在长江河口两翼广泛分布第一硬土层(FHSL),研究其形成机制及工程地质特性对工程建设具有很好的指导意义。根据调查资料(钻孔935个,累计进尺42128 m)和试验资料,首次精确确认了长江河口北翼第一硬土层分布界线,研究了第一硬土层的形成年...在长江河口两翼广泛分布第一硬土层(FHSL),研究其形成机制及工程地质特性对工程建设具有很好的指导意义。根据调查资料(钻孔935个,累计进尺42128 m)和试验资料,首次精确确认了长江河口北翼第一硬土层分布界线,研究了第一硬土层的形成年代、粒度特征、地球化学特征、工程地质特性等。研究表明:第一硬土层形成年龄为20~11 ka B.P.(多个光释光和14C测年资料);硬土层含水率随深度的增加有增大的趋势,表明气候自下向上逐渐变凉和变干;第一硬土层的颗粒级配、粒度分布频率曲线、C-M沉积图等特征显示,第一硬土层主要由粉砂、极细砂和粘土粒级组成,样品的粒度频率曲线主要呈单峰分布,反映出物质沉积前所受搬运营力性质单一,土体颗粒沉积以均匀悬浮占绝对优势,沉积环境是一种相对稳定的低能环境。第一硬土层的发育受气候控制,大致可以分为3个阶段:第1阶段(20~15 ka B.P.)为沉积与成土交替作用时期,且以沉积作用为主,硬土层剖面厚度主要受该阶段控制,至末次盛冰期结束;第2阶段(15~11 ka B.P.)为暴露成土期,这时洪水不能形成越岸沉积,加积作用基本停止,硬土层厚度不再明显增加,已形成的第一硬土区域受到频繁变迁的分合河网的侵蚀切割,形成多条不规则古河道和台地,硬土层逐渐脱水成陆,经历了风化成壤的过程;第3阶段(11 ka B.P.至今)为淹埋期,随着全新世的到来,气候变暖,海平面不断上升,硬土层被其上覆的海相沉积层掩埋,成岩作用开始直到现今。土体易溶盐含量较高,为典型氯盐渍土类型,自下而上具有从低变高的趋势,为海相层覆盖硬土层以后成岩过程造成的。展开更多
In this report, we reviewed the differences in the ecosystem services of coastal and inland areas surrounding 39 Sake breweries in Chiba Prefecture by investigating environmental variables (e.g., location, altitude, s...In this report, we reviewed the differences in the ecosystem services of coastal and inland areas surrounding 39 Sake breweries in Chiba Prefecture by investigating environmental variables (e.g., location, altitude, soil, and hardness of preparation water). The Sake breweries were located in three distinct environments: the coastal vicinity, the river plains region, and the plateau/ mountainous region. The hardness of the preparation water and the soil types in the coastal vicinity were compared with those of the river plains and the plateau/mountainous region. Strong hard and hard water sources were observed in 70% or more of the breweries in the coastal vicinity, and sand dune regosol, coarse particle brown lowland soil, and coarse particle grey soil were more prevalent along the coast than inland. Most of the Sake brewery wells in the coastal vicinity were approximately 5 - 10 munderground, and there were no great differences in the number of Sake breweries in each well depth class in the river plains and the plateau/mountains region. We analysed environmental factors (distance from the sea, soil type, water hardness and preparation water collection depth) using a principal component analysis. This analysis revealed the existence of three main environments: the coastal vicinity, the river plains and the plateau/mountainous region. We conclude that the decrease in altitude between the inland Sake breweries and those along the coast is accompanied by a corresponding increase in the hardness of preparation water (from soft water to strong hard or hard water) and shifts in soil composition from gley soil, grey lowland soil, brown forest soil, and andosol to sand dune regosol, coarse particle brown lowland soil, and coarse particle grey soil.展开更多
文摘在长江河口两翼广泛分布第一硬土层(FHSL),研究其形成机制及工程地质特性对工程建设具有很好的指导意义。根据调查资料(钻孔935个,累计进尺42128 m)和试验资料,首次精确确认了长江河口北翼第一硬土层分布界线,研究了第一硬土层的形成年代、粒度特征、地球化学特征、工程地质特性等。研究表明:第一硬土层形成年龄为20~11 ka B.P.(多个光释光和14C测年资料);硬土层含水率随深度的增加有增大的趋势,表明气候自下向上逐渐变凉和变干;第一硬土层的颗粒级配、粒度分布频率曲线、C-M沉积图等特征显示,第一硬土层主要由粉砂、极细砂和粘土粒级组成,样品的粒度频率曲线主要呈单峰分布,反映出物质沉积前所受搬运营力性质单一,土体颗粒沉积以均匀悬浮占绝对优势,沉积环境是一种相对稳定的低能环境。第一硬土层的发育受气候控制,大致可以分为3个阶段:第1阶段(20~15 ka B.P.)为沉积与成土交替作用时期,且以沉积作用为主,硬土层剖面厚度主要受该阶段控制,至末次盛冰期结束;第2阶段(15~11 ka B.P.)为暴露成土期,这时洪水不能形成越岸沉积,加积作用基本停止,硬土层厚度不再明显增加,已形成的第一硬土区域受到频繁变迁的分合河网的侵蚀切割,形成多条不规则古河道和台地,硬土层逐渐脱水成陆,经历了风化成壤的过程;第3阶段(11 ka B.P.至今)为淹埋期,随着全新世的到来,气候变暖,海平面不断上升,硬土层被其上覆的海相沉积层掩埋,成岩作用开始直到现今。土体易溶盐含量较高,为典型氯盐渍土类型,自下而上具有从低变高的趋势,为海相层覆盖硬土层以后成岩过程造成的。
文摘In this report, we reviewed the differences in the ecosystem services of coastal and inland areas surrounding 39 Sake breweries in Chiba Prefecture by investigating environmental variables (e.g., location, altitude, soil, and hardness of preparation water). The Sake breweries were located in three distinct environments: the coastal vicinity, the river plains region, and the plateau/ mountainous region. The hardness of the preparation water and the soil types in the coastal vicinity were compared with those of the river plains and the plateau/mountainous region. Strong hard and hard water sources were observed in 70% or more of the breweries in the coastal vicinity, and sand dune regosol, coarse particle brown lowland soil, and coarse particle grey soil were more prevalent along the coast than inland. Most of the Sake brewery wells in the coastal vicinity were approximately 5 - 10 munderground, and there were no great differences in the number of Sake breweries in each well depth class in the river plains and the plateau/mountains region. We analysed environmental factors (distance from the sea, soil type, water hardness and preparation water collection depth) using a principal component analysis. This analysis revealed the existence of three main environments: the coastal vicinity, the river plains and the plateau/mountainous region. We conclude that the decrease in altitude between the inland Sake breweries and those along the coast is accompanied by a corresponding increase in the hardness of preparation water (from soft water to strong hard or hard water) and shifts in soil composition from gley soil, grey lowland soil, brown forest soil, and andosol to sand dune regosol, coarse particle brown lowland soil, and coarse particle grey soil.
