Analyzing geochemical characteristics and hydrocarbon generation history of the Middle and Upper Jurassic source rocks in the North Yellow Sea Basin

The Huanghua Depression is located in the north-centre of Bohai Bay Basin, which is a rift basin developed in the Mesozoic over the basement of the Huabei Platform, China. Permo-Carboniferous source rocks were formed in the Huanghua Depression, which has experienced multiple complicated tectonic alterations with inhomogeneous uplift, deformation, buried depth and magma effect. As a result, the hydrocarbon generation evolution of Permo-Carboniferous source rocks was characterized by discontinuity and grading. On the basis of a detailed study on tectonic-burial history, the paper worked on the burial history, heating history and hydrocarbon generation history of Permo-Carboniferous source rocks in the Huanghua Depression combined with apatite fission track testing and fluid inclusion analyses using the EASY% Ro numerical simulation. The results revealed that their maturity evolved in stages with multiple hydrocarbon generations. In this paper, we clarified the tectonic episode, the strength of hydrocarbon generation and the time–spatial distribution of hydrocarbon regeneration. Finally, an important conclusion was made that the hydrocarbon regeneration of Permo-Carboniferous source rocks occurred in the Late Cenozoic and the subordinate depressions were brought forward as advantage zones for the depth exploration of Permo-Carboniferous oil and gas in the middle-northern part of the Huanghua Depression, Bohai Bay Basin, China.

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MATURATION PATTERNS IN THE PERTH BASIN

The APPEA Journal ◽

10.1071/aj78011 ◽

1979 ◽

Vol 19 (1) ◽

pp. 94 ◽

Cited By ~ 1

Author(s):

A. J. Kantsler ◽

A. C. Cook

Keyword(s):

Vitrinite Reflectance ◽

Upper Jurassic ◽

Source Rocks ◽

Hydrocarbon Generation ◽

Geothermal Gradients ◽

The North ◽

Reservoir Conditions ◽

Igneous Activity ◽

Hydrocarbon Deposits ◽

Very High

Vitrinite reflectance data from wells drilled in the Perth Basin show that major variations exist in the pattern of rank distribution within the basin. Generally, rank gradients are low and near linear, but some wells show curvature of the rank profile in the Early Jurassic and Triassic parts of their sections. Curvature of the rank profile is generally associated with a shallow depth to basement, but the presence of very high ranks in parts of the Permian section on the Beagle Ridge suggests that a Permian to Jurassic thermal event associated with local igneous activity or the initiation of rifting, or both, may also be a controlling factor. Low, linear rank gradients from parts of the basin such as the Bunbury Trough and the thick Upper Jurassic sections of some of the deeper sub-basins are taken to indicate that low geothermal gradients have operated since the Permian,in the former instance and certainly since the Jurassic in the latter. Such conditions imply slow generation of hydrocarbons.Higher geothermal gradients and rank gradients in parts of the basin as in the north Dandaragan Trough and Vlaming Sub-basin imply enhanced hydrocarbon generation, particularly as calculated palaeotemperatures indicate that the advent of higher geothermal gradients is likely to have been relatively recent. Potential source rocks occur throughout the basin and provided that suitable structural and reservoir conditions can be delineated, the prospects of discovering more commercial hydrocarbon deposits are high.

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Characteristics and Geological Significance of the Hydrocarbon Source Rocks of the Qum Formation in Outcrop of the Northern Garmsar Area, Iran

Lithosphere ◽

10.2113/2021/3350725 ◽

2021 ◽

Vol 2021 (Special 1) ◽

Author(s):

Xiaojun Li ◽

Jingchun Tian ◽

Miao Wang ◽

Yong Chen

Keyword(s):

Organic Matter ◽

Vitrinite Reflectance ◽

Sedimentary Environment ◽

Source Rocks ◽

Type I ◽

Hydrocarbon Generation ◽

Soluble Organic Matter ◽

The North ◽

History Of ◽

Formation Conditions

Abstract The carbonate rocks were collected from the Qum Formation in outcrop of the northern Garmsar Area, Iran. In order to evaluating the hydrocarbon generation prospects of these source rocks, we analyzed their geochemical characteristics, including the abundance, type, and maturity of organic matter, and investigated their formation conditions by analyzing the characteristics of soluble organic matter and sedimentary environment. The results show that the organic matter abundance of the source rocks in the Qum Formation in the Garmsar Area is low in the north and west. The organic matter type is mainly II1-II2, locally showing type I and III, and in general, it is conducive to hydrocarbon generation. The maturity of organic matter is low, showing the Tmax between 416°C and 439°C, vitrinite reflectance (Ro) from 0.49% to 0.83%, which indicate it is at the stage of low to moderate maturity. The soluble organic matter characteristics indicated that the organic matter evolution of the source rocks in the Qum Formation is low. Through comparison between the study area and other areas, and different places within the working area, the abundance, type, and maturity of organic matter of the source rocks in the Qum Formation are different, caused by the basin facie zones, sedimentary environment, and history of sedimentation of the source rocks. Overall, the source rock in the Qum Formation in Garmsar Area has good prospects of hydrocarbon generation. This study has important significance for further exploration in the Garmsar Area.

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Timing of hydrocarbon entrapment in the Eastern Foothills of the Eastern Cordillera of Colombia

Interpretation ◽

10.1190/int-2020-0058.1 ◽

2020 ◽

pp. 1-49

Author(s):

Nelson Sánchez ◽

Jael pacheco ◽

Mario Alberto Guzman-Vega ◽

Andrés Mora ◽

Brian Horton

Keyword(s):

Source Rocks ◽

Hydrocarbon Generation ◽

The South ◽

Shallow Marine ◽

Origin And Evolution ◽

Eastern Cordillera ◽

Petroleum Systems ◽

The North ◽

Early Oligocene ◽

History Of

The Eastern Foothills in the Eastern Cordillera of Colombia have been an important oil producing region since the discovery of the Cupiagua and Cusiana fields. Several organic rich Cretaceous-Paleogene units have been considered to be the principal source rocks. The Aptian Fomeque Formation and the Cenomanian-Coniacian Chipaque Formation and the Paleocene Los Cuervos Formation. We modeled the petroleum systems of these three source units to characterize the hydrocarbon generation and accumulation processes within the basin. We found that the maturation history of the system was largely influenced by changes in crustal deformation produced during the tectonic evolution of the Colombian Andes. The Aptian Fomeque Formation. reached the oil window during the Paleocene in the south and the Eocene in the north. The Cenomanian-Coniacian Chipaque Formation reached the oil window in the south by the Early Oligocene and in the north by the Late Oligocene. In contrast, the Paleocene Los Cuervos Formation entered the oil generation window by the end of the Oligocene in both the North and South areas. Our model suggests that the charge history of the main reservoirs has a diverse history also. The shallow marine Albian sandstones were charged during Oligocene to Miocene. In contrast, the proven reservoirs in the area (including the Upper Cretaceous shallow marine reservoirs, the Paleocene fluvial reservoirs and the Eocene fluvial-estuarine reservoirs) were filled by the end of the Miocene, with a second episode of recent (and perhaps active) filling of the Eocene reservoirs from the Paleocene source rocks.The results suggest that petroleum systems modeling is useful not only to predict and characterize generation and migration processes, but also provides insights into the origin and evolution of present-day subsurface structures and the distribution of oil reservoirs in structurally complex areas such as the Colombian foothills.

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