Research Article
Comprehensive Evaluation of the Hydrocarbon Preservation Conditions in the Complex Tectonic Area of the Southwestern Sichuan Basin, China
Table 3
The comprehensive evaluation system for hydrocarbon preservation conditions of the Upper Permian formations.
| | Evaluation parameters | Evaluation results | | Class I | Class II | Class III |
| | Distance to dominating fault (km) | >4.0 | 2.0-4.0 | <2.0 | | Fault development | Less distributed, small fault distance, and few cut-through horizons | Widely distributed, medium fault distance, and more cut-through horizons. | Widely distributed, large fault distance, multiple cut-through layers, and deep cut layers | | Outcrops | Jurassic–Triassic | Permian-Devonian | Silurian-Sinian | | Mineralization (g·L-1) | >50 | 10-50 | <10 | | Water type | CaCl2 is the dominant type, followed by MgCl2 | MgCl2, Na2SO4 | NaHCO3, Na2SO4 | | Caprock | Large thickness and good sealing | Moderately sealed | Small thickness and severe erosion |
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