High speed CMEs are expected to drive shocks in the lower corona as they do in the interplanetary space. The direct detection of these shocks in coronagraph images, however, has been very uncertain with a couple known examples. In this paper, I argue that this situation can change thanks to the high sensitivity of the LASCO instrument which permits the detection of even weak shocks. Also recent MHD simulations can lead to better understanding of the various features seen on the coronagraph images. Finally, I will present two types of possible shock signatures with several examples for each type.
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