The characteristics and controlling factors of glutenite reservoirs in the Permian Upper Urho Formation, southern Zhongguai Rise, Junggar Basin, NW China

Abstract

The southern Zhongguai Rise, the petroliferous zones in northwestern Junggar Basin, is among the most significant sedimentary basins in China because of its abundant petroleum reserves. The reservoir characteristics and their responses to controlling factors have been complex in the Permian Upper Urho Formation. A systematic investigation has been conducted based on integrated analysis of seismic volumes, wireline logs, mud logs, cores, thin sections, SEM, grain size data, porosity‐permeability data, and mercury injection test results. The results indicate that the Upper Urho Formation consists of five types of lithology (glutenite, coarse‐grained sandstone, medium‐grained sandstone, fine‐grained sandstone, and siltstone). Furthermore, the detrital composition in Upper Urho Formation is predominantly composed of debris (mainly volcanic rocks), with relatively less contents of quartz and feldspar. The cement is dominated by calcite, laumontite, and siliceous. In addition, the reservoir space in Upper Urho Formation includes intergranular pore, intragranular pore, dissolution pore, and microfracture. The intergranular pore and dissolution pore comprise the main reservoirs. The reservoirs in Upper Urho Formation are characterized by micro‐fine pore‐throat and low‐porosity permeability. Diagenesis along with sedimentary facies exerts the controls on the reservoir heterogeneity and physical properties.

Development characteristics of deepwater gravity flows and tight sandstone reservoir characteristics in Chang 6 in the Huaqing area, Ordos Basin, China

“…The supply from the provenance area affects the thickness and spatial distribution of the reservoir, and the lithology of the provenance determines the type of rock in the reservoir and the size of the storage space that can be formed. Sedimentology affects reservoir petrology and reservoir distribution (Chen et al, 2022; Yang et al, 2021). Diagenesis directly controls the development of pore throats in reservoirs (Zhang et al, 2021).…”

Fracturing parameter optimization technology for highly deviated wells in complex lithologic reservoirs

“…Exploration in the study area began in the 1980 s, and the Fengcheng Formation (P 1 f) of the Marbei slope (Pf) was located in the Xiazijie nosedive zone during both the Jurassic and Cretaceous orogenic periods, and present-day tectonics suggest that the area is still nosedive at present (Ma et al, 2022;Chen et al, 2022;Shi et al, 2022;Lu et al, 2023). The development of two large-scale retrograde fractures is the main through-origin fracture in this area, and the large-scale fractures are accompanied by microfractures around them (Xiao et al, 2021).…”

“…The main stratigraphic strata drilled from top to bottom in the study area are the Cretaceous Tugulu Group, Jurassic Qigu Formation, Toutunhe Formation, Xishanyao Formation, Sanguohe Formation, Badawan Formation, Triassic Baikaitan Formation, Karamay Formation, Baikouquan Formation, Permian Upper Urho Formation, Lower Urho Formation, Xazijie Formation, Fencheng Formation, and Jiamuhe Formation. Among them, there is an unconformable contact between the Cretaceous and Jurassic, Jurassic and Triassic, Triassic and Permian, as well as the Permian Upper Urho Formation and the underlying strata (Zhu et al, 2021;Chen et al, 2022;Huang et al, 2022).…”