Low-Field Nuclear Magnetic Resonance Characterization of Carbonate and Sandstone Reservoirs From Rock Spring Uplift of Wyoming
Abstract Laboratory measurements including gas (N 2 ) porosity and permeability, time‐domain nuclear magnetic resonance, thin section, and scanning electron microscopy analysis were conducted to obtain petrographical and petrophysical descriptions of the Weber Sandstone and Madison Limestone at the Rock Spring Uplift, a potential carbon dioxide storage site in Southwestern Wyoming. The relationships between pore structures, such as pore geometry, pore‐size distribution, pore network, and porosity/permeability are investigated. First, using thin sections combined with scanning electron microscopy for pore structures description, all samples are described in detail from the geological, petrographysical, and diagenetic viewpoint. Results show that within the Madison Limestone, pore types include intercrystalline, vuggy, moldic, or mixed (combination of all other pore types). Both moldic and vuggy pore types are associated with samples of high porosity and permeability. Nuclear magnetic resonance relaxation time distributions show either bimodal or multimodal distributions. Large relaxation time components are associated with samples with large pores, whereas small components are dominated by small pores. The T 2 geometric mean correlates well with gas permeability. Additionally, short‐time diffusion coefficients (D) were measured by pulsed field gradient method using a series of gradient strengths. We found that diffusion coefficient distributions correlate with the corresponding T 2 distributions for macropores. By comparing the dominant peak position of T 2 distributions and their corresponding diffusion coefficient distributions, we predicted the surface relaxivity of different rock types. We found that surface relaxivities of Weber Sandstone samples can be well predicted, while for Madison Limestone samples, surface relaxivities are overestimated due to diffusive pore coupling effect.
- Research Organization:
- Univ. of Wyoming, Laramie, WY (United States)
- Sponsoring Organization:
- USDOE Office of Fossil Energy (FE); USDOE
- Grant/Contract Number:
- FE0023328; DE547 FE0023328
- OSTI ID:
- 1539754
- Alternate ID(s):
- OSTI ID: 1470598
- Journal Information:
- Journal of Geophysical Research. Solid Earth, Vol. 123, Issue 9; ISSN 2169-9313
- Publisher:
- American Geophysical UnionCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Capillary Pressure Curve Determination Based on a 2‐D Cross‐Section Analysis Via Fractal Geometry: A Bridge Between 2‐D and 3‐D Pore Structure of Porous Media
|
journal | March 2019 |
Similar Records
A rock physics and seismic reservoir characterization study of the Rock Springs Uplift, a carbon dioxide sequestration site in Southwestern Wyoming
Carbon Dioxide Sealing Capacity: Textural or Compositional Controls? (Final Scientific/Technical Report)