Continental Cratons

Cratons are the cores of continents and have remained stable for the last 2.5 billion years. Many seismic models of the cratonic lithosphere contain very high velocity that increases with depth and lack a low-velocity zone. These features are difficult to reconcile with the temperature structures inferred from surface heat-flow data and mantle-xenolith thermobarometry. We showed, using forward modeling of Rayleigh wave phase velocity, that it is difficult to find a temperature structure that can simultaneously match the xenolith and phase-velocity observations (Hirch et al., G3, 2015). If xenoliths can be considered representative of present-day mantle thermal conditions, the composition of cratonic lithosphere cannot consist only of peridotite.

 

 

Continental Cratons

Cratons are the cores of continents and have remained stable for the last 2.5 billion years. Many seismic models of the cratonic lithosphere contain very high velocity that increases with depth and lack a low-velocity zone. These features are difficult to reconcile with the temperature structures inferred from surface heat-flow data and mantle-xenolith thermobarometry. We showed, using forward modeling of Rayleigh wave phase velocity, that it is difficult to find a temperature structure that can simultaneously match the xenolith and phase-velocity observations (Hirch et al., G3, 2015). If xenoliths can be considered representative of present-day mantle thermal conditions, the composition of cratonic lithosphere cannot consist only of peridotite.

 

 

Continental Cratons

Cratons are the cores of continents and have remained stable for the last 2.5 billion years. Many seismic models of the cratonic lithosphere contain very high velocity that increases with depth and lack a low-velocity zone. These features are difficult to reconcile with the temperature structures inferred from surface heat-flow data and mantle-xenolith thermobarometry. We showed, using forward modeling of Rayleigh wave phase velocity, that it is difficult to find a temperature structure that can simultaneously match the xenolith and phase-velocity observations (Hirch et al., G3, 2015). If xenoliths can be considered representative of present-day mantle thermal conditions, the composition of cratonic lithosphere cannot consist only of peridotite.

 

 

Continental Cratons

Cratons are the cores of continents and have remained stable for the last 2.5 billion years. Many seismic models of the cratonic lithosphere contain very high velocity that increases with depth and lack a low-velocity zone. These features are difficult to reconcile with the temperature structures inferred from surface heat-flow data and mantle-xenolith thermobarometry. We showed, using forward modeling of Rayleigh wave phase velocity, that it is difficult to find a temperature structure that can simultaneously match the xenolith and phase-velocity observations (Hirch et al., G3, 2015). If xenoliths can be considered representative of present-day mantle thermal conditions, the composition of cratonic lithosphere cannot consist only of peridotite.