Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of Mexico.The main aim of this study is to infer the weather...Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of Mexico.The main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach sediments.The sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and zircon.Both beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic sediments.The chemical index of weathering(CIW’)indicates intense weathering in the source area.The quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical origin.Mechanical features such as fractures,pits,percussion marks,abrasion fatigue,and V-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian environments.The chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine environment.The mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine environment.Major and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),Sierra Madre Oriental(SMOr)and Oaxaquia terranes.The major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.展开更多
Zircons are abundant in the beach sediments.In this study,surface microtexture,mineralogy,bulk sediment geochemistry,trace element composition and U−Pb isotopic geochronology of detrital zircons collected from the Ria...Zircons are abundant in the beach sediments.In this study,surface microtexture,mineralogy,bulk sediment geochemistry,trace element composition and U−Pb isotopic geochronology of detrital zircons collected from the Riachuelos and Palma Sola beach areas,southwestern Gulf of Mexico were performed to infer the sediment provenance and palaeoenvironment.The zircon microtexture was categorized as mechanically-and/or chemically-induced features.The weathering index values for the Riachuelos(~72−77)and Palma Sola(~71−74)beach sediments indicated moderate weathering of both of the two source areas.The major and trace element data of bulk sediments suggested passive margin settings for the two areas.The trace elemental ratios and chondrite-normalized rare earth element(REE)patterns of bulk sediments revealed that the sediments were likely sourced by felsic and intermediate igneous rocks.And the zircon Th/U ratios(mostly more than 0.2)and zircon REE patterns(with negative Eu and positive Ce anomalies)suggested a magmatic origin for both of the beach sediments from these two areas.Two distinct zircon age peaks respectively belonging to the Paleozoic and the Cenozoic were identified both in the Riachuelos and Palma Sola beach sediments.Zircon geochronology comparison research between the Riachuelos−Palma Sola beach sediments and potential source areas in SW Gulf of Mexico revealed that the source terrane supplied the Paleozoic zircons of this study was identified as the Mesa Central Province(MCP),and the Cenozoic zircons were transported from the nearby Eastern Alkaline Province(EAP).Moreover,although the Precambrian zircons were very few in the studied sediments,their geochronology and geochemistry results still could infer that they were contributed by the source terranes of Grenvillian igneous suites in the Oaxaca and the Chiapas Massif Complexes.展开更多
Microplastics(MPs)have been recognized as one of the biggest environmental challenges in marine ecosystems.Despite the extensive existing research knowledge on MPs,the origin,transport and deposition of MPs in beach s...Microplastics(MPs)have been recognized as one of the biggest environmental challenges in marine ecosystems.Despite the extensive existing research knowledge on MPs,the origin,transport and deposition of MPs in beach sediment is still unclear.This review highlights the global occurrence,spatiotemporal distribution,sources,transport and accumulation of MPs on about 1700 world’s beaches,exploring the existing connotions on the influence of external mechanisms,internal mechanisms and local beach characteristics on MPs found in beach sediment.This review further highlights the challenges and future research potential of MPs in beach sediment.The review revealed 59.4%of studies were using“n/kg”as a unit,30.8%using“n/m2”as a unit,and 9.8%using both units.Most paper on beach microplastics are published from Asia(45.1%)with India having a global percentage of 13.8.The summary of this review indicated that the distribution of microplactic abundance in beach sediment<100 n/kg(39.5%)and 100–500 n/kg(36.4%),1000–5000 n/kg(12.3%),500–1000 n/kg(6.8%)and>5000 n/kg(4.9%)with beaches in Africa,Asia,Europe and North America recorded high MP abundance(>1000 n/kg).This review clarifies the need to improve the research knowledge of MPs in beach sediment by creating a global database to access the existing threat;using a standard measuring method and unit for identification of results.Ultimately,we suggest the implementation of holistic management strategy for MP pollution in beach sediment,most importantly,by focusing on the elimination of fibre to drastically reduce the MP pollution.展开更多
The mineralogy, bulk sediment geochemical composition, and U–Pb ages of detrital zircons retrieved from the Barra del Tordo(Tordo) and Tesoro beach sediments in the northwestern Gulf of Mexico were analyzed to determ...The mineralogy, bulk sediment geochemical composition, and U–Pb ages of detrital zircons retrieved from the Barra del Tordo(Tordo) and Tesoro beach sediments in the northwestern Gulf of Mexico were analyzed to determine their provenance. The beach sediments are mainly composed of quartz, ilmenite, magnetite, titanite,zircon, and anorthite. The weathering proxies such as the Chemical Index of Alteration(CIA), Chemical Index of Weathering(CIW), and Plagioclase Index of Alteration(PIA), reveal a moderate-to-high intensity of weathering in the source area. The chondrite-normalized rare earth element(REE) patterns are similar to felsic igneous rocks, with large negative europium anomaly(Eu/Eu^(*)= ~ 0.47–0.80 and ~ 0.57–0.67 in the Tordo and Tesoro beach sediments,respectively).Three major zircon U–Pb age groups are identified in the Tordo and Tesoro beach sediments, i.e., Proterozoic(~2039–595 Ma), Mesozoic(~ 244–70.3 Ma), and Cenozoic(~ 65.9–1.2 Ma). The differences of the zircon age spectrum between the Tordo and Tesoro beach sediments are not significant. The comparison of zircon U–Pb ages in this study with ages of potential source terranes suggests that the Mesozoic and Cenozoic zircons of the studied Tordo and Tesoro beach sediments were derived from the Eastern Alkaline Province(EAP) and Mesa Central Province(MCP). Similarly, the likely sources for the Proterozoic zircons were the Sierra Madre Oriental(SMOr) and Oaxaquia in the northwestern Gulf of Mexico. The results of this study further indicate that the sediments delivered to the beaches by rivers and redistributed by longshore currents were crucial in determining the sediment provenance.展开更多
Glacio-isostatic adjustment(GIA)and tectonic activity are important factors in the formation of marine terraces.Late Holocene wave-cut benches in the eastern part of the West Sea of Korea,also called the Yellow Sea,ca...Glacio-isostatic adjustment(GIA)and tectonic activity are important factors in the formation of marine terraces.Late Holocene wave-cut benches in the eastern part of the West Sea of Korea,also called the Yellow Sea,can be divided into two steps:531 cm above sea level(ASL)for the upper bench(T2)and 464-481 cm ASL for the lower bench(T1).Sediments on the benches a re classified into four units,and are interpreted to be beach deposits acco rding to gravel shape,textu re,and seaward inclination.The ove rlying sediment indicates that T2 was formed at approximately 530 cm ASL before 2900 yr BP,and T1 at approximately 460-480 cm ASL before 1520 yr BP.Late Holocene(4000-2000 yr BP)relative sea level(RSL)curves based on GIA models are inconsistent with the wave-cut bench elevations.Comparing T1 and T2 benches to the RSL curves of the West Sea,the upper and the lower benches were uplifted by approximately 5-8 m and 4-7 m,respectively.Although the area is several hundred kilometers away from plate boundaries,the high frequency of earthquakes in the West Sea may have induced the uplift of wave-cut benches during the last 2000 years.These indicate that the west coast of the Korean Peninsula(KP)should no longer be considered an area of subsidence,but be assigned to a regime of uplift during the late Holocene.展开更多
Storm surges and the discharge of high-level pond aquaculture effluent(HPAE)are critical factors influencing the erosion and deposition dynamics of sandy coasts in South China.Understanding the mechanisms by which the...Storm surges and the discharge of high-level pond aquaculture effluent(HPAE)are critical factors influencing the erosion and deposition dynamics of sandy coasts in South China.Understanding the mechanisms by which these factors affect sediment grain size and shape distribution patterns is significant for ecological disaster mitigation and restoration of sandy coastlines.This study examines sediment samples collected from beaches in Western Guangdong,impacted by HPAE,two days and six days after the landfall of Typhoon“Chaba”(No.2203).We analyze grain size parameters(mean size,sorting coefficient,skewness,and kurtosis)and shape parameters(sphericity,aspect ratio,convexity,circularity,symmetry),focusing on their characteristic values and spatial distribution patterns,as well as the underlying reasons for their similarities and differences.The results indicate that:(1)From two to six days post-typhoon,sediments on the affected beaches near the shore become coarser and less well-sorted,while sediments in the middle region become finer and better sorted.On the unaffected beaches,sediments near the shore become coarser,and those further offshore become finer,with no consistent pattern in sorting coefficient;(2)Landward sediments of the affected beaches exhibit a shift towards a more flattened shape,whereas sediments on the unaffected beaches trend towards a more rounded shape;(3)The correlation between the mean size,kurtosis,and grain shape parameters of the affected beaches weakens,while the correlation between the sorting coefficient and skewness strengthens.In contrast,the unaffected beaches exhibits the opposite trends.This study provides a case for understanding the impact mechanisms of sediment grain size and shape distribution under the combined influence of storms and HPAE.The findings contribute to a deeper understanding of sediment dynamics and the role of marine aquaculture in shaping sandy coastal geomorphology.展开更多
基金Newton Advanced Fellowship award-The Royal Society,UK[grant#NA160116]National Council of Humanities Science and Technology(CONAHCYT),Mexico[grant#1101236].
文摘Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of Mexico.The main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach sediments.The sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and zircon.Both beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic sediments.The chemical index of weathering(CIW’)indicates intense weathering in the source area.The quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical origin.Mechanical features such as fractures,pits,percussion marks,abrasion fatigue,and V-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian environments.The chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine environment.The mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine environment.Major and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),Sierra Madre Oriental(SMOr)and Oaxaquia terranes.The major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.
基金This study was supported by the Consejo Nacional de Ciencia y Tecnologfa(CONACyT)(Project No.Al-S-21287)Direcci6n General de Asuntos del Personal Academico(DGAPA)—Programa de Apoyoa Proyectos de Investigacione Innovacion Tecnologia(PAPIIT)(Project No.IN 107020)Instituto de Ciencias del Mary Limnologia Institutional Fund(Project No.616).
文摘Zircons are abundant in the beach sediments.In this study,surface microtexture,mineralogy,bulk sediment geochemistry,trace element composition and U−Pb isotopic geochronology of detrital zircons collected from the Riachuelos and Palma Sola beach areas,southwestern Gulf of Mexico were performed to infer the sediment provenance and palaeoenvironment.The zircon microtexture was categorized as mechanically-and/or chemically-induced features.The weathering index values for the Riachuelos(~72−77)and Palma Sola(~71−74)beach sediments indicated moderate weathering of both of the two source areas.The major and trace element data of bulk sediments suggested passive margin settings for the two areas.The trace elemental ratios and chondrite-normalized rare earth element(REE)patterns of bulk sediments revealed that the sediments were likely sourced by felsic and intermediate igneous rocks.And the zircon Th/U ratios(mostly more than 0.2)and zircon REE patterns(with negative Eu and positive Ce anomalies)suggested a magmatic origin for both of the beach sediments from these two areas.Two distinct zircon age peaks respectively belonging to the Paleozoic and the Cenozoic were identified both in the Riachuelos and Palma Sola beach sediments.Zircon geochronology comparison research between the Riachuelos−Palma Sola beach sediments and potential source areas in SW Gulf of Mexico revealed that the source terrane supplied the Paleozoic zircons of this study was identified as the Mesa Central Province(MCP),and the Cenozoic zircons were transported from the nearby Eastern Alkaline Province(EAP).Moreover,although the Precambrian zircons were very few in the studied sediments,their geochronology and geochemistry results still could infer that they were contributed by the source terranes of Grenvillian igneous suites in the Oaxaca and the Chiapas Massif Complexes.
基金funded jointly by the Special Survey of Basic Scientific and Technological Resources(2022FY202402)the General Program of National Natural Science Foundation of China(42376163)+1 种基金the Shandong Provincial Natural Science Foundation,China(ZR2022 MD109)National Key Research and Development Program(2016YFC0402602).
文摘Microplastics(MPs)have been recognized as one of the biggest environmental challenges in marine ecosystems.Despite the extensive existing research knowledge on MPs,the origin,transport and deposition of MPs in beach sediment is still unclear.This review highlights the global occurrence,spatiotemporal distribution,sources,transport and accumulation of MPs on about 1700 world’s beaches,exploring the existing connotions on the influence of external mechanisms,internal mechanisms and local beach characteristics on MPs found in beach sediment.This review further highlights the challenges and future research potential of MPs in beach sediment.The review revealed 59.4%of studies were using“n/kg”as a unit,30.8%using“n/m2”as a unit,and 9.8%using both units.Most paper on beach microplastics are published from Asia(45.1%)with India having a global percentage of 13.8.The summary of this review indicated that the distribution of microplactic abundance in beach sediment<100 n/kg(39.5%)and 100–500 n/kg(36.4%),1000–5000 n/kg(12.3%),500–1000 n/kg(6.8%)and>5000 n/kg(4.9%)with beaches in Africa,Asia,Europe and North America recorded high MP abundance(>1000 n/kg).This review clarifies the need to improve the research knowledge of MPs in beach sediment by creating a global database to access the existing threat;using a standard measuring method and unit for identification of results.Ultimately,we suggest the implementation of holistic management strategy for MP pollution in beach sediment,most importantly,by focusing on the elimination of fibre to drastically reduce the MP pollution.
基金Consejo Nacional de Ciencia y Tecnologia (CONACy T),Project Number A1-S-21287Direccion General de Asuntos del Personal Academico (DGAPA)—Programa de Apoyo a Proyectos de Investigacion e Innovación Tecnologia (PAPIIT),Project Number IN107020Instituto de Ciencias del Mar y Limnologia Institutional Fund Number 616。
文摘The mineralogy, bulk sediment geochemical composition, and U–Pb ages of detrital zircons retrieved from the Barra del Tordo(Tordo) and Tesoro beach sediments in the northwestern Gulf of Mexico were analyzed to determine their provenance. The beach sediments are mainly composed of quartz, ilmenite, magnetite, titanite,zircon, and anorthite. The weathering proxies such as the Chemical Index of Alteration(CIA), Chemical Index of Weathering(CIW), and Plagioclase Index of Alteration(PIA), reveal a moderate-to-high intensity of weathering in the source area. The chondrite-normalized rare earth element(REE) patterns are similar to felsic igneous rocks, with large negative europium anomaly(Eu/Eu^(*)= ~ 0.47–0.80 and ~ 0.57–0.67 in the Tordo and Tesoro beach sediments,respectively).Three major zircon U–Pb age groups are identified in the Tordo and Tesoro beach sediments, i.e., Proterozoic(~2039–595 Ma), Mesozoic(~ 244–70.3 Ma), and Cenozoic(~ 65.9–1.2 Ma). The differences of the zircon age spectrum between the Tordo and Tesoro beach sediments are not significant. The comparison of zircon U–Pb ages in this study with ages of potential source terranes suggests that the Mesozoic and Cenozoic zircons of the studied Tordo and Tesoro beach sediments were derived from the Eastern Alkaline Province(EAP) and Mesa Central Province(MCP). Similarly, the likely sources for the Proterozoic zircons were the Sierra Madre Oriental(SMOr) and Oaxaquia in the northwestern Gulf of Mexico. The results of this study further indicate that the sediments delivered to the beaches by rivers and redistributed by longshore currents were crucial in determining the sediment provenance.
基金supported by grant 2017-MOIS31-006 from the Research and Development of Active Faults of Korea Peninsula funded by the Korean Ministry of Public Safety and Security (MPSS)by grant NP2018-017 from the Research on Geologic Hazard Assessment of Large Fault Systems Focusing on the Central Region of the Yangsan from the Basic Research Project of the Korea Institute of Geoscience+1 种基金Mineral Resources (KIGAM) funded by the Korean Ministry of Science and ICT.S.K.appreciate the partialsupport by the NRF-2017R1A6AIA07015374 (Multi-disciplinary study for assessment of large earthquake potentials in the Korean Peninsula)NRF-2019R1A2C1002211 through the National Research Foundation of Korea funded by the Ministry of Science and ICT,Korea
文摘Glacio-isostatic adjustment(GIA)and tectonic activity are important factors in the formation of marine terraces.Late Holocene wave-cut benches in the eastern part of the West Sea of Korea,also called the Yellow Sea,can be divided into two steps:531 cm above sea level(ASL)for the upper bench(T2)and 464-481 cm ASL for the lower bench(T1).Sediments on the benches a re classified into four units,and are interpreted to be beach deposits acco rding to gravel shape,textu re,and seaward inclination.The ove rlying sediment indicates that T2 was formed at approximately 530 cm ASL before 2900 yr BP,and T1 at approximately 460-480 cm ASL before 1520 yr BP.Late Holocene(4000-2000 yr BP)relative sea level(RSL)curves based on GIA models are inconsistent with the wave-cut bench elevations.Comparing T1 and T2 benches to the RSL curves of the West Sea,the upper and the lower benches were uplifted by approximately 5-8 m and 4-7 m,respectively.Although the area is several hundred kilometers away from plate boundaries,the high frequency of earthquakes in the West Sea may have induced the uplift of wave-cut benches during the last 2000 years.These indicate that the west coast of the Korean Peninsula(KP)should no longer be considered an area of subsidence,but be assigned to a regime of uplift during the late Holocene.
基金supported by the Innovation Driven Development Foundation of Guangxi(No.AD22080035)the Open Project Funding of the Key Laboratory of Tropical Marine Ecosystem and Bioresource,Ministry of Natural Resources(No.2023-QN04)the Program for Scientific Research Start-up Funds of Guangdong Ocean University(No.060302112304).
文摘Storm surges and the discharge of high-level pond aquaculture effluent(HPAE)are critical factors influencing the erosion and deposition dynamics of sandy coasts in South China.Understanding the mechanisms by which these factors affect sediment grain size and shape distribution patterns is significant for ecological disaster mitigation and restoration of sandy coastlines.This study examines sediment samples collected from beaches in Western Guangdong,impacted by HPAE,two days and six days after the landfall of Typhoon“Chaba”(No.2203).We analyze grain size parameters(mean size,sorting coefficient,skewness,and kurtosis)and shape parameters(sphericity,aspect ratio,convexity,circularity,symmetry),focusing on their characteristic values and spatial distribution patterns,as well as the underlying reasons for their similarities and differences.The results indicate that:(1)From two to six days post-typhoon,sediments on the affected beaches near the shore become coarser and less well-sorted,while sediments in the middle region become finer and better sorted.On the unaffected beaches,sediments near the shore become coarser,and those further offshore become finer,with no consistent pattern in sorting coefficient;(2)Landward sediments of the affected beaches exhibit a shift towards a more flattened shape,whereas sediments on the unaffected beaches trend towards a more rounded shape;(3)The correlation between the mean size,kurtosis,and grain shape parameters of the affected beaches weakens,while the correlation between the sorting coefficient and skewness strengthens.In contrast,the unaffected beaches exhibits the opposite trends.This study provides a case for understanding the impact mechanisms of sediment grain size and shape distribution under the combined influence of storms and HPAE.The findings contribute to a deeper understanding of sediment dynamics and the role of marine aquaculture in shaping sandy coastal geomorphology.
