This paper studies. for the first time, the storm deposits of a carbonate sequence in the Sinian ZhangquFormation in northern Anhui. In the formation. a great number of calcareous trider sponge spicules were dis-cover...This paper studies. for the first time, the storm deposits of a carbonate sequence in the Sinian ZhangquFormation in northern Anhui. In the formation. a great number of calcareous trider sponge spicules were dis-covered in a distal storm turbidity sequence, which have provided further evidence for the correlation of theSinian Systems in North and South China from a view point of palaeontology.展开更多
Storm deposits or tempestites are event sequences formed by storms,requiring at least a water temperature of 26.5℃.While inland lakes are unlikely to form storm deposits because of their limited width and water tempe...Storm deposits or tempestites are event sequences formed by storms,requiring at least a water temperature of 26.5℃.While inland lakes are unlikely to form storm deposits because of their limited width and water temperature.The Upper Triassic Xujiahe Formation in the Sichuan Basin is a set of coal-bearing,clastic sequences with dominant sedimentary facies varying from braided river delta to lacustrine settings,with storm deposits widely reported.In the Zilanba of Guanyuan area,in situ tree trunks on a palaeosol surface in Member Vof the Xujiahe Formation provide new evidence of a storm event.Six fallen-down directions of nine in situ tree trunks were predominant in the NW direction,contrary to the palaeocurrent direction of the underlying strata,suggesting that the southeasterlies prevailed during the end-Triassic in the northern Sichuan Basin.Massive mud clasts were frequently recorded in sandstones of the Xujiahe Formation,as well as in the Xindianzi section.These mud clasts showed a rip-up or a plastic deformation with upside-down V-shapes,were capped on an erosional surface,showed no transport traces and were therefore interpreted as a storm lag deposit.The megamonsoonal climate prevailed during the Late Triassic,although the megamonsoons themselves could not generate a storm deposition in the Xujiahe Formation due to its low maximum surface wind speed.The driving mechanism for generating storm deposits in the Xujiahe Formation is suggested to be tropical cyclones over the Tethys Ocean moving eastward,further landfalling on the western margin of the Sichuan Basin.Statistics of storm events in the circum-Tethys region show a widespread storm surge in low latitudes during the end-Triassic.The storm deposits at the top of the Xujiahe Formation represent a sedimentary response to the end-Triassic hyperthermal event.展开更多
The relationship between storm activity and global warming remains uncertain.To better understand storm–climate relationships,coastal lagoon deposits are increasingly being investigated because they could provide hig...The relationship between storm activity and global warming remains uncertain.To better understand storm–climate relationships,coastal lagoon deposits are increasingly being investigated because they could provide high-resolution storm records long enough to cover past climate changes.However,site-specific sediment dynamics and high barriers may bias storm reconstructions.Here,we aimed to investigate these factors through the reconstruction of five distinct storm records(XCL-01,XC-03,XC-06,XC-07,XC-08)from different water depths in a lagoon with a high barrier(i.e.,Xincun Lagoon of Hainan Island).Sediment cores were characterized using high-resolution grain size and XRF measurements,to identify storm events.These data were coupled with a numerical simulation to obtain bed shear stress data with high-spatial resolution to better understand storm-induced sediment transport mechanisms.^(210) Pb dating and Pb pollution chronostratigraphic markers indicated that the chronology of the storm deposit sequences of the cores span the period between 117 a and 348 a.The grain size and XRF results indicated numerous,highly variable and short-duration fluctuations,suggesting that storm-induced coarse-grained sediments were deposited at these core sites.The inconsistent storm events recorded in these cores suggest that these sites have different preservation potentials for storm deposits.However,the consistence between storm sediment records and historical documents for Core XCL-01 indicates that high-barrier lagoons could provide long-term storm event records with high preservation potential.展开更多
Based on over 10 years’ field survey and laboratory work, it has been confirmed that a series of storm deposits have been developed on different geomorphological and sedimentological zones in the Changjiang Delta, co...Based on over 10 years’ field survey and laboratory work, it has been confirmed that a series of storm deposits have been developed on different geomorphological and sedimentological zones in the Changjiang Delta, covering marsh lowland, shelly and sandy cheniers, tidal flats, the delta front and prodelta. The storm deposit model of the Changjiang Delta is particularly characterized by the hummocky cross stratification found above the normal wave base.展开更多
The formation of beach rocks has a close relationship to storm deposits, denoted by beach and storm processes in association with depositional characteristics of the beach rocks found in Pui O and Lower Cheung Sha bay...The formation of beach rocks has a close relationship to storm deposits, denoted by beach and storm processes in association with depositional characteristics of the beach rocks found in Pui O and Lower Cheung Sha bays on the southern coast of Lantau Island, Hong Kong. Although not all beach rocks have an origin of storm deposits, it is certain that some of them with very coarse shells and shell fragments developing on sandy beaches originate from storm deposits. The cementation of beach rocks on a beach was affected directly by the texture and structure of the beach rocks and wave energy varying along the beach.展开更多
The Bohai Sea is influenced by numerous extreme oceanic wave events in history.However,it is often difficult to determine the types of these events due to the lack of detailed historical records,causing uncertainty in...The Bohai Sea is influenced by numerous extreme oceanic wave events in history.However,it is often difficult to determine the types of these events due to the lack of detailed historical records,causing uncertainty in the reconstruction of historical coastal disasters.We investigated an anomalous sand layer in the Xiliyu Village by the coast of Laizhou Bay,Shandong,from which an extreme event deposit was identified using a multi-proxy approach including grain size distribution,geochemistry,and magnetic susceptibility.This event was dated 2700–3100 a bp,and caused inundation of a large coastal area of Laizhou Bay.By comparing historical records with instrumental data,we believe that the event deposit was generated by a severe storm surge with wind speed of>34.9 m/s.展开更多
Dustfall is a major threat to agricultural and industrial infrastructures, as well as to other aspects of livelihood. Dustfall associated to a severe dust storm that hit the Al-Ahsa Oasis of Saudi Arabia during 12-13 ...Dustfall is a major threat to agricultural and industrial infrastructures, as well as to other aspects of livelihood. Dustfall associated to a severe dust storm that hit the Al-Ahsa Oasis of Saudi Arabia during 12-13 March 2014 is discussed in this paper. The storm caused widespread and heavy dust deposition. A dramatic decrease in the visibility coincided with the storm, and the average dust concentrations recorded during a peak 10-hour period were 6772, 5862.4 and 451.1 μg/m3 for total suspended particles (TSP), particulate matter smaller than or equal to 10 μm (PM10) and those smaller than or equal to 2.5 μm (PM2.5), respectively. The lowest visibility was 200 m, and the wind speed increased to 17.5 m/s from the north. The average daily dust deposited in the study area during the event was 12.84 (SD = 1.2) g/(m2?d). The dust samples comprised insoluble dust (48.5%) and soluble dust (51.5%). Based on the Munsell color system, the final color description of the falling dust was 10 YR/6/3. A microphotograph of the dustfall (settleable particulate matter) captured by a stereo dissection microscope shows that the dust particles had various colors and sizes, and they contained fibers and vegetative debris).展开更多
文摘This paper studies. for the first time, the storm deposits of a carbonate sequence in the Sinian ZhangquFormation in northern Anhui. In the formation. a great number of calcareous trider sponge spicules were dis-covered in a distal storm turbidity sequence, which have provided further evidence for the correlation of theSinian Systems in North and South China from a view point of palaeontology.
基金co-sponsored by the National Natural Science Foundation of China(Grant Nos.41972120,42172129)the State Key Laboratory of Palaeobiology and Stratigraphy(Grant No.173131)。
文摘Storm deposits or tempestites are event sequences formed by storms,requiring at least a water temperature of 26.5℃.While inland lakes are unlikely to form storm deposits because of their limited width and water temperature.The Upper Triassic Xujiahe Formation in the Sichuan Basin is a set of coal-bearing,clastic sequences with dominant sedimentary facies varying from braided river delta to lacustrine settings,with storm deposits widely reported.In the Zilanba of Guanyuan area,in situ tree trunks on a palaeosol surface in Member Vof the Xujiahe Formation provide new evidence of a storm event.Six fallen-down directions of nine in situ tree trunks were predominant in the NW direction,contrary to the palaeocurrent direction of the underlying strata,suggesting that the southeasterlies prevailed during the end-Triassic in the northern Sichuan Basin.Massive mud clasts were frequently recorded in sandstones of the Xujiahe Formation,as well as in the Xindianzi section.These mud clasts showed a rip-up or a plastic deformation with upside-down V-shapes,were capped on an erosional surface,showed no transport traces and were therefore interpreted as a storm lag deposit.The megamonsoonal climate prevailed during the Late Triassic,although the megamonsoons themselves could not generate a storm deposition in the Xujiahe Formation due to its low maximum surface wind speed.The driving mechanism for generating storm deposits in the Xujiahe Formation is suggested to be tropical cyclones over the Tethys Ocean moving eastward,further landfalling on the western margin of the Sichuan Basin.Statistics of storm events in the circum-Tethys region show a widespread storm surge in low latitudes during the end-Triassic.The storm deposits at the top of the Xujiahe Formation represent a sedimentary response to the end-Triassic hyperthermal event.
基金The National Natural Science Foundation of China under contract Nos 41706096 and 41530962the Research Startup Project of Jiangsu Normal University under contract No.19XSRX006+2 种基金the Opening Foundation of Hainan Key Laboratory of Marine Geological Resources and Environment under contract No.HNHYDZZYHJKF005the High-level Talent Program of Basic and Applied Basic Research Programs(Field of Natural Science)in Hainan Province under contract No.2019RC349a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘The relationship between storm activity and global warming remains uncertain.To better understand storm–climate relationships,coastal lagoon deposits are increasingly being investigated because they could provide high-resolution storm records long enough to cover past climate changes.However,site-specific sediment dynamics and high barriers may bias storm reconstructions.Here,we aimed to investigate these factors through the reconstruction of five distinct storm records(XCL-01,XC-03,XC-06,XC-07,XC-08)from different water depths in a lagoon with a high barrier(i.e.,Xincun Lagoon of Hainan Island).Sediment cores were characterized using high-resolution grain size and XRF measurements,to identify storm events.These data were coupled with a numerical simulation to obtain bed shear stress data with high-spatial resolution to better understand storm-induced sediment transport mechanisms.^(210) Pb dating and Pb pollution chronostratigraphic markers indicated that the chronology of the storm deposit sequences of the cores span the period between 117 a and 348 a.The grain size and XRF results indicated numerous,highly variable and short-duration fluctuations,suggesting that storm-induced coarse-grained sediments were deposited at these core sites.The inconsistent storm events recorded in these cores suggest that these sites have different preservation potentials for storm deposits.However,the consistence between storm sediment records and historical documents for Core XCL-01 indicates that high-barrier lagoons could provide long-term storm event records with high preservation potential.
文摘Based on over 10 years’ field survey and laboratory work, it has been confirmed that a series of storm deposits have been developed on different geomorphological and sedimentological zones in the Changjiang Delta, covering marsh lowland, shelly and sandy cheniers, tidal flats, the delta front and prodelta. The storm deposit model of the Changjiang Delta is particularly characterized by the hummocky cross stratification found above the normal wave base.
文摘The formation of beach rocks has a close relationship to storm deposits, denoted by beach and storm processes in association with depositional characteristics of the beach rocks found in Pui O and Lower Cheung Sha bays on the southern coast of Lantau Island, Hong Kong. Although not all beach rocks have an origin of storm deposits, it is certain that some of them with very coarse shells and shell fragments developing on sandy beaches originate from storm deposits. The cementation of beach rocks on a beach was affected directly by the texture and structure of the beach rocks and wave energy varying along the beach.
基金Supported by the National Natural Science Foundation of China(Nos.41706096,41530962,41771218)the Research Start-up Project of Jiangsu Normal University(No.19XSRX006)the Opening Foundation of Hainan Key Laboratory of Marine Geological Resources and Environment(No.HNHYDZZYHJKF005)。
文摘The Bohai Sea is influenced by numerous extreme oceanic wave events in history.However,it is often difficult to determine the types of these events due to the lack of detailed historical records,causing uncertainty in the reconstruction of historical coastal disasters.We investigated an anomalous sand layer in the Xiliyu Village by the coast of Laizhou Bay,Shandong,from which an extreme event deposit was identified using a multi-proxy approach including grain size distribution,geochemistry,and magnetic susceptibility.This event was dated 2700–3100 a bp,and caused inundation of a large coastal area of Laizhou Bay.By comparing historical records with instrumental data,we believe that the event deposit was generated by a severe storm surge with wind speed of>34.9 m/s.
文摘Dustfall is a major threat to agricultural and industrial infrastructures, as well as to other aspects of livelihood. Dustfall associated to a severe dust storm that hit the Al-Ahsa Oasis of Saudi Arabia during 12-13 March 2014 is discussed in this paper. The storm caused widespread and heavy dust deposition. A dramatic decrease in the visibility coincided with the storm, and the average dust concentrations recorded during a peak 10-hour period were 6772, 5862.4 and 451.1 μg/m3 for total suspended particles (TSP), particulate matter smaller than or equal to 10 μm (PM10) and those smaller than or equal to 2.5 μm (PM2.5), respectively. The lowest visibility was 200 m, and the wind speed increased to 17.5 m/s from the north. The average daily dust deposited in the study area during the event was 12.84 (SD = 1.2) g/(m2?d). The dust samples comprised insoluble dust (48.5%) and soluble dust (51.5%). Based on the Munsell color system, the final color description of the falling dust was 10 YR/6/3. A microphotograph of the dustfall (settleable particulate matter) captured by a stereo dissection microscope shows that the dust particles had various colors and sizes, and they contained fibers and vegetative debris).
