Effects of axially variable diking rates on faulting at slow spreading mid-ocean ridges
Effects of axially variable diking rates on faulting at slow spreading mid-ocean ridges
复制标题
轴向可变筑堤速率对缓慢扩张的洋中脊断层作用的影响
DOI：
10.1016/j.epsl.2016.10.033
复制
发表时间：
2017
影响因子：
5.3
通讯作者：
Choi, Eunseo
中科院分区：
文献类型：
--
作者：
Tian, Xiaochuan;Choi, Eunseo
岩脉注入的岩浆供应在缓慢扩张的洋中脊的一段内可能变化很大，但这种变化对构造的影响尚未完全了解。在这里，我们使用三维数值模型来量化的影响，可变筑堤率的断层模式在一个20公里长的缓慢扩展的山脊段。除了端元断裂模式，其中长期的拆离断层或短期的正断层形成沿着整个段，我们新确定的过渡模式，其中拆离和短期的正断层同时形成，但在各自的域由转移断层分开。不同的断层模式可以更好地与平均岩脉侵入率，而不是最高或最低的速度沿着段。沿轴向应力耦合倾向于均匀化断层偏移沿着段，抑制与极端局部筑堤率相关的特定断层模式的主导。这种负效应解释了为什么有时甚至在以前认为不利的地区也能形成拆离断层。我们的研究结果进一步表明，一个长的（>15公里）和连续的拆离，部分覆盖年轻的断层，可以创建一个海洋核复杂的断层减弱快，筑堤率低。然而，当断层减弱缓慢且筑堤速率适中时，断层以过渡模式发生，仅在部分区段长度上产生拆离。
Magma supply for dike injection can be highly variable within a segment of a slow-spreading mid-ocean ridge but the tectonic impact of this variability is not fully understood. Here, we use three-dimensional numerical models to quantify the effects of variable diking rates on the faulting mode at a 20 km-long slow spreading ridge segment. In addition to end-member faulting modes in which long-lived detachment faults or short-lived normal faults form along the whole segment, we newly identify a transitional mode in which a detachment and a short-lived normal fault form simultaneously but in respective domains separated by a transfer fault. Different faulting modes can be better correlated with the average dike intrusion rate, rather than the highest or lowest rate along the segment. Along-axis stress coupling tends to homogenize fault offset along the segment, inhibiting the domination of a particular faulting mode associated with an extreme local diking rate. This homogenizing effect explains why detachment faults can sometimes form even in the regions previously considered as unfavorable. Our results further suggest that a long (>15 km) and continuous detachment, partially overlain by younger faults, can create an oceanic core complex when faults weaken fast and diking rate is low. When faults weaken slow and diking rate is moderate, however, faulting occurs in the transitional mode, producing a detachment over only a part of the segment length.
影响因子：
5.3
作者：
MacLeod, C. J.;Searle, R. C.;Harris, M.
通讯作者：
Harris, M.
影响因子：
3.7
作者：
M. Manga;M. Hornbach;A. Le Friant;O. Ishizuka;N. Stroncik;T. Adachi;M. Aljahdali;G. Boudon;C. Breitkreuz;A. Fraass;A. Fujinawa;R. Hatfield;M. Jutzeler;K. Kataoka;S. Lafuerza;F. Maeno;M. Martínez-Colón;M. McCanta;S. Morgan;M. Palmer;T. Saito;A. Slagle;A. Stinton;K. Subramanyam;Y. Tamura;P. Talling;B. Villemant;D. Wall-Palmer;Fei Wang
通讯作者：
M. Manga;M. Hornbach;A. Le Friant;O. Ishizuka;N. Stroncik;T. Adachi;M. Aljahdali;G. Boudon;C. Breitkreuz;A. Fraass;A. Fujinawa;R. Hatfield;M. Jutzeler;K. Kataoka;S. Lafuerza;F. Maeno;M. Martínez-Colón;M. McCanta;S. Morgan;M. Palmer;T. Saito;A. Slagle;A. Stinton;K. Subramanyam;Y. Tamura;P. Talling;B. Villemant;D. Wall-Palmer;Fei Wang
大西洋中脊北纬 30° 亚特兰蒂斯地块滑脱断层的地震活动
DOI：
--
发表时间：
2012
期刊：
影响因子：
--
作者：
J. Collins;Deborah K. Smith;J. McGuire
通讯作者：
J. McGuire