The last twenty-five years of geological investigation of the Mediterranean region have disproved the traditional notion that the Alpine-Himalayan mountain ranges originated from the closure of a single, albeit comple...The last twenty-five years of geological investigation of the Mediterranean region have disproved the traditional notion that the Alpine-Himalayan mountain ranges originated from the closure of a single, albeit complex,oceanic domain-the Tethys. Instead, the present-day geological configuration of the Mediterranean region is the result of the creation and ensuing consumption of two major oceanic basins-the Paleotethys and the Neotethys-and of additional smaller oceanic basins within an overall regime of prolonged interaction between the Eurasian and the African-Arabian plates.In greater detail, there is still some debate about exactly what Tethys existed at what time. A consensus exists as to the presence of (i) a mainly Paleozoic paleotethyan ocean north of the Cimmerian continent(s); (ii) a younger late Paleozoic-Mesozoic neotethyan ocean located south of this continent, and finally ; ( iii ) a middle Jurassic ocean, the Alpine Tethys-Valais, an extension of the central Atlantic ocean in the western Tethyan domain. Additional late Paleozoic to Mesozoic back-arc marginal basins along the active Eurasian margin com-plicated somewhat this simple picture. The closure of these heterogeneous oceanic domains produced a sys-tem of connected yet discrete orogenic belts which vary in terms of timing, tectonic setting and internal archi-tecture, and cannot be interpreted as the end product of a single "Alpine" orogenic cycle.In Neogene time. following prolonged indentation along the Alpine front, a number of small continental microterranes (Kabylies, Balearic Islands, Sardinia-Cor-sica, Calabria) rifted off the Eurooean-lberian continan-tal margin and drifted toward south or southeast, leaving in their wake areas of thinned continental crust (e.g.Valencia Trough) or small oceanic basins (Algerian,Provencal and Tyrrhenian basins). The E Mediterranean is similarly characterized by widespread Neogene exten-sional tectonism, as indicated by thinning of continental crust along low-angle detachment faults in the Aegean Sea and the periaegean regions. Overall, Neogene exten-sion in the Mediterranean can be explained as the result of roll-back of the N-dipping subducting slab along the lonian-E Mediterranean subduction zones. The complex Neogene geologic scenario of the Mediterranean is com-plicated further by the deposition of widespread evapor-ites during Messinian (late Miocene) time.展开更多
Based on the results of multipurpose regional geochemical surveys of the Guizhou Province, geochemical characteristics of soil Se and Se-rich land resources in the central area of Guiyang City were studied and evaluat...Based on the results of multipurpose regional geochemical surveys of the Guizhou Province, geochemical characteristics of soil Se and Se-rich land resources in the central area of Guiyang City were studied and evaluated.Major conclusions are as follows:(1) the Se content in surface soil of the central area of Guiyang City was 0.17–2.89 mg kg^(-1), and the average was 0.78 mg kg^(-1), which were respectively 2.6 and 3.9 times of the national background value of soil and the world background value of soil.The Se content in deep soil was 0.11–1.48 mg kg^(-1), and the average was 0.44 mg kg^(-1), which were respectively 1.5 and2.2 times of the national background value of soil and the world background value of soil. The soil Se content decreased with the increase in the soil depth on the vertical profile, and the surface soil had a higher Se content.(2)Distribution of Se content was mainly affected by parent material, physicochemical properties of soil and other components, soil type, and land use type. Parent material played a key role, as the soil Se content was mainly originated from parent rock and increased with the background value of Se in parent rock, physicochemical properties of soil and other components had certain influences upon the Se content. Se was shown to have a significant linear positive correlation with S and organic carbon but no significant correlation with p H value. Se content varied with different types of soil as follows: skeleton soil > yellow soil > paddy soil > limestone soil > purple soil. Land use type also hadcertain influences upon the soil Se content as follows: dry land > construction land > garden plot > grassland =garden plot > forest land.(3) Taking 0.4 mg kg^(-1)B x(Se) <3.0 mg kg^(-1) as the standard for Se-rich soil, Se-rich soil of the study area covered an area of 2224 km^2 and 92.5% of the total area; the remaining is general soil. The study area had no Se-excess soil. Therefore, the central area of Guiyang City has a high proportion of Se-rich land, a large area of Serich land resources, and a moderate selenium enrichment strength, which have been rarely seen anywhere and provide advantageous resources for the development of Se-rich featured agriculture.展开更多
Research on selection of superior breeding infraspecies Gyrinops versteegii (Gilg) Domke aims to select an infraspecies of G. versteegii having internal factors that affect the quality and quantity of production aro...Research on selection of superior breeding infraspecies Gyrinops versteegii (Gilg) Domke aims to select an infraspecies of G. versteegii having internal factors that affect the quality and quantity of production aromatic resin or agarwood. The internal factors are variations in wood anatomy, phytochemicals and agarwood of infraspecies G. versteegii. Of five local populations taken from West Lombok Island in Indonesia, the research areas are geographically located at coordinates: 8°15′-8°40′ South Latitude and 116°00′-116°20′East Longitude. Quality and quantity of agarwood production is influenced by internal factors of eaglewood trees, such as high starch production and the size of the cells making up the larger wood tissue. Infraspecies G. versteegii that have quality and quantity production of aromatic resin (the best agarwood) is Beringin group and the highest quantity of agarwood production (agarwood formation on the whole organ) is Soyun group.展开更多
文摘The last twenty-five years of geological investigation of the Mediterranean region have disproved the traditional notion that the Alpine-Himalayan mountain ranges originated from the closure of a single, albeit complex,oceanic domain-the Tethys. Instead, the present-day geological configuration of the Mediterranean region is the result of the creation and ensuing consumption of two major oceanic basins-the Paleotethys and the Neotethys-and of additional smaller oceanic basins within an overall regime of prolonged interaction between the Eurasian and the African-Arabian plates.In greater detail, there is still some debate about exactly what Tethys existed at what time. A consensus exists as to the presence of (i) a mainly Paleozoic paleotethyan ocean north of the Cimmerian continent(s); (ii) a younger late Paleozoic-Mesozoic neotethyan ocean located south of this continent, and finally ; ( iii ) a middle Jurassic ocean, the Alpine Tethys-Valais, an extension of the central Atlantic ocean in the western Tethyan domain. Additional late Paleozoic to Mesozoic back-arc marginal basins along the active Eurasian margin com-plicated somewhat this simple picture. The closure of these heterogeneous oceanic domains produced a sys-tem of connected yet discrete orogenic belts which vary in terms of timing, tectonic setting and internal archi-tecture, and cannot be interpreted as the end product of a single "Alpine" orogenic cycle.In Neogene time. following prolonged indentation along the Alpine front, a number of small continental microterranes (Kabylies, Balearic Islands, Sardinia-Cor-sica, Calabria) rifted off the Eurooean-lberian continan-tal margin and drifted toward south or southeast, leaving in their wake areas of thinned continental crust (e.g.Valencia Trough) or small oceanic basins (Algerian,Provencal and Tyrrhenian basins). The E Mediterranean is similarly characterized by widespread Neogene exten-sional tectonism, as indicated by thinning of continental crust along low-angle detachment faults in the Aegean Sea and the periaegean regions. Overall, Neogene exten-sion in the Mediterranean can be explained as the result of roll-back of the N-dipping subducting slab along the lonian-E Mediterranean subduction zones. The complex Neogene geologic scenario of the Mediterranean is com-plicated further by the deposition of widespread evapor-ites during Messinian (late Miocene) time.
基金supported by outstanding science and technology education personnel special funds of Guizhou Province (Specific words in Guizhou Province (2012)No.27)National multipurpose regional geochemical survey Project (GZTR20070110)
文摘Based on the results of multipurpose regional geochemical surveys of the Guizhou Province, geochemical characteristics of soil Se and Se-rich land resources in the central area of Guiyang City were studied and evaluated.Major conclusions are as follows:(1) the Se content in surface soil of the central area of Guiyang City was 0.17–2.89 mg kg^(-1), and the average was 0.78 mg kg^(-1), which were respectively 2.6 and 3.9 times of the national background value of soil and the world background value of soil.The Se content in deep soil was 0.11–1.48 mg kg^(-1), and the average was 0.44 mg kg^(-1), which were respectively 1.5 and2.2 times of the national background value of soil and the world background value of soil. The soil Se content decreased with the increase in the soil depth on the vertical profile, and the surface soil had a higher Se content.(2)Distribution of Se content was mainly affected by parent material, physicochemical properties of soil and other components, soil type, and land use type. Parent material played a key role, as the soil Se content was mainly originated from parent rock and increased with the background value of Se in parent rock, physicochemical properties of soil and other components had certain influences upon the Se content. Se was shown to have a significant linear positive correlation with S and organic carbon but no significant correlation with p H value. Se content varied with different types of soil as follows: skeleton soil > yellow soil > paddy soil > limestone soil > purple soil. Land use type also hadcertain influences upon the soil Se content as follows: dry land > construction land > garden plot > grassland =garden plot > forest land.(3) Taking 0.4 mg kg^(-1)B x(Se) <3.0 mg kg^(-1) as the standard for Se-rich soil, Se-rich soil of the study area covered an area of 2224 km^2 and 92.5% of the total area; the remaining is general soil. The study area had no Se-excess soil. Therefore, the central area of Guiyang City has a high proportion of Se-rich land, a large area of Serich land resources, and a moderate selenium enrichment strength, which have been rarely seen anywhere and provide advantageous resources for the development of Se-rich featured agriculture.
文摘Research on selection of superior breeding infraspecies Gyrinops versteegii (Gilg) Domke aims to select an infraspecies of G. versteegii having internal factors that affect the quality and quantity of production aromatic resin or agarwood. The internal factors are variations in wood anatomy, phytochemicals and agarwood of infraspecies G. versteegii. Of five local populations taken from West Lombok Island in Indonesia, the research areas are geographically located at coordinates: 8°15′-8°40′ South Latitude and 116°00′-116°20′East Longitude. Quality and quantity of agarwood production is influenced by internal factors of eaglewood trees, such as high starch production and the size of the cells making up the larger wood tissue. Infraspecies G. versteegii that have quality and quantity production of aromatic resin (the best agarwood) is Beringin group and the highest quantity of agarwood production (agarwood formation on the whole organ) is Soyun group.