Holocene glaciations in the Ema Glacier valley, Monte Sarmiento Massif, Tierra del Fuego
Holocene glaciations in the Ema Glacier valley, Monte Sarmiento Massif, Tierra del Fuego
复制标题
埃玛冰川谷、萨米恩托山、火地岛的全新世冰川
DOI：
10.1016/j.palaeo.2007.12.002
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
P. Holmlund
中科院分区：
文献类型：
--
作者：
J. Strelin;G. Casassa;G. Rosqvist;P. Holmlund
在Monte Sarmiento Massif东侧的火地岛Ema冰川谷进行的调查，使五个全新世冰川事件的认识成为可能。最古老的冰川推进沉积了所谓的埃玛冰川外部冰碛，可能发生在6000和5000 14 C y BP之间，而不排除这些沉积物来自晚冰期的可能性。其余四个再沉积形成了一个复杂的内冰碛系统，非正式地称为埃玛冰川内冰碛。最古老的公认的直到单位，构成近端冰碛系统沉积前不久3135 - 14 C Y BP，当冰川湖沉积发生在冰川衰退。随后的冰川进展积累到约1288 14 C Y，695 14 C Y后不久，379 14 C Y和60 Y BP之间。这一全新世冰川事件年表与其他作者为达尔文科迪勒拉（Cordillera）的菲奥多·皮亚（Fiordo Pía）建立的年表相吻合，并得到了很好的补充。Ema-Pía年代学被用来初步校准一系列冰碛带，这些冰碛带以前在乌斯怀亚附近的山脉中被确定，位于被测区域东南150公里处。一个比较图表表明，火地岛新冰川再进的年代学数据与更北的巴塔哥尼亚南部安第斯山脉的年代学数据一致。由此可见，火地岛安第斯地区和巴塔哥尼亚南部冰川的全新世行为本质上是对同一区域气候变化的反应。
Investigations carried out in the Ema Glacier valley, Tierra del Fuego, on the eastern side of Monte Sarmiento Massif, enable the recognition of five Holocene glacial events. The oldest glacial advance deposited the so-called external moraines of Ema Glacier, with a probable occurrence between 6000 and 5000 14 C y BP without discarding the potential for these deposits to be from Lateglacial time. The remaining four readvances built up a complex inner moraine system named informally internal moraines of Ema Glacier. The oldest recognized till unit that constitutes this proximal moraine system was deposited shortly before 3135 14 C y BP, when glaciolacustrine sedimentation took place during glacier recession. Subsequent glacial advances accumulated till at about 1288 14 C y, shortly after 695 14 C y, and between 379 14 C y and 60 y BP. This chronology of Holocene glacier events coincides with and is well complemented by the one established by other authors for Fiordo Pía at Cordillera Darwin, 75 km to the east. The Ema-Pía chronology is used to calibrate tentatively a series of moraine belts previously identified in the mountain ranges adjacent to Ushuaia, 150 km SE of the surveyed region. A comparative chart shows that the chronological data obtained for the neoglacial readvances in Tierra del Fuego are in accordance with those for the southern Patagonian Andes further north. It follows that the Holocene behavior of the glaciers in the Andean region of Tierra del Fuego and southern Patagonia is essentially a response to the same regional climate change.