Hi Chris,
No steam but I did live in Europe
for some years and can verify trains here are quite a bit =
different. What
I see here is usually 3 or 4 large diesel locomotives about 200 tones =
each pulling
nearly 100 cars filled with corn or wheat to about 120 tones per =
car. I
haven’t investigated where in the path the seismic noise =
originates but
there are a couple of bridges. My bet would be on the transition =
across a
bridge to earth since we do not have bedrock support in this area. =
The
car length and the bridge lengths are also similar so there could be a =
beating
frequency over the abutments. We also use shorter sections of rail =
in
place of the long welded rails you have so there are rail joints adding =
to
surface pounding. The trains here are required to whistle at every =
road
crossing and the track turns nearly directly away from me so I can count =
miles
of distance just by listening to the train whistle. I can see the =
signal
from the train which is about 1 mile in length until the far end is 3 =
– 4
miles from my house. It might be interesting to do more research =
on this
with frozen ground, wet ground and dry ground conditions. =
Randy