On Estimating Irreducible Water Saturation in Tight Formations Using Nuclear Magnetic Resonance Relaxometry

2018 ◽  
Author(s):  
Razieh Solatpour ◽  
Jonathan Luke Bryan ◽  
Apostolos Kantzas
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Water Saturation ◽  
Irreducible Water Saturation ◽  
Nuclear Magnetic Resonance Relaxometry ◽  
Tight Formations ◽  
Nuclear Magnetic

Determination of nuclear magnetic resonance T2 cutoff value based on multifractal theory — An application in sandstone with complex pore structure

Geophysics ◽  
2015 ◽  
Vol 80 (1) ◽  
pp. D11-D21 ◽  
Author(s):  
Xinmin Ge ◽  
Yiren Fan ◽  
Xuejuan Zhu ◽  
Yiguo Chen ◽  
Runze Li
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Pore Structure ◽  
Water Saturation ◽  
Influential Factors ◽  
Structure Characterization ◽  
Cutoff Value ◽  
Irreducible Water Saturation ◽  
Multifractal Theory ◽  
Nuclear Magnetic

The cutoff value of nuclear magnetic resonance (NMR) transversal relaxation time [Formula: see text] is vital for pore structure characterization, permeability prediction, and irreducible water saturation calculation. Conventional default values often lead to inaccurate results for rocks with complex pore structure. Based on NMR experiments and multifractal theory, we have developed an effective statistical method to predict [Formula: see text] cutoff values without other petrophysical information. The method is based on multifractal theory to analyze the NMR [Formula: see text] spectrum with the assumption that the [Formula: see text] spectrum is an indicator of pore size distribution. Multifractal parameters, such as multifractal dimension, singularity strength, and mass exponent, are calculated to investigate the multifractal behavior of [Formula: see text] spectrum via NMR experiments and a dyadic scaling-down algorithm. To obtain the optimal [Formula: see text] cutoff value, the rotation speed and time of centrifugation are enlarged increasingly to optimal centrifugal state. A predicating model for [Formula: see text] cutoff value based on multiple linear regressions of multifractal parameters was proposed after studying the influential factors. On the basis of the multifractal analysis of NMR [Formula: see text] spectrum, a reasonable predication model for [Formula: see text] cutoff value was rendered. Upon testing, the predicted results were highly consistent with the experimental results.

Irreducible Water Saturation Measurement of Volcanic Rocks Using Nuclear Magnetic Resonance

2011 ◽  
Vol 346 ◽  
pp. 852-857
Author(s):  
Yu Zhou ◽  
He Kun Guo ◽  
Guo Qi Wei
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Water Saturation ◽  
Volcanic Rocks ◽  
New Method ◽  
Fundamental Parameters ◽  
Irreducible Water Saturation ◽  
Key Factor ◽  
Structure Complexity ◽  
Nuclear Magnetic

Irreducible water saturation is one of the fundamental parameters in characterizing reservoir formations, and determined as the key factor in reserve calculation and fluid type identification. Measurement on whole core must be taken to analyze irreducible water saturation of volcanic rocks as a result of lithological diversity, porous structure complexity and strong heterogeneity. A new testing method for whole core is proposed by combining Nuclear Magnetic Resonance and centrifugal tests. This new method measures irreducible water saturation using T2 spectrum of whole core demarcated by T2 cutoff measured on 25mm or 38mm diameter core samples which drilled from the whole core. The new method solved the size and shape restricts, long test cycles and viscous fingering defects of conventional methods. According to the comparison with conventional method, the results of the new method coincide well on homogeneous rocks, and are more accuracy with fractured samples.

Water dynamics in eggs by means of Nuclear Magnetic Resonance relaxometry

2021 ◽  
Vol 327 ◽  
pp. 106976
Author(s):  
Danuta Kruk ◽  
Małgorzata Florek-Wojciechowska ◽  
Mecit Oztop ◽  
Esmanur Ilhan ◽  
Zbigniew Wieczorek
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Water Dynamics ◽  
Nuclear Magnetic Resonance Relaxometry ◽  
Nuclear Magnetic

scholarly journals Preliminary magnetic resonance relaxometric analysis of Fricke gel dosimeters produced with polyvinyl alcohol and glutaraldehyde

2017 ◽  
Vol 32 (3) ◽  
pp. 242-249 ◽  
Author(s):  
Salvatore Gallo ◽  
Giorgio Collura ◽  
Giuseppina Iacoviello ◽  
Anna Longo ◽  
Luigi Tranchina ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Polyvinyl Alcohol ◽  
Dose Range ◽  
Relaxation Times ◽  
Ion Concentration ◽  
Nuclear Magnetic Resonance Relaxometry ◽  
New Formulation ◽  
Nuclear Magnetic

This work describes the preliminary analysis of Fricke gels dosimeters characterized by a new formulation making use of a matrix of polyvinyl alcohol cross-linked by adding glutaraldehyde and analyzed by means of nuclear magnetic resonance relaxometry. In previous optical studies, these gels have shown promising dosimetric features in terms of photon sensitivity and low diffusion of ferric ions produced after irradiation. In this work, we used a portable nuclear magnetic resonance relaxometer to measure the relaxation times (which are important for dosimetric applications) of these gel materials. For this purpose, we performed a study for optimizing the acquisition parameters with a nuclear magnetic resonance relaxometer. Gel samples were exposed to clinical 6 MV photons in the dose range between 0 and 20 Gy. Nuclear magnetic resonance relaxometry measurements were per- formed and the sensitivity to photon beams was measured for various values of the Fe2+ ion concentration. The analyses pointed out that the MR signal increases as the Fe2+ content in- creases and the increase is about 75 % when the concentration of Fe2+ ions is increased from 0.5 mM to 2.5 mM. Furthermore, the sensitivity improvement achieved with increasing the Fe2+ concentration is about 60 %. This paper shows that the portable nuclear magnetic resonance relaxometer used for analysis of porous materials can be used for characterization of these dosimetric gels and this study can be considered as the first step for the characterization of these dosimeters which in future could be used for 3-D dose mapping in clinical applications.

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