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Holocene sediments of the north Norfolk coast (NNC) between Weybourne and Hunstanton have been studied using geophysical, sedimentological, biofacial and dating techniques. New cores and refraction seismic data have defined the topography of the pre-Holocene surface and show that the NNC sediment prism is underlain by an east-west trending Quaternary trough, probably a palaeo-river-valley. The age of the Holocene fill has been dated using radiocarbon and luminescence dates, while sedimentation rates were constrained by, and compared with, modern rates using radionuclide data. The Holocene sediments are divided into a sandy-barrier lithofacies association (LFA), and a muddy-silty-peat back-barrier LFA. The oldest Holocene sediments are peats, formed on an undulating till surface. These peats were forming by 11-10 cal. ka bp and continued to form until at least 7 cal. ka bp in a number of places. As Holocene sea-level rose, marine mudflat and saltmarsh environments began to form between 7 and 6 cal. ka bp east of Holkham and around 6 cal. ka bp or younger west of Holkham. A marked erosion surface between the barrier and back-barrier LFA in the Holkham to Burnham Overy area is imperfectly dated at <3 cal. ka bp, but suggests the sediment prism has thinned by about 3 km over 6 to c. 3cal. ka bp. This surface probably records the westward progress of laterally migrating tidal channels that caused back-barrier sediment erosion, along with shoreface processes, as sea-level rose. Small-scale regressive and transgressive saltmarsh sequences occur at different elevations along strike but cannot be correlated, suggesting that the control on saltmarsh and mudflat development is autocyclic rather than allocyclic. Generally, transgressive and regressive events are related to disposition of coastal barriers and these are superimposed on a general facies evolution governed by regional sea-level change. Predictions about how this barrier coastline might respond to increased rates of regional sea-level change caused by global warming, or climatic events like increased storminess, require an understanding of how specific segments of the coastline have responded over millennial time-scales. This longer-term evolution provides the baseline information for decision making and management strategy. It is likely that sandy sediment supply is limited on the NNC and this implies that the barriers will continue to move landward, probably at increased rates relative to today, suggesting that parts of the NNC will become more vulnerable to erosion and flooding.

Three closely-spaced sites (Sites 717, 718, and 719) were drilled on the distal Bengal Fan in the central Indian Ocean at a water depth of 4735 m and to a maximum penetration of 962 mbsf. This paper presents a synthesis of results from both shipboard and shore-based studies, with particular emphasis on the lithofacies, their depositional processes, and sediment source. The sediment record at all three sites can be divided into five distinct lithologic units: Units I, III, and IV are mud-rich with relatively low accumulation rates (<70 m/m.y.), whereas Units II and V are silt-rich with high rates of sedimentation, in parts in excess of 350 m/m.y. The oldest sediments recovered are early Miocene in age, approximately 17 Ma. Seven sediment facies are recognized. Light-gray silt and mud turbidites (Facies 1 and 2) are the most dominant throughout, and were derived from rapid erosion of the Himalayas. Transport was to the Ganges delta/shelf region and then resedimentation occurred downslope, in some cases in very large powerful turbidity currents that traveled over 2500 km and deposited beds up to 2.5 m thick. Dark-gray, organic-rich, mud turbidites (Facies 3) are interbedded with the other facies, particularly in the mud-rich units. They have a distinctive clay and silt mineral composition that indicates derivation from the continental margin off southeast India and Sri Lanka. Biogenic turbidites (Facies 4), comprising nannofossils, foraminifers, and clay, are much less common. Two types are identified, one from the outer shelf/upper slope off Sri Lanka and the other from a local seamount source. Pelagic clays and calcareous pelagic clays (Facies 5 and 6) are developed as thin caps over some of the mud and biogenic turbidites. They mostly have a low to absent biogenic content, indicating deposition below the carbonate compensation depth for all but the last 2 m.y., as well as significant early diagenetic dissolution of siliceous microfossils. Continuously bioturbated, structureless muds of part turbidite and part pelagite aspect (Facies 7) are interpreted to have been deposited from a thick suspension cloud above and beyond the distal feather edge of the "true" turbidity current. These sediments are here termed "hemiturbidites." The effects of Himalayan uplift, eustatic and local sea-level fluctuations, local tectonics related to intraplate deformation, and fan channel/lobe processes have closely interacted to produce the observed sedimentary record of the past 17 m.y. on the Bengal Fan. Different stages of Himalayan uplift and erosion can be recognized from the composition of distal fan turbidites.

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