LOGGING THIS CACHE: Send the following answers
(A)-(F) to me when you log the cache. Some can be answered at the
listed co-ordinates. Some will require you to obtain some
information at the site, and perform additional research. No
measurements or photos will be accepted. Do not post your answers
in logs, or photos of the sign.
On the board at the listed co-ordinates
(A) What is the name of this feature?
(B) "This horizontal sheet formed... some (B) million years ago..".
How many years?
Further research - these answers are not available
at the site
(C) The information sign describes a process in the second
paragraph. Name the process, it has two words and 19 letters.
(D) What is the more accurate classification of this feature -
volcanic or plutonic?
Time to earn your money :) - you are looking
online for a document around midway through the last century. In
this document, I would like the following details.
(E) What is the name of the igneous rock that has intruded into the
sandstone at this location?
(F) According to this article, seventy percent of typical specimens
of this rock (E) are made up from three minerals. What are the
three minerals, and what percentage do they each represent?
(optional) Where did the strange cache name come from?
DESCRIPTION: This earthcache is intentionally
lighter on details - this time you have to do the
digging - well, not literally! Consider this an earthpuzzlecache!
At the listed co-ordinates you will find a good example of a sill -
a remnant of volcanic activity from many millions of years ago. A
sill is formed when magma flows between layers of existing rocks
and cools. Wikipedia
adds...
Sills are always parallel to beds (layers) of the
surrounding country rock. Usually they are in a horizontal
orientation, although tectonic processes can cause rotation of
sills into near vertical orientations. They can be confused with
solidified lava flows; however there are several differences
between them. Intruded sills will show partial melting and
incorporation of the surrounding country rock. On both the "upper"
and "lower" contact surfaces of the country rock into which the
sill has intruded, evidence of heating will be
observed.