Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations
Perhaps as much as 50% of the oil-in-place in carbonate formations around the world is locked away in the easy to bypass microporosity. If some of this oil is unlocked by the improved recovery processes focused on tight carbonate formations, the world may gain a major source of lower-rate power over...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-02-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/15/3/1243 |
| _version_ | 1797487926150430720 |
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| author | Tadeusz W. Patzek Ahmed M. Saad Ahmed Hassan |
| author_facet | Tadeusz W. Patzek Ahmed M. Saad Ahmed Hassan |
| author_sort | Tadeusz W. Patzek |
| collection | DOAJ |
| description | Perhaps as much as 50% of the oil-in-place in carbonate formations around the world is locked away in the easy to bypass microporosity. If some of this oil is unlocked by the improved recovery processes focused on tight carbonate formations, the world may gain a major source of lower-rate power over several decades. Here, we overview the Arab D formation in the largest oil field on earth, the Ghawar. We investigate the occurrence of microporosity of different origins and sizes using scanning electron microscopy (SEM) and pore casting techniques. Then, we present a robust calculation of the probability of invasion and oil saturation distribution in the nested micropores using mercury injection capillary pressure data available in the literature. We show that large portions of the micropores in Arab D formation would have been bypassed during primary drainage unless the invading crude oil ganglia were sufficiently long. We also show that, under prevailing conditions of primary drainage of the strongly water-wet Arab formations in the Ghawar, the microporosity there was invaded and the porosity-weighted initial oil saturations of 60–85% are expected. Considering the asphaltenic nature of crude oil in the Ghawar, we expect the invaded portions of the pores to turn mixed-wet, thus becoming inaccessible to waterflooding until further measures are taken to modify the system’s surface chemistry and/or create substantial local pore pressure gradients. |
| first_indexed | 2024-03-09T23:54:47Z |
| format | Article |
| id | doaj.art-a8fcf28ea28e41ea8564a0a58f9c8cdb |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-09T23:54:47Z |
| publishDate | 2022-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-a8fcf28ea28e41ea8564a0a58f9c8cdb2023-11-23T16:27:40ZengMDPI AGEnergies1996-10732022-02-01153124310.3390/en15031243Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab FormationsTadeusz W. Patzek0Ahmed M. Saad1Ahmed Hassan2The Ali I. Al-Naimi Petroleum Engineering Research Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi ArabiaThe Ali I. Al-Naimi Petroleum Engineering Research Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi ArabiaThe Ali I. Al-Naimi Petroleum Engineering Research Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi ArabiaPerhaps as much as 50% of the oil-in-place in carbonate formations around the world is locked away in the easy to bypass microporosity. If some of this oil is unlocked by the improved recovery processes focused on tight carbonate formations, the world may gain a major source of lower-rate power over several decades. Here, we overview the Arab D formation in the largest oil field on earth, the Ghawar. We investigate the occurrence of microporosity of different origins and sizes using scanning electron microscopy (SEM) and pore casting techniques. Then, we present a robust calculation of the probability of invasion and oil saturation distribution in the nested micropores using mercury injection capillary pressure data available in the literature. We show that large portions of the micropores in Arab D formation would have been bypassed during primary drainage unless the invading crude oil ganglia were sufficiently long. We also show that, under prevailing conditions of primary drainage of the strongly water-wet Arab formations in the Ghawar, the microporosity there was invaded and the porosity-weighted initial oil saturations of 60–85% are expected. Considering the asphaltenic nature of crude oil in the Ghawar, we expect the invaded portions of the pores to turn mixed-wet, thus becoming inaccessible to waterflooding until further measures are taken to modify the system’s surface chemistry and/or create substantial local pore pressure gradients.https://www.mdpi.com/1996-1073/15/3/1243microporositymultimodal porosityprimary drainagecapillary invasionmixed wettabilityIOR |
| spellingShingle | Tadeusz W. Patzek Ahmed M. Saad Ahmed Hassan Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations Energies microporosity multimodal porosity primary drainage capillary invasion mixed wettability IOR |
| title | Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations |
| title_full | Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations |
| title_fullStr | Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations |
| title_full_unstemmed | Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations |
| title_short | Multimodal Carbonates: Distribution of Oil Saturation in the Microporous Regions of Arab Formations |
| title_sort | multimodal carbonates distribution of oil saturation in the microporous regions of arab formations |
| topic | microporosity multimodal porosity primary drainage capillary invasion mixed wettability IOR |
| url | https://www.mdpi.com/1996-1073/15/3/1243 |
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