Rock of Ages

Winter 2015 - Volume 19 Number 1

 RockOfAges

Rock of Ages
by Sally J Cullen, MD, MS

This photograph was taken in Zion National Park in Utah. The monument pictured was formed
by millennia of cascading water cutting through and eroding the sedimented and lithified Navajo
Sandstone. The incredible rock layers of Zion are part of a system stretching from Bryce Canyon to the
Grand Canyon.

Dr Cullen retired in 2012 after more than 32 years practicing medicine. She now uses
photography to show how our national parks are our great heritage, and how
they can be our great legacy if we protect and celebrate them. More of Dr Cullen's
photography may be seen at: www.myparkphotos.com/ property/SallyCullen.html.

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