Sue Dawson

• BSc Geography
• University of Dundee

Die Nordsee ist ein weitestgehend sehr flaches Nebenmeer des Atlantiks, der mit seinen passiven Ozeanrändern einer vermeintlich geringen Tsunamigefahr unterliegt. Wenngleich durch Seebeben ausgelöste Tsunamis in der Nordsee tatsächlich extrem selten sind und nur moderate Ausmaße annehmen, gibt es zahlreiche sedimentäre Spuren von Tsunamis aus dem H...

The transition between the slope and basin floor is typically marked by a slope break, in some cases causing channels to terminate and turbidity currents to undergo a loss of confinement. It is thus essential to understand how these slope breaks and losses of confinement influence the hydrodynamic evolution of turbidity currents and impact their de...

In search of new proxies to improve tsunami deposit identification, ancient DNA (aDNA) has recently started to be used to characterize microbial communities or microfossil assemblages. For instance, foraminifera aDNA can be used when carbonate tests have been dissolved after deposition to still trace the source area of a deposit and to discriminate...

The identification of paleotsunamis in the coastal geological record requires modern analogues to allow comparison. Much research has been undertaken recently on modern tsunami sedimentation patterns and processes. We describe here the principal coastal depositional settings in which modern (and older) finer-grained tsunami deposits have been ident...

Results are presented from the current experimental campaign which aims to observe the character of supercritical turbidity currents and other supercritical sediment gravity flows (SGFs) as they respond to morphological transition zones e.g. slope breaks and losses of lateral confinement. This experimental setup aims to reproduce lower slope, chann...

Results are presented from the current experimental campaign which aims to observe the character of supercritical turbidity currents and other supercritical sediment gravity flows (SGFs) as they respond to morphological transition zones, e.g. slope breaks and losses of lateral confinement. This experimental setup aims to reproduce lower slope, chan...

Sediment Gravity Flows (SGFs) are the principal agent for the transportation of sediments that are initially stored on the shelf and eventually enter into the deeper parts of sedimentary basins. The most common downslope transportation pathway-and arguably the most important-occurs as a result of gravity acting on a relatively dense sediment-water...

We explore geomorphic evidence of recent tsunamis on the east coast of Scotland.

What are tsunamis and why do they occur? To find out, we team up with leading tsunami researchers from Bangor University and the University of Dundee.

The Shetland Isles represent an ideal field laboratory for tsunami geoscience research. This is due to the widespread preservation of Holocene tsunami sediments in coastal peat deposits. This study uses published accounts of the Holocene Storegga Slide tsunami to illustrate how two different approaches – mapping of tsunami sediments and numerical m...

Little is known of hard-rock coastal landsliding in Scotland. We identify 128 individual coastal landslides or landslide complexes >50 m wide along the coasts of Shetland. Most are apparently translational slides characterized by headscarps, displaced blocks and/or debris runout, but 13 deep-seated failures with tension cracks up to 200 m inland fr...

The aim of this work is to identify and characterize microtextural signatures in silica glass grains (used as analogous to quartz) that are produced during aqueous transport at different flow velocities, with variable sediment concentrations, transport distances, and time intervals. To achieve this, an open-channel flow experiment was conducted wit...

This chapter provides a general overview of existing knowledge and information relating to the submerged prehistoric landscape and archaeology of the continental shelf of the northern North Sea and Atlantic Northwest Approaches. Relatively high-resolution mapping vector and raster data for the coast of Scotland is held by the Ordnance Survey (OS),...

Recent work has applied microtextural and heavy mineral analyses to sandy storm and tsunami deposits from Portugal, Scotland, Indonesia and the USA. We looked at the interpretation of microtextural imagery (scanning electron microscopy) of quartz grains and heavy mineral compositions. We consider inundation events of different chronologies and sour...

This report describes the work carried out on the NERC-funded project ‘Assessing the risk to the coastal and rural road network in Scotland due to the effects of storms and extreme rainfall events’ Grant Reference NE/N013034/1. The project is part of NERC’s Environmental Risks to Infrastructure Innovation Programme, which aims to utilise existing e...

https://trl.co.uk/reports/assessing-risks-infrastructure-coastal-storms-changing-climate Executive Summary This report describes the work carried out on the NERC-funded project ‘Assessing the risk to the coastal and rural road network in Scotland due to the effects of storms and extreme rainfall events’ Grant Reference NE/N013034/1. The project is...

The World Heritage Sites of Orkney, Scotland contain iconic examples of Neolithic monumentality that have provided significant information about this period of British prehistory. However, currently, a complete understanding of the sites remains to be achieved. This is, in part, because the monuments lack an adequate context within the broader pala...

We reconstruct one of the longest relative sea-level (RSL) records in north-west Europe from the north coast of mainland Scotland, using data collected from three sites in Loch Eriboll (Sutherland) that we combine with other studies from the region. Following deglaciation, RSL fell from a Lateglacial highstand of +6-8m OD (Ordnance Datum=ca. mean s...

This study applies heavy mineral analysis to the Storegga tsunami deposit across a range of locations (Whale Firth, Maggie's Kettle Loch and Scatsta Voe) in Shetland (Scotland). The usefulness of this proxy is tested in the identification and characterization of these palaeotsunami units. Furthermore, provenance relationships are established based...

http://link.springer.com/referenceworkentry/10.1007%2F978-3-642-27737-5_646-1

The study and understanding of coastal hazards is a fundamental aspect for most modern societies. The consequences of extreme events such as tsunamis are being regarded as major threats for coastal regions. The sedimentological record provides a database useful to characterize and evaluate recurrence of tsunamis, which contributes to assessing the...

The machair is a low-lying coastal grassland system with internationally recognised conservation importance, found only in parts of northern and western Scotland and Ireland. Machair soils are exposed to some of the highest mean wind-speeds in the UK and are susceptible to aeolian erosion. Samples of machair soils were collected from three transect...

The aim of this study is to discuss and to extend the characterization of (palaeo)tsunami deposits, and their source materials, based upon the detailed study of their heavy mineral assemblages. Results obtained from three distinct locations (Portugal, Scotland and Indonesia), different coastal contexts and chronologies (the tsunami events studied t...

Climate change and extreme weather events present a range of natural hazards for the islands of the Scottish Outer Hebrides. The coastline of the island of South Uist suffered extensive erosion and shoreline change as a result of a highly destructive storm during January 2005. Particular sections of coastline are susceptible to flooding that may re...

A series of very wide (up to 15 km) raised shore platforms in the Scottish Hebrides are identified and described for the first time and are considered part of a high rock platform shoreline in the western isles of Scotland described by W. B. Wright in his classic Geological Magazine paper a century ago as a ‘preglacial’ feature. Subsequent interpre...

Investigation of shallow-marine environments for submerged prehistoric archaeology can be hampered in many localities by extensive bedrock exposure and thus limited preservation potential. Using the concept of ‘seamless archaeology’ where land-based archaeology is integrated across the intertidal zone through to the offshore, a multi-disciplinary a...

A partly quantitative reconstruction is provided of the evolution of Gualan Island, a barrier island located between South Uist and Benbecula in the Scottish Outer Hebrides, using historical maps, aerial photographs, and Lidar (light detection and ranging) data. Geomorphological changes over the last approximately 200 years are described together w...

Barrier islands commonly occur in coastal plain and deltaic settings, and a variety of behavioral and stratigraphic models exist. In this paper, a 90 km long barrier island system in the Outer Hebrides of Scotland is identified for the first time. Uniquely among barrier islands, the system rests directly on a planar bedrock (gneiss) surface (a stra...

Isolation basins are natural topographic depressions that at various times in their history may be connected to or isolated from the sea by changes in relative sea-level (RSL). They provide a valuable source of data for tracking large scale (tens of meters), millennial-scale changes in RSL, as well as quiet-water depositional environments where abr...

Changes in relative sea level (RSL) and their effect on the distribution of human activity in the Forth lowland, Scotland, UK between ca 11,700 and ca 2000 calibrated years before present (BP) are examined. Block uplift of shorelines occurred over a longer period than previously thought, continuing to at least around 4700 BP. New graphs of RSL chan...

Evidence for relative sea-level changes during the middle and late Holocene is examined from two locations on the Atlantic coast of Harris, Outer Hebrides, Scotland, using morphological mapping and survey, stratigraphical, grain size and diatom analysis, and radiocarbon dating. The earliest event identified is a marine flood, which occurred after 7...

In West Greenland, early and mid Holocene relative sea level (RSL) fall was replaced by late Holocene RSL rise during the Neoglacial, after 4–3 cal. ka BP (thousand calibrated years before present). Here we present the results of an isolation basin RSL study completed near to the coastal town of Sisimiut, in central West Greenland. RSL fell from 14...

The December 26, 2004, disastrous tsunami event in the Indian Ocean may have come as a shock and even a surprise to the communities outside geosciences. However, tsunami events are a natural part of the geosystems in regions of submarine earthquakes, and they will continue to hit the region even in the future. Here we present evidence of former tsu...

Relative sea-level (RSL) observations from the margins of the Greenland Ice Sheet (GIS) provide information regarding the timing and rate of deglaciation and constraints on geophysical models of ice sheet evolution. In this paper we present the first RSL record for the southeast sector of the GIS based on field observations completed close to Ammas...

Distinctive diatom assemblages may be associated with tsunami sediments and may often contrast with the assemblages found within sediments underlying the tsunami deposit as well as those associated with the modern coastal environment. Sediments associated with the 1998 tsunami that destroyed much of the Sissano lagoon area in northern Papua New Gui...

This paper describes some of the changes that affected the coastlines of South Uist and Benbecula following the ‘Great Storm’ of 11 January 2005. The paper considers historical changes in patterns of winter storminess and addresses the issue of whether or not there has been a recent increase in regional storminess, manifested partly by this particu...

It is important, when using altimetry data to reconstruct ice sheet mass balance, to accurately remove the effects of vertical movements in the solid Earth caused by Post Glacial Rebound (PGR). Holocene relative sea- level (RSL) data constrain PGR in Greenland, but their quality and distribution is patchy. For example, one widely cited model in mas...

A distinctive sand layer enclosed within Holocene peat is described from Basta Voe, Isle of Yell, Shetland Isles. The sand layer, that can be traced considerable distances inland and up to a maximum altitude of c. + 9 m OD, is here interpreted as having been deposited by a former tsunami. AMS dating appears to indicate that the tsunami occurred bet...

The margin of the Greenland Ice Sheet retreated rapidly during the first few thousand years of the Holocene. During this period of relative warmth, known as the Holocene thermal maximum, ice core records identify a significant short-lived cooling event at approximately 8.4–8.0 ka cal. yr BP (the ‘GH-8.2 event’) associated with a 5–7 °C fall in mean...

Coastal fen- and lake deposits enclose sand layers that record at least three Holocene tsunamis at the Shetland Islands. The oldest is the well-known Storegga tsunami (ca 8100 cal yr BP), which at the Shetlands invaded coastal lakes and ran up peaty hillsides where it deposited sand layers up to 9.2m above present high tide level. Because sea level...

We provide a short report on the final year of the INQUA Shorelines Subcommission on Western Europe (2002-3). This includes a review of activities under four themes: sea-level changes in the next century; sea-level changes along a north-south transect from the uplifting coasts of Fennoscandanvia to the subsiding coasts of the North Sea and the Balt...

All currently known sites in the United Kingdom with evidence for the Holocene Storegga Slide tsunami are described. Information on the altitude, distribution, stratigraphical context, age, particle size profile and microfossil characteristics of the deposits is presented. The tsunami involved a greater area than previously described, reaching a co...

Lithostratigraphical and biostratigraphical investigation of coastal marshes along the Atlantic coast of the Outer Hebrides from Lewis in the north to Barra in the south discloses inland-tapering sand units within marshland areas. The inland extent of each sand unit has been radiometrically dated and the units have been collectively interpreted as...

Synopsis Detailed morphological, lithostratigraphical and biostratigraphical studies in the lower Nith valley and estuary, Scotland, disclose evidence for changing relative sea levels during the Holocene. The Main Postglacial Transgression was in progress in the area around c. 7500 ¹⁴ C years bp (8350 cal. years bp ) to c. 7800 ¹⁴ C years bp ( c ....

One of the largest Holocene sub-marine slides mapped on Earth is the Storegga slide offshore Norway [Bugge, 1987] (Figure 1). Approximately 3500 km3 material slid out and generated a huge tsunami dated to about 7300 14C yr BP [Bondevik et al., 1997a], or ca 8150 calendar years BP. The tsunami is known from onshore deposits in Norway [Bondevik et al...

A sub-aqueous earthquake may set up a tsunami wave. When breaking in over a coastal area, this wave will rise to considerable height and flush in over land providing both an on-swash and a back-swash signal in bordering lakes. The tsunami beds are usually identified as sandy-gravelly layers, often in fining-upward sequence, and, most important, con...

The INQUA Maldives Project started in 2000. Prior to that, quite little was know about the actual changes in past sea level in the Maldives. In the IPCC project, low-lying areas and especially the Maldives have been condemned to become flooded in 50-100 years. With respect to multiple integrated sea level processes, the Maldives have a uniquely pos...

Changes in Holocene (Flandrian) relative sea levels and coastal geomorphology in the lower Cree valley and estuary, SW Scotland, are inferred from detailed morphological and stratigraphical investigations. A graph of relative sea level changes is proposed for the area. Rising relative sea levels during the early Holocene were interrupted at c. 8300...

Sediment cores collected in a coastal lagoon a few kilometres east of Wairoa, northern Hawke's Bay, New Zealand, were examined using sedimentological, geochemical, palynological and micropaleontological analyses.A distinct short-lived catastrophic saltwater inundation (CSI) about 6300 years BP and possibly other minor marine incursions are preserve...

Previous reports have suggested a link between increased storminess in the North Atlantic during recent years with a period of time during which the North Atlantic Oscillation Index has been strongly positive. New analyses of late nineteenth-century gale-day data for meteorological stations in northern Scotland and western Ireland indicate that the...

Synopsis An intertidal organic deposit is described for Traigh Eileraig, Isle of Coll, Scottish Inner Hebrides. The organic sediments are overlain by sands containing marine diatoms. Radiocarbon dating and diatom analysis indicate that a relative marine transgression took place in Coll at c. 8000 ¹⁴ C years bp , an interpretation consistent with th...

The Iggeesund event is an example of the high seismicity which occurred in Fennoscandia during deglaciation as a function of the high rate of glacial isostatic uplift. This event is dated to varve 9663 BP. The Iggesund–Hudiksvall area is represented by intensive postglacial fracturing of the bedrock recorded over an area of, at least, 50×50 km. The...

Lagoonal sediments attributed to the main Holocene marine transgression in Strath Halladale, northern Sutherland, contain a complex coarser layer believed to have been deposited during the tsunami associated with the Second Storegga Slide off South West Norway. The coarser sequence is dated at between 7590±50 and 7290±50 radiocarbon years BP (6507–...

The geomorphic and sedimentological evidence for former sea-level changes in the exposed coastline of western Jura shows a clear coastal response to past changes in climate. In particular the rapid and high-magnitude climate changes associated with the onset and termination of the Younger Dryas appear to have been accompanied by major changes in co...

Litho- and biostratigraphic analyses undertaken in the Gruinart estuary, central Islay, reveal a detailed sedimentary record of Holocene relative sea-level changes and high-energy flood events during the last 10 000 years. During the Lateglacial-Holocene transition relative sea level had fallen to below c. 0.5 m OD and remained at this depth until...

Evidence is presented for Holocene relative sea-level changes on the margin of a glacio-isostatically uplifted area: the lower Wick River valley, northern Caithness, Scotland. Lithostratigraphic, biostratigraphic and chronostratigraphic analyses of intercalated clastic and organic sediments disclose evidence for a rapid rise of relative sea level f...

This paper presents the second detailed study of sediments deposited by modern tusnamis, the first being that of the Flores (Indonesia) tsunami of December 1992 (Shi et al., 1995). Sediment cores were collected from areas in which eyewitnesses reported sediment deposition. Grain size analysis shows pronounced vertical variations in grain size as we...

The interpretation of diatom biostratigraphy is a little used technique in the study of onshore tsunami sedimentation. Evidence is presented from examples from three tsunamis in which sediments were either observed to have been deposited; documentary evidence attests to the presence of sediment sheets, or finally, in the case of palaeo tsunamis, mo...