In-situ stress dependence of wave velocities in reservoir and overburden rocks

Holt, R.M.; Nes, Olav-Magnar; Fjær, Erling

doi:10.1190/1.2149650

Cited by 51 publications

(29 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The presence of cement also implies that cracks may be formed, and hence the stress sensitivity may be larger. Also for field shale cores, we tend to observe that the stress sensitivity is almost absent for poorly consolidated rocks, while it is much larger and significant for the more competent rocks (Holt et al, 2005).…”

Section: Discussionmentioning

confidence: 95%

Stress-induced versus lithological anisotropy in compacted claystones and soft shales

et al. 2011

Self Cite

View full text Add to dashboard Cite

Shales are anisotropic. Most definitions of shale in-corporate this attribute, either by referring to fissility and existence of cleavage planes, or to anisotropic texture resulting in anisotropy of physical properties on many length scales. Definitions of shale scatter though; some focus on a high content of clay minerals as characteristic of a shale, while others consider a large amount of fine grains (< 2μm) as sufficient. In a rock mechanical context, it is natural to define shale as a rock in which clay minerals constitute the load-bearing framework. This means that “gas shales” in oil-field terminology are, strictly speaking, not shales according to a geological or a geomechanical perspective. Still, these materials have a lot in common with classically defined shales (e.g., low permeability) and anisotropy.

show abstract

Section: Discussionmentioning

confidence: 95%

Stress-induced versus lithological anisotropy in compacted claystones and soft shales

et al. 2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…Specifically, these processes can induce the creation of cracks which will increase the stress sensitivity of the cores as compared to the intact formation (Holt et al, 2000(Holt et al, , 2005.…”

Section: Methodsmentioning

confidence: 99%

Investigation of core data reliability to support time‐lapse interpretation in Campos Basin, Brazil

Grochau

Gurevich

2007

SEG Technical Program Expanded Abstracts 2007

View full text Add to dashboard Cite

In order to calibrate time-lapse quantitative interpretation, it is crucial to analyze saturation and pressure effects on seismic velocities. While the former is adequately modeled using Gassmann equations, the latter is mainly obtained by laboratory measurements, which can be affected by core damage. We investigate the magnitude of this effect on compressional wave velocities by comparing laboratory experiments and log measurements. We use Gassmann fluid substitution to obtain low-frequency saturated velocities from dry core measurements (thus mitigating the dispersion effects) taken at reservoir pressure. The analysis is performed for an unusual densely cored well from which 43 cores were extracted over a 45 meters thick turbidite reservoir. Comparison of these computed velocities with the sonic log measurements shows very good agreement. This confirms that for this particular region the effect of core damage on M. Grochau and B. Gurevich 2 ultrasonic measurements is below the measurement error. Consequently stress sensitivity of elastic properties as obtained from ultrasonic measurements is adequate for quantitative interpretation of time-lapse seismic data in this area.

show abstract

“…Since dynamic as well as static Young's moduli increase with depth (e.g. Carlson and Gangi 1985;Holt et al 2005), Young's modulus at reservoir depth should therefore be higher than at the surface. Thus, Young's modulus at reservoir depth has been highly underestimated.…”

Section: Rock Mechanical Propertiesmentioning

confidence: 99%

Predictability of properties of a fractured geothermal reservoir: the opportunities and limitations of an outcrop analogue study

et al. 2017

View full text Add to dashboard Cite

In-situ stress dependence of wave velocities in reservoir and overburden rocks

Cited by 51 publications

References 0 publications

Stress-induced versus lithological anisotropy in compacted claystones and soft shales

Stress-induced versus lithological anisotropy in compacted claystones and soft shales

Investigation of core data reliability to support time‐lapse interpretation in Campos Basin, Brazil

Predictability of properties of a fractured geothermal reservoir: the opportunities and limitations of an outcrop analogue study

Contact Info

Product

Resources

About