scholarly journals Macerals Analysis Seam M2 Muaraenim Formation, : Implication Toward Coal Facies and Coal Rank in Kendi Hill, South Sumatra

2018 ◽  
Vol 3 (2) ◽  
pp. 94 ◽  
Author(s):  
Yonathan Mangatur Rajagukguk ◽  
Stevanus Nalendra Jati
Keyword(s):  
Coal Seam ◽  
Selection Process ◽  
Vitrinite Reflectance ◽  
Research Area ◽  
Mineral Matter ◽  
Coal Seams ◽  
Delta Plain ◽  
Southern Central ◽  
Coal Facies ◽  
Index Value

The Muaraenim Formation is a coal bearing formation in South Sumatra Basin of the Late Miocene – Pliocene. Shell (1978) divides this formation based on coal seam content are: M1, M2, M3, and M4. Coal seam in this area include in seam M2 member, with the general characteristics of the presence of silicified coal on the roof and floor of coal seams as a marker. The administration of the research area is located in east Kendi Hill, South Sumatra. The Kendi Hill is composed of adesite igneous rocks that intruded Muaraenim Formation in unconformity at the time of Pleistocene. This study aims to determine the environment of coal depositional based on maceral analysis and determine the factors influence the physical characteristics of coal seams in Kendi Hill. Data that has been obtained from the field, then conducted a selection process. The number of samples analyzed were  nine sample based on near and far to the Kendi Hill spread from the southern, central, and northern of the location. The  result of the analysis will display the maceral diagram. Megascopically, coal seam in the Kendi Hill are black, dull with bright, uneven – subchoncoidal, blackish brown in streak, have a pyrite and resin. The thickness of the coal seams ranges from 0,45 to 14 meters. Based on the maceral analysis, the coal seam in the Muaraenim Formation is composed dominated by vitrinite, then liptinite, inertinite and mineral matter pyrite (1,6-6,6%). Vitrinite reflectance of coal in the research area ranges from (0,37-0,48%) that included to the Sub bituminous – High Volatile Bituminous C. From the results of Tissue Preservation Index and Gelification Index value indicated that the environment of coal depositional in the research area was a limnic to wet forest swamp. Whereas the deposition of the Muaraenim Formation in deltaic environment (Transitional lower delta  plain).

scholarly journals Construct a Paleo-Limnological Environment Based on Coal Petrography; Case Study, Two Selected Coal Seams, North Crowsnest Open-Pit Mine, Canada

2021 ◽  
Vol 54 (2D) ◽  
pp. 1-14
Author(s):  
Nader A.A. Edress
Keyword(s):  
Coal Seam ◽  
Vegetation Index ◽  
Vitrinite Reflectance ◽  
Open Pit ◽  
Petrographic Analysis ◽  
Coal Seams ◽  
Water Index ◽  
Average Value ◽  
Coal Facies ◽  
Coal Petrography

The Crowsnest coalfield is a separated structural coalfield at the East Kootenay basin within southeast British Columbia. Selected Jurassic-Cretaceous two coals seam S-10 and S-C of the Mist-Mountain formation were investigated from the points of coal petrography to construct a Paleo-limnological setting. Twenty-two channel coal samples were assembled and measured from S-10 and S-C coal seams. Vitrinite reflectance measuring of the S-10 coal concern to low-volatile bituminous (1.61, on average). While the vitrinite reflectance measurements of S-C coal seam show an average value of 0.98 related to high-volatile bituminous. Petrographic analysis demonstrates that the S-10 coal seam appears to be rich in inertinite than the S-C coal seam that appears rich in vitrinite. Applying coal facies indices of Tissue Preservation Index, Gelification Index, Ground Water Index Vegetation Index and coal facies diagrams for the studied coal seams aid to suggest a condition of the depositional Paleo-environments. The results promote Paleo-depositional sites of telmatic to limno-telmatic setting of rheotropic systems swamp. The obtained results show a trend of increase in both herbaceous flora and anoxic waterlogged limo-telmatic setting toward the younger coal seam S-C than the older S-10 coal seam.

scholarly journals Characteristics of Coal and Cleat Attributes in Ulak Lebar and Surroundings Area, Lahat Regency, South Sumatra

2018 ◽  
Vol 3 (2) ◽  
pp. 116
Author(s):  
Mutia Armilia Rahmawati ◽  
Siska Linda Sari ◽  
Alan Triyoga ◽  
Idar Wati
Keyword(s):  
Coal Seam ◽  
Laboratory Test ◽  
Vitrinite Reflectance ◽  
Research Area ◽  
Test Field ◽  
Field Observations ◽  
Literature Study ◽  
Structure Control ◽  
Geological Processes ◽  
Significant Difference

The research conducted in Ulak Lebar Area, Lahat Regency, South Sumatra. The focus of this study is on the Muara Enim Formation as it is known as the main coal-bearing formation in South Sumatra Basin. The research is aimed to determine the characteristics of coal based on its physical properties, also knowing the cleat development at the coal seam in the research area. The methods used such as literature study, field observation and laboratory test. Field observations included the observations of coal megascopic appearance and cleat attributes analysis such as the measurements of cleat orientation, aperture, spacing and length. The analysis result of cleat at LP 2A and LP 2B shows a relatively similar such as spacing value ranged between 6 - 9 cm and 5.5 – 8.6 cm while the aperture value ranged from 0.05 - 0.2 cm, and 0.05 - 0.25 cm, whereas at LP 67 the spacing value ranged from 1.5 to 3.3 cm and the aperture valued between 0.1 - 0.3 cm. A rather significant difference between the cleat spacing values of LP 67 towards both previous observation stations is indicated by the geological processes occurred during the coalification process thus affected the development of cleats in coal, the geology structure control is characterized by a relatively large aperture and smaller spacing values. The laboratory test conducted is maceral analysis, shows the coal in the research area is dominantly composed of vitrinite (74,8%) and the vitrinite reflectance value is 0,40 indicating the coal classified as sub-bituminous rank.

scholarly journals Sedimentary system and coal seam distribution in the coal-bearing sequence stratigraphic framework in the Paleogene Meihe Formation (Meihe Basin, NE China)

2020 ◽  
Author(s):  
Yueyue Bai ◽  
Qingtian Lv ◽  
Zhaojun Liu ◽  
Pingchang Sun ◽  
Rong Liu ◽  
...  
Keyword(s):  
Coal Seam ◽  
Accumulation Rate ◽  
Mapping Method ◽  
Sediment Supply ◽  
Coal Seams ◽  
Delta Front ◽  
Contour Maps ◽  
Delta Plain ◽  
Fan Delta ◽  
Wide Range

Abstract The Meihe Basin is one of the important Paleogene coal-bearing fault basins of northeastern China in the Dunhua-Mishan Fault Zone. The Lower Coal-bearing Member and the Upper Coal-bearing Member are the primary layers studied. Through field observation, core description and observation under microscope, fan delta facies and lake facies are observed as the main sedimentary facies of the coal-bearing layers, and subfacies of fan delta plain, fan delta front, shallow lake and swamp have also been recognized. Coal seams primarily accumulated in the subfacies of swamp and fan delta plain. The study on sequence stratigraphy is based on outcrop section, well-log analysis, core observation and geochemical analysis. From the Lower Coal-bearing Member to the Upper Coal-bearing Member, three third-order sequences have been recognized; the Lower Coal-bearing Member developed in Sequence I and the Upper Coal-bearing Member developed in Sequence III, both sequences have developed the lowstand systems tract (LST), the transgressive systems tract (TST) and the highstand systems tract (HST). Single-factor analysis and the multifactor comprehensive mapping method have been used to rebuild the lithofacies palaeogeography of each system tract in Sequence I and Sequence III. Through analysis of contour maps of total stratum thickness, sandstone thickness and sand content, as well as contour maps of thicknesses and numbers of layers of coal seams, the results indicate that the sedimentary environments and coal seam distributions are variable in different system tracts. Coal types accumulating in the swamp facies are primarily developed in the transgressive systems tract (TST) and the highstand systems tract (HST) of Sequence I with a wide range of continuous and large thicknesses and may be mined commercially. Both the balanced accommodation growth rate with peat accumulation rate and little or no influence from sediment supply and channel migration promote to form the stable coal accumulating environments.

scholarly journals Vertical and lateral variation of gas content associated with coal seams

2015 ◽  
pp. 49-59
Author(s):  
Luis D. Caro ◽  
Astrid Blandón ◽  
Jorge M. Molina
Keyword(s):  
Coal Seam ◽  
Bituminous Coal ◽  
Direct Relationship ◽  
Vitrinite Reflectance ◽  
Gas Content ◽  
Lateral Variation ◽  
Coal Seams ◽  
Content Variation ◽  
Geological Factors ◽  
Proximal Analysis

Vertical and lateral gas content variation associated within a coal seam and its relation to porosity and geology was researched. Several seams of high sub-bituminous and bituminous coal volatile C from Amaga formation were selected. Channel samples were taken and were subdivided into the different plies (lithotypes associations), performing proximal analysis; Petrographic (maceral counting and determining the vitrinite reflectance); furthermore desorption testing and porosity.The higher gas content was in intermediate plies. It was possible to identify that the gas content, and micropores and mesopores has a direct relationship; also, there is a direct relationship between the content of liptinites macerals and gas content. In some cases, these relationships were not clear, since there is influence of geological factors such as the presence of faults favor migration and degassing of the mantles studied.

scholarly journals Characterization of Coal Quality Based On Ash Content From M2 Coal-Seam Group, Muara Enim Formation, South Sumatra Basin

2017 ◽  
Vol 2 (3) ◽  
pp. 203
Author(s):  
Frillia Putri Nasution ◽  
Stevanus Nalendra
Keyword(s):  
Coal Seam ◽  
Research Area ◽  
Ash Content ◽  
Depositional Environments ◽  
Higher Plant ◽  
Delta Plain ◽  
Quality Aspects ◽  
Burning Coal ◽  
Coal Residue ◽  
Coal Seam Thickness

Muara Enim Formation is well known as coal-bearing formation in South Sumatra Basin. As coal-bearing formation, this formation was subjects of many integrated study. Muara Enim Formation can be divided into four coal-seam group, M1, M2, M3, and M4. The M2 group comprising of Petai (C), Suban (B), Lower Mangus (A2), and Upper Mangus (A1). Depositional environments of Group M2 is transitional lower delta plain with sub-depositional are crevasse splay and distributary channel. The differentiation of both sub-depositional environments can be caused the quality of coal deposit. One of quality aspects is ash content. This research conducted hopefully can give better understanding of relationship between depositional environments to ash content. Group M2 on research area were found only Seam C, Seam B, and Seam A2, that has distribution from north to central so long as 1400 m. Coal-seam thickness C ranged between 3.25-9.25 m, Seam B range 7.54-13.43 m, and Seam C range 1.53-8.37 m, where all of coal-seams thickening on the central part and thinning-splitting to northern part and southern part. The ash content is formed from burning coal residue material. Ash contents on coal seam caused by organic and inorganic compound which resulted from mixing modified material on surrounded when transportation, sedimentation, and coalification process. There are 27 sample, consists of 9 sample from Seam C, 8 sample from Seam B, and 10 sample from Seam A2. Space grid of sampling is 100-150 m. Ash content influenced by many factors, but in research area, main factor is existence of inorganic parting. Average ash content of Seam C is 6,04%, Seam B is 5,05%, and Seam A2 is 3,8%. Low ash content influenced by settle environment with minor detrital material. High ash content caused by oxidation and erosional process when coalification process. Ash content on coal in research area originated from detritus material carried by channel system into brackish area or originated from higher plant in brackish area. The high ash content also can be caused by after the coal deposited. It had originated from overburden horizon which infill in cleat of coal seam.

scholarly journals Influence of deep magma-induced thermal effects on the regional gas outburst risk of coal seams

2021 ◽  
Author(s):  
Jianshe Linghu ◽  
Wei Zhao ◽  
Jianbin Zhou ◽  
Zhiming Yan ◽  
Kai Wang ◽  
...  
Keyword(s):  
Coal Seam ◽  
Thermal Effect ◽  
Vitrinite Reflectance ◽  
Thermal Strain ◽  
Mining Area ◽  
Ground Temperature ◽  
Coal Seams ◽  
Mechanical Environment ◽  
Coal Resources ◽  
Gas Outburst

AbstractThe thermal effect caused by deep magma intrusion can not only accelerate the metamorphism of coal body, but also bring additional thermal field that changes the mechanical environment of coal seams, thereby affecting the permeability of coal seams. Different from shallow coal resources, deep coal resources are in a mechanical environment characterized by limited stress and strain. Thus, the thermal effect has a more significant influence on the distribution and permeability characteristics of deep coal seams. In this study, the evolution history of highly metamorphic coal seams in Yangquan mining area was analyzed, and the main effect of magmatic activity on coal seams was obtained. Based on the determined vitrinite reflectance data of typical mines in Yangquan mining area, the maximum paleotemperature was calculated by adopting the Barker’s method. Furthermore, the paleotemperature distribution in Yangquan mining area was summarized, and its relationship with the metamorphic degree was acquired. Then, a new permeability model considering the thermal strain was proposed to analyze the permeability evolution in deep coal seams at different ground temperatures. Finally, through a combination of the results of gas pressure and outburst number in Sijiazhuang Mine, Yangquan No. 5 Mine and Xinjing Mine, the influence of ground temperature on the gas outburst risk in Yangquan mining area was explored. The following conclusions were drawn: The maximum paleotemperature in Yangquan area can be 303 °C. In addition, the paleotemperature in the south is higher than that in the north of Yangquan mining area. The various temperatures at different depths bring about different degrees of thermal stress to different coal seams, leading to different strains. Under the fixed displacement boundary conditions in the deep, the coal seam folds and bends to varying degrees. Moreover, the difference in the ground temperature raises the a value of coal seams and lowers the permeability, which promotes the formation of gas-rich zones and increases the risk of coal seam outburst. The research results can help mines to make proper gas disaster prevention plan for different zones.

scholarly journals Impact of Sulphur Content on Coal Quality at Delta Plain Depositional Environment: Case study in Geramat District, Lahat Regency, South Sumatra

2017 ◽  
Vol 2 (3) ◽  
pp. 183
Author(s):  
Siska Linda Sari ◽  
Mutia Armilia Rahmawati ◽  
Alan Triyoga ◽  
Idar Wati
Keyword(s):  
Depositional Environment ◽  
Sedimentary Environment ◽  
Calorific Value ◽  
Research Area ◽  
Ash Content ◽  
Sulphur Content ◽  
Mineral Matter ◽  
Geological Condition ◽  
Delta Plain ◽  
Total Sulphur

The research was conducted in Geramat District of Lahat Regency, South Sumatra. An evaluation of the geological condition of the research area shown that the coal deposits were found in Muara Enim Formation as a coal-bearing formation. The method used was literature study, field observation and the laboratory work includes proximate and petrography analysis. The aim of this research is to determine the environmental condition of coal based on the change of total sulphur content and to know the relation between ash content to calorific value.  As the result of proximate analysis conducted on five samples of coal, the research area obtained total sulphur (0,21-1,54% adb), ash content (3,16 - 71,11% adb) and gross calorific value (953 - 5676 cal/g. adb). Based on the result of maceral analysis showed the maceral percentage of coal in research area composed by vitrinite (77,8-87,4 %), liptinite (0,6 %), inertinite (8,0 – 17,6 %) and mineral matter concentration in the form of pyrite (1,6-4,6 %). The average reflectance value of vitrinite (Rv) of coal in the research area (0.54%). the results analysis shows that the coal in Muara Enim Formation on the research area is in the transitional lower delta plain depositional environment phase. Any changes in the sedimentary environment affected by sea water will be followed by changes in total sulphur and the higher ash content, on the contrary, the lower calorific value of the coal.

GEOLOGICAL CONTROLS ON EXPLOITABLE COAL SEAM GAS DISTRIBUTION IN QUEENSLAND

2006 ◽  
Vol 46 (1) ◽  
pp. 343 ◽  
Author(s):  
J. J. Draper ◽  
C.J. Boreham
Keyword(s):  
Coal Seam ◽  
Vitrinite Reflectance ◽  
Gas Production ◽  
Gas Content ◽  
Burial History ◽  
Coal Seam Gas ◽  
Gas Generation ◽  
Delta Plain ◽  
Wide Range ◽  
Gas Fields

Methane is present in all coals, but a number of geological factors influence the potential economic concentration of gas. The key factors are (1) depositional environment, (2) tectonic and structural setting, (3) rank and gas generation, (4) gas content, (5) permeability, and (6) hydrogeology. Commercial coal seam gas production in Queensland has been entirely from the Permian coals of the Bowen Basin, but the Jurassic coals of the Surat and Clarence-Moreton basins are poised to deliver commercial gas volumes.Depositional environments range from fluvial to delta plain to paralic and marginal marine—coals in the Bowen Basin are laterally more continuous than those in the Surat and Clarence-Moreton basins. The tectonic and structural settings are important as they control the coal characteristics both in terms of deposition and burial history. The important coal seam gas seams were deposited in a foreland setting in the Bowen Basin and an intracratonic setting in the Surat and Clarence-Moreton basins. Both of these settings resulted in widespread coal deposition. The complex burial history of the Bowen Basin has resulted in a wide range of coal ranks and properties. Rank in the Bowen Basin coal seam gas fields varies from vitrinite reflectance of 0.55% to >1.1% Rv and from Rv 0.35-0.6% in the Surat and Clarence-Moreton basins in Queensland. High vitrinite coals provide optimal gas generation and cleat formation. The commercial gas fields and the prospective ones contain coals with >60% vitrinite.Gas generation in the Queensland basins is complex with isotopic studies indicating that biogenic gas, thermogenic gas and mixed gases are present. Biogenic processes occur at depths of up to a kilometre. Gas content is important, but lower gas contents can be economic if deliverability is good. Free gas is also present. Drilling and production techniques play an important role in making lower gas content coals viable. Since the Bowen and Surat basins are in a compressive regime, permeability becomes a defining parameter. Areas where the compression is offset by tensional forces provide the best chances for commercial coal seam gas production. Tensional setting such as anticline or structural hinges are important plays. Hydrodynamics control the production rate though water quality varies between the fields.

Petrology, palynology, coal facies, and depositional environments of an Upper Carboniferous coal seam, Minto Coalfield, New Brunswick, Canada

2000 ◽  
Vol 37 (9) ◽  
pp. 1209-1228 ◽  
Author(s):  
W Kalkreuth ◽  
D Marchioni ◽  
J Utting
Keyword(s):  
Coal Seam ◽  
Western Europe ◽  
Vegetation Index ◽  
Vegetation Indices ◽  
Depositional Environments ◽  
Mineral Matter ◽  
Petrographic Composition ◽  
Upper Carboniferous ◽  
Delta Plain ◽  
Coal Petrology

Coal petrology and palynology of the Minto coal seam enable depositional environments of the precursor mire to be established in terms of facies-critical maceral ratios, maceral assemblages, and spore and pollen assemblages. The overall petrographic composition indicates a vitrinite-rich coal (mean 67%), followed by inertinite (mean 27%) and liptinite (mean 7%). Pyrite is common to abundant (maximum 15%). Lithotype logs demonstrate a dominance of dull lithotypes (dull and banded dull). Petrographic composition at the lithotype and seam subsection level is highly variable. Vitrinite maceral assemblages are enriched in brighter lithotypes (banded bright and bright), whereas liptinite and inertinite maceral assemblages are enriched in dull and banded dull lithotypes. The duller lithotypes are enriched by mineral matter. Based on spores, the seam is assigned to the Vestispora Zone of Atlantic Canada, with the basal Torispora securis-Torispora laevigata (SL) Zone of western Europe and the lower Torispora securis-Vestispora fenestrata (SF) of the Illinois Basin. This indicates an early Bolsovian (Westphalian C) age. Based on the Tissue Preservation Index - Gelification Index facies concept, the seam was deposited in an upper delta plain. At the seam subsection level, facies-critical maceral ratios (Groundwater Influence Index, Vegetation Index) and maceral assemblages suggest both limnic (open moor) conditions and somewhat drier conditions. Relative low Vegetation Indices suggest mainly herbaceous source material, which is partly supported by the rare to common occurrence of small lycopsid spores and arboreous lycopods. The abundant sphenopsids, including Calamites, and rare gymnosperms may have grown outside the mire.

scholarly journals Comparison of the results of the seismic profiling and WAS-96/RMS seismoacoustic active method in an assessment of the impact of the overlying coal seam edge

2018 ◽  
Vol 66 ◽  
pp. 01011 ◽  
Author(s):  
Sławomir Olechowski ◽  
Krzysztof Krawiec ◽  
Jakub Kokowski ◽  
Zbigniew Szreder ◽  
Paulina Harba ◽  
...  
Keyword(s):  
Coal Seam ◽  
Research Area ◽  
Hard Coal ◽  
Coal Seams ◽  
Seismic Profiling ◽  
Complementary Method ◽  
Upper Silesian Coal Basin ◽  
Relative Stress ◽  
Comparison Of The Results ◽  
The Impact

In the study, a comparison between the results of seismic profiling and the active seismoacoustic method WAS-96/RMS has been presented. The methods were used to assess the impact of an overlying coal seam edge on the relative stress state of the test heading in the chosen hard coal mine in the Upper Silesian Coal Basin, Poland. The work presents the methodologies of measurement, processing and interpretation of both methods. In the research area there were two edges of the adjacent seams at vertical distances of 70 and 100 m. The obtained results allowed for the development of conclusions regarding the effectiveness of both methods. It was stated, that the seismic profiling method, as well as the WAS-96/RMS method allowed for the identification of anomalies in the area of impact of the overlying coal seams. Based on previous experience, a comparison of the advantages and limitations of the seismic profiling and the WAS- 96/RMS method has also been presented. As a result, it was found that seismic profiling should be the basic method for assessing the impact of the edges and remnants of exploited seams, whereas the WAS-96/RMS method may be used as a complementary method if a confirmation of the rockbursts threat is required.

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