Developmental modes of the Neoproterozoic-Lower Paleozoic marine hydrocarbon source rocks in China

This article provides stratigraphic and geochronological data from a central part of Gondwana’s northern margin — the Moroccan Meseta Domain. This region, located to the north of the Anti-Atlas area with extensive outcrops of Precambrian and lower Paleozoic rocks, has hitherto not received much attention with regard to its Precambrian geology. Detrital and volcanic zircon ages have been used to constrain sedimentary depositional ages and crustal affinities of sedimentary source rocks in stratigraphic key sections. Based on this, a four-step paleotectonic evolution of the Meseta Domain from the Ediacaran until the Early Ordovician is proposed. This evolution documents the transition from a terrestrial volcanic setting during the Ediacaran to a short-lived carbonate platform setting during the early Cambrian. The latter then evolved into a rifted margin with deposition of thick siliciclastic successions in graben structures during the middle to late Cambrian. The detritus in these basins was of local origin, and a contribution from a broader source area (encompassing parts of the West African Craton) can only be demonstrated for postrifting, i.e., laterally extensive sandstone bodies that seal the former graben. In a broader paleotectonic context, it is suggested that this Cambrian rifting is linked to the opening of the Rheic Ocean, and that several peri-Gondwanan terranes (Meguma and Cadomia–Iberia) may have been close to the Meseta Domain before drifting, albeit some of them seem to have been constituted by a distinctly different basement.

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Hydrocarbon Source Rocks In Deep Sea Sediments

10.4043/3408-ms ◽

1979 ◽

Cited By ~ 3

Author(s):

D.H. Welte ◽

C.H. Cornford ◽

J.H. Rullkotter

Keyword(s):

Deep Sea ◽

Source Rocks ◽

Hydrocarbon Source Rocks ◽

Deep Sea Sediments

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RbSr dating of fluid migration in hydrocarbon source rocks

Chemical Geology Isotope Geoscience section ◽

10.1016/0168-9622(87)90005-4 ◽

1987 ◽

Vol 65 (3-4) ◽

pp. 223-233 ◽

Cited By ~ 1

Author(s):

P.C. Smalley ◽

A. Forsberg ◽

A. Råheim

Keyword(s):

Source Rocks ◽

Fluid Migration ◽

Hydrocarbon Source Rocks

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Petrography and Organic Geochemistry Characterizations of Lower Paleozoic Organic-Rich Shale in the Northwestern Upper Yangtze Plate: Niutitang Formation and Longmaxi Formation, Dabashan Foreland Belt

Minerals ◽

10.3390/min8100439 ◽

2018 ◽

Vol 8 (10) ◽

pp. 439 ◽

Cited By ~ 1

Author(s):

Delu Li ◽

Rongxi Li ◽

Di Zhao ◽

Feng Xu

Keyword(s):

Gas Chromatography ◽

Organic Matter ◽

Organic Geochemistry ◽

Source Rocks ◽

Gas Chromatography Mass Spectrometry ◽

Mature Stage ◽

Type I ◽

Lower Paleozoic ◽

Longmaxi Formation ◽

Niutitang Formation

Measurements of total organic carbon, Rock-Eval pyrolysis, X-ray diffraction, scanning electron microscope, maceral examination, gas chromatography, and gas chromatography-mass spectrometry were conducted on the organic-rich shale of Lower Paleozoic Niutitang Formation and Longmaxi Formation in Dabashan foreland belt to discuss the organic matter characteristic, organic matter origin, redox condition, and salinity. The results indicate that the Niutiang Formation and Longmaxi Formation organic-rich shale are good and very good source rocks with Type I kerogen. Both of the shales have reached mature stage for generating gas. Biomarker analyses indicate that the organic matter origin of Niutitang Formation and Longmaxi Formation organic-rich shale are all derived from the lower bacteria and algae, and the organic matter are all suffered different biodegradation degrees. During Niutitang Formation and Longmaxi Formation period, the redox conditions are both anoxic with no stratification and the sedimentary water is normal marine water.

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