Sources of authigenic quartz in the Permian tight sandstones close to Gaoqing Fault, Dongying Sag, Bohai Bay Basin, China

Diagenetic Fluid and Its Impact on Sandstone Reservoirs in the Southern Boxing Sag, Dongying Depression, Bohai Bay Basin, China

“…Wang et al [21,22] reported that the silica sources for quartz overgrowths were mainly influenced by hydrothermal fluids in the Permian Upper Shihezi Formation sandstones at the Qingcheng Rise, which is approximately only 15 km away from the wells in the study area (Figure 1), because the Th ( °C) of aqueous inclusions was higher than its maximum burial temperature, δEu anomaly, and the enrichment of several trace elements in quartz overgrowths. However, quartz overgrowths of samples herein do not appear abnormally high Th value of aqueous inclusions and the presence of different of major elements (Figures 11 and 13).…”

“…Besides, previous research indicated that the micritic carbonate within mudstones in the Dongying Depression exhibited a high content of Sr 2+ [14], which gradually entered into pore water, resulting in a high SrO content in late-stage carbonate. The presence of barite was normally associated with hydrothermal fluid [21,22]. The barite mineral has markedly low solubility, whereas barium is common within the organic matter [48,49].…”

“…The use of major and minor elements together with C-O isotope of carbonate minerals was the most widespread methods to track the source of fluids and the organic-inorganic reactions in siliciclastic rock reservoirs (e.g., [14][15][16][17][18][19]). Fluid inclusions within authigenic minerals were conducted to ascertain the time of fluid combining with the burial history [20][21][22] and provided additional evidence to distinguish the origin of diagenetic fluids [23]. Over the past few years, electron probe microanalysis (EPMA), laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS), and sec-ondary ion mass spectrometry (SIMS) were gradually applied in diagenetic fluid research owing to the development of in situ testing technologies (e.g., [24][25][26]), which helped in revealing fluid characteristics and in understanding diagenetic transformation during the burial process.…”

“…Sandstones in the Shahejie Formation normally 2 Geofluids underwent complicated diagenesis. Previous studies have demonstrated that compaction is the primary factor for reducing the reservoir properties, followed by cementation, further increasing the heterogeneities of the pore structure as well as decreasing the reservoir porosity and permeability [21,22,30]. Carbonate minerals, authigenic quartz, and clay minerals are the most common diagenetic cements within sandstones in the Boxing Sag.…”

Coupling relationship between reservoir densification and hydrocarbon emplacement in the Jurassic Badaowan Formation sandstone reservoirs of the southern Junggar Basin, China

“…It has been a key topic in the exploration and development of tight sandstone reservoirs to elucidate the spatiotemporal interrelationship between tight sandstone reservoir densification and hydrocarbon emplacement (Huyan et al, 2019; Yu et al, 2017). Three types of interrelationships were identified in the previous studies (Huyan et al, 2019; Y. Wang et al, 2020; Yu et al, 2017), including ‘hydrocarbon emplacement after reservoir densification’, ‘hydrocarbon emplacement before reservoir densification’, and ‘hydrocarbon emplacement during reservoir densification’. For the first type of interrelationship, several key factors are controlling the oil content in the tight sandstone reservoir, including the complexity of the pore‐throat structure, the driving force of hydrocarbon migration, the effect of hydrocarbon emplacement on diagenesis, and the change of reservoir wettability.…”