scholarly journals Direct signs of oil-generation in the rocks of Bazhenov Suite

Georesursy ◽  
2021 ◽  
Vol 23 (2) ◽  
pp. 152-157
Author(s):  
Natalia V. Pronina ◽  
Anastasiya P. Vaitekhovich
Keyword(s):  
Organic Matter ◽  
Oil And Gas ◽  
Secondary Porosity ◽  
Organic Petrology ◽  
Oil Generation ◽  
Microscopic Studies ◽  
Oil Source ◽  
Coal Petrography ◽  
Long Term Studies

Nowadays, the term “organic petrology” is widely used for the microscopic study of the organic matter (OM) of rocks. In the world, there are a large number of articles describing organic macerals in regions where shale oil and gas are produced. It is no coincidence that the new term “organic petrology” appeared instead of “coal petrography” since new macerals were found and described in the dispersed organic matter. So, along with alginites (previously the only term describing the oil-source sapropel-type OM), bituminite and bitumen appeared. Bituminite is heterogeneous, so it has varieties as “post-mature bituminite” and “atypical bituminite”. One of the typical components of the Bazhenov formation, along with described above, are the remains of soft radiolarians bodies. All of these organic macerals have a similar reflectance index with small differences. Long-term studies of the OM rocks of the West Siberian basin have revealed indications of oil generation, which are easily established by standard microscopic studies. These indications include a change in the colour of macerals, a different glow of oil-source components (all from the liptinite group), the appearance of bitumen films, the appearance of post-mature bituminite, the appearance of secondary porosity.

PETROLEUM SOURCE ROCKS IN THE ROPER GROUP OF THE MCARTHUR BASIN: SOURCE CHARACTERISATION AND MATURITY DETERMINATIONS USING PHYSICAL AND CHEMICAL METHODS

1994 ◽  
Vol 34 (1) ◽  
pp. 279 ◽  
Author(s):  
Dennis Taylor ◽  
Aleksai E. Kontorovich ◽  
Andrei I. Larichev ◽  
Miryam Glikson
Keyword(s):  
Organic Matter ◽  
Chemical Evolution ◽  
Oil And Gas ◽  
Source Rocks ◽  
Type I ◽  
Peak Oil ◽  
Gas Generation ◽  
Oil Generation ◽  
Physical And Chemical ◽  
Extractable Organic Matter

Organic rich shale units ranging up to 350 m in thickness with total organic carbon (TOC) values generally between one and ten per cent are present at several stratigraphic levels in the upper part of the Carpentarian Roper Group. Considerable variation in depositional environment is suggested by large differences in carbon:sulphur ratios and trace metal contents at different stratigraphic levels, but all of the preserved organic matter appears to be algal-sourced and hydrogen-rich. Conventional Rock-Eval pyrolysis indicates that a type I-II kerogen is present throughout.The elemental chemistry of this kerogen, shows a unique chemical evolution pathway on the ternary C:H:ONS diagram which differs from standard pathways followed by younger kerogens, suggesting that the maturation histories of Proterozoic basins may differ significantly from those of younger oil and gas producing basins. Extractable organic matter (EOM) from Roper Group source rocks shows a chemical evolution from polar rich to saturate rich with increasing maturity. Alginite reflectance increases in stepwise fashion through the zone of oil and gas generation, and then increases rapidly at higher levels of maturation. The increase in alginite reflectance with depth or proximity to sill contacts is lognormal.The area explored by Pacific Oil and Gas includes a northern area where the Velkerri Formation is within the zone of peak oil generation and the Kyalla Member is immature, and a southern area, the Beetaloo sub-basin, where the zone of peak oil generation is within the Kyalla Member. Most oil generation within the basin followed significant folding and faulting of the Roper Group.

The role of long-term sites in agroecological research: A case study

1995 ◽  
Vol 75 (1) ◽  
pp. 123-133 ◽  
Author(s):  
H. H. Janzen
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Management Practices ◽  
Cropping Systems ◽  
Simulation Models ◽  
Sample Collection ◽  
Productivity Measurement ◽  
Sampling Protocols ◽  
Long Term Studies

Gradual, episodic or subtle changes in agroecosystems can be definitively measured only in long-term studies. The objective of this paper is to illustrate the benefits and limitations of long-term agroecological sites using a crop rotation study (Rotation ABC) established at Lethbridge, Alberta in 1910. Long-term agroecological sites, envisioned as part of a continuum of research levels, seek to determine the persistence of cropping systems with respect to their effects on soil resources and the larger environment. Examples of research findings arising from such sites include the documentation of long-term changes in agricultural productivity, measurement of organic matter changes over time, calculation of long-term nutrient budgets, and verification of simulation models. For example, soil organic matter concentrations in Rotation ABC were found to decline abruptly within the first few decades of cultivation and then approach a new steady state. Despite the continual removal of N in harvested grain, soil N concentrations also appear to have stabilized, suggesting an accession of N approximately equivalent to the amount harvested. Common limitations of long-term sites like that at Lethbridge include: rudimentary experimental design, evolving management practices, incidental changes at the sites, and variation in sampling protocols. The successful use of long-term agroecological sites depends on well-defined objectives, simplicity of design, adequate scale, consistent data and sample collection, and collaboration among sites. The primary justification for the establishment and maintenance of long-term agroecological sites may be their future role in answering questions not yet envisioned. Key words: Soil organic matter, long-term studies, crop rotations, sustainability, fertilizer

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 Geochemistry of natural gases from sediments of terrigenous and carbonate formations of the Bukhara-Khiva oil and gas region of Uzbekistan

2021 ◽  
Vol 937 (4) ◽  
pp. 042085
Author(s):  
N Mukhutdinov ◽  
I Khalismatov ◽  
N Akramova ◽  
R Zakirov ◽  
A Zakirov ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Sulfide ◽  
Oil And Gas ◽  
Natural Gases ◽  
Marine Carbonate ◽  
Predictive Assessment ◽  
Carbonate Formations ◽  
Hydrocarbon Deposits ◽  
Long Term Studies

Abstract The results of long-term studies of natural gases in the Bukhara-Khiva oil and gas region of Uzbekistan are summarized. The results of studying the composition of gases in hydrocarbon deposits generated by OM of continental (terrigenous deposits of the Cretaceous and Middle Jurassic) and marine (carbonate Jurassic) facies are presented. Regularities of changes in individual constituents of gases (hydrocarbons, hydrogen sulfide, carbon dioxide, nitrogen, etc.) with depth are considered; the influence exerted on the composition of gases by various factors and, above all, those of them, which, in the opinion of most researchers, are the main ones. The revealed patterns are used for predictive assessment of the distribution of various constituents of natural gases in the study area.

HYDROCARBON GENERATION, MIGRATION AND ENTRAPMENT IN THE JACKSON-NACCOWLAH AREA, ATP 259P, SOUTHWESTERN QUEENSLAND

1985 ◽  
Vol 25 (1) ◽  
pp. 62 ◽  
Author(s):  
P.W. Vincent I.R. Mortimore ◽  
D.M. McKirdy
Keyword(s):  
Oil And Gas ◽  
Source Rocks ◽  
Hydrocarbon Generation ◽  
Structural Development ◽  
Southeastern Part ◽  
Gas Field ◽  
Early Tertiary ◽  
Oil Generation ◽  
Oil Source ◽  
Eromanga Basin

The northern part of the Naccowlah Block, situated in the southeastern part of the Authority to Prospect 259P in southwestern Queensland, is a major Eromanga Basin hydrocarbon province. The Hutton Sandstone is the main reservoir but hydrocarbons have been encountered at several levels within the Jurassic-Cretaceous sequence. In contrast, the underlying Cooper Basin sequence is generally unproductive in the Naccowlah Block although gas was discovered in the Permian at Naccowlah South 1. Oil and gas discoveries within the Eromanga Basin sequence are confined to the Naccowlah-Jackson Trend. This trend forms a prominent high separating the deep Nappamerri Trough from the shallower, more stable northern part of the Cooper Basin.The Murta Member is mature for initial oil generation along the Naccowlah-Jackson Trend and has sourced the small oil accumulations within this unit and the underlying Namur Sandstone Member. The Birkhead Formation is a good source unit in this area with lesser oil source potential also evident in the Westbourne Formation and 'basal Jurassic'. Source quality and maturation considerations imply that much of the oil discovered in Jurassic reservoirs along the Naccowlah-Jackson Trend was generated from more mature Jurassic source beds in the Nappamerri Trough area to the southwest. Maturation modelling of this deeper section suggests that hydrocarbon generation from Jurassic source units commenced in the Early Tertiary. Significant oil generation and migration has therefore occurred since the period of major structural development of the Naccowlah-Jackson Trend in the Early Tertiary. This trend, however, has long been a major focus for hydrocarbon migration paths out of the Nappamerri Trough as a result of intermittent structuring during the Mesozoic. Gas reservoired in Jurassic sandstones at Chookoo has been generated from more mature Jurassic source rocks in the deeper parts of the Nappamerri Trough.Permian sediments in the Nappamerri Trough area are overmature for oil generation and are gas prone. Gas generated in this area has charged the lean Permian gas Field at Naccowlah South, along the Wackett-Naccowlah- Jackson Trend. North of this trend Permian source rocks are mainly gas prone but more favourable levels of maturity allow the accumulation of some gas liquids and oil. However, geological and geochemical evidence suggests that Permian sediments did not source the oil found in Jurassic-Cretaceous reservoirs in the Jackson- Naccowlah area.

NEW LIGHT ON THE ORIGIN OF COOPER BASIN OIL

1988 ◽  
Vol 28 (1) ◽  
pp. 303 ◽  
Author(s):  
G.H.Taylor G.H.Taylor ◽  
Susie Y. Liu ◽  
Michelle Smyth
Keyword(s):  
Organic Matter ◽  
Light Microscope ◽  
Oil And Gas ◽  
Close Association ◽  
Source Rocks ◽  
Transmission Electron ◽  
Oil Generation ◽  
Terrestrial Sediments ◽  
Major Producer ◽  
Cooper Basin

The Cooper Basin in central Australia is a major producer of gas and oil. It is generally accepted that the organic matter in the Permian terrestrial sediments of the Basin was the source of the oil and gas. However, both the coals and the dispersed organic matter (DOM) are rich in inertinite and both inertinite itself and inertinite-rich organic matter have been widely discounted as a possible source for oil.Recent co-ordinated transmission electron microscope and light microscope work on the inertiniterich coals of the Cooper Basin has shown that up to several per cent of some coal samples are composed of microscopic and sub-microscopic alginite. This includes material that had previously been identified with the light microscope alone as degraded sporinite, liptodetrinite or resinite, as well as algal-derived matter, which is too fine to observe with light microscopy. Much of this material of algal origin was selectively degraded at about the time of its deposition, and this degradation appears likely to have had the effect of further enhancing its potential to yield hydrocarbons. Thus, such material should be ranked among the richest potential sources of hydrocarbons when appropriate diagenetic conditions have been attained. Since inertinite and this kind of alginite occur in particularly close association, the presence of inertinite-rich coals and DOM within potential source rocks should be regarded as a highly favourable rather than an unfavourable, indication (as in the past).The quantity of alginite in the very large volumes of inertinite-rich coal in the Basin is more than adequate to account for the oil accumulations. In the Cooper Basin the coals, rather than the DOM, had the better potential for oil generation.

scholarly journals Anti-erosion technology of potatoes irrigation on typical Chirchik-Angren valley serosemes

2020 ◽  
Vol 175 ◽  
pp. 01018
Author(s):  
Dilshod Nazaraliev ◽  
Shamshodbek Akmalov
Keyword(s):  
Organic Matter ◽  
Total Nitrogen ◽  
Economic Efficiency ◽  
Growth And Development ◽  
Water Efficiency ◽  
Irrigation Technology ◽  
The Law ◽  
Long Term Studies

The article deals with the results of the analysis of long-term studies on the study of soil-protective, water efficiency technologies for the cultivation of crops on eroded soils. For the conditions of irrigated and erosion impacted typical loamy soils of a Chirchik-Angren valley, the law of a pliability of the typical loamy soils impacted by erosion is revealed depening on the form of furrows and the size of a jet. The optimum forms of the furrow and size of a jet are determined for condition of typical loamy soils at growing potatoes. The influence of the form of furrow on the contents of organic matter, total nitrogen, common phosphorus in a liquid and firm drain is established the losses of nutritious substances with a liquid and firm drain are revealed depending on elements of irrigation technology. The growth and development of the potatoes is studied. The economic efficiency is determined at cultivation of a potatoes on typical erosion demaged loamy soils.

Long-term studies of the influence of invertebrate manipulations and drought on particulate organic matter export from headwater streams

1991 ◽  
Vol 24 (3) ◽  
pp. 1676-1680
Author(s):  
J. B. Wallace ◽  
T. F. Cuffney ◽  
B. S. Goldowitz ◽  
K. Chung ◽  
G. J. Lugthart
Keyword(s):  
Organic Matter ◽  
Particulate Organic Matter ◽  
Headwater Streams ◽  
Long Term Studies

scholarly journals Maturity of dispersed organic matter in bituminous formations of the Ionian Zone (Epirus region, NW Greece)

2017 ◽  
Vol 47 (2) ◽  
pp. 880
Author(s):  
D. Rallakis ◽  
G. Siavalas ◽  
G. Oskay ◽  
D. Tsimiklis ◽  
K. Christanis
Keyword(s):  
Organic Matter ◽  
Vitrinite Reflectance ◽  
Lower Jurassic ◽  
Source Rocks ◽  
Organic Petrology ◽  
Bituminous Shale ◽  
Petroleum Generation ◽  
Posidonia Shale ◽  
Rock Eval ◽  
Coal Petrography

The main objective of this paper is to study by means of Organic Petrology techniques, the maturity of the dispersed organic matter from certain sedimentary formations of the Ionian Zone, such as the Bituminous Shale, the Upper Siliceous Vigla Formation and the Bituminous Sandstone. The samples were collected from outcropping sites located in the region of Epirus. Initially they were treated with acids (HCl-HF) to remove most of the carbonate and silicate minerals. Then a ZnCl2 solution was used to concentrate the organic-rich fraction. Total Organic Carbon (TOC) content was determined applying dichromate oxidation. Polished blocks were prepared from the concentrated organic matter mounted in epoxy resin and examined under the coal-petrography microscope. Emphasis was given to maceral identification and vitrinite reflectance (R) measurements, which provide information regarding the quality and the maturity of the organic matter respectively, with implications for the petroleum generation potential regardless the level of alteration. The TOC and Rr values (4.74% and 0.68%, respectively) confirm to the oil potential of the Lower Jurassic Posidonia Shale. Nevertheless, it is suggested that detailed and higher resolution sampling focusing on the Lower Posidonia Shale, as well as organic petrography analyses coupled with Rock-Eval pyrolysis should be carried out in order to accurately determine its quality as petroleum source rocks.

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