The Mason Esker is the longest esker in the northern hemisphere.
It begins in DeWitt, Michigan, and runs south and a bit east. It
extends to a point south of the town of Mason, Michigan. The esker
runs in both Clinton and Ingham counties. The Mason Esker is listed
as being 22 miles long although extensions of this esker run a full
35 miles. At times it will be from 200 feet to a half mile wide.
Unfortunately much of the esker is no longer able to be seen. There
are a few areas where it is persevered and we are taking you to one
An Esker is a long, winding ridge of stratified sand and gravel
which occur from glacier melt. It is formed in ice-walled tunnels
by streams which flowed within and under glaciers. After the
retaining ice walls melt away, stream deposits remain as long
winding ridges. Eskers may also form above glaciers by accumulation
of sediment in glacial channels, in crevasses, in linear zones
between stagnant blocks, or in narrow embayment at glacier margins.
Eskers form near the terminal zone of glaciers, where the ice is
not moving as fast and is relatively thin.
Eskers will very in size and shape as you will see at the locations
we are taking you. The shape and size is determined by flow and
melting of the basal ice. They may exist as a single channel, or
may be part of a branching system with tributary eskers. They are
not often found as continuous ridges, but have gaps that separate
the winding segments. The ridge crests of eskers are not usually
level for very long, and are generally knobby. Eskers may be
broad-crested or sharp-crested with steep sides. The heights of any
esker will vary as well. The Mason Esker is dated from somewhere
between 10,000 and 12,000 years ago.
What has happened to this major esker? It has been used to build
roads, bridges and building through out Michigan. The sand and
gravel here have been mined since the settlers first came to this
part of Michigan. Because of the extensive mining of the esker it
has all but disappeared. There are still some mines left on the
esker but they are small today.
Along with your visit here you can also visit Bancroft Park in
north-east Lansing. Here you will find some of the esker that is
left and protected. The area we are taking you is the tail of the
esker and is farmland where the esker is persevered because of
farming not industrial use.
To log the find on this Earthcache you will have to go to the
following locations and answer the questions for each stop. Please
do not post your answers on the cache page, just your photo.
1. At the posted co-ords and also at N42 30.558 W084 21.690 you
will take an altimeter reading then tell me the height of the esker
at this point.
2. Go to N42 30.967 W084 21.861. This is a beautiful view of this
esker. At this point take a photo of yourself with any of the
landscape of the area behind you.
3. Go and visit N42 31.438 W084 22.267 at this point you will find
2 things one of which is a sign. Tell me what the name of this
place is. Next tell me what is happening to the esker at this