Journal articles: 'Marine sediments Underwater archaeology'

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Papatheodorou, George, Maria Geraga, Dimitris Christodoulou, Elias Fakiris, Margarita Iatrou, Nikos Georgiou, Xenophon Dimas, and George Ferentinos. "The Battle of Lepanto Search and Survey Mission (1971–1972) by Throckmorton, Edgerton and Yalouris: Following Their Traces Half a Century Later Using Marine Geophysics." Remote Sensing 13, no. 16 (August 20, 2021): 3292. http://dx.doi.org/10.3390/rs13163292.

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A series of marine remote sensing and ground-truth surveys were carried out at NW Gulf of Patras (W. Greece). The same area was surveyed in 1971 by Throckmorton, Edgerton and Yalouris, who are among the pioneers in the application of remote sensing techniques to underwater archaeology. The researchers conducted a surface reconnaissance survey to locate the site where the Battle of Lepanto took place on 7 October 1571. Their remote sensing surveying resulted in a map of two “target” areas that showed promise as possible remnants of wrecks from that battle and proposed a ground truth survey for their identification and in the detection of two modern shipwrecks. The ground truth survey was never fulfilled. The objectives of our repeat surveys, which were completed 50 years later, were to relocate the findings of this pioneer survey with higher spatial and vertical resolution, to ground-truth the targets, fulfilling their investigation, and to interpret the newly collected data in the light of modern developments in marine geosciences. Our repeat surveys detected mound clusters and individual mounds referred to “target” areas. These mounds could be interpreted as the surface expression of mud and fluid expulsion from the underlying deformed soft sediments. The ground truth survey demonstrated that the tops of mounds represent biogenic mounds. The ROV survey did not show any indication of wreck remnants of the Battle of Lepanto within the two survey areas. The site formation processes of the two modern shipwrecks were also studied in detail. Two noticeable seafloor morphological features were detected around the wreck sites; field of small-sized pockmarks and seafloor depressions. We would like to dedicate this work to the memory of Peter Throckmorton and Harold E. Edgerton, who are among the pioneers in the formative years of underwater archaeology in Greece.

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Selig, ET, and RC Circé. "An Underwater Instrument for Determining Bearing Capacity of Shallow Marine Sediments." Geotechnical Testing Journal 8, no. 2 (1985): 96. http://dx.doi.org/10.1520/gtj10516j.

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Ødegård, Øyvind, Aksel Alstad Mogstad, Geir Johnsen, Asgeir J. Sørensen, and Martin Ludvigsen. "Underwater hyperspectral imaging: a new tool for marine archaeology." Applied Optics 57, no. 12 (April 18, 2018): 3214. http://dx.doi.org/10.1364/ao.57.003214.

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BAILEY, G., and N. FLEMMING. "Archaeology of the continental shelf: Marine resources, submerged landscapes and underwater archaeology." Quaternary Science Reviews 27, no. 23-24 (November 2008): 2153–65. http://dx.doi.org/10.1016/j.quascirev.2008.08.012.

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Wang, Y. G., C. C. Liao, J. H. Wang, and W. Wang. "Numerical study for dynamic response of marine sediments subjected to underwater explosion." Ocean Engineering 156 (May 2018): 72–81. http://dx.doi.org/10.1016/j.oceaneng.2018.01.106.

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Liao, C. C., Yaguang Wang, Jinjian Chen, and Qi Zhang. "Parametric study for underwater blast-induced pipeline response embedded in marine sediments." Marine Georesources & Geotechnology 37, no. 9 (November 14, 2018): 1071–82. http://dx.doi.org/10.1080/1064119x.2018.1526831.

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Fletcher-Tomenius, P., PJ O'Keefe, and M. Williams. "Salvor in possession: friend or foe to marine archaeology." International Journal of Cultural Property 9, no. 2 (January 2000): 263–314. http://dx.doi.org/10.1017/s0940739100771086.

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While the threat to the underwater cultural heritage from the treasure salvage industry is widely recognised, the approach to 'protection' ranges from absolute prohibition to the sale of state licences to the highest bidder. Even the former raises difficult problems of enforceability and the choice of mechanisms to determine whether in situ preservation is the preferred option for any particular wreck site. The common law jurisdictions have tended to prefer a regulated salvage regime, in which the courts themselves have a role in considering whether appropriate archaeological methodology is applied to the recovery of historic artefacts. This article examines the legal and economic basis of such an approach and evaluates whether the underwater cultural heritage has derived any discernible benefit from this judicial creativity. Inter alia, it concludes that the legal framework is itself flawed by uncertainty and that the deliberations of the court are hampered by procedural deficiencies.

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Godin, Oleg A., and David M. F. Chapman. "The effect of marine sediments on the underwater penetration of a sonic boom." Journal of the Acoustical Society of America 114, no. 4 (October 2003): 2450. http://dx.doi.org/10.1121/1.4809229.

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Morgenstern, U., M. A. Geyh, H. R. Kudrass, R. G. Ditchburn, and I. J. Graham. "32Si Dating of Marine Sediments from Bangladesh." Radiocarbon 43, no. 2B (2001): 909–16. http://dx.doi.org/10.1017/s0033822200041576.

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Appropriate dating tools are essential for paleoenvironmental studies. Cosmogenic 32Si with a half-life of about 140 years is ideally suited to cover the dating range 30–1000 years. Here we have applied scintillation spectrometry for detection of natural 32Si to date marine shelf sediments. High detection efficiency, combined with stable background, allows for the detection of extremely low 32Si specific activities found in such sediments with counting rates below one count per hour. For a sediment core from the Ganges-Brahmaputra delta 32Si dating yields mean sedimentation rates of 0.7 ± 0.2 cm/yr for 50 to several hundred years BP and 3.1 ± 0.8 cm/yr for the past 50 years. The four-fold increase of the sedimentation rate over the past 50 years may reflect increased sediment loads in the rivers due to increasing human colonization within the rivers' drainage basins.

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JACOBS, ZENOBIA. "Luminescence chronologies for coastal and marine sediments." Boreas 37, no. 4 (November 2008): 508–35. http://dx.doi.org/10.1111/j.1502-3885.2008.00054.x.

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Ludvigsen, Martin, Bjørn Sortland, Geir Johnsen, and Hanumant Singh. "Applications of Geo-Referenced Underwater Photo Mosaics in Marine Biology and Archaeology." Oceanography 20, no. 4 (December 1, 2007): 140–49. http://dx.doi.org/10.5670/oceanog.2007.14.

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Croff, Katherine L. "The Underwater Cultural Heritage and Marine Scientific Research in the Exclusive Economic Zone." Marine Technology Society Journal 43, no. 1 (March 1, 2009): 93–100. http://dx.doi.org/10.4031/mtsj.43.1.6.

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AbstractThis paper reviews the relationship between activities aimed at the underwater cultural heritage and marine scientific research in the exclusive economic zone, in particular the question of whether or not underwater cultural heritage research can be classified as marine scientific research. The study examines the definitions, practice, and jurisdiction of each, according to the Third UN Conference on the Law of the Sea, the UNESCO Convention on the Protection of the Underwater Cultural Heritage, and States’ current practice. By revising the current interpretation of international law, underwater cultural heritage research can potentially be classified as marine scientific research. The inclusion of archaeology as marine science would have implications that would open up new rights and responsibilities of coastal and research States, as both fulfill their duties to protect and preserve archaeological and historical objects found on the seabed.

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BERGSTEN, HELENE, and KJELL NORDBERG. "Middle Weichselian marine sediments from eastern Kattegat, Scandinavia." Boreas 22, no. 4 (January 16, 2008): 311–18. http://dx.doi.org/10.1111/j.1502-3885.1993.tb00191.x.

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Benjamin, Jonathan, and Alex Hale. "Marine, Maritime, or Submerged Prehistory? Contextualizing the Prehistoric Underwater Archaeologies of Inland, Coastal, and Offshore Environments." European Journal of Archaeology 15, no. 2 (2012): 237–56. http://dx.doi.org/10.1179/1461957112y.0000000007.

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Studies in submerged prehistoric archaeology have gained momentum in recent years with particular focus on the inundated landscapes of the European continental shelf. Although this renewed interest lies primarily in modern coasts and seas, there are a variety of differences between the submerged prehistoric archaeologies of inland and marine environments, ranging from questions of scientific research to heritage management to practical field methods. Some of these differences are the result of location, function, and period. Despite this, there exist similarities that, if ignored, risk increased marginalization of the archaeology of submerged landscapes from the greater field of prehistoric archaeology. A holistic evaluation of prehistoric archaeological landscapes must include inland waters and coastal zones and their relationships. Aquatic environments, viewed both as individual locations as well as continuous and connecting waterways, are introduced for their differences and similarities, and simplified examples of material and legislation are introduced in order to contextualize submarine sites and practices within the greater fields of prehistory and underwater archaeology.

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Bender, Ken, and Robert T. Farrell. "1989 underwater archaeological investigations at the Shoals Marine Laboratory, Appledore Island, Maine." International Journal of Nautical Archaeology 19, no. 3 (August 1990): 259–60. http://dx.doi.org/10.1111/j.1095-9270.1990.tb00273.x.

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Coleman, Dwight F. "Underwater Archaeology in Thunder Bay National Marine Sanctuary, Lake Huron—Preliminary Results from a Shipwreck Mapping Survey." Marine Technology Society Journal 36, no. 3 (September 1, 2002): 33–44. http://dx.doi.org/10.4031/002533202787913387.

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Off northeastern Lower Michigan, the bottom waters of Lake Huron in the Thunder Bay National Marine Sanctuary and Underwater Preserve (TBNMS/UP) contain a vast array of historic shipwrecks representing more than a century of early Great Lakes shipping. During June 2001, in collaboration with the National Oceanic and Atmospheric Administration (NOAA) and the State of Michigan, the Institute for Exploration (IFE) mapped a large portion of “Shipwreck Alley”, which extends throughout the deep-water portion of the Sanctuary and continues farther north. Seventeen shipwrecks, two of which are new discoveries, and many other interesting lakebed features were acoustically imaged and carefully surveyed using a high-frequency side-scan sonar towfish. In addition, a number of submerged sinkholes and lakebed pockmarks were discovered and mapped. These karst features in the limestone bedrock were exposed subaerially from about 10000 to 8000 years ago, when the lake level was substantially lower following the last glacial maximum. The archaeological significance of these sinkholes, the newly discovered shipwrecks, and several other promising sonar targets will be evaluated when IFE returns to TBNMS/UP in 2002. Using a remotely operated vehicle (ROV) and an advanced underwater imaging platform, we will visually survey the most important sites, collect high-definition underwater video, and ground-truth sonar targets. The work will be performed by marine geologists in collaboration with underwater archaeologists and maritime historians. This effort is part of a long-term scientific, educational, and public outreach project in the TBNMS/UP supported by NOAA's National Marine Sanctuary Program and Office of Ocean Exploration.

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Androulakaki, E. G., C. Tsabaris, M. Kokkoris, G. Eleftheriou, D. L. Patiris, F. Pappa, and R. Vlastou. "Progress in radionuclide characterisation in marine sediments using an underwater gamma-ray spectrometer in 2π geometry." HNPS Proceedings 21 (March 8, 2019): 29. http://dx.doi.org/10.12681/hnps.2000.

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The in-situ gamma-ray spectrometry is a well suited method for seabed mapping applications, since it provides rapid results in a cost effective manner. Moreover, the in-situ method is preferable to the commonly applied laboratory measurements, due to its beneficial characteristics. Therefore, the development of in-situ systems for seabed measurements continuously grows. However, an efficiency calibration of the detection system is necessary for obtaining quantitative results in the full spectral range. In the present work, an approach for calculating the full-energy peak efficiency of an underwater insitu spectrometer for measure- ments on the seabed is presented. The experimental work was performed at the coastal site of Vasilikos (Cyprus). The experimental full-energy peak efficiency of the in-situ was determined in the energy range 1400–2600 keV, by combining the in-situ and laboratory reference measurements. The experimental effi- ciency results were theoretically reproduced by means of Monte Carlo (MC) simulations, using the MCNP5 code.

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Ferrari, Ben, and Jon Adams. "Biogenic modifications of marine sediments and their influence on archaeological material." International Journal of Nautical Archaeology 19, no. 2 (May 1990): 139–51. http://dx.doi.org/10.1111/j.1095-9270.1990.tb00247.x.

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19

Roy, Peter S. "Shell Hash Dating and Mixing Models for Palimpsest Marine Sediments." Radiocarbon 33, no. 3 (1991): 283–89. http://dx.doi.org/10.1017/s0033822200040303.

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The dating of palimpsest marine sediments using broken shell fragments (shell hash) is considered to be a necessary but unreliable technique because of the mixed age of the fragments. An analysis of geological mixing models and radiocarbon data on shell hash from sandy sediments on the southeast Australian coast and shelf are used to examine the possibility for simulating the depositional processes, and thus, to better understand the age structure of the deposits.

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Papatheodorou, G., M. Geraga, A. Chalari, D. Christodoulou, M. Iatrou, E. Fakiris, St Kordella, M. Prevenios, and G. Ferentinos. "Remote sensing for underwater archaeology: case stud-ies from Greece and Eastern Mediterranean." Bulletin of the Geological Society of Greece 44 (February 1, 2017): 100. http://dx.doi.org/10.12681/bgsg.11440.

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Modern underwater remote sensing technology introduces many advantages that extend the range of conventional diving work providing the means to survey in a detailed and systematic fashion large seafloor area. There are two general approaches regarding the application of these techniques in underwater archaeology; they are being increasingly used to identify, locate and map (i) ancient and historical shipwrecks lying on the seafloor or partly buried in it and (ii) the coastal palaeogeogra-phy and thus submerged sites of archaeological interest (submerged ancient cities, settlements, ports and man-made structures). The underwater remote sensing techniques most commonly applied to underwater archaeology employ: (i) single and multi-beam echosounders (ii) side scan sonar (acousting imaging), (iii) laser line scan (optical imaging) (iv) subbottom profiler, (v) marine magne-tometer and (vi) undersea vehicles. The objectives of this paper are twofold: (i) to present the results of remote sensing surveys that carried out at sites of archaeological and historical interest, in Greece (Dokos Island, ancient harbour of Kyllene and Navarino Bay whereas a historical naval Battle took place) and in Eastern Mediterranean Sea (Alexandria Egypt and Mazotos shipwreck Cyprus), and (ii) to prove the applicability of remote sensing techniques in underwater archaeology showing that a combination of these can be a very effective tool.

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Igarashi, Yaeko. "Quaternary forest and climate history of Hokkaido, Japan, from marine sediments." Quaternary Science Reviews 13, no. 4 (January 1994): 335–44. http://dx.doi.org/10.1016/0277-3791(94)90111-2.

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Quintino, Victor, Rosa Freitas, Renato Mamede, Fernando Ricardo, Ana Maria Rodrigues, Jorge Mota, Ángel Pérez-Ruzafa, and Concepción Marcos. "Remote sensing of underwater vegetation using single-beam acoustics." ICES Journal of Marine Science 67, no. 3 (November 13, 2009): 594–605. http://dx.doi.org/10.1093/icesjms/fsp251.

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Abstract Quintino, V., Freitas, R., Mamede, R., Ricardo, F., Rodrigues, A. M., Mota, J., Pérez-Ruzafa, Á., and Marcos, C. 2010. Remote sensing of underwater vegetation using single-beam acoustics. – ICES Journal of Marine Science, 67: 594–605. A single-beam, acoustic, ground-discrimination system (QTC VIEW, Series V) was used to study the distribution of underwater macrophytes in a shallow-water coastal system, employing frequencies of 50 and 200 kHz. The study was conducted in Mar Menor, SE Spain, where the expansion of Caulerpa prolifera has contributed to the silting up of the superficial sediments. A direct relationship was identified between algal biomass and sediment-fines content. Acoustic information on sediment grain size and data on algal biomass were obtained in muddy and sandy sediments, including vegetated and non-vegetated seabed. Non-vegetated muddy areas were created by diving and handpicking the algae. The multivariate acoustic data were analysed under the null hypotheses that there were no acoustic differences between bare seabeds with contrasting superficial sediment types or among low, medium, and high algal-biomass areas, having in mind that grain size can act as a confounding factor. Both null hypotheses were rejected, and the results showed that 200 kHz was better than 50 kHz in distinguishing cover levels of algal biomass. The relationship between the 200-kHz acoustic data and algal biomass suggests utility in modelling the latter using the former.

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Pedan, G. S., S. V. Kadurin, K. P. Andreeva, and O. V. Dragomyretska. "LITHOLOGY AND HYDRODYNAMICS OF THE BLACK SEA ODESSA COAST UNDERWATER PART." Odesa National University Herald. Geography and Geology 26, no. 1(38) (September 4, 2021): 220–32. http://dx.doi.org/10.18524/2303-9914.2021.1(38).234714.

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Problem Statement and Purpose. The results of lithological studies, including granulometric analysis, are needed to identify the conditions of sedimentation and distribution of rock fragments by size. They are an indicator of the sedimentation processes dynamic structure peculiarities. The study of the sediment regime is important for the development of measures related to the protection of shores from erosion. The aim of the work is to identify the lithological features of the bottom sediment types distribution on the protected section of the Odessa coast near Cape Maly Fontan. Data & Methods. The materials for this work were obtained in the field research in the summer 2019 in the coastal zone between the hydrobiological station of Odessa I. I. Mechnikov National University, and Cape Malyj Fountain. Three measuring profiles were made perpendicular to the shoreline at 1200 m towards the sea to a depth of 18 m. 35 samples were taken from the upper layer of bottom sediments. Field samples processing was performed in the Problem Research Laboratory of Engineering Geology of the Sea Coast, Reservoirs and Mountain Slopes of Odessa I. I. Mechnikov National University. Granulometric classification was performed. Excel, Statistica, Golden Software Surfer programs were used to process the results. Results. Underwater relief analysis showed that the coastal part is an abrasive terrace, on which ancient landslides relics are widespread. There are 7 main lithological types of bottom sediments detected. The largest areas covered by fine-grained loamy sands and shell detritus with gravel, pebbles and sand. Analysis of distribution curves and cumulative curves of granulometric distribution showed that coarse sediments are characterized by multi-vertex distribution curves and stepwise stretched cumulative curves, which indicates the heterogeneity of sediments in granulometric distribution. For fine-grained material, which is well sorted, the distribution curves are almost single-vertex, and the cumulative curves have a large steepness and a simple, non-stepped shape. There are three hydrodynamic detected in bottom sediments lithology according on statistical parameters of grain size. Outer marine part with depth more than 15 meters characterized by low hydrodynamic processes and presented by good-sorted sands and silt. The central part of polygon in 4–15 meters depth covered by shell detritus with gravel and pebble of carbonate rocks and connected with rocky extrusions after coastal landslides. The feature of this part is active hydrodynamic processes. The rocky extrusions presented like natural breakwater and due to waves braking and collection of different types of sediments. The coastal part in 2–4 m depth in front of constructed breakwater leads to decreasing of wave energy and sedimentation of good-sorted sands.

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Björdal, Charlotte Gjelstrup, David Gregory, Martijn Manders, Zyad Al-Hamdani, Christin Appelqvist, Jon Haverhand, and Jörgen Dencker. "Strategies for Protection of Wooden Underwater Cultural Heritage in the Baltic Sea Against Marine Borers. The EU Project ‘WreckProtect’." Conservation and Management of Archaeological Sites 14, no. 1-4 (November 2012): 201–14. http://dx.doi.org/10.1179/1350503312z.00000000017.

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Kapetanović, Nadir, Antonio Vasilijević, Đula Nađ, Krunoslav Zubčić, and Nikola Mišković. "Marine Robots Mapping the Present and the Past: Unraveling the Secrets of the Deep." Remote Sensing 12, no. 23 (November 28, 2020): 3902. http://dx.doi.org/10.3390/rs12233902.

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Underwater cultural heritage sites are subject to constant change, whether due to natural forces such as sediments, waves, currents or human intervention. Until a few decades ago, the documentation and research of these sites was mostly done manually by diving archaeologists. This paper presents the results of the integration of remote sensing technologies with autonomous marine vehicles in order to make the task of site documentation even faster, more accurate, more efficient and more precisely georeferenced. It includes the integration of multibeam sonar, side scan sonar and various cameras into autonomous surface and underwater vehicles, remotely operated vehicle and unmanned aerial vehicle. In total, case studies for nine underwater cultural heritage sites around the Mediterranean region are presented. Each case study contains a brief archaeological background of the site, the methodology of using autonomous marine vehicles and sensors for their documentation, and the results in the form of georeferenced side-scan sonar mosaics, bathymetric models or reconstructed photogrammetric models. It is important to mention that this was the first time that any of the selected sites were documented with sonar technologies or autonomous marine vehicles. The main objective of these surveys was to document and assess the current state of the sites and to establish a basis on which future monitoring operations could be built and compared. Beyond the mere documentation and physical preservation, examples of the use of these results for the digital preservation of the sites in augmented and virtual reality are presented.

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Zhang, Jinzhao, Hongzhi Li, and Xianguo Tuo. "In-Situ Measurement of Artificial Nuclides in Seabed Sediments Based on Monte Carlo Simulations and an Underwater HPGe Detector." Marine Technology Society Journal 53, no. 3 (May 1, 2019): 16–22. http://dx.doi.org/10.4031/mtsj.53.3.1.

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AbstractIn-situ measurement of marine sediment radioactivity does not destroy the stratification of radionuclides in the sediment. We develop a novel seabed sediment radioactive measurement technique using a High Purity Germanium (HPGe) detector. The overall measurement system is designed, and the detector energy calibration is performed. The efficiency is calculated based on Monte Carlo simulations using the MCNP5 code. We compared the efficiency and energy resolution with the NaI(Tl) detection through experiments. NaI(Tl) detection is incapable of identifying the 137Cs artificial nuclides in seabed sediments due to the energy resolution limit. Hence, underwater HPGe detection is utilized due to its high energy resolution, which enables the detection of artificial nuclides 137Cs. The proposed method is of great significance in evaluating marine radioactive pollution.

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Forman, Steven L., Kenneth Lepper, and James Pierson. "Limitations of infra-red stimulated luminescence in dating high Arctic marine sediments." Quaternary Science Reviews 13, no. 5-7 (January 1994): 545–50. http://dx.doi.org/10.1016/0277-3791(94)90075-2.

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Mensing, Scott A., and John R. Southon. "A Simple Method to Separate Pollen for AMS Radiocarbon Dating and its Application to Lacustrine and Marine Sediments." Radiocarbon 41, no. 1 (1999): 1–8. http://dx.doi.org/10.1017/s0033822200019287.

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We present a simple method for manually separating pollen concentrates for radiocarbon accelerator mass spectrometry (AMS) dating using a mouth pipetting system. The required equipment is readily available from scientific equipment supply houses at minimal cost. Pollen samples from lake sediments required about 4 h of hand picking, whereas samples from marine sediments required about 8 h labor. Pollen dates from marine sediments were much older than expected. We are attempting to resolve whether this is due to contamination of the pollen or the presence of significant quantities of old reworked pollen. Pollen dates from lake sediments associated with Mazama Ash were consistent with other published ages; however, replicate dates on pollen samples from above the ash were consistently older than the surrounding sediment. Our results suggest that caution must be used when interpreting pollen dates if the potential for sediment reworking is present.

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Wang, Yuan, Zhiwei Li, Jianhua Geng, Qingyu You, Tianyao Hao, Yaoxing Hu, Chunlei Zhao, Yan Zhang, and Yuzhu Liu. "Seismic imaging of S-wave structures of shallow sediments in the East China Sea using OBN multicomponent Scholte-wave data." GEOPHYSICS 85, no. 6 (October 21, 2020): EN87—EN104. http://dx.doi.org/10.1190/geo2019-0639.1.

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The shear-wave (S-wave) structures of shallow marine sediments are important for offshore geotechnical studies, deep crustal S-wave imaging, multicomponent seismic exploration, and underwater acoustics studies. We have applied the multicomponent Scholte-wave analysis technique to an active-source shallow marine seismic profile in the East China Sea. Scholte waves have been excited by shots from a 5450 inch3 air-gun array and their recordings have been conducted at the seafloor using ocean bottom nodes (OBNs). First, we extract the common-receiver gathers (CRGs) and correct for the time drift simultaneously using a forward and inverse fast Fourier transform resampling algorithm. Three CRGs of seismic sensors are used for Scholte-wave analysis. Raw sensor CRGs are rotated to the inline, crossline, and vertical coordinate system. The rotated tilt and roll angle are directed using the inner electric compass log value, and the shot inline azimuth is estimated using the particle motion method. Then, the velocity spectra are calculated from the inline and vertical components using the phase-shift method. Higher Scholte-wave modes dominate on the horizontal components, whereas the stronger fundamental mode dominates on the vertical components. The multicomponent velocity spectrum stacking method is adopted to produce the final dispersion energy image. Up to four modes of dispersion curves are retrieved within the 1.1–4.3 Hz frequency band. The multimode dispersion curve inversion is constructed for imaging the shallow sediments. The results suggest a low [Formula: see text] of 180–650 m/s and few lateral variations within the top 0.5 km of shallow marine sediments in the East China Sea. This model can provide an important reference for offshore geotechnical investigations, especially for OBN multicomponent seismic exploration data processing. The use of OBNs has high feasibility in [Formula: see text] imaging for shallow marine sediments when combined with the Scholte-wave dispersion-curve inversion.

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Androulakaki, E., C. Tsabaris, D. L. Patiris, G. Eleftheriou, M. Kokkoris, and R. Vlastou. "In situ gamma-ray measurements of marine sediment using Monte Carlo simulation." HNPS Proceedings 20 (December 1, 2012): 139. http://dx.doi.org/10.12681/hnps.2499.

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This work outlines the progress in developing a new method for in situ radioactivity measurements of marine sediments. The method combines the underwater gamma-ray spectrometer (a system named KATERINA based on a NaI(Tl) detector) with Monte-Carlo calculations using the MCNP5 code. This method aims at allowing for an accurate quantitative determination of activity concentrations in marine sediments (using the in situ system), which can be applied in different areas and for variable sediment structures.As a first step, the MCNP5 code has been successfully applied for the standard 4π geometry in the aquatic environment, reproducing results of the marine efficiency as previously deduced by the GEANT4 code. The experimental set up geometry was introduced in MCNP5 using detailed information for the geometry and the materials. Moreover, a first simulated estimation of the in situ efficiency for sediment measurements is presented for 40K (1460.8 keV). For this purpose a new model was constructed taking into account a typical experimental geometry set-up (with the detector being situated in close contact with the seabed). In order to validate the Monte-Carlo results, activity measurements were also performed in sediment samples collected from Basilica, Cyprus, where the in situ system was deployed. The samples were analysed using a HPGe detector for inter-calibration purposes and the obtained results are discussed.

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Mollenhauer, Gesine, Daniel Montluçon, and Timothy I. Eglinton. "Radiocarbon Dating of Alkenones from Marine Sediments: II. Assessment of Carbon Process Blanks." Radiocarbon 47, no. 3 (2005): 413–24. http://dx.doi.org/10.1017/s0033822200035190.

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We evaluate potential process blanks associated with radiocarbon measurement of microgram to milligram quantities of alkenones at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. Two strategies to constrain the contribution of blanks to alkenone 14C dates were followed: 1) dating of samples of known age and 2) multiple measurements of identical samples. We show that the potential contamination associated with the procedure does not lead to a systematic bias of the results of alkenone dating to either younger or older ages. Our results indicate that alkenones record Δ14C of ambient DIC with an accuracy of approximately 10‰. A conservative estimate of measurement precision is 17‰ for modern samples. Alkenone 14C ages are expected to be reliable within 500 yr for samples younger than 10,500 14C yr.

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Morello, Elisabetta B., Carlo Froglia, and R. J. A. Atkinson. "Underwater television as a fishery-independent method for stock assessment of Norway lobster (Nephrops norvegicus) in the central Adriatic Sea (Italy)." ICES Journal of Marine Science 64, no. 6 (July 21, 2007): 1116–23. http://dx.doi.org/10.1093/icesjms/fsm082.

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Abstract Morello, E. B., Froglia, C., and Atkinson, R. J. A. 2007. Underwater television as a fishery-independent method for stock assessment of Norway lobster (Nephrops norvegicus) in the central Adriatic Sea (Italy). – ICES Journal of Marine Science, 64: 1116–1123. Norway lobster is of great commercial importance throughout the NE Atlantic and Mediterranean, where it lives in burrows in muddy sediments. The fact that the species is caught in commercial gear only when it emerges from its burrow and the absence of hard structures available for age determination complicate the application of normal fishery-dependent stock-assessment methodologies. This study provides more evidence of the usefulness of underwater television surveys as a fishery-independent technique to assess the Nephrops stocks of the Adriatic Sea. The results are compared with those of previous studies, and the advantages and disadvantages of using such methodology discussed in an Adriatic context.

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Hopkins, Jenni L., Richard J. Wysoczanski, Alan R. Orpin, Jamie D. Howarth, Lorna J. Strachan, Ryan Lunenburg, Monique McKeown, Aratrika Ganguly, Emily Twort, and Sian Camp. "Deposition and preservation of tephra in marine sediments at the active Hikurangi subduction margin." Quaternary Science Reviews 247 (November 2020): 106500. http://dx.doi.org/10.1016/j.quascirev.2020.106500.

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Choi, J. H., A. S. Murray, M. Jain, C. S. Cheong, and H. W. Chang. "Luminescence dating of well-sorted marine terrace sediments on the southeastern coast of Korea." Quaternary Science Reviews 22, no. 2-4 (February 2003): 407–21. http://dx.doi.org/10.1016/s0277-3791(02)00136-1.

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Rodrigues, Luiz F., Kita D. Macario, Roberto M. Anjos, João M. M. Ketzer, Anderson J. Maraschin, Adolpho H. Augustin, Vinicius N. Moreira, et al. "Origin and Alteration of Organic Matter in Hydrate-Bearing Sediments of the Rio Grande Cone, Brazil: Evidence from Biological, Physical, and Chemical Factors." Radiocarbon 62, no. 1 (September 2, 2019): 197–206. http://dx.doi.org/10.1017/rdc.2019.109.

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ABSTRACTThe Rio Grande Cone is a major fanlike depositional feature in the continental slope of the Pelotas Basin, Southern Brazil. Two representative sediment cores collected in the Cone area were retrieved using a piston core device. In this work, the organic matter (OM) in the sediments was characterized for a continental vs. marine origin using chemical proxies to help constrain the origin of gas in hydrates. The main contribution of OM was from marine organic carbon based on the stable carbon isotope (δ13C-org) and total organic carbon/total nitrogen ratio (TOC:TN) analyses. In addition, the 14C data showed important information about the origin of the OM and we suggest some factors that could modify the original organic matter and therefore mask the “real” 14C ages: (1) biological activity that could modify the carbon isotopic composition of bulk terrestrial organic matter values, (2) the existence of younger sediments from mass wasting deposits unconformably overlying older sediments, and (3) the deep-sediment-sourced methane contribution due to the input of “old” (>50 ka) organic compounds from migrating fluids.

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Vlachos, Marinos, and Dimitrios Skarlatos. "An Extensive Literature Review on Underwater Image Colour Correction." Sensors 21, no. 17 (August 24, 2021): 5690. http://dx.doi.org/10.3390/s21175690.

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The topic of underwater (UW) image colour correction and restoration has gained significant scientific interest in the last couple of decades. There are a vast number of disciplines, from marine biology to archaeology, that can and need to utilise the true information of the UW environment. Based on that, a significant number of scientists have contributed to the topic of UW image colour correction and restoration. In this paper, we try to make an unbiased and extensive review of some of the most significant contributions from the last 15 years. After considering the optical properties of water, as well as light propagation and haze that is caused by it, the focus is on the different methods that exist in the literature. The criteria for which most of them were designed, as well as the quality evaluation used to measure their effectiveness, are underlined.

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Bard, Edouard, Guillemette Ménot, Frauke Rostek, Laetitia Licari, Philipp Böning, R. Lawrence Edwards, Hai Cheng, Yongjin Wang, and Timothy J. Heaton. "Radiocarbon Calibration/Comparison Records Based on Marine Sediments from the Pakistan and Iberian Margins." Radiocarbon 55, no. 4 (2013): 1999–2019. http://dx.doi.org/10.2458/azu_js_rc.55.17114.

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We present a new record of radiocarbon ages measured by accelerator mass spectrometry (AMS) on a deep-sea core collected off the Pakistan Margin. The 14C ages measured on the planktonic foraminifera Globigerinoides ruber from core MD04-2876 define a high and stable sedimentation rate on the order of 50 cm/kyr over the last 50 kyr. The site is distant from the main upwelling zone of the western Arabian Sea where 14C reservoir age is large and may be variable. Many independent proxies based on elemental analyses, mineralogy, biomarkers, isotopic proxies, and foraminiferal abundances show abrupt changes correlative with Dansgaard-Oeschger and Heinrich events. It is now common knowledge that these climatic events also affected the Arabian Sea during the last glacial period through changes in the Indian monsoon and in ventilation at intermediate depths. The stratigraphic agreement between all proxies, from fine- to coarse-size fractions, indicates that the foraminiferal 14C ages are representative of the different sediment fractions.To build a calendar age scale for core MD04-2876, we matched its climate record to the oxygen isotopic (δ18O) profile of Hulu Cave stalagmites that have been accurately dated by U-Th (Wang et al. 2001; Southon et al. 2012; Edwards et al., submitted). Both archives exhibit very similar signatures, even for century-long events linked to monsoonal variations. For comparison, we have also updated our previous work on core MD95-2042 from the Iberian Margin (Bard et al. 2004a,b,c), whose climate record has likewise been tuned to the high-resolution δ18O Hulu Cave profile. Sophisticated and novel statistical techniques were used to interpolate ages and calculate uncertainties between chronological tie-points (Heaton et al. 2013, this issue). The data from the Pakistan and Iberian margins compare well even if they come from distant sites characterized by different oceanic conditions. Collectively, the data also compare well with the IntCal09 curve, except for specific intervals around 16 cal kyr BP and from 28 to 31 cal kyr BP. During these intervals, the data indicate that 14C is somewhat older than indicated by the IntCal09 curve. Agreement between the data from both oceanic sites suggests that the discrepancy is not due to local changes of sea-surface 14C reservoir ages, but rather that the IntCal09 curve needed to be updated in these intervals as has been done in the framework of IntCal13 (Reimer et al. 2013a, this issue).

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Choi, J. H., A. S. Murray, C. S. Cheong, D. G. Hong, and H. W. Chang. "The resolution of stratigraphic inconsistency in the luminescence ages of marine terrace sediments from Korea." Quaternary Science Reviews 22, no. 10-13 (May 2003): 1201–6. http://dx.doi.org/10.1016/s0277-3791(03)00022-2.

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Podgorny, K. A., and A. V. Leonov. "CALCULATION OF PARAMETER VALUES TO CHARACTERIZE THE CONSEQUENCES OF WORK ON THE DREDGING AND SUSPENDED MATTER DAMPING: ASSESSMENT BY MEANS OF THE SM-MODEL." Journal of Oceanological Research 48, no. 2 (August 28, 2020): 107–34. http://dx.doi.org/10.29006/1564-2291.jor-2020.48(2).7.

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The developed SM-model, describing the suspended matter concentrations in water environment, was used to assess the consequences of the works on dredging and dumping ground during the reconstruction and modernization of the water body area in the Pionersky Port (Kaliningrad region). The complex of recreated works includes 11 stages of the dredging works during which the various types of bottom sediments are extracted, some part of these sediments are transported outside the port water area and discharged into the marine underwater dump, while other their part are used for hydraulic engineering works in the port area. At the dredging and dumping the sediments, additional zones of water turbidity are formed (with a suspended matter concentration > 50 mg/L), its deposition causes the formation of a layer of sediments on the bottom. For each work stages, the technological data on the currents in the port water area are used for mathematical modeling and calculations of the amounts of various types of sediments extracted from the bottom, their redistribution over the sea area, the concentration of suspended matter in sea water, and the indicators (areas and volumes) of the emerging turbidity zones water due as a result of the construction works. Calculated data may be used to compile a report “Assessment of influence on the water environment state” (or AIWES) in the frame of these works.

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Sveinbjörnsdóttir, Árný E., Jan Heinemeier, Peter Kristensen, Niels Rud, Áslaug Geirsdóttir, and Jórunn Harđardóttir. "14C AMS Dating of Icelandic Lake Sediments." Radiocarbon 40, no. 2 (1997): 865–72. http://dx.doi.org/10.1017/s003382220001883x.

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We report an age-depth profile for the sediments of the Lake Hesrvatn, southern Iceland, based on 14C analyses of the organic fraction of bulk sediment samples, molluscs and foraminifera. Our age-depth curve is supported by the occurrence of the well-dated Vedde ash in the lowermost part of the sediments. Comparison of foraminifera dates with the age of the Vedde ash indicates a reservoir age of ca. 400 yr. The results suggest that the sediments at Hestvatn accumulated in a marine environment until ca. 8700 bp and thereafter in freshwater.Owing to the lack of terrestrial macrofossils and the low concentration of molluscs and foraminifera, we were forced to attempt to date most of the core with the organic fraction of the bulk sediment samples. We found, however, that this fraction is not homogeneous in density or 14C age. We believe that during sample pretreatment we managed to isolate a light organic fraction, which closely represents the true age of the sediment, whereas the denser fraction yields ages that are too high. This age diversity may to some extent be explained by the large drainage area of the lake, from which plant remains of different ages may have been washed into the lake.

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Nakanishi, Toshimichi, Tomohiro Tsuji, Futoshi Nanayama, Tatsuhiko Yamaguchi, Yasuo Kondo, Michiharu Ikeda, and Wan Hong. "Radiocarbon age offsets of Plants and Shells in Holocene sediments from the Sukumo plain, Southwest Coast of Shikoku, Southwest Japan." Radiocarbon 61, no. 6 (November 5, 2019): 1951–61. http://dx.doi.org/10.1017/rdc.2019.129.

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AbstractTo identify chronological changes in the marine reservoir effect in southwest Japan, the radiocarbon ages of eight pairs of marine shells and terrestrial plants were measured from the same horizons of one core of Holocene sediments. This core was obtained from the northern part of the Sukumo Plain in southwestern Shikoku Island, which faces the warm Kuroshio Current. The drilling site is located in an area of subsidence associated with the convergence of the Philippine Sea Plate and the Eurasian Plate. On analyses of lithology, molluscan assemblages, and radiocarbon dating, we interpreted, from oldest to youngest, nine units: basement rock, a braided river channel, a meandering river channel, an estuary, a transgressive inner bay, Kikai-Akahoya volcanic ash, a deltaic inner bay, a tidal flat, and artificial soil. Changes in the depositional environment were mainly associated with sea-level rise after the end of the last glaciation. The reservoir ages of the eight pairs, 330 ± 70 yr, were obtained from a transgressive inner bay to deltaic inner bay sediments, formed during 4100–9200 cal BP. The chronological change in the reservoir effect allows us to correlate the Sukumo Core sediments with previous results from southwestern Japan, the Korean Peninsula, and Taiwan Island.

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Ridwan, Nia Hasanah. "MARITIME ARCHAEOLOGY IN INDONESIA: RESOURCES, THREATS, AND CURRENT INTEGRATED RESEARCH." Journal of Indo-Pacific Archaeology 36 (November 22, 2016): 16. http://dx.doi.org/10.7152/jipa.v36i0.14911.

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With a sea area covering two thirds of the country, 95,181 km of coastline, and its location at a crossroads of international seafaring and trading routes, Indonesia has developed over time a wealthy maritime and underwater cultural heritage (UCH) in the form of shipwrecks, aircraft wreckages, and other maritime sites. This paper will present the potential of maritime archaeology in Indonesia; current issues and legislations in researching, preserving and managing UCH sites; and present the various threats assessed through a number of studies conducted by the Ministry of MarineAffairs and Fisheries. It will also looks at approaches in implementing integrated and comprehensive maritime archeologyresearch involving a wide range of relevant expertise to meet the challenges of research in identifying and responding to the threats, both natural and human, faced today byUCH sites. Nowadays, maritime archaeological research in Indonesia is oriented toward marine heritage tourism. The denomination of sites as marine conservation areas protected by national legislation is an integral part of maritime archaeological research and a crucial strategy of the Ministry in the hope that these sites be used as a tool for poverty alleviation and the improvement of the local community's livelihood.

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KJEMPERUD, ALFRED. "Diatom changes in sediments of basins possessing marine/lacustrine transitions in Frosta, Nord-Trøndelag, Norway." Boreas 10, no. 1 (January 16, 2008): 27–38. http://dx.doi.org/10.1111/j.1502-3885.1981.tb00466.x.

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Diamanti, E., E. Spondylis, F. Vlachaki, and E. Kolyva. "SURVEYING THE UNDERWATER ARCAHEOLOGICAL SITE OF CAPE GLAROS AT PAGASETIKOS GULF." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W3 (February 23, 2017): 243–50. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w3-243-2017.

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The Hellenic Institute of Marine Archaeology (H.I.M.A.)1 has been conducting an underwater archaeological research in the west coast of southern Pagasetikos Gulf, since 2000. Every year the underwater research focuses on specific archaeological targets that have been recovered during previous field campaigns. The current publication elaborates on the comprehensive documentation of the underwater archaeological site at Cape Glaros, during the 2015 field season, under the direction of the archaeologist Elias Spondylis. The 2015 research campaign was conducted within the framework of the ITACA- Innovation Technologies and Applications for Coastal Archaeological sites European Project (FP7/2007-2013, GA No 606805), at two archaeological sites, namely the Cape Glaros and Metohi. It was among the most important challenges of the project to successfully produce the detailed and accurate 3D mapping of the Cape Glaros site that covers an extended area. Four large concentrations of pottery finds and numerous anchors of different typology have been recorded, that can be dated from the late Hellenistic to the Byzantine periods. This challenge was tackled through the simultaneous implementation of three recording methods; photogrammetry, geodesy and conventional architectural mapping. The workflow of the documentation process, including data acquisition, processing and graphic visualization, along with the derived results are presented below. 1The Hellenic Institute of Marine Archaeology (H.I.M.A.) is a private, non-profit organization, founded in 1973, which undertakes maritime archaeological research under the supervision or in collaboration with the Greek Ministry of Culture. It has over 100 members, with diverse academic credentials, all of whom work, mainly, on a voluntary basis. 3D recording of underwater archaeological sites has been applied to numerous projects that have been carried out by the multidisciplinary team of H.I.M.A. in locations of utmost archaeological importance and interest, such as Modi island (Poros) and numerous wreck sites in Pagasetikos and South Euboean (Diamanti, Vlachaki, 2015) Gulfs and others.

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Bao, Rui, Ann P. McNichol, Cameron P. McIntyre, Li Xu, and Timothy I. Eglinton. "Dimensions of Radiocarbon Variability within Sedimentary Organic Matter." Radiocarbon 60, no. 3 (May 30, 2018): 775–90. http://dx.doi.org/10.1017/rdc.2018.22.

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ABSTRACTOrganic carbon (OC) radiocarbon (14C) signatures in marine surface sediments are highly variable and the causes of this heterogeneity remain ambiguous. Here, we present results from a detailed 14C-based investigation of an Arabian Sea sediment, including measurements on organic matter (OM) in bulk sediment, specific grain size fractions, and OC decomposition products from ramped-pyrolysis-oxidation (RPO). Our results show that 14C ages of OM increase with increasing grain size, suggesting that grain size is an important factor controlling the 14C heterogeneity in marine sediments. Analysis of RPO decomposition products from different grain size fractions reveals an overall increase in age of corresponding thermal fractions from finer to coarser fractions. We suggest that hydrodynamic properties of sediment grains exert the important control on the 14C age distribution of OM among grain size fractions. We propose a conceptual model to account for this dimensionality in 14C variability that invokes two predominant modes of OM preservation within different grain size fractions of Arabian Sea sediment: finer (<63 µm) fractions are influenced by OM-mineral grain aggregation processes, giving rise to relatively uniform 14C ages, whereas OM preserved in coarser (>63 µm) fractions includes materials encapsulated within microfossils and/or entrained fossil (14C-depleted) OC hosted in detrital mineral grains. Our findings highlight the value of RPO for assessment of 14C age variability in sedimentary OC, and for assessing mechanisms of OM preservation in aquatic sediments.

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Phillips, Emrys, and Jon Merritt. "Evidence for multiphase water-escape during rafting of shelly marine sediments at Clava, Inverness-shire, NE Scotland." Quaternary Science Reviews 27, no. 9-10 (May 2008): 988–1011. http://dx.doi.org/10.1016/j.quascirev.2008.01.012.

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Diamanti, Eleni, Andreas Georgopoulos, and Fotini Vlachaki. "Geometric documentation of underwater archaeological sites." Geoinformatics FCE CTU 11 (December 28, 2013): 37–48. http://dx.doi.org/10.14311/gi.11.3.

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Photogrammetry has often been the most preferable method for the geometric documentation of monuments, especially in cases of highly complex objects, of high accuracy and quality requirements and, of course, budget, time or accessibility limitations. Such limitations, requirements and complexities are undoubtedly features of the highly challenging task of surveying an underwater archaeological site. This paper is focused on the case of a Hellenistic shipwreck found in Greece at the Southern Euboean gulf, 40-47 meters below the sea surface. Underwater photogrammetry was chosen as the ideal solution for the detailed and accurate mapping of a shipwreck located in an environment with limited accessibility. There are time limitations when diving at these depths so it is essential that the data collection time is kept as short as possible. This makes custom surveying techniques rather impossible to apply. However, with the growing use of consumer cameras and photogrammetric software, this application is becoming easier, thus benefiting a wide variety of underwater sites. Utilizing cameras for underwater photogrammetry though, poses some crucial modeling problems, due to the refraction effect and further additional parameters which have to be co-estimated [1]. The applied method involved an underwater calibration of the camera as well as conventional field survey measurements in order to establish a reference frame. The application of a three-dimensional trilateration using common tape measures was chosen for this reason. Among the software that was used for surveying and photogrammetry processing, were Site Recorder SE, Eos Systems Photomodeler, ZI’s SSK and Rhinoceros. The underwater archaeological research at the Southern Euboean gulf is a continuing project carried out by the Hellenic Institute for Marine Archaeology (H.I.M.A.) in collaboration with the Greek Ephorate of Underwater Antiquities, under the direction of the archaeologist G.Koutsouflakis. The geometric documentation of the shipwreck was the result of the collaboration between H.I.M.A. and the National Technical University of Athens.

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Diamanti, E., and F. Vlachaki. "3D RECORDING OF UNDERWATER ANTIQUITIES IN THE SOUTH EUBOEAN GULF." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-5/W5 (April 9, 2015): 93–98. http://dx.doi.org/10.5194/isprsarchives-xl-5-w5-93-2015.

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An underwater archaeological survey was initiated in 2006 by the Hellenic Institute of Marine Archaeology in collaboration with the Ephorate of Underwater Antiquities of Greece, in the South Euboean Gulf. The survey is being conducted under the direction of the archaeologist Dr G. Koutsouflakis and in the course of the project important shipwrecks of Classical, Roman, and Byzantine periods have been brought to light, adding tangible evidence on ancient seafaring and maritime trade. The South Euboean Gulf archaeological survey has presented many challenges to the documentation team of H.I.M.A, and has served as a case-study for 3D recording applied on ancient wrecks, found at medium depths (22-47m) and under the conditions that are imposed during an archaeological survey of a certain geographical region. This paper focuses on the implementation of photogrammetric and geodetic techniques used for acquisition and processing of collected data, in order to generate 3D models for six different wrecks, resulting in a fast, reliable and cost efficient method to record underwater archaeological sites.

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Fanelli, Francesco, Niccolò Monni, Nicola Palma, and Alessandro Ridolfi. "Development of an ultra short baseline–aided buoy for underwater targets localization." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 233, no. 4 (February 1, 2019): 1212–25. http://dx.doi.org/10.1177/1475090219825768.

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Autonomous underwater vehicles localization and navigation are challenging due to the lack of Global Positioning System underwater: alternative techniques have then to be used in order to measure the position of the vehicle. To this aim, sensor fusion methods based on acoustic positioning systems are often exploited. This article faces the study and the improvement of the localization of an underwater target through an ultra short baseline–aided buoy built by the Mechatronics and Dynamic Modelling Laboratory of the University of Florence. Such a buoy relies on an ultra short baseline device for the localization and is aided by a proper sensor set in order to compensate variations in its pose. First, a study of the underwater localization based on the ultra short baseline technique is provided. The measurement errors entailed by the buoy motion are then analyzed and preliminarily compensated, exploiting linear least squares methods. Subsequently, filtering techniques are considered with the aim to further increase the accuracy of the ultra short baseline measurements. Due to the nonlinearities of the sensors characteristics, extended Kalman filter has been used, with different models for stationary and moving targets. The solutions proposed have been validated through experimental tests conducted with MArine Robotic Tool for Archaeology autonomous underwater vehicles built by the Mechatronics and Dynamic Modelling Laboratory. The results evidence an improved vehicle localization, suggesting interesting future developments concerning both mechanical and computational solutions.

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Bao, Rui, Ann P. McNichol, Jordon D. Hemingway, Mary C. Lardie Gaylord, and Timothy I. Eglinton. "Influence of Different Acid Treatments on the Radiocarbon Content Spectrum of Sedimentary Organic Matter Determined by RPO/Accelerator Mass Spectrometry." Radiocarbon 61, no. 2 (November 13, 2018): 395–413. http://dx.doi.org/10.1017/rdc.2018.125.

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ABSTRACTIn practice, obtaining radiocarbon (14C) composition of organic matter (OM) in sediments requires first removing inorganic carbon (IC) by acid-treatment. Two common treatments are acid rinsing and fumigation. Resulting14C content obtained by different methods can differ, but underlying causes of these differences remain elusive. To assess the influence of different acid-treatments on14C content of sedimentary OM, we examine the variability in14C content for a range of marine and river sediments. By comparing results for unacidified and acidified sediments [HCl rinsing (RinseHCl) and HCl fumigation (FumeHCl)], we demonstrate that the two acid-treatments can affect14C content differentially. Our findings suggest that, for low-carbonate samples, RinseHClaffects the Fm values due to loss of young labile organic carbon (OC). FumeHClmakes the Fm values for labile OC decrease, leaving the residual OC older. High-carbonate samples can lose relatively old organic components during RinseHCl, causing the Fm values of remaining OC to increase. FumeHClcan remove thermally labile, usually young, OC and reduce the Fm values. We suggest three factors should be taken into account when using acid to remove carbonate from sediments: IC abundance, proportions of labile and refractory OC, and environmental matrix.

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Journal articles on the topic 'Marine sediments Underwater archaeology'

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