Geochemical and petrographic characterisation of organic matter from the Upper Cretaceous Fika shale succession in the Chad (Bornu) Basin, northeastern Nigeria: Origin and hydrocarbon generation potential

2015 ◽  
Vol 61 ◽  
pp. 95-110 ◽  
Author(s):  
Adebanji Kayode Adegoke ◽  
Wan Hasiah Abdullah ◽  
Mohammed Hail Hakimi
Keyword(s):  
Organic Matter ◽  
Upper Cretaceous ◽  
Hydrocarbon Generation ◽  
Hydrocarbon Generation Potential

Biomarker Geochemistry and Hydrocarbon Generation Potential of the Evaporites in Dongying Lacustrine Basin

2012 ◽  
Vol 616-618 ◽  
pp. 1042-1047
Author(s):  
Zhong Hong Chen
Keyword(s):  
Organic Matter ◽  
Hydrocarbon Generation ◽  
Lacustrine Basin ◽  
Hydrocarbon Generation Potential ◽  
Deep Wells ◽  
Generating Capacity ◽  
High Maturity ◽  
Different Response ◽  
Hydrocarbon Expulsion ◽  
Rock Eval

To investigate hydrocarbon potential of the evaporites, some deep wells such as Haoke-1 well and Fengshen-2 well were intensively cored, tested by TOC, Rock-Eval, and chromatography and mass spectrometry and evaluated using geochemistry of biomarker and hydrocarbon generation. High content of gammacerane and low Pr/Ph was exhibited in the evaporite system compared to the non-evaporite system. Different response of biomarkers parameters for the different sedimentary systems was exhibited, such as C19/(C19+C23) terpanes, C29/(C27+C28+C29) steranes, C24/C23 and C22/C21 tricyclic terpane. The evaporites and mud stones have the capacity to generate and expel hydrocarbons. The tested samples were mostly typeⅠand typeⅡ1 of organic matter, and their original generating capacity can reach 40 mg/g rock and 20 mg/g rock respectively. The efficiency of hydrocarbon expulsion reached 60%, but the distribution of organic matter and its generative potential was highly variable. In general, the mudstones show greater generative potential than the evaporites. High maturity severely reduced the capacity of their rocks to generate and expel petroleum.

scholarly journals Integration of the outcrop and subsurface geochemical data: implications for the hydrocarbon source rock evaluation in the Lower Indus Basin, Pakistan

2018 ◽  
Vol 9 (2) ◽  
pp. 937-951 ◽  
Author(s):  
Sajjad Ahmad ◽  
Faizan Ahmad ◽  
Abd Ullah ◽  
Muhammad Eisa ◽  
Farman Ullah ◽  
...  
Keyword(s):  
Organic Matter ◽  
Source Rock ◽  
Vitrinite Reflectance ◽  
Indus Basin ◽  
Hydrocarbon Generation ◽  
Type Ii ◽  
Hydrocarbon Source Rock ◽  
Hydrocarbon Generation Potential ◽  
Well Data

Abstract The present study details the hydrocarbon source rock geochemistry and organic petrography of the outcrop and subsurface samples of the Middle Jurassic Chiltan Formation and the Lower Cretaceous Sembar Formation from the Sann #1 well Central and Southern Indus Basin, Pakistan. The total organic carbon (TOC), Rock–Eval pyrolysis, vitrinite reflectance (Ro) % and Maceral analysis techniques were used and various geochemical plots were constructed to know the quality of source rock, type of kerogen, level of maturity and migration history of the hydrocarbons. The outcrop and Sann #1 well data on the Sembar Formation reveals poor, fair, good and very good quality of the TOC, type II–III kerogen, immature–mature organic matter and an indigenous hydrocarbon generation potential. The outcrop and Sann #1 well data on the Chiltan Formation show a poor–good quality of TOC, type II–III kerogen, immature–mature source rock quality and having an indigenous hydrocarbon generation potential. The vitrinite reflectance [Ro (%)] values and Maceral types [fluorescent amorphous organic matter, exinite, alginite and inertnite] demonstrate that maturity in both Sembar and the Chiltan formation at surface and subsurface fall in the oil and gas generation zone to cracking of oil to gas condensate zone. Recurrence of organic rich and poor intervals within the Sembar and Chiltan formation are controlled by the Late Jurassic thermal uplift preceding the Indo-Madagascar separation from the Afro-Arabian Plate and Early Cretaceous local transgressive–regressive cycles. From the current study, it is concluded that both Sembar and Chiltan formation can act as a potential hydrocarbon source rock in the study area.

scholarly journals Hydrocarbon source rock assessment of the shale and coal bearing horizons of the Early Paleocene Hangu Formation in Kala-Chitta Range, Northwest Pakistan

2022 ◽  
Author(s):  
Nasar Khan ◽  
Wasif Ullah ◽  
Syed M. Siyar ◽  
Bilal Wadood ◽  
Tariq Ayyub ◽  
...  
Keyword(s):  
Organic Matter ◽  
Source Rock ◽  
Liquid Hydrocarbon ◽  
Minor Amount ◽  
Hydrocarbon Generation ◽  
Thermal Maturity ◽  
Hydrocarbon Generation Potential ◽  
Stable Isotopic ◽  
Early Paleocene ◽  
Geochemical Analyses

AbstractThe present study aims to investigate the origin, type, thermal maturity and hydrocarbon generation potential of organic matter and paleo-depositional environment of the Early Paleocene (Danian) Hangu Formation outcropped in the Kala-Chitta Range of Northwest Pakistan, Eastern Tethys. Organic-rich shale and coal intervals were utilized for geochemical analyses including TOC (total organic carbon) and Rock–Eval pyrolysis coupled with carbon (δ13Corg) and nitrogen (δ15Norg) stable isotopes. The organic geochemical results showed that the kerogen Type II (oil/gas prone) and Type III (gas prone) dominate the investigated rock units. The TOC (wt%) and S2 yield indicate that the rock unit quantifies sufficient organic matter (OM) to act as potential source rock. However, the thermal maturity Tmax°C marks the over maturation of the OM, which may be possibly linked with the effect attained from nearby tectonically active Himalayan Foreland Fold-and-Thrust Belt system and associated metamorphosed sequences. The organic geochemical analyses deciphered indigenous nature of the OM and resultant hydrocarbons. The δ13Corg and δ15Norg stable isotopic signatures illustrated enrichment of the OM from both marine and terrestrial sources accumulated into the Hangu Formation. The Paleo-depositional model established using organic geochemical and stable isotopic data for the formation supports its deposition in a shallow marine proximal inner shelf environment with prevalence of sub-oxic to anoxic conditions, a scenario that could enhance the OM preservation. Overall, the formation holds promising coal and shale intervals in terms of organic richness, but due to relatively over thermal maturation, it cannot act as an effective source rock for liquid hydrocarbon generation and only minor amount of dry gas can be expected. In implication, the results of this study suggest least prospects of liquid hydrocarbon generation potential within Hangu Formation at studied sections.

scholarly journals Comparative Assessment of Hydrocarbon Generation Potential of Organic Matter from Shale Sediments along Isugwuato – Okigwe Axis, Anambra Basin, SE Nigeria

2021 ◽  
Vol 25 (3) ◽  
pp. 353-362
Author(s):  
M.U. Uzoegbu ◽  
C.U. Ugwueze
Keyword(s):  
Organic Matter ◽  
Oil And Gas ◽  
Oxygen Index ◽  
Hydrocarbon Generation ◽  
Hydrocarbon Generation Potential ◽  
Anambra Basin ◽  
Kerogen Type ◽  
Oil Generation ◽  
Carbonaceous Shales ◽  
Petroleum Generation

TRACT: The Cretaceous sediments in the Anambra Basin (SE Nigeria) consist of a cyclic succession of coals, carbonaceous shales, silty shales and siltstones  interpreted as deltaic deposits. The objective of this study is to compare the hydrocarbon generation potential of organic matter from shale sediments along Isugwuato-Okigwe axis in the Anambra Basin, Nigeria. Data obtained indicates the presence of Type III kerogen with Tmax values are between 424 and 441ºC indicating that the shales are thermally immature to marginally mature with respect to petroleum generation. Hydrogen Index (HI) values range from 14 to 388.9mgHC/gTOC while S1 + S2 yields values ranging from 0.2 to 1.0mgHC/g rock, suggesting that the shale have gas generating potential. The TOC values rangesfrom 1.3 to 3.0%, an indication of a good source rock of terrestrially derived organic matter. The high oxygen index (OI) (16.3 mgCO2g-1TOC), TS (1.35) and TOC/TS (1.5) suggest deposition in a shallow marine environment. Based on the kerogen type, shales from the studied area will equally generate oil and gas if its organic matter attained sufficient thermal temperature. Keywords: Shale, kerogen type, maturity, oil generation.

scholarly journals Source Rock Evaluation and Hydrocarbon Generation Model of a Permian Alkaline Lakes—A Case Study of the Fengcheng Formation in the Mahu Sag, Junggar Basin

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 644
Author(s):  
Yong Tang ◽  
Wenjun He ◽  
Yubin Bai ◽  
Xiang Zhang ◽  
Jingzhou Zhao ◽  
...  
Keyword(s):  
Organic Matter ◽  
Evaluation Criteria ◽  
Junggar Basin ◽  
Source Rocks ◽  
Geochemical Data ◽  
Generation Model ◽  
Hydrocarbon Generation ◽  
High Hydrocarbon ◽  
Hydrocarbon Generation Potential ◽  
Alkaline Lake

The alkaline lake source rocks of the Fengcheng Formation are developed in the Mahu Sag of the Junggar Basin. Different from traditional continental fresh water and saltwater lake source rocks, alkaline lake source rocks lack targeted evaluation criteria, and it is unknown whether their hydrocarbon generation models are consistent with traditional models. Therefore, in the present study, evaluation standards and hydrocarbon generation models of alkaline lake source rocks are discussed based on geological and organic geochemical data and a systematic summary of the geochemical characteristics of the Fengcheng Formation source rocks. The Fengcheng Formation source rocks are mainly diamictite with mixed argillaceous rock and dolomite; most total organic carbon (TOC) values range from 0.2–1.4%; and the kerogen is primarily oil-prone type II, reaching low- to high-maturity stages. Based on the types of organic matter in source rocks and the relationships between organic matter abundance parameters, the evaluation standard of alkaline lake source rocks is proposed. The Fengcheng Formation is mainly composed of good to excellent source rocks (55.5%) with high hydrocarbon generation potential. The single-peak hydrocarbon generation model of the Fengcheng Formation is similar to that of traditional freshwater or saltwater lakes, with a high hydrocarbon generation rate, two to five times that of the traditional model; its main particularity is in the formation of naphthenic crude oil from the kerogen of bacteria and algae. A new understanding of the hydrocarbon generation potential and model of alkaline lake source rocks in the Fengcheng Formation can provide support for tight oil and shale oil exploration in the Mahu Sag.

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