The Experts below are selected from a list of 38613 Experts worldwide ranked by ideXlab platform
Ricardo I F Trindade - One of the best experts on this subject based on the ideXlab platform.
-
rare earth elements in the terminal ediacaran bambui group Carbonate Rocks brazil evidence for high seawater alkalinity during rise of early animals
Precambrian Research, 2020Co-Authors: Gustavo M Paulasantos, Sergio Caetanofilho, Jacinta Enzweiler, Margareth Sugano Navarro, Marly Babinski, Cristian Guacaneme, Matheus Kuchenbecker, Humberto L S Reis, Ricardo I F TrindadeAbstract:Abstract Rare earth elements plus yttrium (REY) mass fractions of ancient Carbonate Rocks are used to track changes in chemistry of past seawater. Here we investigate REY patterns in two Carbonate sections from the Ediacaran Bambui Group, Sao Francisco Basin (Brazil), which comprise its two lowermost transgressive-regressive second-order sedimentary sequences. Shale normalised distributions vary with the sequence stratigraphy framework. In the basal 2nd-order sequence, Carbonate samples from the basal sequence transgressive systems tract display light REY (LREY) distributions slightly depleted to enriched that reflect input of freshwater, possibly in a post glacial episode. Upwards, Carbonate Rocks from the early highstand systems tract (EHST) yielded LREY enriched distributions, which progressively turns into LREY shale normalized depleted distributions on samples from the late highstand systems tract (LHST). This portion of the sequence also displays Y positive anomaly in some cases. Carbonate samples from the upper second-order sequence do not display coherent patterns. Ce/Ce* values > 1 in most samples throughout the two sections suggest permanent anoxia of seawater. The REY change from the EHST to LHST in the basal sequence marks an important paleoenvironmental overturn in the basin, with increasing alkalinity in seawater driving REY fractionation and LREY depletion. Confinement of the basin in the inner areas of West Gondwana due the uplift of marginal neoproterozoic orogens probably changed the weathering style of source areas to more congruent, thus delivering a higher ionic influx to a restricted setting, increasing alkalinity during LHST. Cloudina sp. fragments were reported in this stage of the Bambui Group and in Carbonate Rocks with high Sr mass fractions in other West Gondwana basins, supporting the hypothesis that the high alkalinity of seawater during late Ediacaran may have driven the appearance of the first biomineralizing organisms.
Nathaly Lopes Archilha - One of the best experts on this subject based on the ideXlab platform.
-
permeability and acoustic velocity controlling factors determined from x ray tomography images of Carbonate Rocks
AAPG Bulletin, 2016Co-Authors: Nathaly Lopes Archilha, Cathy Hollis, Roseane M Missagia, Marco Ceia, S A Mcdonald, Irineu Lima Neto, David S EastwoodAbstract:Carbonate reservoir Rocks exhibit a great variability in texture that directly impacts petrophysical parameters. Many exhibit bi- and multimodal pore networks, with pores ranging from less than 1 μm to several millimeters in diameter. Furthermore, many pore systems are too large to be captured by routine core analysis, and well logs average total porosity over different volumes. Consequently, prediction of Carbonate properties from seismic data and log interpretation is still a challenge. In particular, amplitude versus offset classification systems developed for clastic Rocks, which are dominated by connected, intergranular, unimodal pore networks, are not applicable to Carbonate Rocks. Pore geometrical parameters derived from digital image analysis (DIA) of thin sections were recently used to improve the coefficient of determination of velocity and permeability versus porosity. Although this substantially improved the coefficient of determination, no spatial information of the pore space was considered, because DIA parameters were obtained from two-dimensional analyses. Here, we propose a methodology to link local and global pore-space parameters, obtained from three-dimensional (3-D) images, to experimental physical properties of Carbonate Rocks to improve P-wave velocity and permeability predictions. Results show that applying a combination of porosity, microporosity, and 3-D geometrical parameters to P-wave velocity significantly improves the adjusted coefficient of determination from 0.490 to 0.962. A substantial improvement is also observed in permeability prediction (from 0.668 to 0.948). Both results can be interpreted to reflect a pore geometrical control and pore size control on P-wave velocity and permeability.
-
relationship between the consolidation parameter porosity and aspect ratio in microporous Carbonate Rocks
Journal of Applied Geophysics, 2015Co-Authors: Marco Ceia, Roseane M Missagia, Irineu Lima Neto, Nathaly Lopes ArchilhaAbstract:Abstract The estimation of dry bulk modulus is required for the successful application of the Biot–Gassmann theory to forecast fluid changes within a reservoir. The Pride model is one of the several models described in the literature for predicting the dry elastic moduli of Rocks. However, the accuracy of the Pride model depends on the estimation of the consolidation parameter. In this paper, the consolidation parameter was estimated using the pore stiffness, mineral bulk modulus and porosity. That approach allowed calculating the dry bulk modulus of a set of microporous Carbonate Rocks according to the Pride model and compare those estimates to the results obtained using the elastic velocities. The change in the consolidation parameter over a range of pressures suggests that the relationship between this parameter and the unconfined porosity increases at high effective pressure. Statistical analyses of the distribution of those consolidation parameter values were performed to verify how the effective pressure influences the mean value and variance. Mean pore aspect ratios were estimated using Kuster–Toksoz methodology to establish a relationship with the consolidation parameter and the unconfined porosity. Such relationship also accounts for pressure-dependence within the studied pressure range. Although only 20 samples were analyzed, those studies can contribute to advise the estimation of the consolidation parameter in this type of Carbonate Rocks.
-
relationship between the consolidation parameter and aspect ratio in microporous Carbonate Rocks
76th EAGE Conference and Exhibition 2014, 2014Co-Authors: Marco Ceia, Lima I Neto, Roseane M Missagia, Nathaly Lopes ArchilhaAbstract:The estimation of dry bulk modulus is determinant for the success of the application of Biot-Gassmann theory to forecast fluid changes within a reservoir. The Pride model is one of the various models described in literature for predicting the dry elastic moduli of Rocks. However, that model depends on the consolidation parameter and its appropriate choice implies in the accuracy of that model. In this paper, the consolidation parameter is estimated in microporous Carbonate Rocks. Mean aspect ratios were estimated using Kuster-Toksoz methodology and aided to establish a relationship between the consolidation parameter, the unconfined porosity and the aspect ratio. Those studies can advise the estimation of the consolidation parameter in Carbonate Rocks, especially when compressional and shear velocities are unknown.
-
estimation of the consolidation parameter on microporous Carbonate Rocks
Seg Technical Program Expanded Abstracts, 2013Co-Authors: Marco Ceia, Roseane M Missagia, Irineu Lima Neto, Nathaly Lopes ArchilhaAbstract:Summa ry The estimation of dry bulk modulus is determinant for the success of the application of Biot-Gassmann theory to forecast fluid changes within a reservoir. The Pride model is one of the various models described in literature for predicting the dry elastic moduli of Rocks. However, that model depends on the consolidation parameter and its appropriate choice implies in the accuracy of that model. In this paper, two methods for estimating the consolidation parameter are tested and compared in microporous Carbonate Rocks. The observation of how this parameter changes as pressure increases allowed the proposal of a relationship that relates the consolidation parameter and the unconfined porosity to be used at high effective pressure.
Gustavo M Paulasantos - One of the best experts on this subject based on the ideXlab platform.
-
rare earth elements in the terminal ediacaran bambui group Carbonate Rocks brazil evidence for high seawater alkalinity during rise of early animals
Precambrian Research, 2020Co-Authors: Gustavo M Paulasantos, Sergio Caetanofilho, Jacinta Enzweiler, Margareth Sugano Navarro, Marly Babinski, Cristian Guacaneme, Matheus Kuchenbecker, Humberto L S Reis, Ricardo I F TrindadeAbstract:Abstract Rare earth elements plus yttrium (REY) mass fractions of ancient Carbonate Rocks are used to track changes in chemistry of past seawater. Here we investigate REY patterns in two Carbonate sections from the Ediacaran Bambui Group, Sao Francisco Basin (Brazil), which comprise its two lowermost transgressive-regressive second-order sedimentary sequences. Shale normalised distributions vary with the sequence stratigraphy framework. In the basal 2nd-order sequence, Carbonate samples from the basal sequence transgressive systems tract display light REY (LREY) distributions slightly depleted to enriched that reflect input of freshwater, possibly in a post glacial episode. Upwards, Carbonate Rocks from the early highstand systems tract (EHST) yielded LREY enriched distributions, which progressively turns into LREY shale normalized depleted distributions on samples from the late highstand systems tract (LHST). This portion of the sequence also displays Y positive anomaly in some cases. Carbonate samples from the upper second-order sequence do not display coherent patterns. Ce/Ce* values > 1 in most samples throughout the two sections suggest permanent anoxia of seawater. The REY change from the EHST to LHST in the basal sequence marks an important paleoenvironmental overturn in the basin, with increasing alkalinity in seawater driving REY fractionation and LREY depletion. Confinement of the basin in the inner areas of West Gondwana due the uplift of marginal neoproterozoic orogens probably changed the weathering style of source areas to more congruent, thus delivering a higher ionic influx to a restricted setting, increasing alkalinity during LHST. Cloudina sp. fragments were reported in this stage of the Bambui Group and in Carbonate Rocks with high Sr mass fractions in other West Gondwana basins, supporting the hypothesis that the high alkalinity of seawater during late Ediacaran may have driven the appearance of the first biomineralizing organisms.
Kishore K. Mohanty - One of the best experts on this subject based on the ideXlab platform.
-
asp flooding in tight Carbonate Rocks
Fuel, 2019Co-Authors: Pinaki Ghosh, Himanshu Sharma, Kishore K. MohantyAbstract:Abstract Alkaline-Surfactant-Polymer (ASP) floods can mobilize oil left behind by waterfloods by lowering the interfacial tension. However, conducting such floods in tight Carbonate Rocks presents several challenges, e.g., polymer transport in low permeability Carbonates, presence of divalent ions, geochemical interactions with chemicals and rock surface, pore-scale heterogeneity, and oil-/mixed-wettability. This paper addresses the first three challenges. A systematic study of polymer transport in low permeability Carbonate cores was performed. Shearing of high molecular weight polymers and successive filtration treatment were performed to improve polymer size distribution. Single phase polymer transport experiments were performed in low permeability Carbonate Rocks, and optimum pretreatment method was developed. Surfactant phase behavior and aqueous stability experiments were performed to develop ultralow tension ASP and SP formulations with a reservoir crude oil. ASP and SP corefloods were performed in oil-wet low permeability limestone Rocks. The oil recovery, pressure drop, effluent ionic composition, effluent viscosity and effluent surfactant concentrations were measured. PHREEQC simulations were performed to understand geochemical reactions during ASP floods. The polymer treatment procedure was able to successfully transport polymer through low permeability Edwards Yellow limestone cores, but not through Texas Cream limestone due to differences in their pore structures. It was found that polymer hydrodynamic radius must be smaller than the pore throat radii of the rock for successful polymer transport. Therefore, mercury porosimetry data of the porous medium is critical for polymer selection, especially in case of low permeability Rocks. Tertiary ASP floods resulted in improving the cumulative oil recovery to 77–87% OOIP, whereas SP flood improved the cumulative oil recovery to 85% in an outcrop core. Surfactant retentions during ASP and SP corefloods were found to be 0.4 mg/g-rock and 0.3 mg/g-rock, respectively, in outcrop cores.
-
Wettability Altering Secondary Oil Recovery in Carbonate Rocks
Energy & Fuels, 2011Co-Authors: Kshitij Mohan, Robin Gupta, Kishore K. MohantyAbstract:Carbonate Rocks tend to be oil-wet, leading to lower oil relative permeability and lower oil recovery in the life of a waterflood, which is about 3 pore volume (PV) injection. The goal of this work...
Marly Babinski - One of the best experts on this subject based on the ideXlab platform.
-
rare earth elements in the terminal ediacaran bambui group Carbonate Rocks brazil evidence for high seawater alkalinity during rise of early animals
Precambrian Research, 2020Co-Authors: Gustavo M Paulasantos, Sergio Caetanofilho, Jacinta Enzweiler, Margareth Sugano Navarro, Marly Babinski, Cristian Guacaneme, Matheus Kuchenbecker, Humberto L S Reis, Ricardo I F TrindadeAbstract:Abstract Rare earth elements plus yttrium (REY) mass fractions of ancient Carbonate Rocks are used to track changes in chemistry of past seawater. Here we investigate REY patterns in two Carbonate sections from the Ediacaran Bambui Group, Sao Francisco Basin (Brazil), which comprise its two lowermost transgressive-regressive second-order sedimentary sequences. Shale normalised distributions vary with the sequence stratigraphy framework. In the basal 2nd-order sequence, Carbonate samples from the basal sequence transgressive systems tract display light REY (LREY) distributions slightly depleted to enriched that reflect input of freshwater, possibly in a post glacial episode. Upwards, Carbonate Rocks from the early highstand systems tract (EHST) yielded LREY enriched distributions, which progressively turns into LREY shale normalized depleted distributions on samples from the late highstand systems tract (LHST). This portion of the sequence also displays Y positive anomaly in some cases. Carbonate samples from the upper second-order sequence do not display coherent patterns. Ce/Ce* values > 1 in most samples throughout the two sections suggest permanent anoxia of seawater. The REY change from the EHST to LHST in the basal sequence marks an important paleoenvironmental overturn in the basin, with increasing alkalinity in seawater driving REY fractionation and LREY depletion. Confinement of the basin in the inner areas of West Gondwana due the uplift of marginal neoproterozoic orogens probably changed the weathering style of source areas to more congruent, thus delivering a higher ionic influx to a restricted setting, increasing alkalinity during LHST. Cloudina sp. fragments were reported in this stage of the Bambui Group and in Carbonate Rocks with high Sr mass fractions in other West Gondwana basins, supporting the hypothesis that the high alkalinity of seawater during late Ediacaran may have driven the appearance of the first biomineralizing organisms.