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The Belaga Formation is a deep marine turbidite interpreted in relation to a submarine fan and therefore a prospect worth evaluating. The scope of this paper will focus on the shales from the thick sedimentary sequence of the Belaga Formation (Upper Cretaceous to Eocene) consisting of five (5) members in Central Sarawak, Malaysia, of which attention is given to the depositional environment and clay minerals as factors to consider as predictive tools for organic matter richness and gas storage capacity using the spectral gamma ray method using Thorium (Th), Potassium (K) and Uranium (U) as indices for inferences. A mineralogical chart of Th/K (ppm/%) indicates that the dominating clay minerals of the shales are mixed-layer types. The Th/U as a redox indicator is used to assert that the shales are of anoxic conditions of deep-marine environments. Despite the relatively high insoluble Th values (9.93-20.13) ppm, the presence of U in substantial amounts, which only occurs in reducing conditions where it is preserved as a lower insoluble valence (U4+) explains for the low Th/U values ranging between (1.86-4.57) ppm/ppm of the fifty-eight analyzed shale samples. The overall Th/U value of the evaluated shales remain less than 7, where Th/U < 7 is suggestive of marine sediments, grey and green shales, whereas Th/U < 2 is indicative of marine black shales of reducing conditions. The 30Ma interval of sediment deposition of the Belaga Formation Eocene recorded varied climatic fluctuations influential to clay minerals contained in the shales and ascribe the paleoweathering state of the shales, which from the standard imitative ternary plot of normalized K-U-Th of shales from Northern America address the shales of the Belaga Formation as of deep weathering residuum. [ABSTRACT FROM AUTHOR]

Summary: There is increasing concern about the availability of water supplies in developing countries to provide clean drinking water and sanitation as well as providing for irrigation for food security. This has led to hydrologically led investigation to establish the feasibility and storage capacity of potentially new dam sites. This task has become more difficult for hydrologists and others with the uncertainties created by climate change and the measurement of the hydrological, geographical and ecological footprint of new dams. The questions asked by hydrologists are increasingly likely to be required to be cast in terms of the four pillars of sustainability; environmental, economic, social and institutional. Similarly, regional planners have to be more cognisant of the social outcomes of dam development while understanding the wider hydrological context at a watershed and basin level. The paper defines the concept of sustainability assessment in the context of resettlement and analyses its implications for the Bakun Hydro-electric project in Sarawak, Malaysia. Specifically it attempts to address the question of what social sustainability would really mean in the context of communities affected by dam projects, and their catchments using hermeneutics, tradeoffs and offsets. The findings of this question were presented at a hydrological conference held in Santiago in October 2010, based on the outcome of specific questionnaire responses received from indigenous peoples affected by the Bakun Dam hydroelectric project. The paper also offers some insights pertaining to the social sustainability assessment aspects of dams and their catchments. [ABSTRACT FROM AUTHOR]

Despite the rich biodiversity of plants in the islands of southeast Asia, modern pollen reference collections are still sparse for this part of the world. With only limited availability of pollen data, the ability to answer questions, regarding climate change and environmental change, to aid archaeological investigations through the reconstruction of past vegetation, or even for modern investigations, is challenging. No palynological work had ever been carried out in the Kelabit Highlands of Sarawak, Malaysian Borneo, before this investigation. During 2007–2008, as part of the ‘Cultured Rainforest Project’, a number of cores were extracted for multi-proxy palaeoecological analysis, including pollen analysis. The cores produced a 50,000-year record of climate, environmental and later anthropogenic change. To aid fossil pollen identification, a modern pollen reference collection was also established. In August 2008, 253 modern plant species from a wide range of habitats were collected from in and around the villages of Bario and Pa’Dalih. Specimens were identified at the Department of Forestry Sarawak Herbarium (SAR), whilst pollen slides from all of the plant specimens were prepared at Queens University Belfast. This paper presents a detailed account of the pollen grains (176 species) collected from the Kelabit Highlands, and from SAR (25 species). [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the taphonomy of predominantly biogenic sediments and pollen in the key archaeological site in the West Mouth of the Great Cave of Niah, Sarawak. Strong spatial patterning of sediments and pollen were found, with a zonation related to distance into the cave. Near the cave mouth, sedimentation is silty and derived from waters running down the cliff outside the cave, with leaves from external vegetation. Pollen assemblages are similar to forest floor samples outside the cave, and thus are of airfall or wash origin. In the interior of the West Mouth, sedimentation is highly organic and composed largely of bird droppings. Pollen assemblages in the interior are strongly but regularly biased, with ‘over-representation’ of mangrove and riverine taxa resulting from the recruitment of pollen by bats and swiftlets foraging preferentially in these zones, over 7 and over 2 km from the cave, respectively. The significance of these findings for the understanding of humid tropical cave sequences and particularly for the current reassessment of Niah Cave is discussed. [Copyright &y& Elsevier]

This paper reviews quantitative biostratigraphic data from 101 petroleum exploration wells from the Malay, Sarawak and Sabah basins, and places the stratigraphy of each area into a precise chronostratigraphic framework comprising 41 transgressive-regressive depositional packages which are fully defined here. Each package is 'fingerprinted' by foraminiferal, nannofossil and palynological index fossils, and then tied to the global pattern of glacio-eustatic sea level and climate changes based on the global δ18O and δ13C datasets used to calibrate the geological timescale. The result is a tightly constrained chronostratigraphic framework that is applicable from deep to shallow water and is of high accuracy. It is concluded that there is a sedimentation 'pulsebeat' across Southeast Asia, independent of local and regional tectonics, driven by patterns of global climate change. For the Oligocene and Miocene, Antarctic glaciation is the key driver, whereas the Pliocene cycles are mainly driven by the expansion and contraction of Northern Hemisphere glaciers. The new chronostratigraphic framework allows unconformities across Malaysia to be better characterised, and the different classification schemes of seismic "Groups" in Malay and Penyu basins, "Cycles" in offshore Sarawak and "Stages" in offshore western Sabah to be correlated. Also, with a clear understanding of the effect of fluctuating sea levels on the stratigraphy of the region, it is easier to make firm judgments regarding the effect of tectonics. The study also characterises systems tracts from shelf to basin floor using biostatigraphic assemblages, which should help in ground-truthing the architecture of depositional sequences in the region based on seismic. The new framework is proposed as an alternative to the outdated TB scheme of Haq et al. (1988) , widely used to interpret depositional cycles across Sarawak and Sabah. Image 1 • 101 Malaysian exploration wells were studied for Sequence Biostratigraphy. • 41 depositional cycles have been defined from the mid-Oligocene to Pliocene. • Ages are 'fingerprinted' using age-restricted foraminifera, nannofossils and pollen. • Cycles were driven by Antarctic, followed by Arctic ice volume changes. • The study identifies major issues with the 'Haq' and other sea level curves. [ABSTRACT FROM AUTHOR]