Loess and Eolian Dust in the East Asia

晚更新世以来，从亚洲大陆输送来的长距离对流层风尘沉积在日本和韩国的陆地表面以及日本海和北太平洋的海底。日本海沿着地区发育在石灰岩、玄武岩等不同母质上的非脲基化的红砂土和埋藏在古沙丘中的古土壤受亚洲大陆风尘的强烈影响，风尘的特征是以直径0.7 ~ 30 μ m的土粒为主。塔克拉玛干河沉积物的中值粒径为20 ~ 100 μ m。中国黄土、黄土衍生土、风成尘和远洋沉积物的中值粒径从中国东部经日本和朝鲜（3- 30 μ m）到夏威夷和北太平洋（0.7-8 μ m）稳步减小。其主要矿物为2：1和2：1：1层状硅酸盐、高岭石、石英和长石，具有较高的K20/SiO2和SiO2/Al 2 O3摩尔比。日本、朝鲜和日本海的土壤和风成尘沉积物中细粒石英的氧同位素组成为14 ~ 17%，表明其为亚洲大陆成因。亚洲风成尘最近的通量约为4 ~ 7 mm/1000 yr，而晚更新世冰期约为14 ~ 23 mm/1000 yr，来自撒哈拉沙漠的以色列风成尘在Quaernary晚期以0.5 ~ 1 mm/年的平均速率积累。

Long range, tropospheric eolian dust transported from the Asian continents has been deposited on the land surfaces in Japan and Korea and on the sea floor of the Sea of Japan and the North Pacific Ocean since the late Pleistocene. Nonallophanic andosols, red yellow soils developed on limestones, basalts, and others diverse parent materials, and paleosols buried in paleodunes in the area along the coast of Japan Sea, were strongly influenced by the eolian dust derived from the Asian Continents.The eolian dust was characterized by a predominance of soil particles 0.7 to 30 mu m in diameter. The median particle diameters of wadi sediment in the Takla Makan ranged from 20 to 100 mu m. The median particle diameters of loess in China, loess derived soils, eolian dust, and pelagic sediments decrease steadily from the eastern part of China through Japan and Korea(3-30mum)to Hawaii and the north Pacific Ocean(0.7-8 mum). Their dominant minerals were 2 : 1 and 2 : 1 : 1 layer silicates, kaolinite, quartz, and feldspar, and were characterized by high K_20/SiO_2 and SiO_2/Al_2 0_3 molar ratios. Oxygen isotope compositions of fine grained quartz from soils and eolian dust deposits in Japan, Korea and the Japan Sea pelagic sediments ranged from 14 to 17%% indicating that it is of the Asian continental origin. The recent flux of Asian eolian dust is about 4 to 7 mm/1000 yrs. compared to about 14 to 23 mm/1000 yrs. in the late Pleistocene glacial periods.Israel eolian dust from the Saharan desert accumulated at an average rate of 0.5 to 1 mm/year in the late Quaernary.