Surface uplift and convective rainfall along the southern Central Andes (Angastaco Basin, NW Argentina)
Surface uplift and convective rainfall along the southern Central Andes (Angastaco Basin, NW Argentina)
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中安第斯山脉南部（阿根廷西北部安加斯塔科盆地）沿线的地表隆起和对流降雨
DOI：
10.1016/j.epsl.2016.02.009
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发表时间：
2016
影响因子：
5.3
通讯作者：
Strecker
中科院分区：
文献类型：
--
作者：
Pingel;Alonso;Cottle;Poletti;Rohrmann;Schmitt;Stockli;Strecker
阿根廷西北部造山普纳高原和东部邻近山间盆地的稳定同位素和沉积记录提供了安第斯山脉中南部山脉隆升和随之而来的古环境变化的独特晚新生代记录。今天，该地区的集中降水发生在东科迪勒拉山脉和潘皮纳斯山脉的东侧迎风侧翼，而造山带内部则构成高海拔地区，向西方向干旱条件日益增强。与许多山区一样，这种水文和地形梯度通常通过大气水的氧和氢稳定同位素比率与海拔之间的系统关系来反映。插入沉积序列中的可同位素测定的火山灰的玻璃部分构成了保留古代降水氢同位素组成信号的环境代理。因此，这种同位素组成有助于阐明与地形生长相关的气候和构造过程，最终控制山区降水的空间模式。然而，在南纬 25.5 至 27° 之间，目前基于河流的氢同位素流失率非常低，可能是由于主导径流的深对流季节性风暴所致。如果不考虑这种情况对过去可用水分的影响，可能会导致对降雨代理记录的误解。在这里，我们提供了从东部科迪勒拉山脉和潘皮纳斯山脉不同沉积盆地的 34 个火山灰层中提取的火山玻璃 (δDg) 的氢同位素数据。结合之前发表的 δDg 记录以及我们对 17 个凝灰岩样品进行的精制 U-Pb 和 (U-Th)/He 锆石地质年代学，我们证明了与 Angastaco 盆地古环境变化相关的氢同位素变化，该盆地在 Mio-上新世晚期从邻近的前陆演化为断层限制的山间盆地。我们揭示了Mio-上新世地形生长的环境影响以及相关的地形对安第斯山脉中南部降雨长期氢同位素记录的影响，并可能确定区域同位素递减率的时间变化，这也可能适用于具有类似地形边界条件的其他地区。
Stable-isotopic and sedimentary records from the orogenic Puna Plateau of NW Argentina and adjacent intermontane basins to the east furnish a unique late Cenozoic record of range uplift and ensuing paleoenvironmental change in the south-central Andes. Today, focused precipitation in this region occurs along the eastern, windward flanks of the Eastern Cordillera and Sierras Pampeanas ranges, while the orogen interior constitutes high-elevation regions with increasingly arid conditions in a westward direction. As in many mountain belts, such hydrologic and topographic gradients are commonly mirrored by a systematic relationship between the oxygen and hydrogen stable isotope ratios of meteoric water and elevation. The glass fraction of isotopically datable volcanic ash intercalated in sedimentary sequences constitutes an environmental proxy that retains a signal of the hydrogen-isotopic composition of ancient precipitation. This isotopic composition thus helps to elucidate the combined climatic and tectonic processes associated with topographic growth, which ultimately controls the spatial patterns of precipitation in mountain belts. However, between 25.5 and 27°S present-day river-based hydrogen-isotope lapse rates are very low, possibly due to deep-convective seasonal storms that dominate runoff. If not accounted for, the effects of such conditions on moisture availability in the past may lead to misinterpretations of proxy-records of rainfall. Here, we present hydrogen-isotope data of volcanic glass (δDg), extracted from 34 volcanic ash layers in different sedimentary basins of the Eastern Cordillera and the Sierras Pampeanas. Combined with previously publishedδDg records and our refined U–Pb and (U–Th)/He zircon geochronology on 17 tuff samples, we demonstrate hydrogen-isotope variations associated with paleoenvironmental change in the Angastaco Basin, which evolved from a contiguous foreland to a fault-bounded intermontane basin during the late Mio–Pliocene. We unravel the environmental impact of Mio–Pliocene topographic growth and associated orographic effects on long-term hydrogen-isotope records of rainfall in the south-central Andes, and potentially identify temporal variations in regional isotopic lapse rates that may also apply to other regions with similar topographic boundary conditions.
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位于阿根廷西北部萨尔塔省 Calchaquí 山谷北端的 Quebrada de los Colorados 地层保留了始新世中期以来同沉积变形的证据
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
Myung;Sang
通讯作者：
Sang
影响因子：
5.3
作者：
Rohrmann;Strecker;Bookhagen;Sachse;Pingel;Alonso;Schildgen;Montero
通讯作者：
Montero
影响因子：
5.8
作者：
H. Pingel;R. Alonso;A. Mulch;A. Rohrmann;M. Sudo;M. Strecker
通讯作者：
H. Pingel;R. Alonso;A. Mulch;A. Rohrmann;M. Sudo;M. Strecker
阿根廷西北部东科迪勒拉山脉晚始新世-上新世盆地演化（25°–26°S）：对安第斯造山楔发育的区域影响
影响因子：
3.2
作者：
B. Carrapa;S. Bywater‐Reyes;P. DeCelles;E. Mortimer;G. Gehrels
通讯作者：
G. Gehrels
影响因子：
5.8
作者：
Canavan, Robin R.;Carrapa, Barbara;Schoenbohm, Lindsay M.
通讯作者：
Schoenbohm, Lindsay M.