Palaeoclimatic and hydrological environments inferred by moisture indexes from the S4 palaeosol section in the Xi'an region, China

Early–Middle Pleistocene Magnetostratigraphic and Rock Magnetic Records of the Dolynske Section (Lower Danube, Ukraine) and Their Application to the Correlation of Loess–Palaeosol Sequences in Eastern and South-Eastern Europe

“…There has been significant focus on the implementation of new research methods within a multidisciplinary approach to search for new complete sections within the terrestrial archives, and to analyse the factors that have caused palaeoenvironmetal changes [100][101][102][103][104][105][106][107][108][109][110][111][112][113][114][115][116][117][118][119].…”

Causes of surface sediments and natural environment of Tongwan city in Jingbian county of Shaanxi province during its construction period

“…自 然 资 源 学 报 距今已有 1600 年历史。统万城所在的靖边县地处 108°17′15″~109°20′15″E、36°58′45″~38°0 3′15″N，海拔在 1123~1823 m 之间。靖边县属半干旱大陆性季风气候，光照充足，温差 大，气候干燥，雨热同季，四季分明。该区生态环境脆弱 [18] ，易于发生沙漠化。年平均 气温 7.8 ℃，≥10 ℃的植物生长有效积温为 2800 ℃，年平均无霜期为 130 天，年平均降 水量 395.4 mm [19] 5 cm 含量接近 10%，5 cm 之下的深厚沙层含量低于 3% [20] 。腾格里沙漠的风成沙沉积中 几乎不含粗砂 [21] 。在毛乌素沙地南缘，现代沙丘沙中以细砂和中砂为主，粗砂仅为3.2% [22] 。 学组成为α-FeO(OH) [24] 。由于非结晶的针铁矿在水中以不可溶胶体形式存在，常与铁锰结 图 5 统万城 6 个剖面粒度含量变化 核相伴出现 [24,25] ，所以它的形成需要饱和的水分条件。针铁矿对沉积物成因和沉积环境具 有重要指示作用，其代表的沙层成因类型和沉积环境将在后述讨论。…”