Mapping tectonic provinces with airborne gravity and radar data in Dronning Maud Land, East Antarctica
Mapping tectonic provinces with airborne gravity and radar data in Dronning Maud Land, East Antarctica
复制标题
利用南极洲东部 Dronning Maud 地的机载重力和雷达数据绘制构造省图
DOI：
10.1111/j.1365-246x.2012.05363.x
复制
发表时间：
2012
影响因子：
2.8
通讯作者：
D. Steinhage
中科院分区：
文献类型：
--
作者：
S. Riedel;W. Jokat;D. Steinhage
南极洲是地质史研究的重要组成部分，
重建超大陆罗迪尼亚和冈瓦那。地层的残留物
可以发现这些古老的陆地块的解体，尽管有很大的不确定性
留在南极洲冰盖下的构造边界位置
普遍缺乏露头和有限的地质数据量。空中和太空
测量是获得全面空间数据覆盖范围的唯一可能
偏远极地地区的地质研究。
超过100000公里的航空地球物理数据，包括无线电回波
在120万平方米的面积上获得了测深、重力和磁力数据
在Dronning Maud Land(DML)中心进行了四次南半球夏季战役
在2001至2005年间。这些数据在这里以同质的
DML地区14°-20°E和70°S地区的地形和重力资料
至78.5°S。关于DML较旧的航空地球物理调查，多达85%的
重力数据覆盖了未勘探的区域。地形图和重力图的分析
通过过滤和均衡分析，异常揭示了有关地质和构造的信息
DML中的结构。不同的重力图提供了大体构造结构的线索
区域。第一次形成了大陆-海洋边界的南部边界
在侏罗纪，冈瓦那的扩散被发现。尤其是中国的山脉
Dronning Maud Land很可能不处于均衡平衡状态。该地区仍是一个令人振奋的
冰川反弹的后果。Jutul-Penck地块作为失败的侏罗系的解释
重力反演可以确定裂谷体系。变薄的陆壳与
周边地质单位强烈支持这一假说。除了在其他方面
解释的异常，数据显示了重力结构，大约开始于
S/东经73.25°/006°，走向西南。我们推测这种模式
代表南部非洲和南部非洲之间的缝合带(EAAO的东端
南极洲的克拉通部分。
Antarctica represents a key component in the investigation of the geological history and
reconstruction of the supercontinents Rodinia and Gondwana. Remnants of the formation
and disintegration of these ancient land masses can be found, although great uncertainties
remain in the location of tectonic boundaries beneath the ice sheet of Antarctica due to
general lack of outcrops and the limited amount of geological data. Airborne and space
measurements are the only possibility to obtain comprehensive spatial data coverage for
geological studies in the remote polar areas.
More than 100000 line kilometers of airborne geophysical data, including radio echo
sounding, gravity and magnetic data, were acquired over an area of 1.2 million square
kilometers in the center of Dronning Maud Land (DML) over four austral summer campaigns
between 2001 and 2005. The data are presented here as compilations of homogeneous
topographic and gravity data for the DML region, ranging from 14°W to 20°E and from 70°S
to 78.5°S. With respect to older airborne geophysical investigations in DML, up to 85% of the
gravity data cover unexplored regions. Analyses of the maps of topography and gravity
anomalies, by filtering and isostatic analysis, reveal information about geologic and tectonic
structures in DML. Different gravity maps provide hints for the general tectonic fabric of the
area. For the first time the southern boundary of the continent-ocean boundary formed
during the Jurassic dispersal of Gondwana is identified. Especially the mountain range in
Dronning Maud Land is most likely not in isostatic balance. The area is still uplifting as a
consequence of glacial rebound. Interpretations of the Jutul-Penck graben as failed Jurassic
rift system can be confirmed by the gravity inversion. Thinned continental crust compared to
the surrounding geological units strongly support this hypothesis. Besides on other
interpreted anomalies, the data shows a gravity structure, which starts approximately at
73.25°S/006°E and strikes in southwestern direction. We speculate that this pattern
represents the suture zone (eastern termination of EAAO) between southern Africa and the
cratonic part of Antarctica.