Data from: Characterization of fluid occurrence states in Shale reservoirs: Centrifugal-nuclear magnetic resonance experimental analysis
Data files
Aug 05, 2025 version files 215.88 KB
-
Raw_data.opju
211.76 KB
-
README.md
4.12 KB
Abstract
The occurrence states of fluids in shale reservoirs directly influence the resource assessment of shale gas, reservoir permeability, selection of development technologies, and economic benefits. Accurate analysis of fluid occurrence states is a key foundation for the efficient exploration and development of shale gas. To comprehensively elucidate the fluid distribution characteristics within shale pores, this study integrates centrifugation-nuclear magnetic resonance (NMR) experiments with stepwise thermal drying and methane adsorption analyses. By examining the NMR T₂ spectra of shale samples under varying centrifugal speeds, the distinction between movable and bound fluids is established, clarifying the influence of pore structure on fluid occurrence. Quantitative relationships between pore size and adsorbed/free gas are further investigated through methane adsorption experiments. Results demonstrate that centrifugation progressively removes water from macropores and microfractures, leaving residual water mainly confined to micropores. The stepwise thermal drying method efficiently differentiates movable water, capillary-bound water, and clay-bound water. Integrating NMR analysis with methane adsorption reveals a significant impact of pore size on fluid occurrence: micropores predominantly store adsorbed gas, whereas macropores mainly contain free gas. These findings provide a theoretical basis for shale gas development and furnish essential data for optimizing exploration and production techniques.
Dataset DOI: 10.5061/dryad.6t1g1jxbj
Description of the data and file structure
This document provides detailed information about the raw data underlying Figure 1 to 5 from the study "Characterization of Fluid Occurrence States in Shale Reservoirs: Centrifugal-Nuclear Magnetic Resonance Experimental Analysis". The data is derived from experimental analyses, including centrifugation-NMR, porosity measurements, and methane adsorption tests on shale samples. All data is structured to support reproducibility and further research.
The experimental principles and detailed operational procedures have been comprehensively described in the article. This document solely contains the experimental data for verification of results or direct use by all parties.
Files and variables
File: Raw_data.opju
Description: The subfolder "Folder1" under "Raw_data" contains Figure 1, 2, 3, 4, 5, and 6.
Figure 1: NMR T2 Spectra of Saturated Water and Centrifugal Experiments
Figure 1 illustrates the evolution of NMR T2 spectra for four shale samples under water-saturated conditions and varying centrifugal speeds (4000–12000 rpm).
Figure 1 includes 1a, 1b, 1c, 1d.
The x-axis represents the nuclear magnetic resonance T2 spectrum (ms), with data in log10 scale. The y-axis represents the signal intensity (au), with data in linear scale. It also includes the description of each set of data (Water saturation, The speed of the centrifuge).
Figure 2: Changes in NMR Porosity at Different Centrifugal Speeds
Figure 2 shows NMR-derived porosity changes for shale samples across centrifugal speeds.
Figure 2 includes Sheet1.
The x-axis represents the Centrifugation rate (rpm). The y-axis represents the Magnetic porosity (%). It also includes the description of each set of data (Sample Number).
Figure 3: NMR T2 Spectra After Centrifugal Experiments
Figure 3 compares NMR T2 spectra for core plugs and crushed samples after centrifugation, emphasizing pore-type effects.
Figure 3 includes 3a, 3b, 3c, 3d, 3e, 3f.
The x-axis represents the nuclear magnetic resonance T2 spectrum (ms), with data in log10 scale. The y-axis represents the signal intensity (au), with data in linear scale. It also includes the description of each set of data (The speed of the centrifuge).
Figure 4: Methane Adsorption NMR T2 Spectra
Figure 4 displays NMR T2 spectra for methane adsorption under pressures (2.80–14.62 MPa), featuring a three-peak distribution.
Figure 4 includes 4a, 4b, 4c, 4d.
The x-axis represents the nuclear magnetic resonance T2 spectrum (ms), with data in log10 scale. The y-axis represents the signal intensity (au), with data in linear scale. It also includes the description of each set of data (Pressure values).
Figure 5: Methane Mass vs. Pressure Relationship
Figure 5 quantifies methane mass per peak vs. pressure, revealing occurrence states.
Figure 5 includes 5-1, 5-2, 5-3.
The x-axis represents the Pressure (Mpa), with data in linear scale. The y-axis represents the First peak methane mass (g), with data in linear scale.
Figure 6: Relationship between pore volume and NMR signal intensity for each peak in the methane adsorption T2 spectra after fractal analysis
Figure 6 shows the correlation analysis between the porosity contributions of various pore types and the NMR signal intensities of each peak in methane adsorption T₂ spectra.
Figure 6 includes 6-1, 6-2, 6-3.
The x-axis represents the Micro-pore porosity (%), with data in linear scale. The y-axis represents the First peak area semaphore (au), with data in linear scale.
Code/software
The file can be viewed using Origin software (any version).
OriginLab - Origin and OriginPro - Data Analysis and Graphing Software
Access information
Other publicly accessible locations of the data:
- NA
Data was derived from the following sources:
- NA