Neogene to Quaternary stratigraphic evolution of the Antarctic Peninsula, Pacific Margin offshore of Adelaide Island: Transitions from a non-glacial, through glacially-influenced to a fully glacial state
Neogene to Quaternary stratigraphic evolution of the Antarctic Peninsula, Pacific Margin offshore of Adelaide Island: Transitions from a non-glacial, through glacially-influenced to a fully glacial state
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阿德莱德岛近海太平洋边缘南极半岛新近纪至第四纪地层演化：从非冰川状态、受冰川影响状态到完全冰川状态的转变
DOI：
10.1016/j.gloplacha.2017.07.002
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发表时间：
2017
影响因子：
3.9
通讯作者：
Hernández-Molina F
中科院分区：
文献类型：
--
作者：
Hernández-Molina F
基于反射多道地震剖面和带状测深研究，对南极半岛太平洋边缘（PMAP）阿德莱德岛近海大陆边缘进行了详细的地貌和地震地层学分析。我们对跨陆架至大陆隆起的边缘进行了综合研究，建立了新的年代学约束，并对影响PMAP的构造演化和环境变化提供了新的解释。地层堆积模式记录了边缘沉积样式的主要转变，勾勒出其演化的三个阶段。第一个非冰期（早白垩世至中新世中期）包含了一个从主动边缘到被动边缘（早中新世）的过渡。第二个冰川影响期（中新世中晚）以明显的沉积堆积和沉降为标志。在第二个间隔期结束时，冰原在边缘的中间冰架上移动，而外部冰架则经历了罕见的递进事件。第三个是完全冰川期，它清楚地显示了冰川主导的边缘条件。这段时间分为三个小阶段。在第一阶段（中新世晚期至上新世初期），频繁的地面冰向陆架断裂推进，沉积了一个初始的前积单元。一个主要的截断面标志着这一阶段的结束，这与斜坡底部广泛的块体搬运沉积相吻合。在第二次冰缘递进阶段（上新世早期至中更新世），叠置模式清晰地记录了递进冰期序列。中更新世至今的第三次冰川边缘沉积阶段的开始，对应着中更新世过渡时期全球气候的一次重要转变。今天在边缘观察到的形态沉积特征在中新世晚期开始发展，但直到上新世末期和中更新世之间的某个时期才完全建立起来。在这两个时间间隔之间，玛格丽特槽的东北向横向迁移也在边缘演化中发挥了关键作用，因为它控制了跨陆架的冰盖排水路径，从而影响了斜坡和隆起形态的发展。由于海槽的迁移导致了沉积过程的变化，阿德莱德岛近海地区与PMAP的其他地区不同。这项研究证实了PMAP是解码、重建和联系过去构造和气候变化的特殊地点。研究区不仅明确记录了最相关的沉积样式变化，而且还记录了持续的顺、下坡沉积过程的相对重要性。我们的研究方法可以扩展到其他领域，并与其他技术相结合，以了解整个南极大陆边缘和冰盖的演变和全球联系。
A detailed morphologic and seismic stratigraphic analysis of the continental margin offshore of Adelaide Island on the Pacific Margin of the Antarctic Peninsula (PMAP) is described based on the study of a regular network of reflection multichannel seismic profiles and swath bathymetry. We present an integrated study of the margin spanning the shelf to the continental rise, establish novel chronologic constraints and offer new interpretations on tectonic evolution and environmental changes affecting the PMAP. The stratigraphic stacking patterns record major shifts in the depositional style of the margin that outline three intervals in its evolution. The first non-glacial interval (Early Cretaceous to middle Miocene) encompasses a transition from an active to a passive margin (early Miocene). The second glacially-influenced interval (middle to late Miocene) is marked by pronounced aggradational sedimentary stacking and subsidence. Ice sheets advanced over the middle shelf of the margin at the end of this second interval, while the outer shelf experienced rare progradational events. The third, fully glaciated interval shows clear evidence of glacially dominated conditions on the margin. This interval divides into three minor stages. During the first stage (late Miocene to the beginning of the Pliocene), frequent grounded ice advances to the shelf break began, depositing an initial progradational unit. A major truncation surface marked the end of this stage, which coincided with extensive mass transport deposits at the base of the slope. During the second progradational glacial margin stage (early Pliocene to middle Pleistocene), stacking patterns record clearly prograding glacial sequences. The beginning of the third aggradational glacial margin stage (middle Pleistocene to present) corresponded to an important shift in global climate during the Mid-Pleistocene Transition. Morphosedimentary characteristics observed along the margin today began to develop during the latest Miocene but did not become fully established until sometime during the interval between the end of the Pliocene and middle Pleistocene. Between these two time intervals, the northeastward lateral migration of the Marguerite Trough also played a critical role in margin evolution, as it controlled ice sheet drainage pathways across the shelf, which in turn influenced development of slope and rise morphologies. Areas offshore from Adelaide Island differ from other areas of the PMAP due to changes in sedimentary processes that resulted from migration of the trough. This study confirms that the PMAP represents an exceptional locality for decoding, reconstructing and linking past tectonic and climatic changes. The study area specifically records not only the most relevant changes in depositional style, but also the relative importance of persistent along- and down-slope sedimentary processes. Our study approach can be extended to other areas and integrated with additional techniques to understand the evolution and the global linkages of the entire Antarctic continental margin and the ice sheets.
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南极半岛太平洋边缘的深拖曳调查：外大陆架和上斜坡晚第四纪沉积物的形态和声学特征研究
DOI：
10.1029/ar068p0097
发表时间：
2013
期刊：
Geological Society, London, Special Publications
影响因子：
--
作者：
L. Vanneste;R. Larter
通讯作者：
R. Larter
板块重组：北大西洋周围新近纪晚期快速沉降和沉积的原因？
影响因子：
2.7
作者：
S. Cloetingh;F. Gradstein;F. Gradstein;Henk Kooi;A. C. Grant;Michael A. Kaminski
通讯作者：
Michael A. Kaminski
影响因子：
64.8
作者：
N. White;B. Lovell
通讯作者：
B. Lovell
DOI：
--
发表时间：
2000
期刊：
影响因子：
--
作者：
M. Canals;R. Urgeles;A. Calafat
通讯作者：
A. Calafat
深海钻探项目的初步报告，35
DOI：
--
发表时间：
1976
期刊：
影响因子：
--
作者：
C. Hollister;C. Craddock
通讯作者：
C. Craddock