Fieldwork at EI Merj (Ancient Barca): A First Report on the 1992 Season

1993 ◽  
Vol 24 ◽  
pp. 117-120 ◽  
Author(s):  
J. N. Dore ◽  
J. S. Rowan ◽  
J. P. Davison
Keyword(s):  
Contextual Information ◽  
Central Area ◽  
Coarse Grained ◽  
Silty Clay ◽  
Flood Events ◽  
Terra Rossa ◽  
Archaeological Evidence ◽  
Depositional History ◽  
High Magnitude ◽  
Clay Sediment

AbstractThe principal aim of this season's investigations was to obtain contextual information on the geological, geo-morphological and hydrological processes operating within the environs of El Merj, to complement existing archaeological evidence. Provisional conclusions show that broad similarities exist between profiles obtained at two points on the site suggesting that the central area of the site has undergone a similar depositional history. The site seems to have been subject to regular inundation by flood events, occurring 1–2 times per year, which deposited significant quantities of silty-clay sediment eroded from terra rossa soils of the Jebel Akhdar. Less frequently, coarse-grained gravel and cobble deposits were introduced to the profiles, indicative of the effects of much rarer high magnitude floods.

scholarly journals Contextualized Filtering for Shared Cyber Threat Information

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4890
Author(s):  
Athanasios Dimitriadis ◽  
Christos Prassas ◽  
Jose Luis Flores ◽  
Boonserm Kulvatunyou ◽  
Nenad Ivezic ◽  
...  
Keyword(s):  
Information Sharing ◽  
Business Processes ◽  
State Of The Art ◽  
Contextual Information ◽  
Coarse Grained ◽  
Business Information ◽  
Cyber Threat ◽  
Domain Expertise ◽  
Multi Level ◽  
Filtering Approach

Cyber threat information sharing is an imperative process towards achieving collaborative security, but it poses several challenges. One crucial challenge is the plethora of shared threat information. Therefore, there is a need to advance filtering of such information. While the state-of-the-art in filtering relies primarily on keyword- and domain-based searching, these approaches require sizable human involvement and rarely available domain expertise. Recent research revealed the need for harvesting of business information to fill the gap in filtering, albeit it resulted in providing coarse-grained filtering based on the utilization of such information. This paper presents a novel contextualized filtering approach that exploits standardized and multi-level contextual information of business processes. The contextual information describes the conditions under which a given threat information is actionable from an organization perspective. Therefore, it can automate filtering by measuring the equivalence between the context of the shared threat information and the context of the consuming organization. The paper directly contributes to filtering challenge and indirectly to automated customized threat information sharing. Moreover, the paper proposes the architecture of a cyber threat information sharing ecosystem that operates according to the proposed filtering approach and defines the characteristics that are advantageous to filtering approaches. Implementation of the proposed approach can support compliance with the Special Publication 800-150 of the National Institute of Standards and Technology.

scholarly journals Recycling and Reuse of Sediments in Agriculture: Where Is the Problem?

2021 ◽  
Vol 13 (4) ◽  
pp. 1648
Author(s):  
Giancarlo Renella
Keyword(s):  
Scientific Evidence ◽  
Significant Proportion ◽  
Silty Clay ◽  
Fine Sediments ◽  
Sediment Fraction ◽  
Biodegradation Process ◽  
Component Material ◽  
Long Time ◽  
Clay Sediment ◽  
International Conventions

Though suggested by international conventions for a long time, there are still several technical and legislative limitations to a complete reuse and recycling of dredged sediments. In particular, reuse of unpolluted sediments can be practiced, whereas sediment recycling is still affected by several downsides, and a significant proportion of the recycled fine sediments has no practical use and must be landfilled. However, the silty clayey fraction of the recycled sediments is rich in organic matter and macro- and micronutrients useful for plant growth. Nevertheless, sediment recycling in agriculture is not possible, even in non-food agricultural sectors, due to the lack of a permissive legislation and of consolidated supply chains. In addition to plant nutrients, the silty-clay sediment fraction may also accumulate organic and inorganic pollutants, and while the organic pollutants can be effectively biodegraded, metals and metalloids may concentrate at concentrations higher than the limits set by the environmental and agricultural legislations. In this paper, I briefly summarize the scientific evidence on the potential reuse and recycling of sediments in agriculture, and I discuss the main reasons for hindrance of sediment recycling in agriculture. I also present evidence from a real industrial biodegradation process that produces bioremediated fine sediment fractions with suitable properties as a mineral ingredient for plant-growing media. I propose that nutrient-rich recycled sediments could be reconsidered as a component material category in the new EU regulation on fertilizers.

scholarly journals The geochemistry of the northern part of the Ilímaussaq intrusion, S.W. Greenland

1964 ◽  
Vol 42 ◽  
pp. 1-104
Author(s):  
E.I Hamilton
Keyword(s):  
Central Area ◽  
Confining Pressure ◽  
Coarse Grained ◽  
Residual Liquid ◽  
Relative Time ◽  
Central Mass ◽  
Basement Rocks ◽  
Field Evidence ◽  
Show Evidence ◽  
High Level

The Ilímaussaq intrusion (S.W. Greenland) was emplaced into granitic Precambrian basement rocks. The intrusion is of a highly alkaline nature and in terms of rocks types, its major-, minor- and trace elements, may be compared to the Khibina-Lovozero intrusion of the Kola Peninsula, U.S.S.R. The present paper describes the geochemistry of the northern part of the intrusion and the marginal rocks. New total rock analyses are given together with the detailed geochemistry of U, Th, Radioactivity, Nb, Rb, Li and Be. The Ilímaussaq intrusion consists of an early augite syenite chilled against the country rocks. The augite syenite forms a more or less continuous ring around and above the intrusion. The main central mass of the intrusion consists of poorly layered, very coarse-grained, Na-rich "foyaite" containing relatively large amounts of sodalite and eudialyte. Differentiation of the "foyaite magma" gave rise to a volatile rich residual liquid from which lujavrites were formed. Differentiation of the lujavrites in the central area of the intrusion resulted in a lower banded sequence, the kakortokites, and an upper lujavrite liquid. When the confining pressure was exceeded, explosive brecciation occurred and lujavrite was intruded into the surrounding rocks. At a high level in the intrusion a sheet-like body of soda granite was emplaced together with various quart-bearing syenites. The relative time of intrusion of the quartz-bearing syenite is uncertain through lack of field evidence. Emplacement of the early augite syenite may be related to ring faulting followed by cauldron subsidence. The later Na-rich rocks may have replaced the earlier layered augite syenite or have been emplaced into a "magma chamber" developed by cauldron subsidence. The Na-Zr-Cl-rich rocks show evidence of cooling inwards with the development of a central volatile-rich pocket. The Ilímaussaq rocks probably represent a final highly fractionated stage of the more normal augite syenite magma common to the S. W. Greenland alkaline province.

Experimental Study of Silty Clay's Deformation Fields Based on the Principles of Oedometer Tests

2011 ◽  
Vol 261-263 ◽  
pp. 1539-1543
Author(s):  
Wen Bai Liu ◽  
Liang Cao ◽  
Xiao Zhao Li ◽  
Ye Xun Li ◽  
Peng Wang
Keyword(s):  
Experimental Study ◽  
Image Analysis ◽  
Digital Image Analysis ◽  
Central Area ◽  
Measurement Technology ◽  
Silty Clay ◽  
New Apparatus ◽  
Chinese Patent ◽  
Oedometer Tests ◽  
Increasing Load

Based on the principles of conventional oedometer tests, half mold consolidation apparatus which attained Chinese Patent Certificate of New and Practical Device was designed for non-saturated soil's micro-observation with axial drainage conditions. By half mold consolidation tests, we could get similar stress-strain curves at different water content, which could illustrate the feasibility of the new apparatus. Besides, on the application of DPDM (the digital photogrammetry for deformation measurement) technology, the deformation fields of the silty clay were analyzed under monotonic increasing load, which could obviously show the macro mechanics properties by digital image analysis. According to the distribution of deformation fields, the analyzing area could be divided into three parts from top to bottom sequence: soil in top area subsided with upper porous-stone in balance; the deformation in the central area was changing the most whereas there had always been inapparent changes near down porous-stone. Such study could put forward a new conception for the development of conventional soil tests, which could be helpful to further establish the theoretical constitutive model for silty clay.

scholarly journals The geometry and stratigraphic position of the Maassluis Formation (western Netherlands and southeastern North Sea)

2004 ◽  
Vol 83 (2) ◽  
pp. 93-99 ◽  
Author(s):  
H.S.M. Jansen ◽  
J. Huizer ◽  
J.W.A. Dijkmans ◽  
C. Mesdag ◽  
J.E. van Hinte
Keyword(s):  
Coarse Grained ◽  
Early Pleistocene ◽  
The West ◽  
Depositional History ◽  
Offshore Area ◽  
Coastal Marine ◽  
Subtidal Environment ◽  
Stratigraphic Position ◽  
History Of ◽  
River Deposits

AbstractThe geometry and depositional history of the Maassluis Formation is described from an East-West oriented transect located in the west-central Netherlands and P- and Q-blocks in the Dutch offshore area. The Late Pliocene to Early Pleistocene Maassluis Formation was deposited under near coastal marine conditions. Two distinct facies are distinguished: (1) medium grained sands with a blocky GR/SP-log pattern that were deposited under intertidal and aeolian conditions and (2) medium to coarse grained sands deposited in a subtidal environment showing a clear coarsening upward trend. The lower part of the Maassluis Formation is laterally equivalent to the shallow marine Oosterhout Formation and gets progressively younger towards the West. The upper part is lateral equivalent to estuarine and mudflat deposits (Balk Member, c.q. Peize Formation) in the central part of The Netherlands and to river deposits (Peize Formation) further to the East.

scholarly journals Improving the quantitative estimation of trawling impacts from sidescan-sonar and underwater-video imagery

2007 ◽  
Vol 64 (9) ◽  
pp. 1692-1701 ◽  
Author(s):  
C. J. Smith ◽  
A. C. Banks ◽  
K-N. Papadopoulou
Keyword(s):  
Quantitative Estimation ◽  
Rapid Assessment ◽  
The Other ◽  
Sidescan Sonar ◽  
Silty Clay ◽  
Underwater Video ◽  
Data Usage ◽  
Video Imagery ◽  
Assessment Techniques ◽  
Clay Sediment

Abstract Smith, C. J., Banks, A. C., and Papadopoulou, K.-N. 2007. Improving the quantitative estimation of trawling impacts from sidescan-sonar and underwater-video imagery. – ICES Journal of Marine Science, 64: 1692–1701. The techniques of sidescan sonar and towed, underwater-video sled were assessed as rapid-assessment methodologies for investigating trawl impacts on the substratum. Sidescan sonar is able to image a swathe of ∼200 m with a resolution of ∼20 cm at a speed of 2–3 knots, and marks of trawl doors could be observed. The towed video system imaged a swathe of 1–2 m with a resolution of 1–2 cm at a speed of ∼1 knot, and trawl-door marks, scrape marks, local bioturbation features, and fauna could be observed. Multiple tows using both methodologies were carried out in two areas in Heraklion Bay, Crete. One area, experimentally trawled, was 80–90 m deep and characterized by mixed, maerly sediments; the other was a commercial trawl lane ∼200 m deep characterized by silty-clay sediment. Descriptions of the types of trawling feature and impacts caused by trawling were made for both areas. Images were analysed from the commercial deeper trawling ground for area assessment. For sidescan-sonar records, direction of trawling and trawl-mark density by category were estimated at periodic intervals along the track. For video, categories for trawl-mark density and level of bioturbation were estimated, along with the density of the crinoid Leptometra phalangium. Using geo-referenced positioning for each data point, area maps were constructed for each of the parameters, and correlations were tested between the different datasets. The use of the assessment techniques (characteristics, data usage, mapping, complementarity) in relation to trawling-impact studies is discussed, as well as possibilities for the use of the resulting data for management.

scholarly journals The role of precipitation for high-magnitude flood generation in a large mountainous catchment (upper Rhône River, NW European Alps)

2019 ◽  
Author(s):  
Florian Raymond ◽  
Bruno Wilhelm ◽  
Sandrine Anquetin
Keyword(s):  
Heavy Precipitation ◽  
European Alps ◽  
Flood Events ◽  
Rhône River ◽  
High Magnitude ◽  
Extreme Flood ◽  
Rhone River ◽  
Flood Generation ◽  
Rain Floods

Abstract. High-impact climate events such as floods are highly destructive natural hazards causing widespread impacts on socio-ecosystems. However, processes leading to such events are still poorly understood, which limiting reliable prediction. This study takes advantage of centennial-long discharge series (1923–2010) and meteorological reanalysis (ERA-20C) to study processes generating the high-magnitude flood events (i.e. above the percentile 99.9) of the upper Rhône River (NW European Alps). A particular focus is paid to the role of precipitation on the flood generation to explore in what extent such events could be explained by only atmospheric variables. A flood typology is thus established using a hierarchical clustering analysis and three variables: long (8-day) and short (2-day) precipitation accumulations as well as an index characterizing the amplitude of the discharge increase during the 7 days prior to the flood day. The typology result in four classes, of which two are directly linked to precipitation. One results from heavy precipitation over two days (similar to short-rain floods in the literature) and the other one from a combination of short and long intense precipitation sequences (similar to long-rain floods). The two other types of floods cannot be explained by precipitation only, most probably involving ice and snow melting. The four events of highest magnitude (> 20 year return period) are of various types but are all triggered by heavy precipitation during the days preceding the floods. The role of the precipitation accumulations progressively decreases when considering floods of weaker magnitude, suggesting a higher diversity of processes involved in the generation of e.g. annual flooding. Our results highlight the needs to better understand the atmospheric processes leading to heavy precipitation accumulation since this would allow a better understanding of past and future trends of extreme flood events.

Lacustrine record of high magnitude flood events and climate variability during mid to late Holocene in the semiarid alluvial plains, western India

2020 ◽  
Vol 542 ◽  
pp. 109581 ◽  
Author(s):  
Alpa Sridhar ◽  
Biswajeet Thakur ◽  
Nathani Basavaiah ◽  
Priyanka Seth ◽  
Pooja Tiwari ◽  
...  
Keyword(s):  
Climate Variability ◽  
Late Holocene ◽  
Western India ◽  
Flood Events ◽  
High Magnitude

Hydrologic and Geomorphic Aspects of High-magnitude Floods on the Par River in Western India

2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Archana Patil ◽  
Priyanka Hire ◽  
Pramodkumar Hire
Keyword(s):  
Reynolds Number ◽  
Shear Stress ◽  
Critical Velocity ◽  
Western India ◽  
Flood Events ◽  
Stream Power ◽  
Boundary Shear ◽  
High Magnitude ◽  
Geomorphic Features ◽  
Boundary Shear Stress

The geomorphic effectiveness of floods is evaluated in terms of unit stream power (ω) and boundary shear stress (τ) for floods on the Par River. The highest values for ω and τ for a flood on the river are 52125 W/m2 and 3320 N/m2, respectively. The estimated Froude numbers are <1 indicating subcritical flows. It is >1 for a few constricted reaches showing supercritical or shooting flows. High values of Reynolds number reveal that the flood discharges were extremely turbulent. Values of critical velocity for the inception of cavitation (Vc) show that none of the powerful floods on the river, except two, exceed the conditions. Estimates of ω, τ and velocity associated with transported boulders indicate that all floods were competent to move large boulders of more than 5.5 m in diameter. The efficiency of high-magnitude flood events is evident from the presence of a variety of geomorphic features.

Evolution of Tidal Flats in the Northern Part of the Po Delta (Italy):  A Strategy for Future Buiding-with-Nature Management

2021 ◽  
Author(s):  
Riccardo Brunetta ◽  
Paolo Ciavola
Keyword(s):  
Tidal Flat ◽  
Central Area ◽  
Tidal Flats ◽  
Silty Sand ◽  
Nature Management ◽  
Silty Clay ◽  
Po River ◽  
Sediment Distribution ◽  
Clayey Silt ◽  
River Floods

&lt;p&gt;In the period 1950s-60s, the Po river Delta (Northern Italy) was hit by several floods. Agricultural fields were covered by water and many of them remained submerged since. As a consequence of the massive sediment injection into the system, this lead to the birth of new tidal flats around the tip of the Delta. The evolution of these environments over 50 years was studied, as they may be taken as an example for future reconstruction of intertidal areas. The sediment distribution and the morphological evolution of a young tidal flat of about 10 ha located in the Northern part of the Po della Pila branch were studied by undertaking fieldwork since October 2018, including detailed topographic surveys using a UAV, sedimentological analyses, and a study of sediment deposition rates. An extended crevasse splay covers the central part of the flat. The granulometry is predominately fine (Silty clay and Clayey silt), except for the central area, where the sand percentage increases (Loam and Silty sand). This surface distribution is uniform down to ~10 cm; the sand percentage increases instead within the sediment column from ~10 to 25 cm next to the mouths of the channels. The tidal flat experienced a positive sediment budget and it was characterized by higher rates of accretion after the Po river floods. These observations suggest that the tidal channels are fed by sediment from the Po River branch. Orthophotos from the 1950s show that the tidal flat is about 17 - 20 years old and its formation was influenced by human intervention and river floods. The work aims at finally comparing this case study with other tidal flats and salt marshes worldwide characterized by similar and different tidal regimes, to identify the optimal elevation for vegetation to establish and flourish, to support the future restoration of these environments.&lt;/p&gt;

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