Propagation of Magma-Filled Cracks

Deep open storage and shallow closed transport system for a continental flood basalt sequence revealed with Magma Chamber Simulator

“…To further estimate the plausibility of the two-stage model presented in the previous section, it is possible to approximate the thermophysics of assimilation based on a model of melt transport through cracks. The transport of magma via a crack network has been analyzed by many authors (e.g., Weertman 1971;Spera 1980;Shaw 1980;Emerman et al 1986;Bruce and Huppert 1990;Spera 1992;Takada 1994;Rubin 1995). Flood basalts have generally been extruded during relatively brief episodes throughout geologic history and are a first-order petrotectonic association.…”

“…The essence of the problem for application to low-ε Nd CT1 magmatism is to demark in parameter space the conditions where the wallrock-magma contact migrates either into wallrock (i.e., wallrock meltback, whereby magma is contaminated) or into the magma (frozen magma near wallrock-magma contact chemically insulates ascending magma from contamination). Here, we examine flow in a dike from a thermal perspective once a fracture filled with magma has been generated, perhaps by the magma fracture mechanism discussed elsewhere (Shaw 1980;Spera 1992;Rubin 1995;Detournay 2016). The key aspect for contamination of mantle-derived magmas by Archean crust is the crustal depth where assimilation occurs.…”

Insights Into Fault‐Magma Interactions in an Early‐Stage Continental Rift From Source Mechanisms and Correlated Volcano‐Tectonic Earthquakes

“…Although the magma intrusion itself is aseismic, the rocks adjacent to intrusions experience failure, potentially due to gases exsolving and causing fluid-driven fracturing in the solid rock (e.g., Rubin, 1995). Although the magma intrusion itself is aseismic, the rocks adjacent to intrusions experience failure, potentially due to gases exsolving and causing fluid-driven fracturing in the solid rock (e.g., Rubin, 1995).…”

“…Although the magma intrusion itself is aseismic, the rocks adjacent to intrusions experience failure, potentially due to gases exsolving and causing fluid-driven fracturing in the solid rock (e.g., Rubin, 1995). However, it remains unclear whether dike-related seismicity results from stressed, intact rock failing above and below the dikes without effects from fluid percolation (e.g., Rowland et al, 2007) or whether the earthquake rupture initiates in rock with magma-filled cracks (e.g., Belachew et al, 2013;Rubin, 1995). However, it remains unclear whether dike-related seismicity results from stressed, intact rock failing above and below the dikes without effects from fluid percolation (e.g., Rowland et al, 2007) or whether the earthquake rupture initiates in rock with magma-filled cracks (e.g., Belachew et al, 2013;Rubin, 1995).…”

“…Fault rupture and related seismicity may also result from stress concentrations around the edges of blade-shaped propagating dikes (e.g., Belachew et al, 2011;Bonafede & Danesi, 1997). However, it remains unclear whether dike-related seismicity results from stressed, intact rock failing above and below the dikes without effects from fluid percolation (e.g., Rowland et al, 2007) or whether the earthquake rupture initiates in rock with magma-filled cracks (e.g., Belachew et al, 2013;Rubin, 1995). The latter's source mechanism would have a dilatational component due to the magma and gas inflation along the fault zone (Belachew et al, 2013;Minson et al, 2007), whereas the former would result in a double-couple (DC) mechanism (e.g., Ágústsdóttir et al, 2016).…”