In recent years, several deep-water gas fields of Yinggehai Formation have been discovered in ultra-deep water area of Qiongdongnan Basin, showing a broad exploration prospect. However, the reservoir physical property prediction of the Member 2 of Neogene Yinggehai Formation have become increasingly prominent which seriously restricts the further exploration of oil and gas. Based on the regional geological data summarized by predecessors, combined with core, logging and three-dimensional seismic data, the third-order sequence framework of the Member 2 of Neogene Yinggehai Formation is established, and the provenance systems in the sequence framework and the sedimentary characteristics of gravity flow under its control are comprehensively analyzed. The results show that gravity flow sedimentary system mainly developed in Ⅱ2-ygh2c and Ⅱ2-ygh2b, and include three major provenance systems which are the south, the north and the axis. Different rovenance systems control the spatial distribution and sedimentary characteristics of gravity flow reservoirs. (1)The submarine canyons controlled by the south provenance are mainly filled by abyssal mudstone, while the canyons controlled by the north provenance are mainly filled with thick turbidite channel sandstone with fine porosity and permeability, which is a good reservoir. (2) The flood plain deposit affected by axial provenance can also be a good oil and gas reservoir because of its good physical properties. (3) The submarine fans controlled by the south provenance is characterized by thin sandstone with fine grain size and high argillaceous content. While the submarine canyons and fans controlled by the north and the axis provenance formed large scale sandstone with big thickness, coarse grain size and good reservoir physical properties, which are the most important high-quality gas-producing reservoirs of deep water area.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |