NEW GEOCHEMICAL INSIGHTS INTO CENOZOIC SOURCE ROCKS IN AZERBAIJAN: IMPLICATIONS FOR PETROLEUM SYSTEMS IN THE SOUTH CASPIAN REGION

The South Sumatra Basin has been a focus for hydrocarbon exploration since the earliest oil discoveries in the late 1890s. Despite production of over 2500MMbbls of oil and 9.5TCF of gas our regional understanding of the basin’s petroleum systems is still evolving. Most discoveries occur along a series of Late Neogene NNW-SSE elongated anticlines. The most prolific reservoirs are fluvial – shallow marine sandstones of the Upper Oligocene – Lower Miocene Talang Akar Formation but hydrocarbons have also been discovered in numerous sandstone and carbonate reservoirs ranging in age from Middle – Late Miocene to Eocene. Pre-Tertiary fractured Basement reservoirs are also important gas producers. A geochemical database for produced, tested and seep oils and gases has been compiled from the analytical reports, produced by different service companies over a 40-year period, to understand the spatial distribution of hydrocarbon types and relate this to source type, source maturity and migration patterns. Integration with published palaeoenvironmental reconstructions for the time intervals associated with source rock deposition has enabled a better understanding of migration directions and migration limits. The database of over 100 oils and 40 gases has revealed a wider variation in geochemical character than previously thought, indicating the presence of numerous fluvio-deltaic and lacustrine types suggesting subtle variations in the character of the effective source rocks within the basin, related to both organic matter type and depositional environment. Seven major oil families, often with several sub-groups, have been identified, while the presence of both biogenic and thermogenic gases of varying maturities are also noted. Spatial analysis of these hydrocarbons, integrated with source rock indications, palaeoenvironmental reconstructions and structural maps have allowed definition of kitchen areas and drainage areas for these hydrocarbon accumulations and a better understanding of the charge risk and likely hydrocarbon type in undrilled areas.

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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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The petroleum systems and future potential of the South Sumatra basin

10.29118/ipa.2226.05.g.039 ◽

2018 ◽

Cited By ~ 2

Author(s):

D. Ginger

Keyword(s):

The South ◽

Petroleum Systems ◽

Future Potential

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Research for the Upstream Petroleum Sector: The Crown Research Institute Concept

Energy Exploration & Exploitation ◽

10.1177/0144598795013002-313 ◽

1995 ◽

Vol 13 (2-3) ◽

pp. 245-252

Author(s):

J M Beggs

Keyword(s):

New Zealand ◽

Oil And Gas ◽

Sedimentary Basins ◽

Source Rocks ◽

Publicly Funded ◽

Petroleum Systems ◽

Oil And Gas Resources ◽

Petroleum Sector ◽

Geological Sciences ◽

Research Institute

New Zealand's scientific institutions have been restructured so as to be more responsive to the needs of the economy. Exploration for and development of oil and gas resources depend heavily on the geological sciences. In New Zealand, these activities are favoured by a comprehensive, open-file database of the results of previous work, and by a historically publicly funded, in-depth knowledge base of the extensive sedimentary basins. This expertise is now only partially funded by government research contracts, and increasingly undertakes contract work in a range of scientific services to the upstream petroleum sector, both in New Zealand and overseas. By aligning government-funded research programmes with the industry's knowledge needs, there is maximum advantage in improving the understanding of the occurrence of oil and gas resources. A Crown Research Institute can serve as an interface between advances in fundamental geological sciences, and the practical needs of the industry. Current publicly funded programmes of the Institute of Geological and Nuclear Sciences include a series of regional basin studies, nearing completion; and multi-disciplinary team studies related to the various elements of the petroleum systems of New Zealand: source rocks and their maturation, migration and entrapment as a function of basin structure and tectonics, and the distribution and configuration of reservoir systems.

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The source rocks in the southwestern part of the South Sakhalin Basin

Moscow University Geology Bulletin ◽

10.3103/s0145875217010045 ◽

2017 ◽

Vol 72 (1) ◽

pp. 63-74

Author(s):

T. A. Kiryukhina ◽

S. I. Bordunov ◽

A. A. Solov’eva

Keyword(s):

Source Rocks ◽

The South ◽

Southwestern Part ◽

South Sakhalin

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Hydrocarbon fluid inclusions in the Argo salt, offshore Canadian Atlantic margin

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2012-0040 ◽

2013 ◽

Vol 50 (6) ◽

pp. 607-635 ◽

Cited By ~ 4

Author(s):

Yawooz A. Kettanah

Keyword(s):

Fluid Inclusions ◽

Fluorescent Microscopy ◽

Freezing Temperature ◽

Homogenization Temperature ◽

Source Rocks ◽

Late Triassic ◽

Peritectic Temperature ◽

Petroleum Systems ◽

Initial Melting ◽

Atlantic Margin

Fluid inclusions hosted in rock salt from the Triassic Argo Formation in the Canadian Atlantic continental margin were studied to investigate the nature and origin of petroleum fluids in them. Inclusions were studied in two wells: Glooscap-C63 and Weymouth-A45. The pillow-shaped salt body intersected by the Glooscap-C63 well is autochthonous, and the salt is transparent and colorless compared with that in the allochthonous, canopy–diaper-shaped body cut by the Weymouth-A45 well which is translucent and buff-colored. Aqueous (AFI), petroleum (PFI), and heterogeneously trapped, mixed petroleum – aqueous (MFI) fluid inclusions were identified using transmitted and fluorescent microscopy, and representative samples were analyzed microthermometrically. Petroleum-bearing fluid inclusions (PFI and MFI) are more common and contain more concentrated petroleum phases in the allochthonous salts of Weymouth-A45 well. Based on microthermometric studies, the AFI and MFI in Glooscap-C63 salt mostly belong to NaCl–H2O and NaCl–H2O–petroleum systems, respectively; in contrast, those of Weymouth-A45 belong to NaCl–MgCl2–H2O and (or) NaCl–CaCl2–H2O and NaCl–MgCl2–H2O–petroleum and (or) NaCl–CaCl2–H2O–petroleum systems, respectively. Each of the AFI, PFI, and MFI types consists of different phases. The medians of Tf (freezing temperature), Tim (initial melting temperature), Te (Eutectic temperature), Tm (final melting (peritectic) temperature), and Th (homogenization temperature) in the AFI and MFI in the salts of Glooscap-C63 well are (−82, −75 °C), (−39, −38 °C), (−25, −24 °C), (−1.8, −3 °C), and (291, 287 °C), respectively. The corresponding medians for the Weymouth-A45 well are (−71, −78 °C), (−52, −52 °C), (−37, −38 °C), (−2.7, −3 °C), and (122, 20 °C), respectively. The median Th of PFI in Glooscap-C63 and Weymouth-A45 salts are 79 and 23 °C, respectively. The most probable source rocks for the petroleum are the shales of the Late Triassic – Early Jurassic Eurydice Formation which is widely distributed at depth underlying the Argo salt.

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Petroleum systems and results of exploration on the Atlantic margins of the UK, Faroes & Ireland: what have we learnt?

Geological Society London Petroleum Geology Conference series ◽

10.1144/pgc8.14 ◽

2016 ◽

Vol 8 (1) ◽

pp. 187-197 ◽

Cited By ~ 7

Author(s):

Iain C. Scotchman ◽

Anthony G. Doré ◽

Anthony M. Spencer

Keyword(s):

Upper Jurassic ◽

Petroleum System ◽

Source Rocks ◽

Gas Field ◽

Petroleum Systems ◽

Unknown Source ◽

Porcupine Basin ◽

Break Up ◽

Northern North Sea ◽

The Uk

AbstractThe exploratory drilling of 200 wildcat wells along the NE Atlantic margin has yielded 30 finds with total discovered resources of c. 4.1×109 barrels of oil equivalent (BOE). Exploration has been highly concentrated in specific regions. Only 32 of 144 quadrants have been drilled, with only one prolific province discovered – the Faroe–Shetland Basin, where 23 finds have resources totalling c. 3.7×109 BOE. Along the margin, the pattern of discoveries can best be assessed in terms of petroleum systems. The Faroe–Shetland finds belong to an Upper Jurassic petroleum system. On the east flank of the Rockall Basin, the Benbecula gas and the Dooish condensate/gas discoveries have proven the existence of a petroleum system of unknown source – probably Upper Jurassic. The Corrib gas field in the Slyne Basin is evidence of a Carboniferous petroleum system. The three finds in the northern Porcupine Basin are from Upper Jurassic source rocks; in the south, the Dunquin well (44/23-1) suggests the presence of a petroleum system there, but of unknown source. This pattern of petroleum systems can be explained by considering the distribution of Jurassic source rocks related to the break-up of Pangaea and marine inundations of the resulting basins. The prolific synrift marine Upper Jurassic source rock (of the Northern North Sea) was not developed throughout the pre-Atlantic Ocean break-up basin system west of Britain and Ireland. Instead, lacustrine–fluvio-deltaic–marginal marine shales of predominantly Late Jurassic age are the main source rocks and have generated oils throughout the region. The structural position, in particular relating to the subsequent Early Cretaceous hyperextension adjacent to the continental margin, is critical in determining where this Upper Jurassic petroleum system will be most effective.

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Resolving thermal histories via multi-kinetic apatite fission track data: A case study from Phanerozoic strata within the Peel Plateau NWT, Canada

10.5194/egusphere-egu21-3135 ◽

2021 ◽

Author(s):

Jennifer Spalding ◽

Jeremy Powell ◽

David Schneider ◽

Karen Fallas

Keyword(s):

Low Temperature ◽

Thermal History ◽

Fission Track ◽

Sedimentary Basins ◽

Source Rocks ◽

Apatite Fission Track ◽

Petroleum Systems ◽

History Of ◽

Thermal Histories ◽

Peel Plateau

Resolving the thermal history of sedimentary basins through geological time is essential when evaluating the maturity of source rocks within petroleum systems. Traditional methods used to estimate maximum burial temperatures in prospective sedimentary basin such as and vitrinite reflectance (%Ro) are unable to constrain the timing and duration of thermal events. In comparison, low-temperature thermochronology methods, such as apatite fission track thermochronology (AFT), can resolve detailed thermal histories within a temperature range corresponding to oil and gas generation. In the Peel Plateau of the Northwest Territories, Canada, Phanerozoic sedimentary strata exhibit oil-stained outcrops, gas seeps, and bitumen occurrences. Presently, the timing of hydrocarbon maturation events are poorly constrained, as a regional unconformity at the base of Cretaceous foreland basin strata indicates that underlying Devonian source rocks may have undergone a burial and unroofing event prior to the Cretaceous. Published organic thermal maturity values from wells within the study area range from 1.59 and 2.46 %Ro for Devonian strata and 0.54 and 1.83 %Ro within Lower Cretaceous strata. Herein, we have resolved the thermal history of the Peel Plateau through multi-kinetic AFT thermochronology. Three samples from Upper Devonian, Lower Cretaceous and Upper Cretaceous strata have pooled AFT ages of 61.0 &#177; 5.1 Ma, 59.5 &#177; 5.2 and 101.6 &#177; 6.7 Ma, respectively, and corresponding U-Pb ages of 497.4 &#177; 17.5 Ma (MSWD: 7.4), 353.5 &#177; 13.5 Ma (MSWD: 3.1) and 261.2 &#177; 8.5 Ma (MSWD: 5.9). All AFT data fail the &#967;2 test, suggesting AFT ages do not comprise a single statistically significant population, whereas U-Pb ages reflect the pre-depositional history of the samples and are likely from various provenances. Apatite chemistry is known to control the temperature and rates at which fission tracks undergo thermal annealing. The rmro parameter uses grain specific chemistry to predict apatite&#8217;s kinetic behaviour and is used to identify kinetic populations within samples. Grain chemistry was measured via electron microprobe analysis to derive rmro values and each sample was separated into two kinetic populations that pass the &#967;2 test: a less retentive population with ages ranging from 49.3 &#177; 9.3 Ma to 36.4 &#177; 4.7 Ma, and a more retentive population with ages ranging from 157.7 &#177; 19 Ma to 103.3 &#177; 11.8 Ma, with rmr0 benchmarks ranging from 0.79 and 0.82. Thermal history models reveal Devonian strata reached maximum burial temperatures (~165&#176;C-185&#176;C) prior to late Paleozoic to Mesozoic unroofing, and reheated to lower temperatures (~75&#176;C-110&#176;C) in the Late Cretaceous to Paleogene. Both Cretaceous samples record maximum burial temperatures (75&#176;C-95&#176;C) also during the Late Cretaceous to Paleogene. These new data indicate that Devonian source rocks matured prior to deposition of Cretaceous strata and that subsequent burial and heating during the Cretaceous to Paleogene was limited to the low-temperature threshold of the oil window. Integrating multi-kinetic AFT data with traditional methods in petroleum geosciences can help unravel complex thermal histories of sedimentary basins. Applying these methods elsewhere can improve the characterisation of petroleum systems.

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Comparisons of pyrolysis parameters between source rocks and their clay-sized fractions: Implication for source material of hydrocarbon generation

Interpretation ◽

10.1190/int-2021-0126.1 ◽

2022 ◽

pp. 1-42

Author(s):

Xiaojun Zhu ◽

Jingong Cai ◽

Feng Liu ◽

Qisheng Zhou ◽

Yue Zhao ◽

...

Keyword(s):

Organic Carbon ◽

Source Material ◽

Source Rocks ◽

Natural Environments ◽

Hydrocarbon Generation ◽

Petroleum Systems ◽

Organic Mineral ◽

Organic Clay ◽

Organo Clay ◽

Rock Eval

In natural environments, organic-clay interactions are strong and cause organo-clay composites (a combination between organic matter [OM] and clay minerals) to be one of the predominant forms for OM occurrence, and their interactions greatly influence the hydrocarbon (HC) generation of OM within source rocks. However, despite occurring in nature, dominating the OM occurrence, and having unique HC generation ways, organo-clay composites have rarely been investigated as stand-alone petroleum precursors. To improve this understanding, we have compared the Rock-Eval pyrolysis parameters derived from more than 100 source rocks and their corresponding <2 μm clay-sized fractions (representing organo-clay composites). The results show that all of the Rock-Eval pyrolysis parameters in bulk rocks are closely positively correlated with those in their clay-sized fractions, but in clay-sized fractions the quality of OM for HC generation is poorer, in that the pyrolysable organic carbon levels and hydrogen index values are lower, whereas the residual organic carbon levels are higher than those in bulk rocks. Being integrated with the effects of organic-clay interactions on OM occurrence and HC generation, our results suggest that organo-clay composites are stand-alone petroleum precursors for HC generation occurring in source rocks, even if the source rocks exist in great varieties in their attributes. Our source material for HC generation comprehensively integrates the original OM occurrence and HC generation behavior in natural environments, which differs from kerogen and is much closer to the actual source material of HC generation in source rocks, and it calls for further focus on organic-mineral interactions in studies of petroleum systems.

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