东南极边缘的广泛的河流表面调节了冰盖的演变
Guy J G Paxman1, Stewart S R Jamieson1, Neil Ross2
1Department of Geography, Durham University, Durham, UK.
概括
研究人员在东南极洲发现了古老的沿海平原,这些平原在冰盖下面保存着. 这些冰河前的地形揭示了构造历史和河流侵蚀如何塑造南极景观,影响了冰盖的行为和气候变化反应.
科学领域:
- 地质学和冰川学
- 古地质学 古地质学
- 气候科学 气候科学
背景情况:
- 南极床的地形对于了解冰盖动态和冰川历史至关重要.
- 关于冰河前景观演变及其对冰盖行为影响的知识有限.
研究的目的:
- 研究冰河前的景观及其对南极冰盖演变的影响.
- 揭示了在冰河化之前塑造南极地形的过程.
主要方法:
- 无线电回声声被用来绘制冰下地形的地图.
- 应用静态调整来确定冰河前的地形高度.
主要成果:
- 在东南极冰边缘下面发现了广的平面,被确定为由河流侵蚀形成的沿海平原的残余.
- 这些表面可以追溯到东南极洲与澳大利亚分离 (10080万年前) 和冰川开始 (34万年前) 之间的时间.
- 这些表面的保存表明选择性侵蚀有限,冰流通过遗传结构和山谷道,形成过深的低谷.
结论:
- 由河流侵蚀形成的冰河前景观,显著调节了东南极冰盖对气候变化的反应.
- 遗传的地形,而不是均的侵蚀,指导冰流和影响冰川动态.
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