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

2020 ◽  
pp. 1-49
Author(s):  
Nelson Sánchez ◽  
Jael pacheco ◽  
Mario Alberto Guzman-Vega ◽  
Andrés Mora ◽  
Brian Horton

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.

2018 ◽  
Vol 36 (5) ◽  
pp. 1229-1244
Author(s):  
Xiao-Rong Qu ◽  
Yan-Ming Zhu ◽  
Wu Li ◽  
Xin Tang ◽  
Han Zhang

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.


Lithosphere ◽  
2021 ◽  
Vol 2021 (Special 1) ◽  
Author(s):  
Xiaojun Li ◽  
Jingchun Tian ◽  
Miao Wang ◽  
Yong Chen

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.


Author(s):  
A., C. Prasetyo

Overpressure existence represents a geological hazard; therefore, an accurate pore pressure prediction is critical for well planning and drilling procedures, etc. Overpressure is a geological phenomenon usually generated by two mechanisms, loading (disequilibrium compaction) and unloading mechanisms (diagenesis and hydrocarbon generation) and they are all geological processes. This research was conducted based on analytical and descriptive methods integrated with well data including wireline log, laboratory test and well test data. This research was conducted based on quantitative estimate of pore pressures using the Eaton Method. The stages are determining shale intervals with GR logs, calculating vertical stress/overburden stress values, determining normal compaction trends, making cross plots of sonic logs against density logs, calculating geothermal gradients, analyzing hydrocarbon maturity, and calculating sedimentation rates with burial history. The research conducted an analysis method on the distribution of clay mineral composition to determine depositional environment and its relationship to overpressure. The wells include GAP-01, GAP-02, GAP-03, and GAP-04 which has an overpressure zone range at depth 8501-10988 ft. The pressure value within the 4 wells has a range between 4358-7451 Psi. Overpressure mechanism in the GAP field is caused by non-loading mechanism (clay mineral diagenesis and hydrocarbon maturation). Overpressure distribution is controlled by its stratigraphy. Therefore, it is possible overpressure is spread quite broadly, especially in the low morphology of the “GAP” Field. This relates to the delta depositional environment with thick shale. Based on clay minerals distribution, the northern part (GAP 02 & 03) has more clay mineral content compared to the south and this can be interpreted increasingly towards sea (low energy regime) and facies turned into pro-delta. Overpressure might be found shallower in the north than the south due to higher clay mineral content present to the north.


2021 ◽  
Vol 44 (3) ◽  
pp. 349-384 ◽  
Author(s):  
V. Aghayeva ◽  
R. F. Sachsenhofer ◽  
C.G.C. van Baak ◽  
A. Bechtel ◽  
T. M. Hoyle ◽  
...  

1998 ◽  
Vol 8 (1) ◽  
pp. 21-41 ◽  
Author(s):  
Beatrice Forbes Manz

Temür has been many things to many people. He was nomad and city-builder, Turk and promoter of Persian culture, restorer of the Mongol order and warrior for the spread of Islam. One thing he was to all: a conqueror of unequalled scope, able to subdue both the vast areas of nomad power to the north and the centres of agrarian Islamic culture to the south. The history of his successors was one of increasing political fragmentation and economic stress. Yet they too won fame, as patrons over a period of brilliant cultural achievement in Persian and Turkic. Temür's career raises a number of questions. Why did he find it necessary to pile conquest upon conquest, each more ambitious than the last? Having conceived dreams of dominion, where did he get the power and money to fulfill them? When he died, what legacy did Temür leave to his successors and to the world which they tried to control? Finally, what was this world of Turk and Persian, and where did Temür and the Timurids belong within it?


1985 ◽  
Vol 24 (95) ◽  
pp. 327-340
Author(s):  
Francis Thompson

The Irish land act of 1881, it is generally agreed, was a victory for the Land League and Parnell, and nationalist policy with regard to the act and the attitude of southern tenants towards it have been many times subjected to detailed examination by historians of this period. In these analyses of the events of 1880–81, however, little reference is normally made to the part played by the different parties and interests in the north of the country. It is often assumed, for example, that the Ulster tenants held aloof from the campaign for reform, lending no more than occasional vocal support to the agitational efforts of tenants in the south and west. Indeed, they were later excoriated by William O'Brien, Michael Davitt and others not only for giving no support to the land movement but also for sabotaging Parnell's policy of testing the 1881 act by precipitately rushing into the land courts to take advantage of the new legislation: ‘that hard-fisted body of men, having done nothing themselves to win the act, thought of nothing but turning it to their own immediate use, and repudiating any solidarity with the southern and western rebels to whom they really owed it’. If, however, northern tenants were harshly judged by nationalist politicians in the years after 1881, the part played by the northern political parties in the history of the land bill has been either ignored or misunderstood by historians since that time. The Ulster liberals, for example, are rarely mentioned, the implication being that they made no contribution to the act even though it implemented almost exactly the programme on which they had been campaigning for much of the previous decade. The northern conservatives, on the other hand, are commonly seen as leading opponents of the bill, more intransigent than their party colleagues in the south, ‘quick to denounce any weakening of the opposition’ to reform, and ‘determined to keep the tory party up to the mark in defending the landlord interest’


2021 ◽  
Author(s):  
Jennifer Spalding ◽  
Jeremy Powell ◽  
David Schneider ◽  
Karen Fallas

<p>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 ± 5.1 Ma, 59.5 ± 5.2 and 101.6 ± 6.7 Ma, respectively, and corresponding U-Pb ages of 497.4 ± 17.5 Ma (MSWD: 7.4), 353.5 ± 13.5 Ma (MSWD: 3.1) and 261.2 ± 8.5 Ma (MSWD: 5.9). All AFT data fail the χ<sup>2</sup> 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 r<sub>mro</sub> parameter uses grain specific chemistry to predict apatite’s kinetic behaviour and is used to identify kinetic populations within samples. Grain chemistry was measured via electron microprobe analysis to derive r<sub>mro</sub> values and each sample was separated into two kinetic populations that pass the χ<sup>2</sup> test: a less retentive population with ages ranging from 49.3 ± 9.3 Ma to 36.4 ± 4.7 Ma, and a more retentive population with ages ranging from 157.7 ± 19 Ma to 103.3 ± 11.8 Ma, with r<sub>mr0</sub> benchmarks ranging from 0.79 and 0.82. Thermal history models reveal Devonian strata reached maximum burial temperatures (~165°C-185°C) prior to late Paleozoic to Mesozoic unroofing, and reheated to lower temperatures (~75°C-110°C) in the Late Cretaceous to Paleogene. Both Cretaceous samples record maximum burial temperatures (75°C-95°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.</p>


2001 ◽  
Author(s):  
Mordechai Cogan

Beginning with the death of David and the rise of Solomon, 1 Kings charts the history of Israel through the divided monarchy, when Ahab reigned in the north and Jehoshaphat reigned in the south. This new translation, with introduction and commentary by biblical scholar Mordechai Cogan, is part of the Anchor Bible Commentary series, viewed by many as the definitive commentaries for use in both Christian and Jewish scholarship and worship. Cogan's translation brings new immediacy to well-known passages, such as Solomon's famously wise judgment when asked by two prostitutes to decide their dispute regarding motherhood of a child: "Cut the live son in two! And give half to one and half to the other." With a bibliography that runs to almost a thousand articles and books, Cogan's commentary demonstrates his mastery of the political history described by 1 Kings, as well as the themes of moral and religious failure that eventually led to Israel's defeat and exile.


2022 ◽  
pp. 1-42
Author(s):  
Xiaojun Zhu ◽  
Jingong Cai ◽  
Feng Liu ◽  
Qisheng Zhou ◽  
Yue Zhao ◽  
...  

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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