately, modern methods of food preparation and storage often remove trace elements and other essential minerals from the food we eat. This is the reason why supplements in the form of rich, high-quality multimineral and vitamin preparations are necessary to compensate for nutritional deficiencies.
4
Mellal, Ilyas, Mohamed Lamine Malki, Abdeldjalil Latrach, Ouafi Ameur-Zaimeche, and Omar Bakelli. "Multiscale Formation Evaluation and Rock Types Identification in the Middle Bakken Formation." In 2023 SPWLA 64th Annual Symposium. Society of Petrophysicists and Well Log Analysts, 2023. http://dx.doi.org/10.30632/spwla-2023-0012.
Full textAbstract:
Multiple challenges are associated when characterizing complex reservoirs using well logs. The Middle Bakken Member (MBM), as a tight and multimineral reservoir with a low-resistivity pay, presents several petrophysical challenges. The objective of the paper is to characterize the MBM rock properties from pore to log scale using thin sections, routine and special core analysis, conventional and advanced well logs, and machine-learning algorithms. For a detailed understanding of the MBM rock properties, we used a complex petrophysical workflow by integrating quad-combo logs along with advanced logs, including electron capture spectroscopy and nuclear magnetic resonance (NMR), using both deterministic and probabilistic methods. Bakken minerals and fluids volumes were estimated by combining quad-combo logs along with elemental dry-weight fractions and calibrated with the X-ray diffraction (XRD) and routine core analysis data. Porosity, clay-bound water, and movable fluids were estimated using NMR. Due to the low-resistivity reading in the reservoir and the inaccuracy of the water saturation and permeability estimated from well logs, thin sections from different depths of the MBM were analyzed to understand the pore types, cementing materials, and grain packing. Finally, machine-learning algorithms were applied in a total of 1,503 Dean-Stark water saturation samples using the triple-combo logs to estimate water saturation and generalize the results in the North Dakota portion of the MBM. We found that from the multimineral model of the evaluated wells that the MBM is composed of six main minerals, where quartz and dolomite are the main minerals of the reservoir. The model provided an accurate prediction of the minerals compared to the XRD analysis, except for some scattered XRD points, which are assumed to be due to the laminations that exist in the reservoir. Archie derivatives were tested in the Bakken using constant Archie parameters to estimate water saturation; the results showed a disagreement with the Dean-Stark water saturation. By analyzing thin sections, we found that three minerals act as a cementing material, and their volume varies along the reservoir, which makes the estimation of the cementing exponent constant along the reservoir interval a wrong approach. Machine-learning algorithms were employed to predict water saturation from the triple-combo logs. Several models were compared: linear regression, ridge regression, support vector machines, neural networks with backpropagation, and decision trees. For the comparison, both correlation coefficient and mean squared error were used. Decision trees proved to be the most reliable model, with an R2 of 0.87. The decision trees model gave almost perfect predictions, except for a few outliers that lowered the correlation coefficient. This relatively simple model proved to be a powerful tool for predicting the water saturation in the MBM. Machine-learning-based models proved to be a robust tool for water saturation prediction in the MBM and outperformed the classical physical and analytical models. Furthermore, the used decision-trees-based model is a white box model whose parameters can be extracted and interpreted.
5
Issayev, Duman, Francisco Correa Mora, Assem Bibolova, et al. "Fast-Track Verification Methods for Optimizing the Strategy and Scope of a Static Model Rebuild." In SPE Caspian Technical Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/217512-ms.
Full textAbstract:
Abstract Oil field production forecasts rely heavily on an accurate characterization of the subsurface. Static geological models are computer-based three-dimensional representations of the subsurface that approximate the reservoir properties and are the basis for dynamic simulation and subsequent field development decisions. With the advent of new data acquisition technologies, the prompt availability of additional information can potentially impact the validity and reliability of existing geological models. This case study introduces accelerated verification methods to evaluate the scope of a static model rebuild to accommodate business decisions. Recent development efforts in the Tengiz oil field have led to the acquisition of new data, including the drilling of new wells and well log acquisition, reprocessing of seismic data, and microseismicity. Drilling new wells has provided valuable information about the reservoir's petrophysical properties. Specifically, high-resolution well logs, including wellbore images, helped derive valuable information about lithology, porosity, and fluid saturation, leading not only to a more accurate petrophysical interpretation but also help to define local variations of reservoir quality, allowing for more precise reservoir characterization. Reprocessed seismic data has improved image quality and event positioning, enabling improved structural mapping and seismic mega-amplitude detection. New wells with drilling data, wireline and production logs also provided additional information about fracture orientations, aperture, and density. A fast-track, fit-for-purpose geological model was built through effective communication and collaboration among multidisciplinary teams and using fit-for-purpose quantitative and qualitative techniques, including 2D methodologies, statistical analysis, and geostatistical modeling. The main seismic horizons were reinterpreted from newly reprocessed seismic. New wellbore data was prioritized based on available logs and the existing data coverage. Matrix porosity and water saturation were calculated using a multimineral inversion model; fracture orientations were picked from image logs and fracture intensity and porosity were quantified. Quality control included statistical and variogram analyses before porosity propagation in a 3D model, which allowed for assessing a change in matrix and fracture porosity and pore volume in the model. A standard data-driven dual-porosity dual-permeability property modeling workflow was leveraged with microseismicity data to define effective fracture regions for the discrete fracture network model. These fast-track modeling approaches, developed in a time-efficient period, enabled the maturation of techniques to be applied in a future next-generation static model and provided valuable insights for reservoir management and production optimization in the Tengiz oil field.
6
Lee, Hyungjoo, Alexander Mitkus, Andrew Pare, et al. "A New Workflow for Estimating Reservoir Properties With Gradient Boosting Modeland Joint Inversion Using MWD Measurements." In 2023 SPWLA 64th Annual Symposium. Society of Petrophysicists and Well Log Analysts, 2023. http://dx.doi.org/10.30632/spwla-2023-0044.
Full textAbstract:
Triple-combo logs are important measurements for estimating geological, petrophysical, and geomechanical properties. Unfortunately, wireline and advanced LWD logs are typically dropped from the formation evaluation plan for unconventional wells due to economic constraints or borehole instability risks. Available measurements are typically measurement-while-drilling (MWD) natural gamma ray (GR) logs, along with surface measurements such as weight on bit (WOB), rate of penetration (ROP), torque, revolutions per minute (RPM), and differential pressure. The development of a robust and rapid model for predicting reservoir properties using this limited data set would be of high value for geological evaluation. Estimating such properties is a challenging task due to the nonlinear relationship between the available log data and unknown reservoir properties. A novel workflow is presented that combines two sequential models. First is a machine-learning algorithm to predict triple-combo logs from drilling dynamic measurements and GR logs. To train the machine-learning algorithm, well logs obtained from multiple wells located in the Eagle Ford and Permian Basins are scrutinized to identify important features. This process includes depth shifting, outlier detection, and feature selection, which allows for strategic hyperparameter tuning. Several regression algorithms are investigated, and it is found that gradient boosting algorithms yield superior prediction performance. Unlike commonly used regressors such as random forest methods, boosting algorithms train predictors sequentially, each trying to correct its predecessor. After triple-combo logs are predicted from measurement-while-drilling (MWD) logs, a physics-based joint inversion model is applied to estimate reservoir properties such as total porosity, clay volume, water saturation, volumetric concentrations of lithology, permeability, rock type, and geomechanical parameters. The trained model is deployed on a blind test well, and the predicted logs show excellent agreement when compared to the corresponding triple-combo measurements. The multimineral inversion using predicted triple-combo logs yields a geologic model that is validated with both mud logs and ECS measurements. Therefore, real-time estimated geological, petrophysical, and geomechanical properties can reveal complex geologic information to mitigate uncertainty related to drilling optimization, reservoir characterization, development plan, and reserve estimate. Using the MWD logs to predict triple-combo logs followed by a joint inversion is an innovative approach for a geological evaluation with a limited data set. The developed workflow can successfully provide (1) geologic lithofacies identification and rock typing, (2) more confidence in real-time drilling operation, (3) reservoir properties prediction, (4) missing log imputations and pseudo-log generation with forward modeling, (5) guidance for future logging and perforation (6) reference for seismic QI and well tie, and (7) computation time saving from days to minutes.