Vuggy carbonate rocks

A DOUBLE-POROSITY POROELASTIC MODEL TO RELATE P-WAVE ATTENUATION TO FLUID FLOW IN VUGGY CARBONATE ROCK... 

FIGURE 2.21 Permeability (air) versus porosity for various particle-size groups in non-vuggy carbonate rocks. Lucia (1983, 1999, 2007). 

Class II deposits in reservoirs made up of consolidated terrigenous sediments sands not running reservoirs lying at depths from 800 to 1500 m Class III deposits in reservoirs made up of carbonate rocks with complex porosities of fracture, cavern, and and vuggy types. 

Following the rock-fabric classification, Jennings and Lucia (2001) developed a systematic plot presentation for non-vuggy carbonates and subdivided limestone and dolomite into three classes with rock-fabric numbers. The generalized carbonate permeability model provides a relationship between permeability, interparticle porosity, and rock-fabric number ... 

In carbonate rocks, the time-average equatimi works for most intergranular, interparticle porosities this pore distribution is somewhat similar to sandstone. In vuggy carbonates, the slowness is dominated by primary intergranular, interparticle porosity, and the resulting porosity tends, in some cases, to be underestimated by the secondary porosity (Asquith and Krygowski, 2004). 

Figure 8.13 shows the results with a separation of the three carbonate rock types. The vuggy Wetterstein dolomite is characterized by high formation factors. In a forthcoming paper (MiiUer-Huber et al., 2015), a comparison with model calculations demonstrates the effect of pore geometry, expressed by the ratio of pore-body and pore-throat radius (see Section 8.4.5). 

MilUer-Huber, E., 2013. New concepts for understanding the effects of complex pore structures on petrophysical properties of carbonate rocks. Dr. thesis, Montanuniversitat Leoben. MilUer-Huber, E., Schdn, J., 2013a. A modified archie relationship—a novel approach to evaluate carbonate reservoirs with regard to fracture and isolated vuggy porosity for Sw = 1. In Paper IPTC 16695 Presented at the 6th International Petroleum Technology Conference, Beijing, China, 26-28 March. http //dx.doi.org/10.2523/16695-MS. 

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