63 research outputs found
Holocene coastal stratigraphy, coastal changes and potential palaeoseismological implications inferred from geo-archives in Central Chile (29–32° S)
Coastal geomorphology and the stratigraphy of coastal geoarchives record past coastal and fluctuations
of coastal environments. In addition, these archives potentially store traces of past extreme events
such as earthquakes and tsunamis, severe storms, and major flfl oodings of the coastal hinterland, e.g. due to
El Niño conditions. Studying their characteristics may thus improve the knowledge of past frequency and
magnitude patterns of such extreme events. For instance, large scaled spatial information about past earthquakes
is needed for the understanding and estimation of seismo-tectonic processes. Misinterpretations in
the size of preceding earthquakes may lead to incorrect strain balance estimations along megathrusts. Thus,
fundamental research on the occurrence of past earthquakes is needed, which can be reflected in sudden or
long-term coastal changes.
Using sedimentological, geomorphological and microfaunal evidence, coeval geomorphodynamic and
palaeoenvironmental changes at four different locations between 29° 50′ and 32° 20′ S in Central Chile were
identififi ed in estuary systems, coastal swamps and coastal plains. The results may represent possible indirect
evidence for palaeoseismicity, affecting the coastal system by vertical tectonic movements. Changes
of coastline elevation, morphodynamic activity and/or coastal environments, as well as the formation of a
liquefaction layer took place during the last c. 400 years. Moreover, major flfl ooding events related to strong
El Niño conditions are assumed to have influenced the coastal stratigraphy by depositing high energy fluvial
deposits. Our results suggest that the coastal environment, geomorphology and stratigraphy are considerably
inflfl uenced by tectonic processes in the study area; a relation of the presented fifi ndings to the 1730 Great ValparaÃso
Earthquake is assumed. In general, the findings may encourage the implementation of comparable
detailed studies, which may ultimately contribute to a better understanding of the Holocene coastal evolution
and its relation to palaeoseismicity in Central Chile
Terrestrial Laser Scanner techniques in the assessment of tsunami impact on the Maddalena peninsula (south-eastern Sicily, Italy)
Variations in the 2004 Indian Ocean tsunami deposits thickness and their preservation potential, southwestern Thailand
Radiocarbon geochronology of the sediments of the São Paulo Bight (southern Brazilian upper margin)
The post-depositional changes of the onshore 2004 tsunami deposits on the Andaman Sea coast of Thailand
Shoreline changes and high-energy wave impacts at the leeward coast of Bonaire (Netherlands Antilles)
Explicitness in translation and interpreting: A critical review and some empirical evidence (of an elusive concept)
Late Quaternary sea-level change and early human societies in the central and eastern Mediterranean Basin : an interdisciplinary review
This article reviews key data and debates focused on relative sea-level changes since the Last Interglacial (approximately the last 132,000 years) in the Mediterranean Basin, and their implications for past human populations. Geological and geomorphological landscape studies are critical to archaeology. Coastal regions provide a wide range of resources to the populations that inhabit them. Coastal landscapes are increasingly the focus of scholarly discussions from the earliest exploitation of littoral resources and early hominin cognition, to the inundation of the earliest permanently settled fishing villages and eventually, formative centres of urbanisation. In the Mediterranean, these would become hubs of maritime transportation that gave rise to the roots of modern seaborne trade. As such, this article represents an original review of both the geo-scientific and archaeological data that specifically relate to sea-level changes and resulting impacts on both physical and cultural landscapes from the Palaeolithic until the emergence of the Classical periods. Our review highlights that the interdisciplinary links between coastal archaeology, geomorphology and sea-level changes are important to explain environmental impacts on coastal human societies and human migration. We review geological indicators of sea level and outline how archaeological features are commonly used as proxies for measuring past sea levels, both gradual changes and catastrophic events. We argue that coastal archaeologists should, as a part of their analyses, incorporate important sea-level concepts, such as indicative meaning. The interpretation of the indicative meaning of Roman fishtanks, for example, plays a critical role in reconstructions of late Holocene Mediterranean sea levels. We identify avenues for future work, which include the consideration of glacial isostatic adjustment (GIA) in addition to coastal tectonics to explain vertical movements of coastlines, more research on Palaeolithic island colonisation, broadening of Palaeolithic studies to include materials from the entire coastal landscape and not just coastal resources, a focus on rescue of archaeological sites under threat by coastal change, and expansion of underwater archaeological explorations in combination with submarine geomorphology. This article presents a collaborative synthesis of data, some of which have been collected and analysed by the authors, as the MEDFLOOD (MEDiterranean sea-level change and projection for future FLOODing) community, and highlights key sites, data, concepts and ongoing debates
Coastal environments from polar regions to the tropics: a geographer’s zonality perspective
The holocene paleo-tsunami history of Western Australia
West Australian coastlines experienced several tsunamis in mid-Holocene times. To expand our knowledge about Holocene tsunami events in West Australia, the authors extended the previously studied spatial scale to include the central- and south-western coastlines. Several of the discovered events were mid- and young Holocene (≤ 1000 yr BP) tsunami impacts on the outer coast of the Cape Range Peninsula. Five hundred kilometres to the south between Cape Cuvier and Point Quobba, additional tsunami evidence exists on top of steep cliffs over a coastal stretch of 30 km. The sedimentary signature of two tsunamis is documented in this area by wide ridges comprised of sand, shell, and clasts (including coral fragments) at heights of 12–30 m asl and 300–500 m inland. Enigmatic boulders (20–100 tons) appear as cliff-top megaclasts up to 100 m inland. Here, radiocarbon dating revealed a minimum of two tsunami events: at 5700 yr BP with waves depositing sandy ridges far inland and at approximately 1000 yr BP with waves depositing boulders originating from the marine environment. As the first dates are congruent with previously published results for the Learmonth region 500 km to the north, we assume that the same mid-Holocene tsunami hits this long coastal section as well. The southwestern coast of West Australia from Cape Naturaliste to Albany also shows signs of impacts by extreme waves. Here, huge granite boulders (80–400 tons) were dislocated and transported to heights up to 10 m above sea level. The most prominent dislocated boulders were positioned at Merchant Rock (Cape Naturaliste National Park), at Islet near Nanarup, and in Cave Bay close to Albany
- …