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
In this paper the differences and characteristics of the degree of seismic activities of various tectonic blocks and the different parts within the blocks in the eastern part of the Chinese mainland (to the east of 10...In this paper the differences and characteristics of the degree of seismic activities of various tectonic blocks and the different parts within the blocks in the eastern part of the Chinese mainland (to the east of 105°E) have been studied. Based on the results, the crust-mantle structural factors which caused these differences have further been studied from the inner and deep part of the plate. The ratio between the crustal and lithospheric thicknesses, i. e. the so-called crust-mantle structural ratio R, has been calculated. The result has shown that the magnitude of R has a close relation to the degree of seismic activity. The R-value implies the state of the movement of crust-mantle materials and the degree of interaction between the crust and mantle through convection and intrusion.展开更多
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.
文摘In this paper the differences and characteristics of the degree of seismic activities of various tectonic blocks and the different parts within the blocks in the eastern part of the Chinese mainland (to the east of 105°E) have been studied. Based on the results, the crust-mantle structural factors which caused these differences have further been studied from the inner and deep part of the plate. The ratio between the crustal and lithospheric thicknesses, i. e. the so-called crust-mantle structural ratio R, has been calculated. The result has shown that the magnitude of R has a close relation to the degree of seismic activity. The R-value implies the state of the movement of crust-mantle materials and the degree of interaction between the crust and mantle through convection and intrusion.
