We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series...We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series chronological studies, analysis of major and minor elements performed by X-ray fluorescence spectrometry （XRF） and inductively coupled plasma-mass spectrometer （ICPMS）, three major accretion periods and corresponding paleocnvironments can be ascertained. The first period is a faster accretion period in the terminal Late Miocene to the Early Pliocene with looser structure and higher volcanic detritus content, corresponding to the active Antarctic bottom waters and depressed temperature from the intermediate Middle Miocene to the Early Pliocene. The second period is a pulse of pelagic clay deposition at the Early to Middle Pliocene, reflecting the shrinkage of the Antarctic bottom waters and the global temperature elevation of this period. The third period is a slower accretion period from the Middle Pliocene, which indicates the more violent activity of Antarctic bottom waters once again and more depressed temperature than the first period, facilitating the accretion of a more compact and pure ferromanganese zone. The paleoceanographic histories of these studied areas had not been made clear in previous research.展开更多
In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-...In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-derived type granitoids can be generalized as follows: (1) Two suites ofsource strata for Magmatism-the Pre-Sinian and the Lower Sinianl here the unity of the old foldbasement, the source strata for magmatism and the source strata for metallization are particularlyhighlighted. (2) Multi-stage melting of source strata for magmatism resulting in the formation ofmajor ore-related granites of three different stages (the Late Jinningean stage, the Late Caledonianstage, and the Late Indosinian-Late Yanshanian stage) under the control of tw0 tectonic units(geosyncline and diwa). (3) Three endogenic meta1logenic epoches accompanying the three stagesof ore-related granitic magmatism. (4) One major metallogenic epoch characterized by concentrat-ed commercial metallizations in large scale related to the Yanshanian crust-derived type granites.Tectonically,this major metallogenic epoch is exactly consistent with the stage of violent diwa ac-tivity. This is by no means fortuitous, but is the unavoidable result of the development and evolu-tion of the objective geologic history.展开更多
Biological soil crusts(BSCs) are the important components of alpine meadow ecosystems.The extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing pressure.There is signifi...Biological soil crusts(BSCs) are the important components of alpine meadow ecosystems.The extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing pressure.There is significant interest in impacts of crust composition on plant seed germination,especial l y in(semi-) arid environments.However,little is known about the influences of BSCs,and their associations with alpine meadow succession,on germination of typical alpine meadow vascular plant species.In a full factorial common-gardenexperiment,we studied effects of:(1) crust type,(2) seed position,and(3) surface texture on seed germination.We chose three typical alpine meadow plant species(i.e.Poa pratensis,Tibetia himalaica and Potentillen nivea),which belonged to different functional groups(graminoids,legumes,and forbs) and play important roles in all alpine meadow succession stages.Crust type and seed position influenced seed germination,and the inhibitory effects of BSCs depended on the crust type and seed species tested.The major factors influencing seed germination were BSC type,seed position,soil texture,and the interactions between BSC type and seed position; species and seed position; species andsurface texture; and species,crust type,and surface texture.Cyanobacteria crust significantly inhibited germination of all seeds.Seed position also had a significant effect on seed germination(p < 0.001).Fewer seedlings germinated on the surface than below the surface,this was especially true for P.nivea.seeds within cyanobacteria and lichen crusts.Only germination rates of T.himalaica on the soil surface were significantly correlated with plant occurrence frequency within the alpine meadow community.The poor correlation for the other two species is possibly that they are perennials.Our results clearly demonstrated that BSCs can be biological filters during seed germination,depending on the BSC succession stage.Through their influences on seed germination,BSCs can strongly influence community assemblages throughout alpine meadow retrogressive succession.展开更多
Evidences for the existence of ferromanganese crust boundary were found for the first time during the survey of the “DA YANG YI HAO” Vessel 2003. Some typical characteristics of the boundary are summarized and the s...Evidences for the existence of ferromanganese crust boundary were found for the first time during the survey of the “DA YANG YI HAO” Vessel 2003. Some typical characteristics of the boundary are summarized and the significances of the finding of the boundary are included in the genesis discussion. Ore prospecting and assessment of the crust resources are described in this paper. The morphologic and extending characteristics of the crust boundary led to the recognition of two types of crust boundary： interpenetration crust boundary and closed crust boundary. According to the distribution and types of the crust, however, the boundaries are classified into three types： the boundary between ferromanganese crust and detrital sediment, the boundary between tabular crust and seamount nodules, and the boundary between tabular crust and rudaceous crust. This study revealed that the boundary between tabular crust and nodules was not formed under different regional environments but formed under different nucleation potential barriers between different initial growth （nucleation and germination） processes and between solid rocks and loose sediments. The rudaceous crusts are controlled spatially by fracture zones and the crusts＇ boundaries are controlled by the seamount structure and landform. The discovery of the crust boundaries reveals the crust＇s ‘negative growth’ phenomena （especially for some seamount nodules）. The boundary investigation can be helpful in identifying the existence of tabular crust covered by detrital sediments and in calculating the area covered by the crust. The resource calculation error and the resource quality as well as resource exploration degree can be assessed through the survey of crust boundary.展开更多
Red clay type gold deposits,located in the south of China,are situated not only in orogenic belts,but also in inner cratons,where climate is tropical-subtropical with clear arid and humid.The lateritic weathering crus...Red clay type gold deposits,located in the south of China,are situated not only in orogenic belts,but also in inner cratons,where climate is tropical-subtropical with clear arid and humid.The lateritic weathering crust often can be divided into five zones,including topsoil,siliceous duricrust zone,multi-color zone(or red clay zone in some deposits),pallid zone and saprolite zone from surface to the base rock,several of which are absent in some deposits.The base rocks are composed mainly of carbonate rocks with minor clastic rocks,intermediate-basic volcanic rocks and intermediate-acid and alkalic intrusions.The orebodies are mainly located in the multi-color zone with part of them in the pallid and saprolite zones.The ore sources include orebodies of Carlin-type gold deposits and porphyry gold deposits,as well as gold-rich base rocks.The red clay type gold deposits experienced early-stage endogenic gold mineralization and laterization during the Tertiary and Quaternary.The areas with endogenic gold deposits,especially Carlin-type gold deposits and porphyry gold deposits in karst depressions on the plateau,structual erosional platforms in the middle-lower mountains,and intermountain basins in southern China are well worth studying to trace red clay type gold deposits.展开更多
Interesting classifications of basinogenesis and basins were proposed by many scientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamic angle . I...Interesting classifications of basinogenesis and basins were proposed by many scientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamic angle . In order to more comprehensively understand them for more effectively guiding prospecting and exploration, the author integrates the two methods of analysis with each other and proposes an integrative classification .According to the historical - dynamic integrative classification,basinogenesis and basins can be.di-vided into three types :oceanic crust type ,embryo-continental (transitional )crust type and continental crust type .Oceanic crust type can be subdivided into mobile region type (mainly tenskmal )and stable region type . Embryo-continental type includes pre-geosynclinal type (divisible into several mobile region types and stable region types with tensional type predominating among mobile region types ) and ear ly-geosynclinal type (mainly tenskmal ) .Continental crust type includes late- geosynclinal (fold belt)type (compressional or tenskmal ),platform type (mainly sinking and rarely tenskmal subsidence-aulacogen)and geodepression (diwa )type (compressional , tenskmal or compresskmal-tenskmal ).展开更多
基金This paperis supported bythe Pilot Project of the Knowledge InnovationProgramof Chinese Academy of Sciences (No . KZCX3-SW-223) theNational Natural Science Foundation of China ( Nos . 40506016 and40576032) .
文摘We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series chronological studies, analysis of major and minor elements performed by X-ray fluorescence spectrometry （XRF） and inductively coupled plasma-mass spectrometer （ICPMS）, three major accretion periods and corresponding paleocnvironments can be ascertained. The first period is a faster accretion period in the terminal Late Miocene to the Early Pliocene with looser structure and higher volcanic detritus content, corresponding to the active Antarctic bottom waters and depressed temperature from the intermediate Middle Miocene to the Early Pliocene. The second period is a pulse of pelagic clay deposition at the Early to Middle Pliocene, reflecting the shrinkage of the Antarctic bottom waters and the global temperature elevation of this period. The third period is a slower accretion period from the Middle Pliocene, which indicates the more violent activity of Antarctic bottom waters once again and more depressed temperature than the first period, facilitating the accretion of a more compact and pure ferromanganese zone. The paleoceanographic histories of these studied areas had not been made clear in previous research.
文摘In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-derived type granitoids can be generalized as follows: (1) Two suites ofsource strata for Magmatism-the Pre-Sinian and the Lower Sinianl here the unity of the old foldbasement, the source strata for magmatism and the source strata for metallization are particularlyhighlighted. (2) Multi-stage melting of source strata for magmatism resulting in the formation ofmajor ore-related granites of three different stages (the Late Jinningean stage, the Late Caledonianstage, and the Late Indosinian-Late Yanshanian stage) under the control of tw0 tectonic units(geosyncline and diwa). (3) Three endogenic meta1logenic epoches accompanying the three stagesof ore-related granitic magmatism. (4) One major metallogenic epoch characterized by concentrat-ed commercial metallizations in large scale related to the Yanshanian crust-derived type granites.Tectonically,this major metallogenic epoch is exactly consistent with the stage of violent diwa ac-tivity. This is by no means fortuitous, but is the unavoidable result of the development and evolu-tion of the objective geologic history.
基金funded by the Chinese National Natural Scientific Foundation(Grant No.31270576)by the grant(Grant No.2016-ZJ-710)from Qinghai Province and Key laboratory of crop molecular breeding of Qinghai Province
文摘Biological soil crusts(BSCs) are the important components of alpine meadow ecosystems.The extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing pressure.There is significant interest in impacts of crust composition on plant seed germination,especial l y in(semi-) arid environments.However,little is known about the influences of BSCs,and their associations with alpine meadow succession,on germination of typical alpine meadow vascular plant species.In a full factorial common-gardenexperiment,we studied effects of:(1) crust type,(2) seed position,and(3) surface texture on seed germination.We chose three typical alpine meadow plant species(i.e.Poa pratensis,Tibetia himalaica and Potentillen nivea),which belonged to different functional groups(graminoids,legumes,and forbs) and play important roles in all alpine meadow succession stages.Crust type and seed position influenced seed germination,and the inhibitory effects of BSCs depended on the crust type and seed species tested.The major factors influencing seed germination were BSC type,seed position,soil texture,and the interactions between BSC type and seed position; species and seed position; species andsurface texture; and species,crust type,and surface texture.Cyanobacteria crust significantly inhibited germination of all seeds.Seed position also had a significant effect on seed germination(p < 0.001).Fewer seedlings germinated on the surface than below the surface,this was especially true for P.nivea.seeds within cyanobacteria and lichen crusts.Only germination rates of T.himalaica on the soil surface were significantly correlated with plant occurrence frequency within the alpine meadow community.The poor correlation for the other two species is possibly that they are perennials.Our results clearly demonstrated that BSCs can be biological filters during seed germination,depending on the BSC succession stage.Through their influences on seed germination,BSCs can strongly influence community assemblages throughout alpine meadow retrogressive succession.
基金Project supported by the National Natural Science Foundation of China (No. 49976017), and the China Ocean Mineral Resources R & D Association (COMAR) (No. DY105-01-01-01) and the National Basic Research Program (973) of China (No. G2000046700)
文摘Evidences for the existence of ferromanganese crust boundary were found for the first time during the survey of the “DA YANG YI HAO” Vessel 2003. Some typical characteristics of the boundary are summarized and the significances of the finding of the boundary are included in the genesis discussion. Ore prospecting and assessment of the crust resources are described in this paper. The morphologic and extending characteristics of the crust boundary led to the recognition of two types of crust boundary： interpenetration crust boundary and closed crust boundary. According to the distribution and types of the crust, however, the boundaries are classified into three types： the boundary between ferromanganese crust and detrital sediment, the boundary between tabular crust and seamount nodules, and the boundary between tabular crust and rudaceous crust. This study revealed that the boundary between tabular crust and nodules was not formed under different regional environments but formed under different nucleation potential barriers between different initial growth （nucleation and germination） processes and between solid rocks and loose sediments. The rudaceous crusts are controlled spatially by fracture zones and the crusts＇ boundaries are controlled by the seamount structure and landform. The discovery of the crust boundaries reveals the crust＇s ‘negative growth’ phenomena （especially for some seamount nodules）. The boundary investigation can be helpful in identifying the existence of tabular crust covered by detrital sediments and in calculating the area covered by the crust. The resource calculation error and the resource quality as well as resource exploration degree can be assessed through the survey of crust boundary.
基金supported by the National Basic Research Program of China(973 Program)(No. 2009CB421008)111 Project(No.B07011)Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)
文摘Red clay type gold deposits,located in the south of China,are situated not only in orogenic belts,but also in inner cratons,where climate is tropical-subtropical with clear arid and humid.The lateritic weathering crust often can be divided into five zones,including topsoil,siliceous duricrust zone,multi-color zone(or red clay zone in some deposits),pallid zone and saprolite zone from surface to the base rock,several of which are absent in some deposits.The base rocks are composed mainly of carbonate rocks with minor clastic rocks,intermediate-basic volcanic rocks and intermediate-acid and alkalic intrusions.The orebodies are mainly located in the multi-color zone with part of them in the pallid and saprolite zones.The ore sources include orebodies of Carlin-type gold deposits and porphyry gold deposits,as well as gold-rich base rocks.The red clay type gold deposits experienced early-stage endogenic gold mineralization and laterization during the Tertiary and Quaternary.The areas with endogenic gold deposits,especially Carlin-type gold deposits and porphyry gold deposits in karst depressions on the plateau,structual erosional platforms in the middle-lower mountains,and intermountain basins in southern China are well worth studying to trace red clay type gold deposits.
文摘Interesting classifications of basinogenesis and basins were proposed by many scientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamic angle . In order to more comprehensively understand them for more effectively guiding prospecting and exploration, the author integrates the two methods of analysis with each other and proposes an integrative classification .According to the historical - dynamic integrative classification,basinogenesis and basins can be.di-vided into three types :oceanic crust type ,embryo-continental (transitional )crust type and continental crust type .Oceanic crust type can be subdivided into mobile region type (mainly tenskmal )and stable region type . Embryo-continental type includes pre-geosynclinal type (divisible into several mobile region types and stable region types with tensional type predominating among mobile region types ) and ear ly-geosynclinal type (mainly tenskmal ) .Continental crust type includes late- geosynclinal (fold belt)type (compressional or tenskmal ),platform type (mainly sinking and rarely tenskmal subsidence-aulacogen)and geodepression (diwa )type (compressional , tenskmal or compresskmal-tenskmal ).
