An Investigation of the Effects of Cold, Thick Lithosphere on Deformation of Slowly Slipping Mega-Transforms; The Andrew Bain Transform, SWIR

在这笔资金的支持下，一组美国科学家将加入一艘意大利机遇船，研究西南印度脊的安德鲁·贝恩变换域（ABTD），并将在巡航后的研究中进行合作。ABTD宽，活动转换断层由一系列短接力型伸展盆地组成，连接了一条长而直的南股和一条短而直的北股。意大利R/V Explora号上的新地质和地球物理数据（多波束测深/侧扫描、重力、磁力和多通道地震）与pi之前收集的数据相结合，将提供ABTD的形态构造结构和物理结构的完整视图。这些新数据可用于解决以下问题；1. 主变换位移区位于ABTD内的何处？2. 是什么力量导致了连接ABTD内较长的南、北转换断层的伸展接力盆地的形成？3. 能否建立一个理论/数值模型来解释观测到的ABTD和其他慢滑大变形的形态构造特征？4. Andrew Bain变换的形态和结构如何与大型大陆变换相比较，相似性是否为大陆大变换的变形提供了额外的约束？

Under this funding, a group of US scientists will join an Italian ship of opportunity to study the Andrew Bain Transform Domain (ABTD) of the Southwest Indian Ridge, and will collaborate in the post-cruise research. The ABTD is broad and the active transform fault consists of a series of short relay-type extensional basins connecting a long straight southern strand and a shorter straight northern strand. The new geological and geophysical data (multibeam bathymetry/sidescan, gravity, magnetics and multi-channel seismics) from the expedition on the Italian R/V Explora , when combined with data collected by the PIs previously, will provide a complete view of the morphotectonic fabric and physical structure of the ABTD. These new data can be used to address the following questions; 1. Where does the Principal Transform Displacement Zone lie within the ABTD? 2. What forces led to the formation of the extensional relay basins that connect the longer southern and northern transform faults within the ABTD? 3. Can a theoretical/numerical model be developed to explain the observed morphotectonic signature of the ABTD and other slow-slipping mega-transforms? 4. How does the morphology and structure of the Andrew Bain Transform compare to large continental transforms, and do the similarities provide addition constraints on the deformation of continental mega-transforms?