Context :

Aims : We investigate the physical conditions of the sources of two metric type II bursts associated with coronal mass ejection ( CME ) expansions with the aim of verifying the relationship between the shocks and the CMEs , by comparing the heights of the radio sources and of the extreme-ultraviolet ( EUV ) waves associated with the CMEs .

Methods : The heights of the EUV waves associated with the events were determined in relation to the wave fronts .
The heights of the shocks were estimated by applying two different density models to the frequencies of the type II emissions and compared with the heights of the EUV waves .
For the event on 13 June 2010 , that included band-splitting , the shock speed was estimated from the frequency drifts of the upper and lower frequency branches of the harmonic lane , taking into account the H/F frequency ratio f _ { H } / f _ { F } = 2 .
Exponential fits on the intensity maxima of the frequency branches were more consistent with the morphology of the spectrum of this event .
For the event on 6 June 2012 , that did not include band-splitting and showed a clear fundamental lane on the spectrum , the shock speed was directly estimated from the frequency drift of the fundamental emission , determined by linear fit on the intensity maxima of the lane .
For each event , the most appropriate density model was adopted to estimate the physical parameters of the radio source .

Results : The event on 13 June 2010 had a shock speed of 590 – 810 km s ^ { -1 } , consistent with the average speed of the EUV wave fronts of 610 km s ^ { -1 } .
The event on 6 June 2012 had a shock speed of 250 – 550 km s ^ { -1 } , also consistent with the average speed of the EUV wave fronts of 420 km s ^ { -1 } .
For both events , the heights of the EUV wave revealed to be compatible with the heights of the radio source , assuming a radial propagation of the type-II-emitting shock segment .

Conclusions :