Strontium and boron isotopic constraint on the marine origin of the Khammuane potash deposits in southeastern Laos
Strontium and boron isotopic constraint on the marine origin of the Khammuane potash deposits in southeastern Laos
复制标题
锶和硼同位素对老挝东南部 Khammuane 钾矿床海洋成因的约束
DOI：
10.1007/s11434-010-4010-x
复制
发表时间：
2010-10
影响因子：
--
通讯作者：
Xiao YingKai
中科院分区：
文献类型：
--
作者：
Tan HongBing;Ma HaiZhou;Li BinKai;Zhang XiYing;Xiao YingKai
2006年以来，我们对老挝东南部Khammuane地区进行了地质勘探。通过钻探 Thangon 组 (E1tg) 的古新世地层，发现了几个含有钾盐和光卤石的厚钾盐矿床序列。为了确定形成厚层盐矿床序列的卤水的来源，我们测量了钾盐矿床中一些盐矿物的锶和硼同位素组成。甘蒙钾盐矿床中石盐和钾盐伴生矿物的硼同位素组成在 19.91% 至 31.01% 之间变化，与大陆蒸发物（-6.83%–-5.79%）显着不同，但与蒸发浓缩海水中沉淀的盐（10%–36%）非常接近。盐类的 87Sr/86Sr 比值（0.707542 至 0.709461）也接近于古新世海水的值（0.70772 至 0.707830）。岩盐的Br−含量（0.01%~0.25%）和Br×103/Cl比值（0.10~0.52）比常见陆盐高10倍以上。这些特征清楚地表明老挝钾盐矿床是由海水沉积而成的。所有盐沉积序列（石膏-盐石-钾-盐石）中硼和锶同位素的微小变化也表明补给源应该是稳定的，其他大陆水混合的影响可以忽略不计。大型钾盐矿床通常是从海水中沉淀出来的。因此，最近的区域钻探工作和地球化学研究的结果表明，老挝东南部的 Thangon 地层可能存在丰富的钾资源。
Since 2006, we have conducted a geological exploration of the Khammuane area in southeastern Laos. Several thick sequences of potash deposits containing sylvite and carnallite were discovered from drilling Paleocene strata of the Thangon Formation (E1tg). To constrain the origin of the brine that formed thick sequences of salt mineral deposits, we measured the strontium and boron isotope composition of some salt minerals in the potash deposit. Boron isotope composition of halite- and potash-associated minerals in the Khammuane potash deposit varied from 19.91% to 31.01‰, which differs significantly from continental evaporates (−6.83‰–−5.79‰) but is very close to that of salts precipitated from evapo-concentrated seawater (10‰–36‰). The87Sr/86Sr ratios (0.707542 to 0.709461) of salts were also close to the values of Paleocene seawater (0.70772 to 0.707830). The content of Br−(0.01%–0.25%) and Br×103/Cl ratios (0.10–0.52) of halite were >10 times higher than that of common continental salts. These characteristics indicate clearly that the Laos potash deposits were deposited from seawater. The small variation in boron and strontium isotopes in all salt sedimentary sequences (gypsum-halite-potash-halite) also suggests that the recharge source should be stable and the effects of other continental water mixing are negligible. Large-scale potash deposits are commonly precipitated from seawater. Hence, the results of recent regional drilling work and geochemical research suggest extensive potash resources could occur in the Thangon Formation of southeastern Laos.
登录
查看更多内容
影响因子：
5
作者：
Ying-kai Xiao;Dapeng Sun;Yun-Hui Wang;H. Qi;Lin Jin
通讯作者：
Ying-kai Xiao;Dapeng Sun;Yun-Hui Wang;H. Qi;Lin Jin
影响因子：
5
作者：
Weiguo Liu;Yuanyuan Xiao;Zi-cheng Peng;Z. An;Xiaoqing He
通讯作者：
Weiguo Liu;Yuanyuan Xiao;Zi-cheng Peng;Z. An;Xiaoqing He
DOI：
10.1016/0743-9547(93)90021-g
发表时间：
1993
期刊：
Journal of Southeast Asian Earth Sciences
影响因子：
--
作者：
C. Utha-aroon
通讯作者：
C. Utha-aroon
影响因子：
3.9
作者：
Blanca Adriana Méndez-Ortiz-;A. Carrillo-Chavez;E. González-Partida;J. Tritlla;G. Levresse;F. González-Posadas;H. Martinez-Kemp
通讯作者：
Blanca Adriana Méndez-Ortiz-;A. Carrillo-Chavez;E. González-Partida;J. Tritlla;G. Levresse;F. González-Posadas;H. Martinez-Kemp
影响因子：
5
作者：
M. Palmer;J. Edmond
通讯作者：
M. Palmer;J. Edmond