Numerical thermal modeling of the magmatism at ultraslow spreading zone of hydrothermal area A of Southwest Indian Ridge (SWIR)

doi:10.7523/j.issn.2095-6134.2016.06.011

Abstract

Abstract:

The Chinese DY115-21 cruse acquired valuable OBS seismic data at hydrothermal area A of SWIR and discovered a low-velocity zone which located on the 27th segment of SWIR. Based on velocity section of P wave, we use the finite element method to model the heating process, aiming to discover the possible magmatism and heat effect of the low-velocity zone. The results are given as follows. 1) The current seafloor hydrothermal activity indicates the existence of bottom heating power in the magma chamber. Hotspot causes thermal abnormality in the process of magma moving along the fracture and creates a new magma chamber to provide heat resource for current hydrothermal activities. 2)Temperature-dependent thermal conductivity greatly influenced the results of the thermal modeling. The modeling results show that the moho temperature of the research area is about 910℃ and the heat flux at the hotspot is about 190 mW·m^-2.

Key words: Southwest Indian Ridge, magma chamber, numerical thermal modeling, Moho temperature, hotspot

CLC Number:

P314

BIAN Long, ZHANG Jian, RUAN Aiguo. Numerical thermal modeling of the magmatism at ultraslow spreading zone of hydrothermal area A of Southwest Indian Ridge (SWIR)[J]. , 2016, 33(6): 792-801.

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