The harsh natural environment of Antarctica has led to a lack of research on the presence and transport mechanisms of organophosphate esters(OPEs) within its ecosystem.In this study,we analyzed levels of 11 OPEs in ai...The harsh natural environment of Antarctica has led to a lack of research on the presence and transport mechanisms of organophosphate esters(OPEs) within its ecosystem.In this study,we analyzed levels of 11 OPEs in air,soil,and vegetation samples collected during the 2018-2019 Chinese 35th Antarctic Scientific Expedition.Additionally,a level Ⅲ fugacity model was developed to simulate the movement and fate of detected OPEs in the air,soil,and vegetation of the Fildes Peninsula.Our model indicated that the primary OPEmigration pathway was from the atmosphere to the soil.OPE transportation primarily occurred through atmospheric wet deposition and rainwater dissolution.Among the 20 transport and transformation processes,atmospheric degradation was the most significant loss mechanism.The proposed model provides a method for continued investigation into the fate of OPEs in the Fildes Peninsula ecosystem.展开更多
Three-year summertime surface atmospheric N_2O concentrations were observed for the first time on the Fildes Peninsula, maritime Antarctica, and the relationships among the N2O concentration, total atmospheric O3 amou...Three-year summertime surface atmospheric N_2O concentrations were observed for the first time on the Fildes Peninsula, maritime Antarctica, and the relationships among the N2O concentration, total atmospheric O3 amount, and sunspot number were analyzed. Solar activity had an important effect on surface N2O concentration and total O3 amount, and increases of sunspot number were followed by decreases in the N2O concentration and total O3 amount. A corresponding relationship exists between the N2O concentration and total atmospheric O3, and ozone destruction was preceded by N2O reduction. We propose that the extended solar activity in the Antarctic summer reduces the stratospheric N2O by converting it into NOx, increases the diffusion of N2O from the troposphere to the stratosphere, decreases the surface atmospheric N2O, and depletes O3 via the chemical reaction between O3 and NOx. Our observation results are consistent with the theory of solar activity regarding the formation of the Antarctic O3 hole.展开更多
King George Island, situated in the South Shetland Islands archipelago, is one of the most visited sites in Antarctica. Antarctica attracts much attention because it is one of the most sensitive areas under the influe...King George Island, situated in the South Shetland Islands archipelago, is one of the most visited sites in Antarctica. Antarctica attracts much attention because it is one of the most sensitive areas under the influence of global warming. To understand its hydrochemistry characteristics, we collected various types of water samples, including samples from streams, meltwaters, ground waters, snow and ice from around the Great Wall Station, Fildes Peninsula, King George Island, from January to February, 2015. Major ions, alkalinities, silicate, pH, dissolved oxygen, temperature, and electric conductivities were measured. Several approaches were applied to identify processes that af fect the hydrochemistry on Fildes Peninsula, including ternary diagrams, principal components analysis and cluster analysis. Our data suggest that atmospheric seasalt deposition is the main factor controlling the hydrochemistry on Fildes Peninsula. After atmospheric influences were corrected for seasalt, we defined the weathering of local rocks to be another important factor on the Peninsula's hydrochemistry. Processes such as Ca dissolution from the Ca-bearing basalt, Si loss through secondary mineralization and biological uptake influence the chemical composition of runof fs on the peninsula. Cluster analysis identified 4 groups of streams based on their hydrochemical features, which reflect their original weathering characters under icecap and the combined effects with melt snow, biological activity and the anthropogenic input.展开更多
Polycyclic aromatic hydrocarbons(PAHs)and hydroxylated polycyclic aromatic hydrocarbons(OH-PAHs)were investigated in the soil of the Fildes Peninsula,Antarctica.Various analytes were detected,and the concentration of ...Polycyclic aromatic hydrocarbons(PAHs)and hydroxylated polycyclic aromatic hydrocarbons(OH-PAHs)were investigated in the soil of the Fildes Peninsula,Antarctica.Various analytes were detected,and the concentration of OH-PAHs was 0.3001.847 ng g 1 dry weight,with the dominant components being danthron and 1-hydroxy-phenanthrene.The relationship between soil total organic matter(TOM),OH-PAHs,and the parent PAHs in the soil was studied.No significant correlation was detected between the spatial distribution of OH-PAHs and the occurrence of PAHs,whereas a positive correlation with TOM was found.展开更多
During 1985-1986, 1986-1987, and 1988-1989 expeditions on Fildes Peninsula the ground temperature was measured. A total number of 218 ground temperature data were obtained. The thermal conductivity measurements were m...During 1985-1986, 1986-1987, and 1988-1989 expeditions on Fildes Peninsula the ground temperature was measured. A total number of 218 ground temperature data were obtained. The thermal conductivity measurements were made on 121 rock samples collected during expedition. This article gives a brief analysis and summarization of these data.展开更多
After a field work on recently raised coastal features in South Shetland Islands, we conclude that there are three kinds of recent coastal features, i. e, fragmental coast, rock coast, and ice cliff coast. The process...After a field work on recently raised coastal features in South Shetland Islands, we conclude that there are three kinds of recent coastal features, i. e, fragmental coast, rock coast, and ice cliff coast. The processes and forms of the fragmental cost formed by wave action with floating ice are studied. Systematic study of the raised coasts enables us to distinguish two groups of the coasts by an elevation of 20m a. s. 1. The raised coasts above 20m a. s. 1. belong to older group and those below 20m a. s. 1. belong to younger group. Mean uplift rate of coast in this area is 6. 7 mm/a.展开更多
This article is to describe the characteristics of morphological structure of sporogona of three bryophytes observed under the SEM from the Fildes Peninsula, Antarctica, which has riched research information of bryoph...This article is to describe the characteristics of morphological structure of sporogona of three bryophytes observed under the SEM from the Fildes Peninsula, Antarctica, which has riched research information of bryophyte study of the area.展开更多
ased on the analysis of the soil-forming factors, pedogenic processes and the soil properties in the study area, this paper is to propose the soil geographico-genetic classification of maritime-climatic Sub-Antarctic ...ased on the analysis of the soil-forming factors, pedogenic processes and the soil properties in the study area, this paper is to propose the soil geographico-genetic classification of maritime-climatic Sub-Antarctic regions. The soils of the Fildes Peninsula were classified into 3 soil-orders,4 suborders and 13 soil groups, and then the relationship between the soil distribution and the environment was discussed.展开更多
Two red algae, Rhodymenia antarctica and Iridaea cordata(Rhodophyta), were employed to investigate the pollution situation along Fildes Peninsula coastline, King George Island. Ten sites from east and west coastlines ...Two red algae, Rhodymenia antarctica and Iridaea cordata(Rhodophyta), were employed to investigate the pollution situation along Fildes Peninsula coastline, King George Island. Ten sites from east and west coastlines were investigated, and the concentrations of Cu, Pb, Zn, Cd, Cr, As and Hg were determined. The metal pollution index(MPI) was used to evaluate the overall pollution level represented by the investigated sites and for interregional comparisons. The two algae exhibited different preference to special trace metal. R. antarctica could accumulate more Cd(0.63 mg kg^(-1)) and Hg(0.026 mg kg^(-1)) than I. cordata(Cd 0.34 mgkg^(-1), Hg 0.019 mg kg^(-1)). I. cordata could accumulate more As(15.53 mg kg^(-1)) than R. antarctica(10.11 mg kg^(-1)). There was no significant difference in accumulating Cu, Pb, Zn and Cr between the two algae. R. antarctica could be used to monitor Cd and Hg. I. cordata would be more appropriate for monitoring As. MPI monitored by the two algae were from 1.02 to 2.26(R. antarctica), and 1.03 to 1.25(I. cordata), respectively. Pollution situation of Fildes Peninsula was becoming serious, especially of the east coastline. The objective of this research was to gather the baseline information for trace metals investigation in Antarctic.展开更多
As for the formation of the submerged trough of Maxwell Bay and the external agent geomorphic-phenomena of Fildes Peninsula, we can use glaciated theory to explain them. Moreover, based on a large number of field inve...As for the formation of the submerged trough of Maxwell Bay and the external agent geomorphic-phenomena of Fildes Peninsula, we can use glaciated theory to explain them. Moreover, based on a large number of field investigation by foreign colleagues and the authors, we can consider that the last glaciated ice-stream which had a great effect on current periglacio-landform distribution, mainly flowed along the direction from northwest to southeast. The periglacio-geomorphic distribution of the peninsula has a deep brand of glaciated history. Three kinds of different profile assemblage features show that the periglacial landform have an internal relationship in genesis. They also show a difference between stoss and leeward slopes by glaciated effect.展开更多
Antarctic environment has valuable baseline information for understanding the global change. The objectives of this study were to investigate the impacts of human activities on Antarctic terrestrial ecosystem. Based o...Antarctic environment has valuable baseline information for understanding the global change. The objectives of this study were to investigate the impacts of human activities on Antarctic terrestrial ecosystem. Based on the investigation results and the sampling analysis of the environment of Fildes Peninsula, King George Island, Antarctica, it was shown that there are some artificial radioactive elements—? ? 137 Cs in Antarctic environment: the radioactivity of 137 Cs in the surface soil, the surface moss, the fruticose lichen and the crustaceous lichen are 6 00—14 80, 25 07, 29 04 and 58 07 Bq/kg separately; i.e. the sequence of 137 Cs specific activity is as follows: crustaceous lichen>fruticose lichen>surface moss>surface soil, which demonstrates that the crustaceous lichen is one of the most sensitive monitor ways for the effect of the long term diffusion of 137 Cs. The impacts of the scientific research activities on the partial ecosystem of Fildes Peninsula include: the changes of the landscape and the soil material have made a strong freezing thawing process, which decreases the stability of the ground surface, causes the degradation of the vegetation in the some small areas; some small lakes, runoff and lichens in middle areas of Fildes Peninsula have been affected by the wastes of the stations, in the surrounding areas of the expedition stations, the concentration of Cr, Cu, Ni, Pb and Zn in the lichen and the water are higher than that of the contrasting area. Fildes Peninsula is one of the most crowded areas of expedition stations, at some extent, the environment and terrestrial ecosystem have been affected by the human activities. The conservation of the environment and ecosystem should be an important aspect of Antarctic environmental sciences.展开更多
The volcanic rock series on the Fildes Peninsula is the product of the later subduction of the Pacific platebeneath the Antarctic plate. It consists mainly of basalt, basaltic andesite and andesite with minor dacite. ...The volcanic rock series on the Fildes Peninsula is the product of the later subduction of the Pacific platebeneath the Antarctic plate. It consists mainly of basalt, basaltic andesite and andesite with minor dacite. Itsisotopic ages range from 64.6±1 to 43±2 Ma, belonging to Palaeocene to Eocene. Volcanism in the area maybe divided into two phases. The contents of major oxides, rare earth elements (REE) and trace elements in vol-canic rocks formed in different phases show regular changes, which are mainly related to the rock associationsof these phases. Isotope geochemical studies indicate that the primitive magma in the area originating by par-tial melting in the upper mantle underwent fractional crystallization and ascended to the high-level (shallow)magma chamber. Before eruption the primitive basalt-andesitic magma was subjected to differentiation in thehigh-level magma chamber, forming zones of derivative magmas of different compositions. In various phasesmagma-conducting faults experienced periodic extension and cut through various derivative magma zones indifferent parts of the peninsula, leading to the eruption of magmas of different compositions on the surface andthe formation of volcanic rock associations of corresponding compositions.展开更多
This study applies a TuPu analysis to investigate ecological and environmental aspects of an Antarctic ice-free area, using Fildes Peninsula as an example. The TuPu unit was determined using a vector-grid mixed data m...This study applies a TuPu analysis to investigate ecological and environmental aspects of an Antarctic ice-free area, using Fildes Peninsula as an example. The TuPu unit was determined using a vector-grid mixed data model. Information from the eco-environment elements was effectively extracted, and was generalized into different classes by means of data mining technol- ogy. A series of single-factor thematic information TuPu models, such as topography, soil, animal and vegetation, and human activities for Fildes Peninsula were built in this study. The topography TuPu model contained information on elevation and slope. The soil TuPu model involved soil development stages and soil thickness information. The animal and vegetation TuPu model contained the distribution of animals, plant types, lichen cover and lichen height. The human activities TuPu model included popu- lation density and human disturbance index information. The landscape comprehensive information TuPu model of Fildes Penin- sula also was established, and contains twenty-nine landscape units and twelve types of combined environments. The study quan- titatively revealed the spatial morphology and correlation of the regional eco-environment based on the analysis of these TuPu models. From these models, we can draw the conclusion that there is a regular differentiation of eco-environment from the coastal bands to the central hills in Fildes Peninsula, and that the eco-environment condition of the eastern coasts is different from that of the western coasts. The eco-environmental spatial variation also differs greatly from north to south. Based on analysis of spatial correlation, the vegetation in Fildes Peninsula has the greatest correlation with human activity, and has a certain correlation with topography and soil. This research may provide a new technical approach and scientific basis for the in-depth study of Antarctic eco-environments.展开更多
This study confirms the presence of 17 coastal terraces on Fildes Peninsula, Antarctica based on field observations and grain size analysis. The terraces formed by isostatic uplift during climate warming and glacier m...This study confirms the presence of 17 coastal terraces on Fildes Peninsula, Antarctica based on field observations and grain size analysis. The terraces formed by isostatic uplift during climate warming and glacier melting, and each level corresponds to a relatively stable period of climate. The grain size characteristics indicate an overlapping sedimentary origin for the sediments on the coastal terraces. The consistency of regional sea level rise, climate change, and glacial area suggest the presence of similar coastal terraces on King George Island since 18.0 ka.展开更多
On the basis of the geological mapping, isotopic choronoogcal and petrological evidences, the authors suggested that the early Tertiary volcanic strata in the Fildes Peninsula could be divided into two formations and ...On the basis of the geological mapping, isotopic choronoogcal and petrological evidences, the authors suggested that the early Tertiary volcanic strata in the Fildes Peninsula could be divided into two formations and four members. The erupted centers in the peninsula were gradualy migrating from the western coast to the eastern and the subvolcanic intrusives were regularly distributed along a series of NWW-SEE trending faults. All of these were basically formed in two stages of volcanic activities from Paleocene to Eocene.展开更多
The paleomagnetis m of 109 oriented samples collected from drill cores through 5 rock units of Late Cretaceous and Early Tertiary on Fildes Peninsula were systematically studied-According to the study, the paleomagnet...The paleomagnetis m of 109 oriented samples collected from drill cores through 5 rock units of Late Cretaceous and Early Tertiary on Fildes Peninsula were systematically studied-According to the study, the paleomagnetic pole position of this area is different from the position of Australia during the 55-45 Ma period. This means that when the break - up of the Gondwanaland at 55 - 45 Ma ago, Australia was separated from the Gondwanaland, drifting southward 20°-30°Lat. and rotating 70°-80°westward and then gradually arriving at recent position . The paleolatitudinal data indicate that it is not impossible that the area studied was covered with land glacier at that time. The apparent polar wander path of Antarctica through the geological time are also roughly worked out.展开更多
Cenozoic volcanic rocks in the Fildes Peninsula are composed of High-Al basalt, basaltfc andesite, andesite, and dacite belonging to a calc-alkaline volcanic series with low-K and high-Al characteristics. Using a new ...Cenozoic volcanic rocks in the Fildes Peninsula are composed of High-Al basalt, basaltfc andesite, andesite, and dacite belonging to a calc-alkaline volcanic series with low-K and high-Al characteristics. Using a new indicator, the Sr / Ca-Ba / Ca, systematics proposed by Onuma (1980, 1981) and Sr, Ba, Ca concentrations in volcanic lavas and subvolcanic rocks, the authors find that the high-Al basaltic volcanic rocks either in volcanic strata or in subvolcanic intrusives were formed from a primary magma, in different stages through the fractional crystallization of clinopyro-xene(Cpx)and plagioclase (P1) in the process of magmatic evolution, resulting in the formation of basaltic-andesitic, andesitic and dacitic rocks.展开更多
Volcanic geological,petrological and geochemical characteristics of the Tertiary volcanic rocks from the Fildes Peninsula,West Antarctica show that magma evolution was a process of dissipation of heat energy exchanged...Volcanic geological,petrological and geochemical characteristics of the Tertiary volcanic rocks from the Fildes Peninsula,West Antarctica show that magma evolution was a process of dissipation of heat energy exchanged energy and mass occurring between the magma system and its surrounding environments, and with the feature of dynamic equilibrium and periodicity(stage). In the study volcanic rocks of different types commonly exhibit a multi-grade composite texture and the derivative magmas produced by differentiation of parent magymas in the magma chamber show a zonal structure in the high--level--magma chamber which represent self-organization phenomenon of the nonequilibrium process in magmatism. The self-organization phenomenon is dissipative structure formed under given conditions.展开更多
MT measured in Great Wall Station area shows that the electrical conductivity major axis of the Wind Valley Fault is 110°NE and the crustal thickness in the Fildes Peninsula is about 22. 3 km. The crust contains ...MT measured in Great Wall Station area shows that the electrical conductivity major axis of the Wind Valley Fault is 110°NE and the crustal thickness in the Fildes Peninsula is about 22. 3 km. The crust contains four main resistivity layers with their thicknesses being 1. 3 km, 6. 7 km, 1. 2 km and 13.1 km respectively. The upper crustal thickness is 9. 2 km and the lower crustal thickness is 13. 1 km.展开更多
基金supported by the Joint Research Project of Hainan Province(No.ZDYF2024SHFZ085)Hainan Provincial Union Project of Sanya Yazhou Bay Science and Technology City(No.2021CXLH0009)+2 种基金the National Natural Science Foundation of China(Nos.42006195 and 42376234)the Science Technology Project of Yazhou Bay Innovation Institute of Hainan Tropical Ocean University(No.2022CXYZD002)the Scientific Research of Hainan Tropical Ocean University(No.RHDRC202201).
文摘The harsh natural environment of Antarctica has led to a lack of research on the presence and transport mechanisms of organophosphate esters(OPEs) within its ecosystem.In this study,we analyzed levels of 11 OPEs in air,soil,and vegetation samples collected during the 2018-2019 Chinese 35th Antarctic Scientific Expedition.Additionally,a level Ⅲ fugacity model was developed to simulate the movement and fate of detected OPEs in the air,soil,and vegetation of the Fildes Peninsula.Our model indicated that the primary OPEmigration pathway was from the atmosphere to the soil.OPE transportation primarily occurred through atmospheric wet deposition and rainwater dissolution.Among the 20 transport and transformation processes,atmospheric degradation was the most significant loss mechanism.The proposed model provides a method for continued investigation into the fate of OPEs in the Fildes Peninsula ecosystem.
基金supported by the Key Project of National Natural Science Foundation(Grant No.40231002)the Youth Foundation of the University of Science and Technology of China(Grant NO.KA0727).
文摘Three-year summertime surface atmospheric N_2O concentrations were observed for the first time on the Fildes Peninsula, maritime Antarctica, and the relationships among the N2O concentration, total atmospheric O3 amount, and sunspot number were analyzed. Solar activity had an important effect on surface N2O concentration and total O3 amount, and increases of sunspot number were followed by decreases in the N2O concentration and total O3 amount. A corresponding relationship exists between the N2O concentration and total atmospheric O3, and ozone destruction was preceded by N2O reduction. We propose that the extended solar activity in the Antarctic summer reduces the stratospheric N2O by converting it into NOx, increases the diffusion of N2O from the troposphere to the stratosphere, decreases the surface atmospheric N2O, and depletes O3 via the chemical reaction between O3 and NOx. Our observation results are consistent with the theory of solar activity regarding the formation of the Antarctic O3 hole.
基金Supported by the Chinese Arctic and Antarctic Administration(No.2014GW08008)the SKLEC/ECNU(No.2011KYYW02)the National Natural Science Foundation of China(No.41676175)
文摘King George Island, situated in the South Shetland Islands archipelago, is one of the most visited sites in Antarctica. Antarctica attracts much attention because it is one of the most sensitive areas under the influence of global warming. To understand its hydrochemistry characteristics, we collected various types of water samples, including samples from streams, meltwaters, ground waters, snow and ice from around the Great Wall Station, Fildes Peninsula, King George Island, from January to February, 2015. Major ions, alkalinities, silicate, pH, dissolved oxygen, temperature, and electric conductivities were measured. Several approaches were applied to identify processes that af fect the hydrochemistry on Fildes Peninsula, including ternary diagrams, principal components analysis and cluster analysis. Our data suggest that atmospheric seasalt deposition is the main factor controlling the hydrochemistry on Fildes Peninsula. After atmospheric influences were corrected for seasalt, we defined the weathering of local rocks to be another important factor on the Peninsula's hydrochemistry. Processes such as Ca dissolution from the Ca-bearing basalt, Si loss through secondary mineralization and biological uptake influence the chemical composition of runof fs on the peninsula. Cluster analysis identified 4 groups of streams based on their hydrochemical features, which reflect their original weathering characters under icecap and the combined effects with melt snow, biological activity and the anthropogenic input.
基金The research was supported by the National Natural Science Foundation of China(Grant nos.41976222,41406088 and 21377032)Open Fund for the Key Laboratory of Ocean-Atmospheric Chemistry and Global Change,State Oceanic Administration,China(Grant no.GCMAC1812)+2 种基金Open Fund for the State Key Laboratory of Environmental Chemistry and Ecotoxicology,China(Grant no.KF2018-05)National Key Research and Development Project of China(Grant no.2019YF0901104)We also thank Chinese Arctic and Antarctic Administration and Polar Research Institute of China for the arrangements during the 30th Chinese National Antarctic Research Expedition in 2014.
文摘Polycyclic aromatic hydrocarbons(PAHs)and hydroxylated polycyclic aromatic hydrocarbons(OH-PAHs)were investigated in the soil of the Fildes Peninsula,Antarctica.Various analytes were detected,and the concentration of OH-PAHs was 0.3001.847 ng g 1 dry weight,with the dominant components being danthron and 1-hydroxy-phenanthrene.The relationship between soil total organic matter(TOM),OH-PAHs,and the parent PAHs in the soil was studied.No significant correlation was detected between the spatial distribution of OH-PAHs and the occurrence of PAHs,whereas a positive correlation with TOM was found.
文摘During 1985-1986, 1986-1987, and 1988-1989 expeditions on Fildes Peninsula the ground temperature was measured. A total number of 218 ground temperature data were obtained. The thermal conductivity measurements were made on 121 rock samples collected during expedition. This article gives a brief analysis and summarization of these data.
文摘After a field work on recently raised coastal features in South Shetland Islands, we conclude that there are three kinds of recent coastal features, i. e, fragmental coast, rock coast, and ice cliff coast. The processes and forms of the fragmental cost formed by wave action with floating ice are studied. Systematic study of the raised coasts enables us to distinguish two groups of the coasts by an elevation of 20m a. s. 1. The raised coasts above 20m a. s. 1. belong to older group and those below 20m a. s. 1. belong to younger group. Mean uplift rate of coast in this area is 6. 7 mm/a.
文摘This article is to describe the characteristics of morphological structure of sporogona of three bryophytes observed under the SEM from the Fildes Peninsula, Antarctica, which has riched research information of bryophyte study of the area.
文摘ased on the analysis of the soil-forming factors, pedogenic processes and the soil properties in the study area, this paper is to propose the soil geographico-genetic classification of maritime-climatic Sub-Antarctic regions. The soils of the Fildes Peninsula were classified into 3 soil-orders,4 suborders and 13 soil groups, and then the relationship between the soil distribution and the environment was discussed.
基金financially supported by the Chinese Polar Environment Comprehensive Investigation and Assessment Program (Nos. CHINRE2015-02-01, CHINARE-0401)
文摘Two red algae, Rhodymenia antarctica and Iridaea cordata(Rhodophyta), were employed to investigate the pollution situation along Fildes Peninsula coastline, King George Island. Ten sites from east and west coastlines were investigated, and the concentrations of Cu, Pb, Zn, Cd, Cr, As and Hg were determined. The metal pollution index(MPI) was used to evaluate the overall pollution level represented by the investigated sites and for interregional comparisons. The two algae exhibited different preference to special trace metal. R. antarctica could accumulate more Cd(0.63 mg kg^(-1)) and Hg(0.026 mg kg^(-1)) than I. cordata(Cd 0.34 mgkg^(-1), Hg 0.019 mg kg^(-1)). I. cordata could accumulate more As(15.53 mg kg^(-1)) than R. antarctica(10.11 mg kg^(-1)). There was no significant difference in accumulating Cu, Pb, Zn and Cr between the two algae. R. antarctica could be used to monitor Cd and Hg. I. cordata would be more appropriate for monitoring As. MPI monitored by the two algae were from 1.02 to 2.26(R. antarctica), and 1.03 to 1.25(I. cordata), respectively. Pollution situation of Fildes Peninsula was becoming serious, especially of the east coastline. The objective of this research was to gather the baseline information for trace metals investigation in Antarctic.
文摘As for the formation of the submerged trough of Maxwell Bay and the external agent geomorphic-phenomena of Fildes Peninsula, we can use glaciated theory to explain them. Moreover, based on a large number of field investigation by foreign colleagues and the authors, we can consider that the last glaciated ice-stream which had a great effect on current periglacio-landform distribution, mainly flowed along the direction from northwest to southeast. The periglacio-geomorphic distribution of the peninsula has a deep brand of glaciated history. Three kinds of different profile assemblage features show that the periglacial landform have an internal relationship in genesis. They also show a difference between stoss and leeward slopes by glaciated effect.
文摘Antarctic environment has valuable baseline information for understanding the global change. The objectives of this study were to investigate the impacts of human activities on Antarctic terrestrial ecosystem. Based on the investigation results and the sampling analysis of the environment of Fildes Peninsula, King George Island, Antarctica, it was shown that there are some artificial radioactive elements—? ? 137 Cs in Antarctic environment: the radioactivity of 137 Cs in the surface soil, the surface moss, the fruticose lichen and the crustaceous lichen are 6 00—14 80, 25 07, 29 04 and 58 07 Bq/kg separately; i.e. the sequence of 137 Cs specific activity is as follows: crustaceous lichen>fruticose lichen>surface moss>surface soil, which demonstrates that the crustaceous lichen is one of the most sensitive monitor ways for the effect of the long term diffusion of 137 Cs. The impacts of the scientific research activities on the partial ecosystem of Fildes Peninsula include: the changes of the landscape and the soil material have made a strong freezing thawing process, which decreases the stability of the ground surface, causes the degradation of the vegetation in the some small areas; some small lakes, runoff and lichens in middle areas of Fildes Peninsula have been affected by the wastes of the stations, in the surrounding areas of the expedition stations, the concentration of Cr, Cu, Ni, Pb and Zn in the lichen and the water are higher than that of the contrasting area. Fildes Peninsula is one of the most crowded areas of expedition stations, at some extent, the environment and terrestrial ecosystem have been affected by the human activities. The conservation of the environment and ecosystem should be an important aspect of Antarctic environmental sciences.
基金This research was supported by the State Antarctic Committee of China,the National Natural Science Foundation of China(Project 4870113),the Geological Foundation and the Chinese Academy of Geo1ogical Sciences
文摘The volcanic rock series on the Fildes Peninsula is the product of the later subduction of the Pacific platebeneath the Antarctic plate. It consists mainly of basalt, basaltic andesite and andesite with minor dacite. Itsisotopic ages range from 64.6±1 to 43±2 Ma, belonging to Palaeocene to Eocene. Volcanism in the area maybe divided into two phases. The contents of major oxides, rare earth elements (REE) and trace elements in vol-canic rocks formed in different phases show regular changes, which are mainly related to the rock associationsof these phases. Isotope geochemical studies indicate that the primitive magma in the area originating by par-tial melting in the upper mantle underwent fractional crystallization and ascended to the high-level (shallow)magma chamber. Before eruption the primitive basalt-andesitic magma was subjected to differentiation in thehigh-level magma chamber, forming zones of derivative magmas of different compositions. In various phasesmagma-conducting faults experienced periodic extension and cut through various derivative magma zones indifferent parts of the peninsula, leading to the eruption of magmas of different compositions on the surface andthe formation of volcanic rock associations of corresponding compositions.
文摘This study applies a TuPu analysis to investigate ecological and environmental aspects of an Antarctic ice-free area, using Fildes Peninsula as an example. The TuPu unit was determined using a vector-grid mixed data model. Information from the eco-environment elements was effectively extracted, and was generalized into different classes by means of data mining technol- ogy. A series of single-factor thematic information TuPu models, such as topography, soil, animal and vegetation, and human activities for Fildes Peninsula were built in this study. The topography TuPu model contained information on elevation and slope. The soil TuPu model involved soil development stages and soil thickness information. The animal and vegetation TuPu model contained the distribution of animals, plant types, lichen cover and lichen height. The human activities TuPu model included popu- lation density and human disturbance index information. The landscape comprehensive information TuPu model of Fildes Penin- sula also was established, and contains twenty-nine landscape units and twelve types of combined environments. The study quan- titatively revealed the spatial morphology and correlation of the regional eco-environment based on the analysis of these TuPu models. From these models, we can draw the conclusion that there is a regular differentiation of eco-environment from the coastal bands to the central hills in Fildes Peninsula, and that the eco-environment condition of the eastern coasts is different from that of the western coasts. The eco-environmental spatial variation also differs greatly from north to south. Based on analysis of spatial correlation, the vegetation in Fildes Peninsula has the greatest correlation with human activity, and has a certain correlation with topography and soil. This research may provide a new technical approach and scientific basis for the in-depth study of Antarctic eco-environments.
基金funded by the Chinese Polar Environment Comprehensive Investigation & Assessment Programs (Grant no. CHINARE2015-02-01)the Chinese Polar Scientific Strategic Research Programme (Grant no. 20120101)
文摘This study confirms the presence of 17 coastal terraces on Fildes Peninsula, Antarctica based on field observations and grain size analysis. The terraces formed by isostatic uplift during climate warming and glacier melting, and each level corresponds to a relatively stable period of climate. The grain size characteristics indicate an overlapping sedimentary origin for the sediments on the coastal terraces. The consistency of regional sea level rise, climate change, and glacial area suggest the presence of similar coastal terraces on King George Island since 18.0 ka.
文摘On the basis of the geological mapping, isotopic choronoogcal and petrological evidences, the authors suggested that the early Tertiary volcanic strata in the Fildes Peninsula could be divided into two formations and four members. The erupted centers in the peninsula were gradualy migrating from the western coast to the eastern and the subvolcanic intrusives were regularly distributed along a series of NWW-SEE trending faults. All of these were basically formed in two stages of volcanic activities from Paleocene to Eocene.
文摘The paleomagnetis m of 109 oriented samples collected from drill cores through 5 rock units of Late Cretaceous and Early Tertiary on Fildes Peninsula were systematically studied-According to the study, the paleomagnetic pole position of this area is different from the position of Australia during the 55-45 Ma period. This means that when the break - up of the Gondwanaland at 55 - 45 Ma ago, Australia was separated from the Gondwanaland, drifting southward 20°-30°Lat. and rotating 70°-80°westward and then gradually arriving at recent position . The paleolatitudinal data indicate that it is not impossible that the area studied was covered with land glacier at that time. The apparent polar wander path of Antarctica through the geological time are also roughly worked out.
文摘Cenozoic volcanic rocks in the Fildes Peninsula are composed of High-Al basalt, basaltfc andesite, andesite, and dacite belonging to a calc-alkaline volcanic series with low-K and high-Al characteristics. Using a new indicator, the Sr / Ca-Ba / Ca, systematics proposed by Onuma (1980, 1981) and Sr, Ba, Ca concentrations in volcanic lavas and subvolcanic rocks, the authors find that the high-Al basaltic volcanic rocks either in volcanic strata or in subvolcanic intrusives were formed from a primary magma, in different stages through the fractional crystallization of clinopyro-xene(Cpx)and plagioclase (P1) in the process of magmatic evolution, resulting in the formation of basaltic-andesitic, andesitic and dacitic rocks.
文摘Volcanic geological,petrological and geochemical characteristics of the Tertiary volcanic rocks from the Fildes Peninsula,West Antarctica show that magma evolution was a process of dissipation of heat energy exchanged energy and mass occurring between the magma system and its surrounding environments, and with the feature of dynamic equilibrium and periodicity(stage). In the study volcanic rocks of different types commonly exhibit a multi-grade composite texture and the derivative magmas produced by differentiation of parent magymas in the magma chamber show a zonal structure in the high--level--magma chamber which represent self-organization phenomenon of the nonequilibrium process in magmatism. The self-organization phenomenon is dissipative structure formed under given conditions.
文摘MT measured in Great Wall Station area shows that the electrical conductivity major axis of the Wind Valley Fault is 110°NE and the crustal thickness in the Fildes Peninsula is about 22. 3 km. The crust contains four main resistivity layers with their thicknesses being 1. 3 km, 6. 7 km, 1. 2 km and 13.1 km respectively. The upper crustal thickness is 9. 2 km and the lower crustal thickness is 13. 1 km.
