Suspended Sand Transport on a Dissipative Beach

1985 ◽  
Author(s):  
John P. Downing
Keyword(s):  
Sand Transport

COASTAL ALTERATION AND CHANGES IN SHORELINE MORPHOLOGY DUE TO ARTIFICIAL STRUCTURES IN MIIRAKU TOWN ON FUKUE IS. IN THE GOTO ARCHIPELAGO

2017 ◽  
Author(s):  
Ryo Sakamoto ◽  
Ryo Sakamoto ◽  
Satoquo Seino ◽  
Satoquo Seino ◽  
Hirokazu Suzaki ◽  
...  
Keyword(s):  
Tang Dynasty ◽  
National Park ◽  
Survey Methods ◽  
Aerial Photographs ◽  
Sand Transport ◽  
The Status ◽  
The Tang Dynasty ◽  
Coastal Changes ◽  
Century Poetry ◽  
Nagasaki Prefecture

A construction of breakwaters and other shoreline structures on part of a coast influences drift sand transport in the bay, and causes comprehensive topographic changes on the beach. This study investigated shoreline and coastal changes, taking as an example of Shiraragahama Beach in Miiraku on the northwestern end of Fukue Island, Nagasaki Prefecture (Kyushu, Japan). Miiraku, adjacent to Saikai National Park, appears in the revered 8th century poetry collection “Manyoshu” and served as a port for a ship taken by the Japanese envoy to China during the Tang Dynasty (618-709). Because of the recent development of breakwaters for a fishing harbor, the shore environments of this beach have changed significantly. In this study, the status of silt deposits and topographic changes on this beach arising from the construction of a harbor breakwater were evaluated by comparing aerial photographs taken in different years. Next, the changes in the shoreline visible from aerial photographs from 1947 to 2014 were analyzed. Lastly, the altitude of the beaches was measured using accurate survey methods. The following results were obtained: 1) coastal erosion made rock cliffs to fall off along the shore and deposited sand on this beach; 2) the more serious advances or retreats of the shoreline took place around shoreline structures; 3) sandbars and beach cliffs were formed.

PREDICTION OF TOPOGRAPHIC CHANGES ON FORESHORE AND BACKSHORE WHEN LONGSHORE SAND TRANSPORT WAS BLOCKED BY FLOODWAY

2018 ◽  
Vol 74 (2) ◽  
pp. I_871-I_876
Author(s):  
Toshinori ISHIKAWA ◽  
Takaaki UDA ◽  
Masumi SERIZAWA ◽  
Shiho MIYAHARA ◽  
Ryo MOROHASHI ◽  
...  
Keyword(s):  
Sand Transport

CHANGE IN SHORELINE CONFIGURATION AND LONGSHORE SAND TRANSPORT BETWEEN OARAI AND KASHIMA PORTS

2020 ◽  
Vol 76 (2) ◽  
pp. I_457-I_462
Author(s):  
Takaaki UDA ◽  
Masashi KAWAMATA ◽  
Shogo KIKUCHI ◽  
Yasuro OHTANI ◽  
Toshiro SAN-NAMI
Keyword(s):  
Sand Transport

scholarly journals Shoreline evolution and modern beach sand composition along a coastal stretch of the Tyrrhenian Sea, southern Italy

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Consuele Morrone ◽  
Fabio Ietto
Keyword(s):  
Southern Italy ◽  
Average Rate ◽  
Transport Processes ◽  
Beach Sand ◽  
Sand Transport ◽  
Petrographic Analysis ◽  
Tyrrhenian Sea ◽  
Evolutionary Trend ◽  
Erosion Processes ◽  
Geomorphological Analysis

AbstractThis contribution focuses on a multidisciplinary research showing the geomorphological evolution and the beach sand composition of the Tyrrhenian shoreline between Capo Suvero promontory and Gizzeria Lido village (Calabria, southern Italy). The aim of the geomorphological analysis was to reconstruct the evolutionary shoreline stages and the present-day sedimentary dynamics along approximately 6 km of coastline. The results show a general trend of beach nourishment during the period 1870–2019. In this period, the maximum shoreline accretion value was estimated equal to + 900 m with an average rate of + 6.5 m/yr. Moreover, although the general evolutionary trend is characterized by a remarkable accretion, the geomorphological analysis highlighted continuous modifications of the beaches including erosion processes. The continuous beach modifications occurred mainly between 1953 and 1983 and were caused mainly by human activity in the coastal areas and inside the hydrographic basins. The beach sand composition allowed an assessment of the mainland petrological sedimentary province and its dispersal pattern of the present coastal dynamics. Petrographic analysis of beach sands identified a lithic metamorphi-clastic petrofacies, characterized by abundant fine-grained schists and phyllites sourced from the crystalline terrains of the Coastal Range front and carried by the Savuto River. The sand is also composed of a mineral assemblage comparable to that of the Amato River provenance. In terms of framework detrital constituents of QFL (quartz:feldspars:aphanitic lithic fragments) and of essential extraclasts, such as granitoid:sedimentary:metamorphic phaneritic rock fragments (Rg:Rs:Rm), sand maturity changes moderately from backshore to shoreface, suggesting that transport processes had a little effect on sand maturity. Moreover, the modal composition suggests that the Capo Suvero promontory does not obstruct longshore sand transport from the north. Indeed, sands displaced by currents driven by storm-wave activity bypass this rocky headland.

scholarly journals TOWARD AN IMPROVED EMPIRICAL FORMULA FOR LONGSHORE SAND TRANSPORT

1988 ◽  
Vol 1 (21) ◽  
pp. 88 ◽  
Author(s):  
Nicholas C. Kraus ◽  
Kathryn J. Gingerich ◽  
Julie Dean Rosati
Keyword(s):  
Oscillatory Flow ◽  
Field Experiments ◽  
Surf Zone ◽  
Transport Rate ◽  
Sand Transport ◽  
Longshore Current ◽  
Wave Energy Dissipation ◽  
Total Transport ◽  
Local Wave ◽  
Correction Terms

This paper presents results of two field experiments performed using portable traps to obtain point measurements of the longshore sand transport rate in the surf zone. The magnitude of the transport rate per unit width of surf zone is found to depend on the product of the local wave height and mean longshore current speed, but correlation is much improved by including two correction terms, one accounting for local wave energy dissipation and the other for the fluctuation in the longshore current. The field transport rates are also found to be compatible with laboratory rates obtained under combined unidirectional and oscillatory flow. Total transport rates previously reported for this experiment program are revised with recently determined sand trapping efficiencies.

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