1887

Abstract

Summary

Characterizing the pore structure of a reservoir using low field nuclear magnetic resonance (NMR) has been used extensively during the last decades by geologists and petrophysicists, providing important information for a more accurate evaluation of well producibility (e.g. porosity, permeability, pore-size distributions, saturation) ( ). Usually, the NMR transverse relaxation time (T2) decay is interpreted in terms of pore-sizes by the constant known of surface relaxivity (ρs), ( ). In clean and porous sandstones, the pore radius estimations using NMR can be successfully calculated (e.g. ), however in heterogeneous rocks with different compositions and magnetic susceptibilities, this relation produces a wide range of relaxivity ( ; Jácomo et al., 2020).

The Barra Velha Formation is the main pre-salt carbonate reservoir in Santos Basin (Southeast Brazil) and is highly studied. However, only some NMR studies investigated these carbonates, and none investigated the relaxivity ( ). The objective of this work is to understand which factors can be a source for the range of relaxivity results. To accomplish this, we use petrographic, core routine analysis, NMR special petrophysics measurements, and X-ray microcomputed tomography (mCT) to calculate the relaxivity in Brazilian pre-salt carbonates.

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/content/papers/10.3997/2214-4609.202310384
2023-06-05
2026-02-15

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References

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/content/papers/10.3997/2214-4609.202310384
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Determining NMR Transverse Surface Relaxivity Using MicroCT Scanning for Pore Structure Evaluation in Pre-Salt Brazilian Carbonates
Conference Proceedings 2023, 1 (2023); https://doi.org/10.3997/2214-4609.202310384
/content/papers/10.3997/2214-4609.202310384
/content/papers/10.3997/2214-4609.202310384
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