Academic literature on the topic 'Callide Coalfields'

A number of spore tetrads with variable ornamentation have been observed during the palynological study of Lower Panchet sediments (Early Triassic) of the Raniganj Coalfield. They are either cingulate (ornamented or smooth) or simple verrucose spores, and can be attributed to Lundbladispora, Densoisporites and Verrucosisporites. The abundance of tetrads in the assemblage may be assigned to the diminishing effect of callase due to change in the climate. This perhaps resulted into the non-dissolution of the callose-wall which holds the spores together in a tetrad.

AbstractA large number of naked, fossil spore tetrads assignable to the dispersed microspore genera Indotriradites, Microbaculispora and Microfoveolatispora are reported for the first time from an early Permian stratum (Lower Barakar Formation) of Singrauli Coalfield, Son-Mahanadi Basin, Central India. This is also the first record of tetrads from any Artinskian strata in the world. There is no evidence of any kind of sporangia or related plant parts in the present investigation that could ascertain the affinity of these tetrads; however, the presence of a trilete mark in the spores of the tetrads demonstrates their alliance at least with the pteridophyte group. The present study suggests possible factors affecting the sporogenesis process in the past, considering other available global records pertaining to fossil spore tetrads. The results of significant physiological and biochemical analyses performed on the anthers of modern plants related to reproductive biology, in order to understand the conditions and changes responsible for the formation of tetrads, are also considered. We analysed the globally occurring fossil tetrads and the palaeoclimates prevailing during their deposition. A correlation between extreme climatic conditions, specific pH values inside microsporangium and the formation of tetrad is envisaged. It is deduced that extreme climatic conditions (extreme cold/extreme hot) might have triggered some sort of malfunctioning in the sporogenesis process that altered the specific pH values inside the microsporangium. Any restraint of the activity of the callase enzyme, responsible for dissolution of callose walls laid between the individual spores, may therefore have apprehended the dissociation of tetrads into individual spores.

The Late Triassic Callide Coal Measures are preserved in a small (22.5 by 8 km), shallow, partly fault-bounded basin remnant (the Callide Basin) near the town of Biloela in east-central Queensland. The largely undeformed basin-fill unconformably overlies a variety of Palaeozoic rocks which were strongly folded and thrusted during the Hunter-Bowen Orogeny. The Callide seam Member is the thickest and most economic of four seam members within the coal measure sequence. The coal is characteristically sub-bituminous and is dull, sub-hydrous, and sold unwashed. Its most striking feature is a high mineral matter content and significant concentrations of iron minerals exist, comprising up to 8% of the coal, or 50% of the coal ash. Thin layers of elastic rocks (up to 0.4m in thickness) which are interbedded with the coal or are immediately underlying coal seams, can contain up to 56% iron minerals (76% in ash). The spatial variability of the iron.minerals is high, which impacts upon coal quality parameters during coal utilisation. Of particular concern is the variable and unpredicted performance of the coal during combustion. Although high iron in ash generally relates to deleterious slagging behaviour during combustion, other factors also impact upon performance. Previous studies by several workers have focussed on the coal product and end-use problems with less than successful results. This study differs by seeking to determine geological and geochemical controls on the distribution of high iron zones in Callide coals and the effect of mineral composition on coal combustion. The study is interdisciplinary, and investigates iron distribution and mineralogy at progressively smaller scales, starting at the basin-wide level and progressing through to coal deposit and then to individual seam distributions. At the basin-wide level, modelling of total iron within the Callide seam Member has shown that iron concentrations are higher along the western margin of the basin, where the entire sequence is thicker. Furthermore, iron mineralisation also seems to be highest on either flank of the synclinal axis of the basin, which trends north-west, parallel to the regional structural grain. At the deposit level, iron distributions are not so easily characterised, being manifest as a complex mosaic of narrow, elongated zones containing between 20-50% iron in coal ash surrounded by more subdued zones of moderate iron mineral concentrations, whose location varies for each seam. Some of the iron mineralisation is clearly discordant to bedding attitudes. Vertical variability in iron content within a profile also is not consistent across the basin, but iron minerals habitate generally at the base of seams, in soft, moist, "sooty" fusainous layers, in intra-seam claystone partings or "hardpan", and near structural discontinuities. The application of detailed coal characterisation techniques has determined that upwards of 90% of the iron minerals in the Callide seam Memter are siderite, goethite and pyrite. The remainder are primary iron oxides, such as haematite, and trace amounts of hydrated iron sulphates. Some of the iron oxides are weakly magnetic. There are at least two phases of siderite present, one as spherules or nodules that apparently formed at low temperatures and shallow depths, early in coal diagenesis, from meteoric waters in a formative peat swamp. Both siderites are very pure, with negligible substitution of Mn, Mg and Ca cations into the lattice. The other occurs as cleat and/or vein infillings formed after coalification. Possibly a third phase, with similar morphology, has formed from recent oxidation. These latter two siderites, except at Boundary Hill Mine, form only a small percentage of the total siderite present. The vertical variability measured generally corresponds to the scale of bounding surfaces in dulling upward coal cycles. These surfaces, which may relate to flooding events, could have provided an environment for primary siderite formation, or provided discontinuities, and/or porous conduits for secondary fluid migration and iron mineralisation. Nonetheless, the fundamental control on the high and variable iron distribution along the western margin of the basin appears to be structural (ie. related to jointing, faulting and igneous intrusions). Stable carbon and oxygen isotope analyses combined with petrographic evidence suggests that the siderite and its host peat show characteristics consistent with repeated in-situ oxidation. Such indicators include lack of calcite, a subdued pyrite presence, high inertinite,(and particularly micrinite) contents, and weathering of the siderite to goethite. Sufficient similarities exist to characterise the Callide seam Member as a very low-grade fossil bog iron ore deposit. In the second half of this study, the influence that high iron mineral concentrations have upon the physical, geochemical, and geophysical properties of the coal are examined. Apart from affecting the visual appearance of the coal, the high and variable mineral matter contents affect interpretation of certain downhole geophysical logs. Furthermore, the calculation of the apparent relative density, volatile, and mineral matter of the coal is affected, and subsequently impacts upon the correct classification of the coal. High concentrations of iron minerals in the coal increases the coals' carbon char reactivity, but impinges upon combustion behaviour. It is within this framework that the interaction of these iron minerals with other minerals in the coal was further investigated to explain the variable performance of the coal upon combustion. Identification of coal attributes causing adverse boiler slagging, ahead of mining, was most successful when the author modelled ratios of the most significant minerals present: kaolinite, siderite, and quartz.

Traditional geophysical techniques, such as electrical, magnetic, seismic and gamma spectroscopic methods, have been deployed across the Callide Basin, Eastern Central Queensland, intent on delineating basin -wide structures. Further, innovative surface and borehole geophysical techniques have been applied for coal mine -scale exploration and production with the intention of reducing global geological ambiguity and optimising exploration resources at Callide Coalfields.

A very low frequency electromagnetic surface impedance mapping method, the SIROLOG downhole technique, acoustic scanning, electromagnetic tomography and

full wave -form sonic borehole logging have been trialed for geological hazard and mine design applications at Callide Coalfields as the precursor to their wider

application and acceptance in the Australian coal industry.

In this thesis, the theoretical basis for these techniques is provided. However, more importantly, the case studies presented demonstrate the role that these geophysical

techniques have played in identifying geological structures critical to mining.

Reverse faults that daylight in highwalls and intrusions constitute geological hazards that affect safety, costs and scheduling in mining operations. Identification of the limit

of oxidation of coal seams (coal subcrop) is critical in mine design. During the course of this thesis, the application of geophysical techniques resulted in:

a) a major structure (the "Trap Gully Monocline") being redefined from its original

interpretation as a normal fault to a monocline that is stress -relieved by minor scale thrust faulting;

b) two previously unidentified intrusions (the Kilburnie "Homestead" plug and The Hut "Crater" plug) that impinge on mining have been discovered;

c) the delineation of two coal subcrop lines has resulted in the discovery of an additional 1.5 million tonnes of coal reserve at Boundary Hill mine and the successful redesign of mining strips at The Hut Central Valley and Eastern

Hillside brownfield sites; and

d) the first ever attempt to petrophysically characterise the lithotypes within the Callide Basin.

This concluding chapter talks about how strong continuities endure between the movement against mountaintop removal as it existed in 2003 and the various forms that have emerged through 2010. Particular attention is given to several important developments that warrant specific mention. Efforts challenging the coal industry and regulatory agencies continued to succeed in federal district courts. Working with grassroots organizations and national environmental law organizations like Earth Justice, Joe Lovett, and others have successfully challenged several specific pieces of mine regulation and enforcement, including the so-called Nationwide-21 permit procedure. Seasoned coalfield residents provided powerful firsthand testimony that yielded credibility to the MTR movement. Meanwhile, youthful enthusiasm and civil disobedience often drew public attention and new interest to the cause, particularly among young people and college students.

The United Mine Workers of America (UMW) had roughly 13,000 members when it called for a nationwide suspension in bituminous coal production in April 1894, but over 150,000 primarily non-union miners quit work in support of the UMW-orchestrated strike for better pay. Despite their longstanding hostility to UMW leaders and organizing tactics, miners in southern coalfields like Missouri and Kentucky were among the thousands to join the strike but not the union. This essay considers why laborers would follow the orders of a union they refused to join by considering the social and economic factors that shaped miners’ concepts of unionism. Ultimately, non-union participation in the 1894 coal strike demonstrated that non-unionism did not necessarily denote a rejection of union sentiment. Rather, workers could maintain a culture of faithfulness to union ideals even if they did not maintain union membership.

Part 3, which includes chapters 5, 6, and 7, focuses on Letcher County, Kentucky, in order to examine the long contest over, and eventual defeat of, what would have been the newest prison in the coalfields, USP Letcher. Many of the justifications for construction hinged on the prison’s putative ability to sustain the county amidst historic lows of coal employment and production levels. Chapter 5 examines in detail how local civic and political elites–what one research participant has called the “Mountain Royalty”–attempted to position the county favorably to entice the prison. This occurred through shaping and policing local discourse as well as through mundane, although no less important, political and financial maneuvers designed to attract and retain the prison, in part to complete infrastructure projects and shore up revenue shortages. This chapter examines these granular efforts in order to better explain the importance of regional planning and development to the carceral state.