沉积物干容重分析及其沉积学意义: 以东海内陆架海区为例

Dry bulk density is often applied to calculate the flux as an important parameter, which has a great significance to understand sediment budget, source-sink fluxes, and geomorphologic evolutions. However, the test and analysis procedures of the previous studies on dry bulk density were lack of uniform norms and not taken seriously. In this paper, dry bulk density of surface sediments and core sediments from the inner shelf of the East China Sea was obtained by means of experimental test and indirect formula calculation. The accuracy of two methods was compared and analyzed to enhance the quantitation and accuracy in sedimentary research. The general value of dry bulk density was determined to be 1.1-1.5g/cm³ for fine particulate matter sediments in the inner shelf of the East China Sea. The main factors affecting dry bulk density were the mineral composition and grain size of the sediments. The former affected by the density of mineral compositions, while the latter affected the porosity. Therefore, the test of dry bulk density should be completed as soon as possible after sampling. In order to accurately estimate the sediment flux, appropriate dry bulk density should be calculated based on the spatial variation of the main grain size and the porosity of sediments.