| Note Mt. St.Helens, The
quakes are not deep so it does not have access to the magma chamber for
a substantial eruption at this time, will this simmering increase in
depth though? Field Project: Examine a local stream
of choice, both during a dry period and during or after a rain. pick a
stream that is it not too large, that you can actually wade in.
Observe and comment on:
1) The substrate-rock covering, are they clean is moss or algae or
sediment covering the rocks
2) Are there soapy bubble present and if so probable source.
3) Is there an oily sheen or iron staining.
4) The relative clarity of the water, is the bottom clear as a
bell in two feet of water, look at some deeper locations? What is
in the water that is making it cloudy?
5) What is the flow observe the depth-width and velocity of the
stream. Use some floating material or food dye to determine velocity.
Time the movement of the tracer over a measured distance of say 25 feet.
6) Determine flow by multiplying width x depth x velocity.
Velocity = distance traveled/time in seconds. Where does the stream
begin and what river does it feed into?
7)What are the main threats to the watershed area of your stream,
comment on land uses that either protect or threaten it.
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