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K-Ar dating of illite in fault gouges is a useful tool for constraining the timing of brittle fault movement; however, this can be problematic in fault gouges hosted in clay-rich rocks due to the influence of host-rock material. Therefore, this study employs a multianalytical geochemical approach to unravel the influence of host-rock mineralogy, as well as fault zone development, on ages from fault-gouge samples in a shale detachment zone. K-Ar dating of the ≥2 µm fraction of 6 samples from the Sap Bon Formation detachment zone and associated fault zones in the Khao Khwang fold-thrust belt of central Thailand yielded an age range of 262 ± 5.4 to 208 ± 4.6 Ma. Carbon and oxygen stable isotope analysis along with X-ray diffraction mineralogy indicate that the samples with the youngest K-Ar ages are characterized by higher grade clay mineralogy, and hotter, orogenic fluid temperatures. Using these proxies and comparison to existing geochronology of the study area, we correlated K-Ar illite ages to one of three stages of fault zone evolution: detrital, diagenetic (burial), and authigenic (fault movement). The youngest K-Ar dates in the Sap Bon Formation are contemporaneous with recently published zircon province data indicating that faulting and detachment zone formation in the Sap Bon Formation were occurring by the mid-Late Triassic, with deformation continuing as late as the Rhaetian.

The Rb-Sr dating technique is among the most widely used geochronological tool available in earth and planetary sciences. The method is based on the radioactive decay of 87Rb to 87Sr via a negative beta decay (the emission of an electron), with a half-life of 49.61 ± 0.16 Ga1. Traditionally rubidium-strontium dating has required the separation and acid digestion of mineral phases and/or bulk rocks, thus preventing high-resolution and micro-scale geochronology applications. Here we present results of the novel in-situ (laser-based) rubidium-strontium dating of selected mineral phases (i.e., glauconite and K-feldspar) in glauconite-rich strata of the Arumbera Sandstone from the northeast part of the Amadeus Basin in central Australia.

Circulating Fluid Bed technology has made a rapid and successful entry into power and steam generation marketplace in many countries. As one of the first CFB based power plants in Vietnam the 2 × 55 MWe Cao Ngan project will follow this trend towards clean coal technology. The Cao Ngan CFB boiler is designed to burn a blend of low-volatile, high-sulphur coals from two local mines complying with strict environmental regulations, 500 mg/Nm3 for SO2 and 300 mg/NM3 for NOx. Combustion tests were carried out at the University of Bochum, Institute of Energy Plant Technology, Germany, in a pilot-CFB combustor (100 kWth) in order to check the combustion behaviour and the emission characteristics. In these tests a blend of the two different coals was burned at different temperature levels (830 °C, 860 °C, 890 °C) and at each temperature level the desulphurisation efficiency was tested with two different kind of limestone and different Ca/S-ratios: Furthermore the experimental analysis comprised the determination of the conventional emissions (NOx, CO), ignition characteristics for start-up and part load behaviour. During all tests samples of bed and filter ash were taken for further analysis, e.g. burnout, particle size distribution etc.. Earlier comparable combustions tests carried out in the pilot-CFB combustor and large scale CFB boilers has proven, that the results are transferable to large scale commercial plants: This is valid especially for the major emissions e.g. SO2 and NOx. The current paper will explain the design principles and the basic lay-out of the Cao Ngan CFB boiler. In addition, details of the results of combustion tests carried out in a pilot- CFBC at the University of Bochum, Institute of Energy Plant Technology, Germany, will be presented.

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