Located at the crossroads between Africa and Eurasia, Arabia occupies a pivotal position for human migration and dispersal during the Late Pleistocene. Deducing the timing of humid and arid phases is critical to understanding when the Rub' al-Khali desert acted as a barrier to human movement and settlement. Recent geological mapping in the northern part of the Rub' al-Khali has enabled the Quaternary history of the region to be put into a regional stratigraphical framework. In addition to the active dunes, two significant palaeodune sequences have been identified. Dating of key sections has enabled a chronology of dune accretion and stabilisation to be determined. In addition, previously published optically stimulated luminescence (OSL) dates have been put in their proper stratigraphical context, from which a record of Late Pleistocene dune activity can be constructed. The results indicate the record of dune activity in the northern Rub' al-Khali is preservation limited and is synchronous with humid events driven by the incursion of the Indian Ocean monsoon.

A new lithostratigraphical framework for Singapore is proposed, based on the analysis of c. 20,000 m of core recovered from 121 c. 205 m deep boreholes and augmented with 218 field localities from across Singapore. The new framework describes a succession dating from the Carboniferous to the Quaternary. New U-Pb detrital zircon dates and fossil analysis were used to constrain the ages of key sedimentary units. The oldest known sedimentary rocks in Singapore are found to be the deformed Carboniferous (Mississippian) Sajahat Formation. These are succeeded by the newly erected, Middle and Upper Triassic, marine to continental Jurong Group and Sentosa Group successions that accumulated in the southern part of the Semantan Basin. The Jurong Group comprises four formations: the Tuas Formation, the Pulau Ayer Chawan Formation, the Pandan Formation and the Boon Lay Formation. The Sentosa Group contains two formations: the Tanjong Rimau Formation and the Fort Siloso Formation. In Singapore, the depositional record during this time is related to late Permian to Triassic arc magmatism in the southern part of the forearc basin to the Sukhothai Arc. The Jurong and Sentosa groups were deformed and weakly metamorphosed during the final stages of the Late Triassic to Early Jurassic orogenic event, deformation that led to the formation of the syn-orogenic conglomerates of the Buona Vista Formation. Following this, two distinct Lower Cretaceous sedimentary successions overstepped the Jurong and Sentosa group strata, including the Kusu Formation and the Bukit Batok Formation, both deposited in the southern part of the Tembeling Basin. A series of Neogene to Quaternary formations overly the Mesozoic and Palaeozoic stratigraphy, including the Fort Canning Formation, Bedok Formation and the Kallang Group.

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The Rub' al-Khali dune field in southern Arabia is the largest sand sea in the World. Deciphering the palaeoenvironmental history of the Rub' al-Khali is critical to understanding its role as a barrier to human migration, dispersal and settlement. To determine sediment provenance and transport pathways, we combined geological mapping with traditional heavy mineral optical point-counting methods, heavy mineral geochemical fingerprinting, and detrital zircon U-Pb geochronology of Miocene and Quaternary sediments in the United Arab Emirates (UAE).

The need to better understand how we source and consume the raw materials required for decarbonisation is driving a growing demand for data on mineral resources. A key application of these data is to understand resource potential, by evaluating known 'geological stocks' of raw materials based on estimates of mineral resources and reserves. However, the available resource data are often incomplete, totally lacking or compiled in different ways (i.e. industry reported data, which has significantly different user requirements to that of national level policy makers), making comparisons and aggregation near impossible.This study demonstrates the use of the United Nations Framework Classification (UNFC) to harmonise resource data for the UK. It highlights the benefits of this approach for improving the understanding of resource issues. Simple decision-making tools have been created, and are used to assist with classifying existing resource data using the three axes of UNFC, degree of confidence, technical feasibility and environmental socio-economic viability. These are designed to be applicable to a wide range of heterogenous datasets managed by national data providers. Their application to the UK, which has no system or national standard for collecting resource data, has served to highlight various issues relating to future mineral supply. These include variable data for deposits that may include multiple commodities such as co-and by-products, lack of data for minerals required for newly developing technologies and the variations in approaches for different commodity types.The compilation of standardised datasets can benefit national resource management, providing a 'snapshot' of the state of the UK minerals industry. For example, the results of this study facilitates inter-regional and international comparison and aggregations. In addition the consideration of the unique combination of geological, social and environmental factors by UNFC well as highlights where interventions may be needed if new projects to contribute to the green transition are to be developed. The use of the UNFC to classify mineral resource data, in a consistent way, by using the decision tools presented here, supports the creation and adoption of evidencebased raw material strategies. However, it is important to understand the limitations related to data gaps, consistency of approach and harmonisation of datasets from diverse sources.

Carbon capture and storage by mineralisation (CCSM) is a method proposed for capturing CO 2 by reacting it with magnesium in ultramafic rocks to form carbonate minerals and silica. Large quantities of magnesium silicate rocks are required for this process and to demonstrate the feasibility, and adequately plan for the development and supply of mineral resources, their locations and quantities must be known. This study attempts to globally define the spatial extent and quantity of resources that could be used for the CCSM processes and to asses, if based on resources, this could be a viable, widely applicable CO 2 sequestration process. It has been estimated that around 90 teratonnes of material is available. This is sufficient to capture global CO 2 emissions for over 700 years at current levels of output and highlights the enormous resource. Even if only a small part is utilised, it could make a significant impact on CO 2 reduction. The majority of the resource is contained within ophiolitic rocks. The study further attempts to split CCSM resources into altered (serpentine-rich rocks) and unaltered (olivine-rich rocks) due to the different processing requirements for these rock types. CCSM is likely to be of most use in areas with no access to underground geological CO 2 storage or for small operations where underground storage is not practical. This study demonstrates that substantial resources are available and their supply is unlikely to be a constraint.

Singapore bedrock geology is dominated by late Permian to Triassic arc magmatism and a genetically related, essentially Middle to Upper Triassic, marine to fluvial volcano-sedimentary inner forearc succession. These Mesozoic strata are deformed into a pattern of NE-translated ductile-brittle deformation structures during the latest Triassic to earliest Jurassic collision and amalgamation of the Sibumasu continental block with the southern part of the Sukhothai Arc. The subduction-related magmatic complex represented in Singapore by the granitic to gabbroic plutons of the Bukit Timah Centre likely acted as a backstop to thrusting at this time. Collisional tectonics drove progressive shortening and steepened earlier-formed inclined asymmetrical folds, culminating in the regional-scale development of a non-coaxial, NE-vergent and NE-facing, fold and thrust system. In Singapore, the Murai Thrust and Pasir Laba Thrust are identified as major elements of this system; both are associated with SW-dipping thrust-imbricate duplex slices. Two distinct early Cretaceous (Berriasian and Barremian) sedimentary successions overstep these collisional tectonic structures. An array of mostly NE-SW and ENE-WSW trending faults and fractures acts as important control on bedrock unit distribution across Singapore and are most likely generated by Cenomanian dextral shear stress. That stress locally reactivated faults initiated during orogeny, or even earlier. Knowledge of the geotechnical impact of these structural features is critical to both future development and ongoing management of the subsurface in Singapore.

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