Neogene weathering and supergene manganese enrichment in subtropical South China: An 40Ar/39Ar approach and paleoclimatic significance
Neogene weathering and supergene manganese enrichment in subtropical South China: An 40Ar/39Ar approach and paleoclimatic significance
复制标题
华南亚热带新近纪风化与表生锰富集：40Ar/39Ar方法及其古气候意义
DOI：
10.1016/j.epsl.2007.01.021
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发表时间：
2007-04
影响因子：
5.3
通讯作者：
中科院分区：
文献类型：
--
作者：
深部风化剖面及其伴生的表生锰氧化物矿床在我国南方分布广泛。然而，他们的年龄数据是不可用的，直到最近。40 Ar/39 Ar激光增量加热分析的含钾表生锰氧化物收集从四个风化剖面在钦州防城锰带，广西省，中国南部，提供了，第一次，风化和表生锰富集的时间上的数值约束。42颗隐钾矿中有38颗获得了明确的坪年龄（36颗）或假坪年龄（2颗），年龄范围为17.6±0.5 ~ 4.71± 0.08Ma（2σ）。结果，结合数据从相邻的广东省和湖南省的锰氧化物矿床，文件的长期历史的风化和表生锰富集，从最早的中新世到最晚的上新世在华南地区跨越。这表明整个新近纪华南地区气候温暖湿润，有利于强烈风化和次生成矿作用的发生。风化年代学推断的气候条件与华南新生代内陆盆地和边缘海盆的沉积记录和植物群、动物群化石相一致。风化年代学数据还提供了东亚季风的启动和加强的时间限制，一直是华南潮湿气候的原因。
Deep weathering profiles and associated supergene Mn-oxides deposits are widely distributed in South China. However, data on their ages are not available until most recently.40Ar/39Ar laser incremental heating analysis of potassium-bearing supergene Mn-oxides collected from four weathering profiles in the Qinzhou–Fangcheng Mn belt, Guangxi Province, South China, provides, for the first time, numerical constraints on timing of weathering and supergene Mn enrichment. Thirty-eight of 42 cryptomelane grains yield well-defined plateau (36 grains) or pseudo plateau (2 grains) ages ranging from 17.6±0.5 Ma to 4.71±0.08 Ma (2σ). The results, when combined with data from Mn-oxides deposits from the adjacent Guangdong and Hunan Provinces, document a protracted history of weathering and supergene Mn enrichment, spanning from the earliest Miocene to the latest Pliocene in South China. This indicates that warm and humid climatic conditions conducive to intense weathering and secondary mineralization prevailed across South China during the whole Neogene. The climatic conditions inferred from weathering geochronology are consistent with sedimentary records and fossil floral and fauna associations from Cenozoic inland and marginal sea basins of South China. The weathering geochronology data also provide temporal constraints on the initiation and intensification of the East Asian monsoon that has been the cause for the South China's humid climate.
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影响因子：
3.9
作者：
C. Spier;P. Vasconcelos;Sonia M.B. Oliviera
通讯作者：
C. Spier;P. Vasconcelos;Sonia M.B. Oliviera
影响因子：
5
作者：
G. Ruffet;C. Innocent;A. Michard;G. Féraud;A. Beauvais;D. Nahon;B. Hamelin
通讯作者：
G. Ruffet;C. Innocent;A. Michard;G. Féraud;A. Beauvais;D. Nahon;B. Hamelin
DOI：
10.5382/rev.12.04
发表时间：
1999
期刊：
--
影响因子：
--
作者：
P. Vasconcelos
通讯作者：
P. Vasconcelos
影响因子：
5.3
作者：
STEIGER, RH;JAGER, E
通讯作者：
JAGER, E
DOI：
10.1146/annurev.earth.27.1.183
发表时间：
1999
期刊：
--
影响因子：
--
作者：
P. Vasconcelos
通讯作者：
P. Vasconcelos