Time contained within coal seams is most commonly estimated using a volumetric approach that fails to take into account processes of carbon accumulation and loss during peat formation and coalification. A more appropriate approach for estimating the time contained within a coal seam is to use Holocene long-term carbon accumulation rates, accounting for carbon loss during coalification. Using this approach the thickness of coal corresponding to 10 kyr of carbon accumulation is calculated for coals of all ranks and latitudinal settings. To test the validity of this approach, latitudinal patterns of Holocene dust deposition are used in conjunction with estimated rates of carbon accumulation to calculate the concentration of titanium in coal. The result is a statistically significant correlation that is optimized when latitudinal variation in carbon accumulation rate is considered. Overall, the use of carbon produces far greater accountability of time within coal-bearing stratigraphic sequences and is not influenced by the presence of hiatal surfaces within the coal. Estimated coal seam duration increases considerably, often removing the need to infer substantial intra-seam hiatuses. On the basis of the results, a re-evaluation of coal and coal-bearing stratigraphic sequences is recommended.

The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.

No abstract

No abstract

Rapid population growth in South-East Asia has placed immense pressure upon lowland regions both to supply food and employment and space for residential, commercial and infrastructure development. This pressure has led to sites on tropical peatland previously considered unsuitable for development to be revisited. One such site, the KLIA2 terminal and runway, Kuala Lumpur International Airport which opened in May 2014 at a cost of 3.6 billion MYR has been beset by well documented subsidence problems. Coverage of the tropics by the Sentinel-1 satellite constellation presents an opportunity to monitor the ongoing subsidence at KLIA 2, identify potential knowledge gaps and help inform more sustainable infrastructure development in tropical peatland regions. Our results show that the ISBAS InSAR method produces reproducible ground deformation maps which can clearly identify the patterns of deformation across both urban infrastructure and adjacent rural plantations and tropical peat swamp. This is particularly well defined around the terminal building at KLIA-2 where different ground preparation and foundation design have resulted in stable terminal buildings and subsidence of surrounding pavement. Deformation is greatest in the runway area where alternate bands of uplift and subsidence presumably accompany the greatest loads associated with landing aircraft. In contrast, areas where peat replacement was the primary form of ground preparation, ground motion is stable, however this comes at high economic and environmental cost.