What is primary porosity?
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Primary porosity refers to the inherent pore spaces within a rock that are formed during the initial sediment deposition process, before any post-genetic alterations occur. It is a crucial parameter influencing reservoir quality and productivity in hydrocarbon exploration . Factors affecting primary porosity include grain shape, size, sorting, packing, and orientation in sandstones . Understanding primary porosity is essential for predicting reservoir quality, as it directly impacts permeability and fluid flow within the rock matrix . In sandstones, primary porosity is influenced by various attributes like roundness, flatness, elongation, and grain packing texture, with grain-size distribution playing a significant role . The development of primary porosity in igneous rocks is also discussed, highlighting its importance in basement formations and its time- and scale-dependent nature .
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34 Citations | Primary porosity in igneous rocks is the initial pore space formed during magma cooling, classified into diffusive (Class D) and flow (Class F) features, influencing permeability and transport properties. |
Open access 01 Jan 2004 | Primary porosity is inherent inter-granular porosity in rock formed during lithogenesis, distinct from secondary porosity created post-genesis by processes like fracturing or dissolution. |
| Primary porosity is formed during sediment deposition, influenced by factors like grain shape, size, and packing. It is a key aspect of reservoir characterization and affects permeability. | |
1 Citations | Primary porosity in sandstone is crucial for predicting reservoir quality. It is influenced by grain shape, grain-size distribution, and packing texture, rather than mean grain size. |
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