scholarly journals Organic geochemical characteristics and comparison of the source rocks and the severely biodegradable oil sands around Karamay, China

2020 ◽  
pp. 014459872096487
Author(s):  
Chong Feng ◽  
Wenjun He ◽  
Hua Cai ◽  
Jingyuan Zhang ◽  
Yinlan Nie
Keyword(s):  
Organic Carbon ◽  
Oil Sands ◽  
Geochemical Characteristics ◽  
Source Rocks ◽  
Gas Chromatography Mass Spectrometry ◽  
Mature Stage ◽  
Oil Sand ◽  
Core Samples ◽  
Tricyclic Terpanes ◽  
Almost All

For the sake of explaining the organic geochemical characteristics of the hydrocarbon source rocks (SRs) around Karamay, such as thermal maturity (TM) (evidences from the temperature of maximum pyrolysis yield (Tmax), the Carbon Preference Index (CPI) and Odd to Even Preference (OEP) values, the C30 M/H versus Tm/Ts, the C29 ββ/(ββ + αα) versus C29 20 S/(20 S + 20 R)), hydrocarbon potential (HP) (evidences from total organic carbon (TOC) and rock pyrolysis (RP)), organic matter (OM) source input (evidences from n-Alkane distribution, the relative quantity of C27-C28-C29 steranes, the (C19 + C20)/C23 tricyclic terpane (TT), and the Terrigenous/aquatic ratio (TAR)) as well as paleoenvironment (evidences from the pristane/phytane (Pr/Ph) and the Gammacerane index), and in order to analyze the biodegradation degree and source of oil sand (OS) oil, 55 core samples of SRs in all were selected to measure TOC and RP. 14 core samples of SRs and 3 OS samples were selected for gas chromatography–mass spectrometry (GC-MS) analysis. 11 core samples of SRs and 3 OS samples were used for organic carbon isotope (OCI) analysis. The results indicate that except the SR from Fengcheng formation (P1 f) which is in the stage of high or over evolution, the other SRs are in mature stage. OM type of Carboniferous (C) SRs are type Ⅱ kerogen, with the largest abundance. OM type of the SRs in Wuerhe formation (P2 w) and Jiamuhe formation (P1 j) are type Ⅲ kerogen with good and medium OM abundances. Almost all SRs were formed in the reduction environment of high salinity, and the main OM source input is the lower aquatic plants. Karamay formation (T2 k) and Badaowan formation (J1 b) oil sands (OSs) around Karamay have undergone serious biodegradation. It is suggested that OS oil are mainly from P1 f SRs (evidences from the tricyclic terpanes (TT), triarysteranes, pregnane, homopregnane and OCI).

scholarly journals 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 ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 439 ◽  
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.

scholarly journals Application of back-propagation neural networks in the distribution of oil sand reservoirs—a case study from the western slope of the Songliao Basin, China

2021 ◽  
Vol 14 (4) ◽  
Author(s):  
Jing Sun ◽  
Yuting Zhao ◽  
ChangQing Yang ◽  
Xuanlong Shan
Keyword(s):  
Neural Network ◽  
Bp Neural Network ◽  
Oil Sands ◽  
Back Propagation ◽  
Songliao Basin ◽  
Source Rocks ◽  
Western Slope ◽  
Oil Sand ◽  
Neural Network Method ◽  
Network Method

AbstractHigh-quality hydrocarbon source rocks are present in the upper Cretaceous layer in the western slope of the Songliao Basin. Oil and gas have accumulated in these rocks at the shallow edge of the basin, which has led to the formation of oil sand resources. This study uses the back-propagation (BP) neural network method to predict the distribution of oil sand reservoirs and is the first study of its kind in China. First, based on the basic data collected by core sample, well log and geochemical analyses, and the reasonable selection of samples, the cores are divided into mudstone, siltstone, fine sandstone, medium sandstone, and sand, according to lithology. Second, a three-layer BP neural network model is constructed with two hidden S-type layers and one linear output layer. Third, through a comparison of the effect of different numbers of training sessions of the sample data, we demonstrate that the accuracy of the model can be increased to 90% after training the network 100,000 times. Then, the log-derived data of rocks with unknown lithologies are input into the neural network to predict whether they contain oil sands. We show that the BP neural network method can predict the distribution of oil sand reservoirs in the target horizon of the study area, and the results are consistent with research results on the corresponding sand reservoirs and sedimentary facies. Thus, we conclude that it is feasible to use the BP neural network method to predict the distribution of oil sand reservoirs.

Oil Sands Forming Model of the Northwest Edge of the Junggar Basin, China

2015 ◽  
Vol 1092-1093 ◽  
pp. 1430-1435
Author(s):  
Qun Zhao ◽  
Hong Yan Wang ◽  
De Xun Liu ◽  
Shen Yang ◽  
Dong Mei Luo
Keyword(s):  
Oil Sands ◽  
Junggar Basin ◽  
Sedimentary Facies ◽  
Source Rocks ◽  
Alluvial Fans ◽  
Tectonic Movement ◽  
Oil Sand ◽  
Oil Viscosity ◽  
Multi Phase ◽  
Abundance And Distribution

The Junggar Basin has the basic conditions for giant oil-sand mine to form and it is the hot point for exploration and development of oil sands. Multi-layer source rocks deposited in the Manas Lake Depression have produced abundant hydrocarbon in the course of multi-phase tectonic movement and they were the source of oil sands. Many unconformities formed also in the course of multi-phase tectonic movement were the main pathway of lateral movement of hydrocarbon and the well-developed abnormal faults were the main vertical pathway. The sands bodies of fluvial facies in alluvial fans in front of the Zhair Mountain offered a very favorable reservoirs for oil-sand mine. Hard biodegradation make the viscosity of hydrocarbon heavier and heavier. The hydrocarbon seized on the surface of sands, and then oil sands were formed. The peculiar characters of the northwest edge of the Junggar Basin make the oil sands occur at the compressive side of the basin. And the lateral distribution of oil sands mine is bigger and the scale is smaller relatively. The fault’ openness, fossil landscape, sedimentary facies, oil viscosity have controlled the abundance and distribution of oil sands.

scholarly journals The geochemical and organic petrological characteristics of coal measures of the Xujiahe formation in the Sichuan Basin, China

2019 ◽  
Vol 37 (3) ◽  
pp. 889-906 ◽  
Author(s):  
Guoxiao Zhou ◽  
Guoqi Wei ◽  
Guoyi Hu
Keyword(s):  
Gas Chromatography ◽  
Organic Carbon ◽  
Sichuan Basin ◽  
Sea Water ◽  
Source Rocks ◽  
Gas Chromatography Mass Spectrometry ◽  
Organic Carbon Content ◽  
Hydrocarbon Generation ◽  
Adsorption Effect ◽  
Xujiahe Formation

Upper Triassic coaly and lacustrine source rocks complicate efforts to determine the source of hydrocarbons in Sichuan Basin. Total organic carbon analyses, pyrolysis experiments, petrological examinations, and gas chromatography and gas chromatography–mass spectrometry determinations were conducted on coals, carbonaceous mudstones and mudstones collected from two outcrop sections and cores of nine wells. Results revealed that the abundant organic carbon content will prolong the hydrocarbon generation cycle for coals and then the hydrocarbon generating capacity of coals will be enhanced by salinization, thereby contributing bacteria and algae microorganisms into humic coal of the Xujiahe Formation. Compared with mudstone, coal with the same maturity has a stronger adsorption effect on free hydrocarbons. When Ro is greater than 1.35, coal still has a strong hydrocarbon generation ability. The stable water column stratification and euxinic bottom water conditions are evidenced from the lower Pr/Ph and the higher gammacerane indices. The mixing of sea water has been proven by the existence of 4α,23,24,-trimethylcholestanes.

scholarly journals Geochemical Characteristics of Released Organic Matters by Acid Decomposition of Hydrocarbon Source Rocks from Different Sedimentary Basins

Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Peng Liu ◽  
Xiaofeng Wang ◽  
Xiaofu Li ◽  
Ting Zhang ◽  
Wenhui Liu
Keyword(s):  
Organic Carbon ◽  
Acid Solution ◽  
Total Organic Carbon ◽  
Acid Treatment ◽  
Geochemical Characteristics ◽  
Source Rocks ◽  
Hydrocarbon Generation ◽  
Carbonate Minerals ◽  
Important Indicator ◽  
Organic Matters

It has been acknowledged that carbonate was identified as the source rocks of a series of oil-gas fields worldwide. For evaluating the carbonate source rocks, total organic carbon (TOC) contents act as an important indicator. However, the acid solution, which has been generated during conventional TOC measurements, contain organic matters. Hence, the released organic matters in acid solution during carbonate decomposition may lead to underestimate the hydorcarbon generation potential. In this study, rock-eval pyrolysis technique was applied to bulk rock and residue after acid treatment. Meanwhile, the organic matters in acid solution were measured by Gas Chromatography-Mass Spectrometer (GC-MS) to investigate the geochemical characteristics. In addition, the hydrocarbon generation and alteration of TOC contents of released organic matters by acid treatment were studied by hydrous pyrolysis experiments. The results show that the acid solution contains organic compounds, including n-alkanes, saturated fatty acids and fatty acid methyl esters. Meanwhile, total organic carbon (TOC) contents and hydrocarbon generation potential (S1+S2) significantly decrease for bulk rocks after acid treatment in low maturity samples. Moreover, organic CO2 (S3) decreased after treating of acid, revealing that acidolysis process can affect and release organic matters containing oxygen-bearing functional groups. The S1, S2, S3, and TOC loss are positive correlation with the proportion of rock loss during acidolysis, indicating that the organic matters in acid solution are associated with carbonate minerals. The organic fractions may exist as adsorption state on the surface of carbonate minerals and (or) exist as organic acid salts. Moreover, the thermal simulation experiments reveal that the organic matter in acid solution, which is not recovered by the conventional measurement approach, could contribute to hydrocarbon generation.

scholarly journals Geochemical Characteristics and Origins of the Crude Oil of Triassic Yanchang Formation in Southwestern Yishan Slope, Ordos Basin

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Xiaoli Zhang ◽  
Jinxian He ◽  
Yande Zhao ◽  
Hongchen Wu ◽  
Zeqiang Ren
Keyword(s):  
Crude Oil ◽  
Oil And Gas ◽  
Saturated Hydrocarbon ◽  
Ordos Basin ◽  
Water Environment ◽  
Geochemical Characteristics ◽  
Source Rocks ◽  
Gas Chromatography Mass Spectrometry ◽  
Yanchang Formation ◽  
Parent Materials

Biomarker compounds that derived from early living organisms play an important role in oil and gas geochemistry and exploration since they can record the diagenetic evolution of the parent materials of crude oil and reflect the organic geochemical characteristics of crude oil and source rocks. To offer scientific basis for oil exploration and exploitation for study area, gas chromatography-mass spectrometry method is applied to study the biomarker compounds of crude oil in Southwestern Yishan Slope of Ordos Basin, through qualitatively and quantitatively analyzing separated materials. The crude oil of Yanchang Formation and the source rocks of Yan’an and Yanchang Formation were collected in order to systematically analyze the characteristics of the biomarker compounds in saturated hydrocarbon fractions and clarify the organic geochemical characteristics of crude oil. The distribution and composition of various types of hydrocarbon biomarker compounds in crude oil suggest that the parent materials of crude oil are composed of hydrobiont and terrigenous plants, and the crude oil is mature oil which is formed in the weak reducing fresh water environment. Oil source correlation results show that the crude oil of Yanchang Formation in Yishan Slope is sourced from the source rocks of Chang 7 subformation.

CHARACTERISATION OF DISSOLVED ORGANIC CARBON (DOC) LEACHED FROM LEAVES IN WATER

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Markus Heryanto Langsa
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Total Organic Carbon ◽  
Gas Chromatography Mass Spectrometry ◽  
Pyrolysis Gas ◽  
Pyrolysis Gas Chromatography ◽  
Chromatography Mass Spectrometry ◽  
Pinus Radiate

<p>Penelitian ini bertujuan untuk menentukan senyawa organik khususnya organic karbon terlarut (DOC) dari dua spesies daun tumbuhan (<em>wandoo eucalyptus </em>and <em>pinus radiate, conifer</em>) yang larut dalam air selama periode 5 bulan leaching eksperimen. Kecepatan melarutnya senyawa organic ditentukan secara kuantitatif dan kualitatif menggunakan kombinasi dari beberapa teknik diantaranya Total Organic Carbon (TOC) analyser, Ultraviolet-Visible (UV-VIS) spektrokopi dan pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS).</p><p>Hasil analisis DOC dan UV menunjukkan peningkatan yang tajam dari kelarutan senyawa organic di awal periode pengamatan yang selanjutnya berkurang seiring dengan waktu secara eksponensial. Jumlah relatif senyawa organic yang terlarut tergantung pada luas permukaan, aktifitas mikrobiologi dan jenis sampel tumbuhan (segar atau kering) yang digunakan. Fluktuasi profil DOC dan UV<sub>254</sub> disebabkan oleh aktifitas mikrobiologi. Diperoleh bahwa daun kering lebih mudah terdegradasi menghasilkan senyawa organic dalam air dibandingkan dengan daun segar. Hasil pyrolysis secara umum menunjukkan bahwa senyawa hidrokarbon aromatic dan fenol (dan turunannya) lebih banyak ditemukan pada residue sampel setelah proses leaching kemungkinan karena adanya senyawa lignin atau aktifitas humifikasi mikrobiologi membuktikan bahwa senyawa-senyawa tersebut merupakan komponen penting dalam proses karakterisasi DOC.</p>

Stratigraphic Intervals for Oil and Tar Sand Deposits in the Uinta Basin, Utah

2017 ◽  
Vol 54 (4) ◽  
pp. 227-264
Author(s):  
Ronald Johnson ◽  
Justin Birdwell ◽  
Paul Lillis
Keyword(s):  
Brackish Water ◽  
Source Rocks ◽  
Uinta Basin ◽  
Green River ◽  
Reservoir Rocks ◽  
Stratigraphic Framework ◽  
Two Samples ◽  
The Rich ◽  
And Migration ◽  
Almost All

To better understand oil and bitumen generation and migration in the Paleogene lacustrine source rocks of the Uinta Basin, Utah, analyses of 182 oil samples and tar-impregnated intervals from 82 core holes were incorporated into a well-established stratigraphic framework for the basin. The oil samples are from the U.S. Geological Survey Energy Resources Program Geochemistry Laboratory Database; the tar-impregnated intervals are from core holes drilled at the Sunnyside and P.R. Spring-Hill Creek tar sands deposits. The stratigraphic framework includes transgressive and regressive phases of the early freshwater to near freshwater lacustrine interval of Lake Uinta and the rich and lean zone architecture developed for the later brackish-to-hypersaline stages of the lake. Two types of lacustrine-sourced oil are currently recognized in the Uinta Basin: (1) Green River A oils, with high wax and low β-carotane contents thought to be generated by source rocks in the fresh-to-brackish water lacustrine interval, and (2) much less common Green River B oils, an immature asphaltic oil with high β-carotane content thought to be generated by marginally mature to mature source rocks in the hypersaline lacustrine interval. Almost all oil samples from reservoir rocks in the fresh-to-brackish water interval are Green River A oils; however four samples of Green River A oils were present in the hypersaline interval, which likely indicates vertical migration. In addition, two samples of Green River B oil are from intervals that were assumed to contain only Green River A oil. Tar sand at the P.R. Spring-Hill Creek deposit are restricted to marginal lacustrine and fluvial sandstones deposited during the hypersaline phase of Lake Uinta, suggesting a genetic relationship to Green River B oils. Tar sand at the Sunnyside deposit, in contrast, occur in marginal lacustrine and alluvial sandstones deposited from the early fresh to nearly freshwater phase of Lake Uinta through the hypersaline phase. The Sunnyside deposit occurs in an area with structural dips that range from 7 to 14 degrees, and it is possible that some tar migrated stratigraphically down section.

Sign in / Sign up

Export Citation Format

Share Document