Reservoir Characterization and Pore Type Systems of Carbonate Low Resistivity Pay in Persian Gulf
| Autor: | Davod Jahani, Bita Arbab, Bahram Movahed |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
020209 energy
Mineralogy 02 engineering and technology Texture (geology) Grain size chemistry.chemical_compound chemistry Electrical resistivity and conductivity 0202 electrical engineering electronic engineering information engineering Reservoir modeling Kaolinite Carbonate Clay minerals Porosity Geology |
| Zdroj: | Open Journal of Geology. :859-870 |
| ISSN: | 2161-7589 2161-7570 |
| DOI: | 10.4236/ojg.2017.76059 |
| Popis: | The main focus of study is to characterize lower and upper cretaceous carbonate deposits with Low Resistivity Pay, in Persian Gulf. Four oil reservoirs in the Cretaceous including the Zubair, Buwaib, Shuaiba and Khatiyah Formations of Southern fields have been analyzed. Here is a look at that to determine main factors on decreasing resistivity in pay zone. In some intervals resistivity responses reach less than 6 to 1 ohm·m. Significant hydrocarbon accumulations are “hidden” in low resistivity Pay zone, (LRPZ). LRPZ reservoirs have been found in some formations in Persian Gulf. Causes of LRPZ reservoirs on the basis of experimental analysis include clay-coated grains, carbonate with interstitial dispersed clay. On the other side Smectite and Kaolinite of main clays types have high CEC and greater impact on lowering resistivity. Micritization and Pyritization of digenetic process have noticeable impact on LRPZ. It is mentioned that Lonoy method applied to address pore throat sizes which contain Inter crystalline porosity, Chalky Limestone, Mudstone micro porosity. Pore systems are classified at class 2 and 3 Lucia and pore size varies from 0.5 to 4 micron. NMR Core and Log results show different pore size distribution. NMR core and MRIL results explain that decreasing of resistivity in pay zone is related to texture and grain size variation not being existence of moved water. Irreducible water estimate for this reservoir was between 30% and 50%. T2 cut off estimates, for defining irreducible water saturation, 115 ms. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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