The features of grain size distribution of microtektite-bearing layers are crucial, direct indicators to reflect the addition of impact dust into loess sediments.Because their sampling intervals were too large, previo...The features of grain size distribution of microtektite-bearing layers are crucial, direct indicators to reflect the addition of impact dust into loess sediments.Because their sampling intervals were too large, previous surveys could not reveal the contamination of the loess sediments by impact fallout (dust) in light of grain size distribution. Here, the authors present measurements for grain size distribution of loess samples taken around the microtektite-bearing layers at very dense sampling intervals.展开更多
Loess and paleosol have been regarded as an excellent geological body for reestablishment of the past 2.4 Ma paleoclimatic history.The discovery and study of microtektites in Luochuan loess section imply that the infl...Loess and paleosol have been regarded as an excellent geological body for reestablishment of the past 2.4 Ma paleoclimatic history.The discovery and study of microtektites in Luochuan loess section imply that the influence of impact event展开更多
Magnetic susceptibility (MS) value actually reflects component and contents of magnetic minerals.As a substitute indicator,MS is widely used for study on paleoclimatology recorded in loess and paleosol.Moreover,the MS...Magnetic susceptibility (MS) value actually reflects component and contents of magnetic minerals.As a substitute indicator,MS is widely used for study on paleoclimatology recorded in loess and paleosol.Moreover,the MS value of microtektite-bearing loess layers may expose contamination of the loess by abnormal展开更多
Anomalies of content of Ir, noble metals and other trace elements are usually regarded as crucial evidence of impact event. A large number of microtektites have been found in deep-sea sediments since the 1960s, but an...Anomalies of content of Ir, noble metals and other trace elements are usually regarded as crucial evidence of impact event. A large number of microtektites have been found in deep-sea sediments since the 1960s, but analyses of trace elements in microtektitebearing layers have seldom been reported, with the exception that Asaro et al. stated that microtektite-bearing layers in Caribbean Gulf exhibited anomaly of Ir (?). The展开更多
基金Project suppported by the National Natural Science Foundation of China.
文摘The features of grain size distribution of microtektite-bearing layers are crucial, direct indicators to reflect the addition of impact dust into loess sediments.Because their sampling intervals were too large, previous surveys could not reveal the contamination of the loess sediments by impact fallout (dust) in light of grain size distribution. Here, the authors present measurements for grain size distribution of loess samples taken around the microtektite-bearing layers at very dense sampling intervals.
基金Project supported by the National Natural Science Foundation of China.
文摘Loess and paleosol have been regarded as an excellent geological body for reestablishment of the past 2.4 Ma paleoclimatic history.The discovery and study of microtektites in Luochuan loess section imply that the influence of impact event
基金Project supported by the National Natural Science Foundation of China.
文摘Magnetic susceptibility (MS) value actually reflects component and contents of magnetic minerals.As a substitute indicator,MS is widely used for study on paleoclimatology recorded in loess and paleosol.Moreover,the MS value of microtektite-bearing loess layers may expose contamination of the loess by abnormal
基金Project supported by the National Natural Science Foundation of China
文摘Anomalies of content of Ir, noble metals and other trace elements are usually regarded as crucial evidence of impact event. A large number of microtektites have been found in deep-sea sediments since the 1960s, but analyses of trace elements in microtektitebearing layers have seldom been reported, with the exception that Asaro et al. stated that microtektite-bearing layers in Caribbean Gulf exhibited anomaly of Ir (?). The