Article
Geosciences, Multidisciplinary
Umid Kakemem, Mohammadfarid Ghasemi, Mohammad Hossein Adabi, Antun Husinec, Ayoub Mahmoudi, Kresten Anderskouv
Summary: A sedimentological and sequence stratigraphic analysis was conducted on cores from gas fields in the Persian Gulf to evaluate a method for automatic reservoir zonation. The study found that the reservoir quality of the Upper Dalan Formation is influenced by various factors, including dolomitization, dissolution, pore-filling anhydrite cementation, compaction, and over-dolomitization.
MARINE AND PETROLEUM GEOLOGY
(2023)
Article
Multidisciplinary Sciences
Morrison R. Nolan, Sally E. Walker, Tara Selly, James Schiffbauer
Summary: This study presents new morphological, chemical, and structural data to evaluate the affinities of Brooksella and determine whether it is a hexactinellid sponge or a trace fossil. The findings suggest that Brooksella is not a hexactinellid sponge or a trace fossil, but rather an unusual form of silica concretion. The study highlights the importance of thorough and accurate descriptions in Cambrian paleontology, considering both biotic and abiotic hypotheses for fossils.
Article
Geosciences, Multidisciplinary
C. A. Sidor, J. A. Mcintosh, B. M. Gee, W. R. Hammer, P. J. Makovicky, N. D. Smith, R. M. H. Smith, N. J. Tabor, M. R. Whitney, C. H. Woolley
Summary: The Permian-Triassic rocks in the Transantarctic Basin offer a valuable record of high latitude paleoenvironments and terrestrial vertebrate faunas. This study summarizes the taxonomic and paleoecological implications of collected vertebrate fossils and presents new geological observations. The results reveal the similarities and differences between the Fremouw Formation and the Karoo Basin, as well as provide insights into the depositional environments and diagenetic alterations of these formations.
EARTH-SCIENCE REVIEWS
(2023)
Article
Geosciences, Multidisciplinary
Dawei Cheng, Chuanmin Zhou, Zhijie Zhang, Xuanjun Yuan, Yinhe Liu, Xingyu Chen
Summary: The study focused on the Lucaogou Formation in the southeastern Junggar Basin. Analysis of sedimentology, major and trace elements, mineral components and total organic carbon contents revealed different depositional environments and organic matter accumulation mechanisms in the upper and lower units. The lower unit was influenced by primary productivity, while the upper unit was controlled by redox conditions.
JOURNAL OF EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Lu Wang, Xiaodong Guan, Jianyong Wang, Zuoyu Sun, Huiyuan Xu
Summary: This study found that rock layers in deep-water sedimentary environments in the Sichuan Basin are generally rich in organic matter and have high total organic carbon (TOC) content. It also found that high-quality shale oil and gas mainly form in anoxic restricted environments, and that hydrothermal activity of submarine volcanoes provides nutrients and compounds for the formation of organic matter.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Multidisciplinary Sciences
William J. Foster, Amanda Godbold, Arnaud Brayard, Anja B. Frank, Stephen E. Grasby, Richard J. Twitchett, Tatsuo Oji
Summary: This study presents a paleoecological analysis of the Hiraiso Formation in northeast Japan, revealing the temporal and spatial variations of diversity, ecological structure, and taxonomic composition in the Early Triassic marine ecosystems. The study suggests that the benthic fauna in the Hiraiso Formation represents an advanced stage of ecological recovery, but not full recovery. The distribution of the benthic fauna supports the habitable zone hypothesis and is consistent with oxygen gradients in modern environments.
Article
Chemistry, Multidisciplinary
Fei Hu, Zhao-Jun Liu, Jianpeng Wang
Summary: This study investigates the provenance characteristics of mudstones, siltstones, and fine sandstones in eastern Inner Mongolia, China, through petrographic, mineralogical, and geochemical analyses. The results indicate that these sediments mainly originate from rhyolitic, basaltic andesitic, and andesitic tuff deposits in the early Permian. The tectonic setting of the provenance area is identified as a continental island arc related to the active continental margin.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Article
Geosciences, Multidisciplinary
Wei Wu, Weiqing Liu, Chuanlong Mou, Hua Liu, Yu Qiao, Jienan Pan, Shuyuan Ning, Xiaoxiao Zhang, Jianxin Yao, Jingdong Liu
Summary: Based on geochemical data, the study analyzed the sources, climate, environment and mechanism of organic matter enrichment of the Upper Permian Dalong Formation in western Hubei Province. The formation can be divided into organic-rich and organic-lean shales, deposited under anoxic-sulfurized and oxic-suboxic conditions respectively. The decrease in primary productivity due to transition in climate was identified as the main factor controlling organic matter enrichment and bioquartz formation.
MARINE AND PETROLEUM GEOLOGY
(2021)
Article
Geography, Physical
Xueqian Feng, Zhong-Qiang Chen, Laishi Zhao, Zhongwu Lan
Summary: The study describes Guadalupian (middle Permian) ichnoassemblages, identifying multiple facies and trace types, indicating biodiversity and behavioral diversity. Changes in traces from the Permian to Middle Triassic suggest potential ichnological evolution.
GLOBAL AND PLANETARY CHANGE
(2021)
Article
Multidisciplinary Sciences
Zhuosen Yao, James E. Mungall
Summary: The Main Magnetite Layer of the Bushveld Complex in South Africa is rich in iron, titanium, and vanadium, but its formation remains enigmatic. Previous models required frequent adjustments, while an alternative model fits observations without any modifications. The choice of models is crucial for understanding the formation of layered intrusions.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Junxin Shang, Mingyou Feng, Xingzhi Wang, Benjian Zhang, Liang Xu, Xiaohong Liu
Summary: The Middle Permian Qixia Formation in the southwestern region of Sichuan has undergone multiple phases of fluidization, leading to an unclear understanding of the reservoir reconstruction effect. This study conducted a systematic analysis of the Qi2 member in Wulong Town using field outcrop petrology and geochemistry. The results revealed the vertical stacking of multiple sets of crystalline dolomite-bioclastic limestone cycles, accompanied by fractures and karst channels. The impact of karstification on the reservoir was minor, with most products of karstification being distributed as fillings in channels. The hydrothermal solution mainly filled fractures, pores, and early karst channels. The middle and upper parts of the middle Permian Qixia Formation were mainly damaged by karstification and the hydrothermal solution. The episodic fluid impact on the restoration of the carbonate reservoir was mainly restricted by channels for fluid migration and thickness differences among the reservoir. However, certain thick-layered and massive crystalline dolomite show promise for exploration.
SCIENTIFIC REPORTS
(2023)
Article
Geography, Physical
Yamin Yu, Pingping Li, Ruixin Guo, Yizhen Zhao, Shan Li, Huayao Zou
Summary: This study reveals the vertical variation in organic matter enrichment of the Upper Permian Dalong Formation in the northern Sichuan Basin, which was related to the expansion of the Paleo-Tethys Ocean induced transgression and upwelling in the northern continental margin of the Upper Yangtze. The differences in types and strength of the upwelling result in the variation of paleoproductivity and redox conditions, and thus the organic matter abundance in the sedimentary rocks.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Ya Zhang, Shuangling Chen, Long Wen, Benjian Zhang, Hua Wang, Di Xiao, Chen Xie, Xiaoli Zhang, Li Quan, Ran Liu, Yanping Qiao, Guangwei Wang
Summary: Exploration of natural gases in the Middle Permian Qixia Formation in the central and western Sichuan Basin has achieved a significant breakthrough. The study reveals that high-quality dolomite reservoirs, mudstone source rocks, and structural traps provide the basis for large-scale natural gas enrichment. The Qixia gases originated mainly from Cambrian and Permian rocks, with structural high zones being favorable for hydrocarbon accumulation.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Qian Cao, Minghui Qi, Xiawei Li, Daifu Wang, Yuwei Deng, Chongyu Wu
Summary: The study analyzed the reservoir space development characteristics and geochemical parameters of the Permian Longtan Formation in the southeast of the Sichuan Basin at Well X1. The results showed that the deposition environment was warm and humid, with a small deposition rate. The clay mineral content and organic matter content played a major role in controlling the reservoir space development.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geology
Xin Jiao, Yi-Qun Liu, Wan Yang, Hong Li, Zi-Yuan Meng, Min-Ru Zhao, Zhe-Xuan Li
Summary: This study suggests a non-evaporitic origin of dolomite in a volcanic-hydrothermal lake, where the dolomite primarily originated from fluids that migrated upward from the mantle. The formation of dolomite was influenced by high temperatures and abundant Mg2+ supply from a deep source.
Article
Geosciences, Multidisciplinary
Dirk Knaust, Roger D. K. Thomas, H. Allen Curran
EARTH-SCIENCE REVIEWS
(2018)
Article
Geosciences, Multidisciplinary
Dirk Knaust
EARTH-SCIENCE REVIEWS
(2018)
Article
Paleontology
Dirk Knaust, Nicholas J. Minter
Article
Paleontology
Dirk Knaust
Article
Paleontology
Dirk Knaust
Review
Geosciences, Multidisciplinary
Dirk Knaust
EARTH-SCIENCE REVIEWS
(2019)
Article
Paleontology
Dirk Knaust
ICHNOS-AN INTERNATIONAL JOURNAL FOR PLANT AND ANIMAL TRACES
(2019)
Article
Geology
Max Wisshak, Dirk Knaust, Markus Bertling
Article
Geosciences, Multidisciplinary
Dirk Knaust, Andre Desrochers
Article
Paleontology
Dirk Knaust
Article
Paleontology
Dirk Knaust, Andre Desrochers
Article
Geosciences, Multidisciplinary
Dirk Knaust, Javier Dorador, Francisco J. Rodriguez-Tovar
MARINE AND PETROLEUM GEOLOGY
(2020)
Article
Paleontology
Dirk Knaust
Article
Paleontology
Dirk Knaust, Rene Hoffmann
Summary: The trace fossil Lumbricaria Munster is a common constituent of the Upper Jurassic lithographic limestones in southern Germany, with cephalopods, particularly nautiloids or ammonites, being the most likely producers of Lumbricaria according to a morphological analysis and comparison with modern analogues.
PAPERS IN PALAEONTOLOGY
(2021)
Article
Paleontology
Dirk Knaust
PAPERS IN PALAEONTOLOGY
(2020)