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The present work is conducted on the Paleozoic (Ordovician) Khabour and the (Silurian) Akkas shales in the Akkas-1 well of western Iraq aiming to determine the implications of clay mineral transformation and organic mineral distribution and maturity for hydrocarbon generation using X-ray diffraction (XRD), scanning electron microscopy (SEM) in addition to organic matter concentrates. In the shale of the Khabour Formation, amorphous organic matter is common and includes various Tasmanite-type organic matter, vitrinite, inertinite and bituminite. The main clay minerals observed include; illite, chlorite, kaolinite, in addition to mixed-layer illite-smectite and rare smectite. In Silurian shale, a lot of organic matter is recorded in addition to abundant vitrinite, some grainy organic matter (Tasmanites) and pyrite with common illite, kaolinite in addition to chlorite and illite-smectite clay minerals. Conversion of smectite to mixed-layer illite-smectite (I-S) and increase in vitrinite reflectance are commonly observed below 2500 m depth in the studied formations and this coincides with oil and gas generation. These results could be used as an indication of higher maturity and hydrocarbon generation in the deeply buried shale of the Khabour and Akkas formations in western Iraq.

The Sydney Basin is a geological province of great historical, social and economic significance to Australia. It was the site of the first landing by James Cook in 1770 and the first European settlement in 1788, and has since become the geological host for Australia’s most populous urban area. Some of the earliest publications on Australian geology, by authors such as Dana (1849), Clarke (1861, 1867) and David (1890), dealt with aspects of Sydney Basin geology. The geological features of the basin were also critical factors in the infant colony’s development. Outcropping sandstones around the first settlement, for example, provided construction material for many of Sydney’s historic buildings, while the sandstone cliffs of the Blue Mountains formed a topographic barrier that had to be crossed before settlement could expand beyond the coastal fringe.

The Late Permian mass extinction was not only the most catastrophic known loss of biodiversity, but was followed by unusually prolonged recovery through the Early Triassic. Opinion has been divided on whether delayed recovery was a legacy of especially profound ecological disruption, or due to additional environmental perturbations. New records from the Sydney Basin in southeastern Australia now reveal five successive Late Permian and Early Triassic spikes of unusually high atmospheric CO2 and profound chemical weathering. These successive atmospheric CO2 greenhouse crises coincided with unusually warm and wet paleoclimates for a paleolatitude of 61°S. Successive transient greenhouse crises punctuated long-term, cool, dry, and low-CO2 conditions, and may account for the persistence of low diversity and small size in Early Triassic plants and animals.

Petrographic (optical, scanning, and backscattered electron microscopy), mineralogical (X-ray diffraction) compositional analysis of interbedded sandstones and shales from the Ordovician-age Khabour Formation of western Iraq were investigated in order to determine the diagenetic evolution of these units. The Khabour sandstones are generally quartzarenites with subordinate sublitharenites and subfeldsarenites which were deposited in a range of shelf environments (offshore shelf through tidal-storm regressive middle shelf to near-shore inner shelf). Several diagenetic events have affected the Khabour sandstones including compaction, cementation, replacement, dissolution and alteration. Early diagenetic events were closely related to the composition of depositional water (especially in terms of oxygen and sulphate content), Fe and organic content of the sediments, rate of sedimentation, and proximity to the shoreline. Shales interbedded with the sandstones contain evidence of authigenic illite, chlorite, kaolinite and mixed-layer illite-smectite. The later diagenetic events within the Khabour Formation were related to the burial history of the sandstone and shale succession as it was deposited on the slowly-subsiding shelf. Typical features include quartz overgrowths, the development of authigenic kaolinite, chlorite and illite, albitization, as well as Fe-dolomite and titanium and ferruginous cementation that resulted in decreased permeability by reducing pore-throat openings in the studied sandstones.

Coal was discovered in Australia in 1791 by William Bryant, a convict, near the mouth of the Hunter River at Newcastle, New South Wales (NSW). Later discoveries were made along the Brisbane River and ncar Ipswich in the 1820s. Mining commenced in Australia in 1799, also in NSW. The earliest scientific input to coal exploration was when Sir Joseph Banks, in 1799, introduced drilling equipment to Australia (Bryan, 1990a). Since then, production of coal has occurred in all states with the exception of the Northern Territory. In NSW, Queensland and Western Australia the mined coal is predominantly of bituminous rank, whereas in South Australia, Tasmania and Victoria the coal is sub-bituminous or brown in rank. NSW and Queensland have the largest resources of bituminous coal with the bulk of the production coming from NSW prior to the development of the extensive Bowen Basin coal deposits in Queensland. Queensland is now the largest producer of coal in Australia.The majority of Australia's brown coal reserves are located and mined in Victoria with most used for electricity generation.

Carbonate minerals commonly occur in coals of many ages and from a utilisation viewpoint can be deleterious. Several studies have been undertaken of the carbonates in the Permian coals of the Hunter Valley, Australia, but few studies use a multi-technique approach. For this study, a combined petrographic, geochemical and mineralogical approach was used to determine the distribution and residence of carbonate minerals in coal that had been intruded by a dyke. The dominant carbonate assemblages comprise primary siderite in inertinite-rich microlithotypes and secondary calcite(–ankerite–dolomite)–dawsonite in vitrinite-rich microlithotypes. The secondary carbonates were found in both the aureole of heated coal and also in an unheated mine-face sample. It is believed that the secondary carbonate minerals precipitated from magma-derived fluids percolating through the coal following the emplacement of the intrusions. The textures and distribution of the secondary carbonate minerals suggest that the temperature and pressure of the fluids may be just as important in developing fractures near dykes (particularly those that have multiple phases of geometries), cleat mineralogy and coal textures as direct heating from the intrusion. The partitioning of primary siderite with inertinite and secondary carbonates with vitrinite indicates that it can be reasonably expected that there would be a partitioning of minerals in various density fractions derived from float–sink tests and consequently a partitioning of elements with inertinite-rich fractions containing elevated Fe levels and vitrinite-rich fractions containing elevated Ca, Mg and Al. This partitioning has implications for the behaviour of the coal during washing and combustion, and the composition of combustion products.

The provision of water supply, its usage and discharge, are major concerns for all mines, often accounting for a significant portion of the daily running costs. To reduce these costs, mines will collect as much site runoff as possible, and recycle the water whenever economically feasible. The constant recycling of on-site waters can mean that, over time, the levels of salinity, acidity or alkalinity, or other contaminants may build up within the internal water management system to a point which may lead to problems with licensed discharge requirements. This project investigated the water quality at West Cliff Colliery, in order to develop an improved system for managing water resources with minimal environmental impact. While West Cliff Colliery is totally self sufficient and independent of any town water supply, issues have arisen with the quality of water being discharged into the receiving waterways, Brennans Creek and the upper Georges River. To alleviate these issues, a new water management system (WMS) has been established to try and maintain an adequate supply of clean recycled water and to prevent uncontrolled discharges to the environment outside West Cliff's Environment Protection Licence (EPL) requirements. This paper reports on the design of the new WMS, results of monitoring its effectiveness results, and implications for mine operations and environmental licence compliance.

This paper reports on a water quality monitoring program carried out for Wingecarribee Shire Council between March 2002 and July 2004 by University of Wollongong staff and students. Initially 40 sites were sampled on four occasions over three months in a pilot program leading to the selection of sites and parameters for a two year program of monthly monitoring. A range of chemical, physical and biological parameters was measured including nutrients and faecal coliform bacteria on samples collected over the 26 approximately monthly sampling trips. Chlorophyll a, phaeophyton and blue-green algae were also determined over a shorter period. The sampling period included the particularly hot and dry spell September 2002 - January 2003 and a return to less extreme conditions after February 2003. The range of nutrient and coliform data is reported with discussion of the effects of rainfall patterns on nutrients and on faecal coliform counts at the various sites. Small creek sites showed significant changes to nutrient regimes in the long dry spell, whereas the same effect was not apparent in larger river sites. Very wide ranges of faecal coliform counts were found, especially at small creek sites in farmland. Excepting extreme results, generally elevated coliform counts were found when rainfall occurred 0-3 days immediately prior to sampling. Generally lower counts were found in drier weather. The Shire has already implemented some measures to improve water quality in response to this program.

The adjacent Huon and Derwent estuaries in Tasmania have similar climatic and physical characteristics, and provide a good comparison between relatively uncontaminated and industrially polluted estuaries, respectively. Representative samples were collected from both estuaries and analysed for grainsize and trace‐element content (using X‐ray fluorescence and neutron activation analyses). The Huon estuary drains a predominantly forested and agricultural catchment and contains low (baseline) concentrations of trace elements, including lead, zinc and copper. In contrast, the Derwent estuary has a geologically similar yet larger catchment and it passes through an industrialised area in the midestuarine reach. A zinc refinery has, in the past, been a major source of trace‐element contamination. These contaminants are distributed downstream from the refinery by combined fluvial and tidal activity, while the latter also causes upstream movement of contaminants during non‐flood periods. Significant upstream contamination is limited by fluvial bottom flows remobilising contaminated fine sediment during flood periods. Maximum contamination occurs in the region around the refinery with values in the surface sediments ranging from 40 to 565 times baseline levels and from 2 to 55 times the Australian Interim Sediment Quality Guidelines high‐levels for aquatic sediments (maximum 22593 ppm Zn, 3866 ppm Pb and 1182 ppm Cu). In the lower Derwent estuary, contaminant distribution is inversely related to tidal‐flow velocities and is most prominent in the lower energy muddy substrates. Trace‐metal levels in the more recent surficial aquatic sediments are slightly lower than those recorded in a previous study from the area, possibly reflecting the stricter environmental controls now operating.

Provenance and sediment distribution have been investigated in the Minnamurra estuary and the adjacent shelf in NSW, Australia. Heavy mineral assemblages in the sand fractions (63-250 f.lm) of 110 surficial sediment samples were assessed using microscopic and microprobe analyses. In addition to the dominant opaque minerals, twelve translucent heavy mineral species were identified. The translucent assemblage is dominated by pyroxene, zircon, tourmaline and hornblende. Statistical cluster analysis of heavy mineral percentages in the surficial sediments revealed the existence of five mineralogical facies: the upper fluvial part of the estuary, the Minnamurra spit and elevated inner sand terrace, the estuary inlet and inner part of the inner-shelf, a combined group consisting of the outer part of the iriner-shelf and the midestuary (Rocklow Creek), and the mid-shelf facies. The main factors that control the distribution of the surficial sediments and their contained heavy minerals are transport and hydraulic sorting processes, together with minor coastal erosion. This can be seen clearly on the shelf area with denser heavy minerals concentrated in shallow water deposits whereas the lighter platy heavy minerals become more prominent in the deeper water lower energy areas. The mid-estuary facies is a mixed zone that has a similar heavy mineral assemblage to the outer part of the inner-shelf; possibly resulting from reworking of marine-influenced sand sheets in the Rocklow Creek catchment. The Minnamurra spit (aeolian dune) and elevated inner sand terrace facies is distinctive with its high concentration of total heavy minerals, resulting from winnowing by wind and storm wave influences. The heavy mineral assemblage also identifies multiple sources. The occurrence of heavy minerals from non-local source rocks reflects reworking of quartz sand from the outer-shelf to the inner-shelf and coastal environments during the post-glacial marine transgression. These minerals were o

Zircon-bearing rhyolitic and dacitic airfall tuffs in the Late Permian Sydney Basin coal measures provide ideal chronostratigraphic markers due to their widespread occurrence and rapid emplacement. SHRIMP U-Pb zircon dates for several stratigraphically-controlled airfall tuffs are consistent with their relative ages and biostratigraphic data, and indicate that the Illawarra Coal Measures accumulated in less than ~ 12 million years. Isotopic ages of the A waba Tuff and the Burragorang Claystone Member are indistinguishable within analytical uncertainty and support the correlation of these units proposed previously on the basis of geochemical fingerprinti~g. Deposition of coal-bearing sequences in the southern Sydney Basin apparently commenced a few million years before deposition of similar sequences in the Bowen Basin but deposition ceased at the same time in both regions.

Oil shales are a diverse group of rocks that may become an important source of liquid fuel and chemical feedstocks. The bulk of the organic matter in oil shales is generally exinite derived from a variety of organisms ranging from terrestrial higher plants to freshwater and marine algae. In this study reflected light and fluorescence mode petrography provide data not readily available through chemical, transmitted light and palynological studies. The petrographic studies elucidate the mode of preservation and mineral-maceral relationships usually destroyed during mineralization and pyrolysis. Previous petrographic terminology for algal components is revised and two new terms, lamalginite and telaginite, are defined. Type of exinite is used to classify oil shales into three primary and six secondary groups. Telalginite derived from Reinschia and Pila, both related to the extant green alga Botryococcus braunii, is the major exinite in torbanite which is formed in shallow lakes associated with coal forming swamps. The reflectance of vitrinite in torbanite decreases as the alginite content increases. Lamosites are freshwater, laminated oil shales and are divided into Rundle type and Green River type. Australian Tertiary lamosites belong to the Rundle type and contain discrete lamalginite derived in part from the colonial green alga Pediastrum, the freshwater dinoflagellate Septodinium, and the acritarch Cleistosphaeridium. Botryococcus telalginite and huminite are minor constituents. Green River lamosite contains layered lamalginite with minor bitumen and huminite. Differences between the two forms of lamalginite in the Rundle and Green River type lamosites indicate that the environments of deposition were not the same for both types. Australian Tertiary lamosites were deposited in fresh to brackish water, probably nearshore lakes. Recognition of phytoplanktonic algae, but not benthonic or mat-forming algae, suggests that the bulk of the exinite in these lamosites was d