|The preparations for this field trip
begin about two weeks before the show. Searles
Valley Minerals technicians begin by
choosing a site
where good crystals are thought to be available and where there is a large enough flat area to allow field trip parking. Then locations for
about 15 holes are marked, each about 100 feet from it's neighbors. A rotary drill bores 16 inch diameter holes into the salt body
at each location. These holes, which are typically 40 feet deep, provides the access needed to recover the hanksite and other crystals.
|The second step occurs four days
field trip when an licensed explosives technician from Alpha Explosives arrive on site to blast the holes.
The blast objective is to loosen crystals within the target depth so they can then later be "blown" onto the surface. After examining the site and talking
with the SVM geologists and technicians, the explosives expert assisted by an SVM crew prepares for setting up the blast.
The explosives technician, assisted by a crew of SVM technicians, measures and marks the primer cord so that the explosives can be accurately
set at the depths where the crystals are to be loosened.
Blocks of exposive are then taped together along the primer cord to provide the explosive force. To avoid damage to the surface, the depth is set so
that all the explosives are below the 20-foot depth.
|Weights are hung on the bottom end of
cord to make sure the explosive assembly goes all the way to the bottom
hole. A weight and primer cord/explosive assembly is then carefully lowered into each hole. Sandbags are also placed on the primer
cord at the top of the hole to keep it in place.
| Home | Site Map | Revised 09/22/2013
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