These are stunning! You have shot a couple of REALLY excellent images here.
The only problem with these is the ISO. Set your camera to a much lower ISO and use a tripod and adjust your other settings accordingly. This will dramatically reduce the noise in the images. In static images (where nothing is moving) you can get away with really low ISO and longer shutter speeds. Take advantage of the fact that nothing is moving and take your time.
Do you have adobe lightroom 3?
That application has incredible noise reduction. So you can probably fix these but obviously it’s much better to shoot the images with lower ISO first.
The tonal range and the overall quality of both of these images are fantastic.
It’s just the noise.
VERY WELL DONE!