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Potential morphological responses of an artificial beach to a flood in extreme events: field observation and numerical modelling
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作者 Jiadong Fan Cuiping Kuang +3 位作者 Xuejian Han Lixin Gong Huixin Liu Jiabo Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期78-92,共15页
Conch Island is a typical artificial island at the Tanghe Estuary in Bohai Sea,China.To improve natural environment and boost local tourism,beach nourishment will be applied to its north-western shore.The projected be... Conch Island is a typical artificial island at the Tanghe Estuary in Bohai Sea,China.To improve natural environment and boost local tourism,beach nourishment will be applied to its north-western shore.The projected beach is landward and opposite to the Jinmeng Bay Beach.Nowadays,with climate changes,frequent heavy rainfalls in Hebei Province rise flood hazards at the Tanghe Estuary.Under this circumstance,potential influences on the projected beach of a flood are investigated for sustainable managements.A multi-coupled model is established and based on the data from field observations,where wave model,flow model and multifraction sediment transport model are included.In addition,the impacts on the projected beach of different components in extreme events are discussed,including the spring tides,storm winds,storm waves,and sediment inputs.The numerical results indicate the following result.(1)Artificial islands protect the coasts from erosion by obstructing landward waves,but rise the deposition risks along the target shore.(2)Flood brings massive sediment inputs and leads to scours at the estuary,but the currents with high sediment concentration contribute to the accretions along the target shore.(3)The projected beach mitigates flood actions and reduces the maximum mean sediment concentration along the target shore by 20%.(4)The storm winds restrict the flood and decrease the maximum mean sediment concentration by 21%.With the combined actions of storm winds and waves,the maximum value further declines by 38%.(5)A quadratic polynomial relationship between the deposition depths and the maximum sediment inputs with flood is established for estimations on the potential morphological changes after the flood process in extreme events.For the uncertainty of estuarine floods,continuous monitoring on local hydrodynamic variations and sediment characteristics at Tanghe Estuary is necessary. 展开更多
关键词 beach nourishment FLOOD artificial island sediment transport extreme events STORM
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Different responses of two adjacent artificial beaches to Typhoon Hato in Zhuhai,China
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作者 Jun ZHU Qing WANG +5 位作者 Chao ZHAN Fengjuan SUN Wenhao HUA Jianhui LIU Hongshuai QI Yu YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期511-521,共11页
Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon Hato.In this study,a fully nonlinear... Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon Hato.In this study,a fully nonlinear Boussinesq wave model(FUNWAVE)-Total Variation Diminishing(TVD)was used to distinguish the main impact factors,their relative contributions,and the hydrodynamic mechanisms underlying the different beach responses.Results show that compared to the ML beach,the main reason for the relatively weak erosion on Xiangluwan(XL)beach was the smaller beach berm height(accounting for approximately 75.9%of the erosion response).Regarding the beach with a higher berm,the stronger wave-induced undertow flow,along with the higher sediment concentration,led to a higher offshore sediment transport flux,resulting in more severe erosion relative to the beach with a smaller berm height.The second most important reason explaining the weak erosion on XL beach was the absence of seawalls(accounting for approximately 17.9%of the erosion response).Wave reflection induced by the seawall could cause higher suspended sediment concentration,resulting in a toe scouring near the seawall.The offshore submerged breakwater protected XL beach slightly(accounting for approximately 6.1%of the erosion response).Due to the higher water level induced by storm surge,most of the wave energy could penetrate through the submerged breakwater.The effect of the larger berm width of XL beach was negligible.Compared to the beach with a larger berm width,the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration,without significant changes in the erosion/deposition extent.Despite of this,the larger berm width could reduce the wave energy reaching the shoreline.This study of the storm stability of artificial beaches may be applied to beach restoration design. 展开更多
关键词 beach erosion berm height berm width SEAWALL fully nonlinear Boussinesq wave model(FUNWAVE)
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Gravity Fault Subsidence and Beach Ridges Progradation in Quinta-Cassino (RS) Coastal Plain, Brazil
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作者 Bruno Silva da Fontoura Adelir José Strieder +3 位作者 Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes Alexandre Felipe Bruch Angélica Cirolini 《Open Journal of Geology》 CAS 2024年第2期177-195,共19页
Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, howeve... Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, however, low-frequency GPR survey to investigate fault-related depositional systems at greater depths. The Quinta-Cassino area in the Rio Grande do Sul Coastal Plain (RGSCP, Brazil) shows a wide strandplain that is made off by very long, continuous, and linear geomorphic features (beach ridges). This strandplain extends for ~70 km southward. The beach ridges show low-angle truncations against the Quinta escarpment, and also truncations in the strandplain. The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;previous model assumes that no deformational episode occurred in RGSCP. The geophysical and geological surveys carried out in this area showed the existence of listric fault controlling the beach ridges in the escarpments and hanging-wall blocks. The radargrams could distinguish Pleistocene basement unit anticlockwise rotation, thickening of beach ridges radarfacies close to listric normal faults, and horst structures. These deformational features indicate that the extensional zone of a large-scale gravity-driven structure controlled the mechanical subsidence, the Holocene sedimentation and its stratigraphic and geomorphic features in the Quinta-Cassino area to build up an asymmetric delta. The results point to a new approach in dealing with RGSCP Holocene evolution. 展开更多
关键词 Gravity Tectonics Normal Faults Ground Penetrating Radar Survey beach-Ridges Progradation
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Assessment and Application of Beach Quality Based on Analytic Hierarchy Process in Yangkou Beach, Qingdao 被引量:1
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作者 LI Haimeng WANG Jingyi ZHU Chaoyue 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期151-160,共10页
The whole-beach quality assessment is the basis of building and preserving beautiful beaches.The beach quality assessment index system and assessment standard have been established based on the attributes of beaches(i... The whole-beach quality assessment is the basis of building and preserving beautiful beaches.The beach quality assessment index system and assessment standard have been established based on the attributes of beaches(including the width,slope,landform,and types),sorting coefficient,and softness degree of surface sediment.The assessment weight of each index for quality evaluation was analyzed using the analytic hierarchy process,and comprehensive scores of selected beach profiles were calculated in accordance with the light assessment standard.A beach quality evaluation model based on index weight and scores was established in this paper.The factors of 12 profiles of Yangkou Beach in Qingdao City were surveyed to carry out a quality assessment,and the comprehensive scores of each profile were calculated in accordance with the evaluation model.The results showed that the quality of Yangkou Beach can be divided into four ratings:excellent,good,medium,and poor.The excellent-quality area includes a wide and flat dry beach zone and soft,flat,and clean intertidal and subtidal zones covered with well-sorted fine sand,and leisure sports,such as volleyball,running,and swimming,are suitable for tourists.The good-quality area features a slightly narrow and dry beach zone,moderately soft and uneven intertidal and subtidal zones covered with fine sand and a small tidal gully,and a small amount of foreign matter;leisure sports,such as walking and running,are suitable for tourists.This study recommends the building of fixed drainage ditches or underground culverts to reduce the tidal gully.The medium-quality area consisted of a narrow and dry beach zone,moderately soft and uneven intertidal and subtidal zones covered by poorly sorted medium sand,a tide ditch,and a small amount of foreign matter.In this area,walking is suitable for tourists.Sand should be supplemented in the intertidal zone.The poor-quality area contained a very narrow and dry beach zone covered with poor-sorted gravel,a very chaotic intertidal zone with a considerable amount of foreign matters,such as bricks and rocks,wide tidal ditches,and an uneven subtidal zone with some reefs;leisure sports are unsuitable here.Thus,foreign matter and reefs should be removed,and the dry beach zone should be supplemented with sand.Therefore,the beach quality assessment is a very useful tool for building beautiful beaches. 展开更多
关键词 Yangkou beach assessment index analytic hierarchy process WEIGHT quality zoning
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Dynamic geomorphology and storm response characteristics of the promontory-straight beach-a case of Gulei Beach, Fujian 被引量:1
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作者 Chao Cao Zijian Mao +5 位作者 Feng Cai Hongshuai Qi Jianhui Liu Gang Lei Shaohua Zhao Gen Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期64-78,共15页
As one of the main areas of tropical storm action in the northwestern Pacific Ocean,South China experiences several typhoons each year,and coastal erosion is a problem,making the area a natural testing ground for stud... As one of the main areas of tropical storm action in the northwestern Pacific Ocean,South China experiences several typhoons each year,and coastal erosion is a problem,making the area a natural testing ground for studying the dynamic geomorphological processes and storm response of promontory-straight coasts.This study is based on three years of topographic data and remote sensing imagery of Gulei Beach and uses topographic profile morphology,single width erosion-accretion and mean change,combined with the Coastsat model to quantify the seasonal and interannual variability and storm response of the beach and to explain the evolution of shoreline change and beach dynamics geomorphology in the last decade.Gulei Beach has been in a state of overall erosion and local accretion for a long time,with relatively obvious cyclical changes;seasonal changes are also obvious,which are mainly characterized by summer accretion and winter erosion,with accretion at the top of the bay and accretion and erosion on the north and south sides of the bay corner,respectively;the seasonal erosion-accretion volume of the beach profile ranges from-80 m3/m to 95.52 m3/m,and the interannual erosion-accretion volume ranges from-69.09 m3/m to 87.31 m3/m.The response of beaches to typhoons with different paths varies greatly depending on the length,slope,orientation and scale of beach development.The large and gently developing Futou beach is less responsive to storms,while the less developed headlands in the southern Gulei Peninsula are more susceptible to disturbance by external factors and respond more strongly to typhoons.Storm distance is more influential than storm intensity.Under the influence of human activities,obvious erosion hotspots develop during normal weather,but storm processes produce redistribution of beach material patterns,and erosion hotspots disappear after storms.The results of this study enrich the theory of beach dynamics geomorphology and provide technical support for disaster prevention and mitigation,as well as ecological restoration of coastal zones. 展开更多
关键词 promontory-straight beach dynamic geomorphology storm response Gulei Peninsula
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Morphodynamic response of an embayed beach to different typhoon events with varying intensities
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作者 Lianqiang Shi Junli Guo +3 位作者 Shenliang Chen Yang Chang Daheng Zhang Zhaohui Gong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期51-63,共13页
Beach erosion has occurred globally in recent decades due to frequent and severe storms.Dongsha beach,located in Zhujiajian Island,Zhejiang Province,China,is a typical embayed sandy beach.This study focused on the mor... Beach erosion has occurred globally in recent decades due to frequent and severe storms.Dongsha beach,located in Zhujiajian Island,Zhejiang Province,China,is a typical embayed sandy beach.This study focused on the morphodynamic response of Dongsha beach to typhoon events,based on beach topographies and surficial sediment characteristics acquired before and after four typhoon events with varying intensities.The four typhoons had different effects on the topography and sediment characteristics of Dongsha beach.Typhoons Ampil and Danas caused the largest(-51.72 m3/m)and the smallest erosion(-8.01 m3/m),respectively.Remarkable alongshore patterns of beach profile volumetric changes were found after the four typhoon events,with more erosion in the southern and central parts of the beach and few changes in the northern part.Grain size coarsening and poor sorting were the main sediment patterns on the beach influenced by different typhoons.Typhoons that occurred in the same year after another typhoon enhanced the effect of the previous typhoon on sediment coarsening and sorting variability,but this cumulative effect was not found between typhoons that occurred during different years.A comparison of the collected data revealed that the topographic state of the beach before the typhoon,typhoon characteristics,and tidal conditions were possible reasons for the difference in the responses of Dongsha beach to typhoon events.More severe beach erosion was caused by typhoons with higher intensity levels and longer durations,and high tide levels during typhoons can determine the upper limit of the beach profile erosion site.Taken together,these results can be used to improve beach management for storm prevention. 展开更多
关键词 beach morphodynamic response typhoon event beach profile grain size characteristic human intervention
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Variation in cross-shore wind speeds influenced by the morphology of nourished beach
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作者 Xu Chen Jianhui Liu +5 位作者 Feng Cai Yanyu He Bailiang Li Hongshuai Qi Shaohua Zhao Gen Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期149-159,共11页
The cross-shore variation in wind speeds influenced by beach nourishment,especially the dramatic changes at the nourished berm,is important for understanding the aeolian sand transport processes that occur after beach... The cross-shore variation in wind speeds influenced by beach nourishment,especially the dramatic changes at the nourished berm,is important for understanding the aeolian sand transport processes that occur after beach nourishment,which will contribute to better beach nourishment project design on windy coasts.In this paper,the influencing factors and potential mechanism of wind speed variation at the edge of a nourished berm were studied.Field observations,together with the Duna model,were used to study the cross-shore wind speed distribution for different nourishment schemes.The results show that the nourished berm elevation and beachface slope are the main factors controlling the increase in wind speed at the berm edge.When the upper beach slope is constant,the wind speed at the berm edge has a positive linear correlation with the berm elevation.When the berm elevation remains constant,the wind speed at the berm edge is also proportional to the upper beach slope.Considering the coupling effects of nourished berm elevation and beachface slope,a model for predicting the wind speed amplification rate at the nourished berm edge was established,and the underlying coupling mechanism was illustrated. 展开更多
关键词 beach nourishment nourished beach berm cross-shore wind speed Duna model wind speed amplification rate
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Analysis of wave shoaling and shore-breakers on a low tide terrace beach based on in-situ measurements at Xisha Bay on South China coast
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作者 Yuan Li Chi Zhang +5 位作者 Hongshuai Qi Jiacheng Song Weiqi Dai Shanhang Chi Jian Shi Dake Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期175-184,共10页
Low tide terrace beach is a main beach type along South China coasts with strong tidal actions.How strong tides affect wave transformations on low tide terrace beach still remains unclear.In this study,in-situ measure... Low tide terrace beach is a main beach type along South China coasts with strong tidal actions.How strong tides affect wave transformations on low tide terrace beach still remains unclear.In this study,in-situ measurements are conducted on the low terrace beach at Xisha Bay to provide quantitative descriptions of wave shoaling and shore-breaker phenomena under the tidal effects.It is found that wave breaking is unsaturated on the low tide terrace beach at Xisha Bay.Magnitudes of wave skewness and asymmetry increase as wave shoals and achieve the maximum value at the shore-breaker,and then decrease rapidly.Mean energy dissipation rates of shore-breakers are tide-modulated since the bottom slope changes at the shoreward boundary of wave propagation in a tidal cycle.The remaining wave energy flux at the initialization of the shore-breaker is 1%–12%of offshore wave energy flux,and the energy flux ratio decreases with increasing offshore wave heights.Wave attenuation at shore-breakers can be estimated directly from offshore wave conditions based on findings in this study,favoring designs of seawalls or beach nourishment projects.Field datasets on wave transformations can also be used for verifications of wave numerical models. 展开更多
关键词 sandy beach low tide terrace waves shore-breakers South China coasts
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Using video imagery to reconstruct the 3D intertidal terrain along a beach with multiple cusps
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作者 Feng Cai Hang Yin +4 位作者 Hongshuai Qi Jixiang Zheng Yuwu Jiang Zhubin Cao Yanyu He 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期1-9,共9页
A high-frequency,high-resolution shore-based video monitoring system(VMS)was installed on a macrotidal(tidal amplitude>4 m)beach with multiple cusps along the Quanzhou coast,China.Herein,we propose a video imagery-... A high-frequency,high-resolution shore-based video monitoring system(VMS)was installed on a macrotidal(tidal amplitude>4 m)beach with multiple cusps along the Quanzhou coast,China.Herein,we propose a video imagery-based method that is coupled with waterline and water level observations to reconstruct the terrain of the intertidal zone over one tidal cycle.Furthermore,the beach cusp system(BCS)was precisely processed and embedded into the digital elevation model(DEM)to more effectively express the microrelief and detailed characteristics of the intertidal zone.During a field experiment conducted in January 2022,the reconstructed DEM was deemed satisfactory.The DEM was verified by RTK-GPS and had an average vertical root mean square error along corresponding RTK-GPS-derived intertidal profiles and corresponding BCS points of 0.134 m and 0.065 m,respectively.The results suggest that VMSs are an effective tool for investigating coastal geomorphic processes. 展开更多
关键词 intertidal terrain beach cusp video monitoring system waterline method feature embedment
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Sediment source-to-sink process variations of sandy-muddy transitional beaches and their morphological indications
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作者 Shaohua Zhao Feng Cai +4 位作者 Hongshuai Qi Jianhui Liu Chao Cao Gen Liu Gang Lei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期10-24,共15页
The clay mineralogy of 28 sandy-muddy transitional beach(SMT-Beach)sediments and surrounding mountain river sediments along the coasts of southeastern China was systematically investigated to reveal the sediment sourc... The clay mineralogy of 28 sandy-muddy transitional beach(SMT-Beach)sediments and surrounding mountain river sediments along the coasts of southeastern China was systematically investigated to reveal the sediment source-to-sink process variations of such beaches and their morphological indications.The results show that the clay mineral assemblages of these SMT-Beaches mainly comprise of almost equal illite(~30%),kaolinite(~28%),chlorite(~22%),and smectite(~20%)contents.From the surrounding mountain rivers to the SMT-Beaches,clay mineral assemblages show distinct spatial changes characterized by a large decrease(~40%)in kaolinite,whereas the other three clay minerals present relative increases,especially clear for smectite.The muddy sediment sources of SMT-Beaches inferred from the clay mineralogy are mainly derived from nearby mountain rivers coupled with long-distance transport and penetration of the Changjiang River.The sandy sediments of these beaches are predominantly sourced from nearby mountain rivers,the weathering products of surrounding rocks in both mainland and island environments,and erosion of the“Old Red Sand”and“Red Soil Platform”.However,the sandy sediment sources of the SMT-Beaches are largely reduced because of the remarkable decrease in the river fluvial supply associated with intensive human activities such as dam construction and coastal reclamation.Subsequently,the sandy sections of SMT-Beaches present clear erosion and have revealed by both time series remote sensing images and a compilation of published literature.In contrast,the muddy sediment supply of SMT-Beaches is temporarily stable and relatively constant,resulting in the landward migration of the mudflats with relative transgression or accumulation.These findings highlight that the natural evolution processes of SMT-Beaches have been greatly reshaped by intensive human activities. 展开更多
关键词 sandy-muddy transitional beach clay mineral sediment source human activity fluvial discharge morphological evolution
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Nourishment and disaster mitigation efficiency of feeding sand on the dry section of a dissipative beach
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作者 Yazhuang Zhao Hongshuai Qi +6 位作者 Shaohua Zhao Feng Cai Jianhui Liu Pu Xu Zheyu Xiao Yanyu He Zhiyong Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期138-148,共11页
To explore the nourishment effect and disaster reduction efficiency of a fully dissipative dry beach under the impact of storms,this paper uses the measured topography and hydrodynamic data to establish a one-dimensio... To explore the nourishment effect and disaster reduction efficiency of a fully dissipative dry beach under the impact of storms,this paper uses the measured topography and hydrodynamic data to establish a one-dimensional numerical model of the XBeach beach profile.By numerically modeling the change in the nourished profile for different dry beach widths under normal waves and storm conditions and the recovery process of the profile after the storm,the degree of response in dry beach nourishment for the fully dissipative beach is analyzed.The results show that under normal wave conditions,the response of the nourished dry beach is obvious.Sediment on the dry beach erodes heavily,and the shoreline moves landward over a long distance.With the increase in the width and size of the dry beach,the wave height at the bottom of the backshore profile decreases,the wave height attenuation rate increases continuously,and the wave elimination effect is remarkable.When the storm incident wave intensifies,the wave height attenuation rate of the nourished dry beach decreases,indicating that the smaller the storm intensity is,the more significant the wave reduction effect of the nourished dry beach is.At the same time,different profile arrangements of nourished dry beaches suffer from different degrees of erosion under storm conditions,with significant changes in profile morphology.With intensified storm action,the intensity of sediment erosion in the nourished dry beach increases,the nourishment is weakened,and the recovery effect of the profile after the storm is not obvious.The results of the numerical modeling highlight that the dry beach nourishment method can resist storms to a certain extent,but the overall effect is relatively limited. 展开更多
关键词 tropical storm numerical model Xbeach nourishment of dry beach disaster mitigation efficiency
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Quantitative Analysis of the Sized Ranged Plastic Debris on Beach Shoreline along the Limbe Coastline, Cameroon
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作者 Eric Esongami Ndumbe Veronica Ebot Manga +1 位作者 Josepha Tendo Foba Fabrice Lamfu Yengong 《Journal of Environmental Protection》 2023年第6期441-469,共29页
In recent years, increased interest in investigating the accumulation of sized ranged plastic debris has been observed on beaches along coastlines. The abundance and distribution of the 4M’s sized class plastic debri... In recent years, increased interest in investigating the accumulation of sized ranged plastic debris has been observed on beaches along coastlines. The abundance and distribution of the 4M’s sized class plastic debris were quantitatively assessed on five sandy beaches, in Cameroon. Duplicates of 2 × 2 m (4 m<sup>2</sup>) quadrants were sampled in each beach/month with a total of 80 quadrants. Collected plastic samples were washed, sieved and dried. Particles of size, ≥2 mm, were sorted and measured using a 30 cm ruler, and converted to mm. Overall, 12,822 particles by number (530.59 g) with a mean abundance of 40.07 items/m<sup>2</sup> (1.66 g/m<sup>2</sup>) plastic debris was recorded. ANOVA (p = 0.05) shows a linear relationship between the meso- and micro-sized classes with significantly higher abundance recorded in LDB sites. The highest abundance by weight was recorded in August and June numerically. 80% of the plastic particles were between the size range, of 5 - 20 mm by number and 6 - 100 mm by weight. Moreover, in all beaches micro-sized class plastics were dominated by number 42.40% with fragmented debris dominant, in number/weight, 54.86% (25.69%) while meso-sized class plastics were 29.28% dominated by weight, with fragmented debris type, the most prevalence in number and weight as 46.11% (26.18%). On average, color and shape fractions revealed, colored and irregularly shaped plastics were dominant with an abundance of 80.45 ± 18.17 items/m<sup>2</sup> (2.58 ± 0.68 g/m<sup>2</sup>) and 47.24 ± 20.40 items/m<sup>2</sup> (1.39 ± 0.66 g/m<sup>2</sup>). Finally, the 0.0001 g plastic debris was dominant with a concentration, of 33.68 ± 7.23 items/m<sup>2</sup>. The intense use of beaches for recreation and poor waste disposal has increased the potential for plastic contamination. 展开更多
关键词 Plastic Debris beach Size-Ranged Class 4M’s ABUNDANCE Cameroon
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The Probable Cause for Nesting Pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar Beach, North East Coast of Andaman Island, India
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作者 Arun Malarvizhi M. M. Ilaamurughu P. M. Mohan 《Open Journal of Marine Science》 2023年第1期7-27,共21页
The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with th... The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with the nesting behaviour of the Olive Ridley turtles. In the present study, characteristics of the breeding beach and nesting pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of Andaman Islands were investigated, during the nesting periods 2016-2017. The study area hosts Olive Ridley, the dominant sea turtles with more than 300 individuals nesting each year. For this study, the number of sea turtles visited, nested, the sediment characters, salinity, and temperature were taken. The exposed sandy nesting beach characteristics are prone to varying degrees of morphological changes every day. The results depict that even though similar grain size (Coarse Sand to Fine Sand and Very well sorted to Poorly Sorted), with an ambient incubating temperature, pH and salinity with wide nesting area, the selective nesting in the particular location of the beach identified because of comfortable energy conditions in the waters (1.5 m/s) favours the female turtles to reach the beach at the preferable site of Ramnagar and nest. 展开更多
关键词 Sea turtle Olive Ridley Ramnagar beach Nesting Environment Morphological Changes Sand Grain HATCHLING North Andaman
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Maredamare 2023:The international beachwear show
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《China Textile》 2023年第4期58-59,共2页
A three-day show entirely dedicated to beachwear and resortwear.From July 22 to 24,the sixteenth edition of Maredamare,the international trade show organized and promoted by Underbeach,will be held in the splendid For... A three-day show entirely dedicated to beachwear and resortwear.From July 22 to 24,the sixteenth edition of Maredamare,the international trade show organized and promoted by Underbeach,will be held in the splendid Fortezza da Basso in Florence,Italy,previewing more than two hundred and fifty beachwear collections for summer 2024.Indoor and outdoor events,fashion shows,the presentation of new trends and an area dedicated to sustainability will be on the program. 展开更多
关键词 beach FORTE RESORT
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Maredamare unveils beachwear trends for summer 2024
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《China Textile》 2023年第2期50-51,共2页
Maredamare,the international beach­wear fashion show to be held in Florence July 22-24,unveils a preview of the four major trend themes that will character­ize summer 2024.The style directions have been fine... Maredamare,the international beach­wear fashion show to be held in Florence July 22-24,unveils a preview of the four major trend themes that will character­ize summer 2024.The style directions have been fine-tuned with a great deal of forecasting work shared with the leading brands of the next edition.Sporty,retro,luminescent and artistic. 展开更多
关键词 beach forecasting DIRECTIONS
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胜利油田未动储量开发技术及实践
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作者 田同辉 孟阳 +1 位作者 石世革 王伟 《油气地质与采收率》 CAS CSCD 北大核心 2024年第5期122-129,共8页
胜利油田未动储量规模大,是油田后续建产稳产的重要接替阵地。但多年的开发实践证实,这部分储量的整体动用存在很多问题,制约着油藏效益开发和建产。针对这部分油藏品位差、动用难度大和开发效果差的特点,系统梳理了胜利油田未动储量的... 胜利油田未动储量规模大,是油田后续建产稳产的重要接替阵地。但多年的开发实践证实,这部分储量的整体动用存在很多问题,制约着油藏效益开发和建产。针对这部分油藏品位差、动用难度大和开发效果差的特点,系统梳理了胜利油田未动储量的类型及分布特征,明确了主要的未动储量类型和重点攻关目标。结合近年来在砂砾岩、滩坝砂和深层低渗透稠油等油藏类型方面的开发实践,分析了砂砾岩油藏大斜度井大规模压裂、低渗透滩坝砂油藏压驱和深层低渗透稠油油藏降黏复合压驱等3种主要的未动储量开发技术及实践。长井段大斜度井大规模压裂技术,通过地质工程一体化实现工程甜点与地质甜点的结合,在低品位砂砾岩油层中的应用大幅提高了油藏产能;压驱注水开发技术创新开发理念,实现了低渗透滩坝砂油藏补能增产的突破;降黏复合压驱开发技术通过转变开发思路,实现了深层低渗透稠油油藏效益开发的突破。这3种油藏类型从单井提产、油藏补能和低成本开发等方面实现了未动储量的有效动用,取得了良好的开发效果。开发技术的突破、开发理念的转变是未动储量有效开发的必由之路,对胜利油田其他未动储量的开发具有非常重要的示范和指导意义。 展开更多
关键词 未动储量 低品位 砂砾岩 滩坝砂 稠油
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塔里木盆地寒武系盐下白云岩成藏条件分析与勘探部署方向
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作者 马德波 王珊 +7 位作者 陈永权 曹颖辉 闫磊 杜德道 杨敏 张君龙 徐兆辉 周慧 《地质科学》 CAS CSCD 北大核心 2024年第3期744-759,共16页
塔里木盆地寒武系盐下具有优质的生储盖组合,是盆地级重大战略接替领域,但由于埋深大、层系古老,寒武系盐下勘探面临烃源岩、沉积储层与油气保存等基础地质方面诸多认识问题。本文在前人研究基础上,通过野外露头、钻井分析与区域地震大... 塔里木盆地寒武系盐下具有优质的生储盖组合,是盆地级重大战略接替领域,但由于埋深大、层系古老,寒武系盐下勘探面临烃源岩、沉积储层与油气保存等基础地质方面诸多认识问题。本文在前人研究基础上,通过野外露头、钻井分析与区域地震大剖面解释,重新认识寒武系盐下烃源岩、沉积储层、盖层与油气保存条件,结合已钻井分析,指出寒武系盐下有利勘探方向,优选有利勘探区带。结果表明:1)下寒武统玉尔吐斯组烃源岩分布受控于前寒武纪裂坳体系,主要分布在北部坳陷及周缘、塔西南地区,总面积约26.8×10^(4) km^(2)。2)寒武系盐下发育肖尔布拉克组内—中缓坡丘滩体、吾松格尔组礁后滩两套储层。肖尔布拉克组内—中缓坡丘滩体沿塔南古陆周缘分布,面积4.5×10^(4) km^(2);吾松格尔组礁后滩发育在轮南—古城台缘带内侧,面积5.3×10^(3) km^(2)。3)中寒武统膏盐岩盖层发育膏盐湖、膏云坪、泥云坪3个相带,由巴楚隆起—阿瓦提凹陷膏盐湖中心向四周呈环带状展布,总面积大约25×10^(4) km^(2)。4)基于已钻井分析,提出近源、规模优质储盖组合与古隆起背景是寒武系盐下勘探突破的方向。优选塔中北斜坡、古城—肖塘南、温宿周缘、轮南地区4个Ⅰ类有利区与麦盖提斜坡1个Ⅱ类有利区,总面积5.4×10^(4) km^(2)。研究成果对于塔里木盆地寒武系盐下勘探部署具有一定的指导意义。 展开更多
关键词 塔里木盆地 寒武系盐下 肖尔布拉克组 吾松格尔组 丘滩体 膏盐岩 油气成藏
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鄂尔多斯盆地南缘麟游-淳化地区平凉组礁滩体沉积特征及分布预测
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作者 单俊峰 金科 +6 位作者 吴炳伟 崔晓磊 崔广智 杨时杰 汪国文 吴文柱 张坤 《大庆石油地质与开发》 CAS 北大核心 2024年第2期1-9,共9页
鄂尔多斯盆地南缘平凉期发育规模生物礁滩型储层,目前对该区的研究主要集中在礁滩体的类型、成因、区域演化等方面,而对礁滩体的地球物理预测尚未开展系统研究。为了提高礁滩体的预测精度,建立礁滩体储层地震预测方法,通过野外露头实地... 鄂尔多斯盆地南缘平凉期发育规模生物礁滩型储层,目前对该区的研究主要集中在礁滩体的类型、成因、区域演化等方面,而对礁滩体的地球物理预测尚未开展系统研究。为了提高礁滩体的预测精度,建立礁滩体储层地震预测方法,通过野外露头实地踏勘,结合岩心及分析测试等资料,对镶边台地高能环境下的生物礁滩发育特征进行研究。通过已知井的井震响应特征,建立礁滩体正演模型,同时开展流体活动性、地震纹理属性分析,形成研究区礁滩体储层的地震预测方法。结果表明:鄂尔多斯盆地南缘平凉组主要发育碳酸盐岩台地边缘-浅水陆棚沉积体系;礁滩体主要分布于台地边缘亚相,多期叠置;高亮体和纹理属性对礁滩体的预测效果最好,2种方法的联合应用大大提高了礁滩体预测精度。研究成果为台缘带礁滩体平面分布规律预测和鄂尔多斯盆地南缘平凉组礁滩体的勘探开发奠定基础。 展开更多
关键词 鄂尔多斯盆地南缘 平凉组 礁滩体 镶边台地 响应特征 地震属性
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塔里木盆地塔东地区油气地质条件与有利地质体资源潜力
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作者 李强 王显东 +5 位作者 闫博 刘洋 张斌 钟拥 曹阳 邓蕊 《大庆石油地质与开发》 CAS 北大核心 2024年第4期83-94,共12页
大庆油田塔东探区主体位于塔里木盆地台盆过渡区满西台缘带,勘探程度低,资源潜力大。勘探主要集中在古城地区,未获规模突破。近年来通过老井复查、构造-岩相古地理研究,明确了台缘带油气基础地质条件,落实了成藏有利区带,拓展了塔里木... 大庆油田塔东探区主体位于塔里木盆地台盆过渡区满西台缘带,勘探程度低,资源潜力大。勘探主要集中在古城地区,未获规模突破。近年来通过老井复查、构造-岩相古地理研究,明确了台缘带油气基础地质条件,落实了成藏有利区带,拓展了塔里木盆地寒武系勘探新类型。结果表明:塔东探区发育玉满裂陷、玉都裂陷槽盆相,斜坡陆棚相等多套烃源岩;寒武系—中下奥陶统台缘带高能礁滩继承发育,多组走滑断裂控储、控藏、控富集;“黑被子”泥岩、“白被子”膏岩2套区域盖层分布广泛,源、储、盖紧密配置,具备规模成藏条件;纵向上,油气受走滑断裂及区域盖层控制,主要分布在中下奥陶统碳酸盐岩地层;横向上,以玉满、玉都裂陷槽为中心,油气规模富集;玉满奥陶系鹰山组上段断溶体、鹰山组下段礁滩-断溶复合体成藏条件优越,发育凝析气藏,是塔东最现实的效益勘探领域;寒武系盐下礁滩体、断控丘滩带源、储、盖配置好,资源潜力大,可作为增储上产的接替领域。塔东探区多领域均展现出万亿立方米的气资源规模,有望快速建成大庆油田稳油增气的重要基地。 展开更多
关键词 塔东地区 满西台缘带 烃源岩 台缘礁滩 走滑断裂 奥陶系
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2011-2015年东洞庭湖洲滩典型植物群落样方调查数据集
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作者 李旭 侯志勇 +3 位作者 曾静 易爱军 谢永宏 李峰 《中国科学数据(中英文网络版)》 CSCD 2024年第1期117-126,共10页
固定样地调查通过长期数据的积累和精准的时空对比获取生态系统动态特征,为长期的生态系统研究提供了坚实的基础。洞庭湖湿地生态系统观测研究站按中国生态系统研究网络(Chinese Ecosystem Research Network,CERN)统一的监测规范,对洞... 固定样地调查通过长期数据的积累和精准的时空对比获取生态系统动态特征,为长期的生态系统研究提供了坚实的基础。洞庭湖湿地生态系统观测研究站按中国生态系统研究网络(Chinese Ecosystem Research Network,CERN)统一的监测规范,对洞庭湖水文情势变化下,湿地生态系统中典型洲滩植被的物种组成和群落特征等指标进行长期定位监测。通过东洞庭湖三种典型湿地植物群落(苔草,南荻和水蓼)长期监测样地的数据进行加工处理,获得2011-2015年洞庭湖洲滩植物群落长期监测数据集。本数据集包含有植物种名、拉丁名、株(丛)数(株或丛/样方)、叶层平均高度(cm)、生殖枝平均高度(cm)、盖度(%)、物候期、优势种、植物种数、密度(株或丛/m~2)、优势种叶层高度(cm)、优势种生殖枝高度(cm)、总盖度(%)、地上绿色部分总干重(g/m~2),共14个指标,同时附有完整的背景信息。本数据集实行全过程数据质量控制,并由专家审核验证,确保数据时空上的相对一致和准确可靠。本数据集可以为探究洞庭湖水文情势下,洲滩湿地生态系统过程和演替趋势提供本底资料,为洞庭湖植被的遥感监测、生物多样性保护和湿地生态修复及适应性管理等提供数据支撑。 展开更多
关键词 洲滩植被 群落物种组成 洞庭湖 长期定位监测
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