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We investigated the distribution of modern benthic foraminifera from Kelantan waters in the western part of the Sunda Shelf, South China Sea. Twenty-nine benthic foraminiferal species were identified from seven samples collected along a ∼250 km-long transect perpendicular to the Kelantan coastline. Calcareous hyaline species made up 57% of the overall assemblages collected in the study area, followed by calcareous porcelaneous (23%) and agglutinated (20%) species. Cluster analysis recognised two distinctive groups. Group A represented the shallow inner-shelf area (19–35 m water depth) with a coarse sand-dominated substrate where Amphistegina papillosa (13.37%) and Assilina ammonoides (11.04%) were highly abundant. Group A had lowest diversity with no agglutinated species. Group B, occurred at 40–60 m water depth, had higher foraminiferal diversity and was characterised by a very fine sand substrate. The foraminiferal assemblages here were dominated by calcareous hyaline species in group B followed by calcareous porcelaneous and agglutinated species. Group B was characterised by Assilina ammoinodes (11.04%), Heterolepa dutemplei (10.29%), and Discorbinella bertheloti (10.03%). The dominant agglutinated species in Group B were Textularia agglutinans (4.93%) and Cylindroclavulina bradyi (3.55%). Shallow-water species, such as Amphistegina spp., were absent from Group B. Our study shows that the distribution of benthic foraminiferal assemblages from the western Sunda shelf off Kelantan, is closely associated with changes in seafloor sediment, distance from the shore, and water depth.

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SUMMARYIraq has a long history of hydrocarbon exploration which included the regional gravity surveying of Iraq using land gravity and aeromagnetic methods. These exploration data sets have now been fully compiled into digital products which provide a wealth of new structural and sub surface information for the shallow parts of the basins (main seen by the gravity data) and deep basement structures (mainly seen by the aeromagnetic data). These responses result from a strongly magnetised basement and weakly magnetised sediments that vary from 4-5 km to in excess of 13 km in thickness in eastern Iraq. Since sediments increase in density with depth due to compaction, the gravity anomalies will be associated with tectonic movements (faulting and folding) that have laterally offset the sediment layers and densities.Detailed integrated geological and geophysical studies over the basement areas of the Arabian Plate show the basement has been affected by three main structural trends from oldest to youngest The Pan African Idsas Fault System (1000-780 Ma) Najd Fault System (680-620 Ma) Transversal Fault System (Latest Precambrian)The most recent structural deformation is the ongoing Alpine folding event in NE Iraq. This is due to the northerly movement of the Arabian Plate and collision with the Anatolian Plates first producing the E-W trending anticlines followed by the stress introduced against the Iranian Plate in a NE-SW direction resulting in NW trending anticlines of NE Iraq; some are overprinted over the Anatolian trend in N Iraq.The poster presentation will focus on the construction of both the gravity and aeromagnetic databases and show images how the gravity and magnetic data relate to the principle basement structural trends and Alpine deformation.