Rock Art Stability Index Field Study Niccole Villa Cerveny Mesa Community College Niccole Villa Cerveny Mesa Community College

What is Rock Art  Petroglyphs - images pecked or scratched into rock surfaces  Pictographs - images painted on rock surfaces  Rock Alignments/Geoglyphs - rocks placed in alignment to form images  Intaglios - removal of desert pavement to create images on the ground  Petroglyphs - images pecked or scratched into rock surfaces  Pictographs - images painted on rock surfaces  Rock Alignments/Geoglyphs - rocks placed in alignment to form images  Intaglios - removal of desert pavement to create images on the ground

Petroglyphs N. Cerveny © 2005

Pictographs J McFaul © 2002

Geoglyphs/rock alignments N. Cerveny © 2005

Intaglios N. Cerveny © 2005

So why do we need a rock art panel stability index?

Weathering/Erosion Refresher  Geomorphology - study of the changing shape of the earth  Weathering - the breakdown of rock “in situ” (in place)  Erosion - the transport of weathered material  Weathering is the beginning to changing the shape of the earth  Geomorphology - study of the changing shape of the earth  Weathering - the breakdown of rock “in situ” (in place)  Erosion - the transport of weathered material  Weathering is the beginning to changing the shape of the earth

Rock Art Stability Index  Setting the stage of the landscape  Stone preparing for detatchment  Incremental loss of stone material  Loss of chunks (break-off of stone)  Rock Coatings  Setting the stage of the landscape  Stone preparing for detatchment  Incremental loss of stone material  Loss of chunks (break-off of stone)  Rock Coatings

Character Value  Examine a panel for each weathering form, then score 0 to 3  O = not present  1 = Barely noticeable  2 = Obvious  3 = Very Serious Concern  ***There are no 1/2-sies  Examine a panel for each weathering form, then score 0 to 3  O = not present  1 = Barely noticeable  2 = Obvious  3 = Very Serious Concern  ***There are no 1/2-sies

Setting the Stage: Fissures & Rock Weaknesses  Fissures independent of stone lithification  Fissures dependent on stone lithification  Changes in textural anomalies  Rock weaknesses (Moh’s)  Fissures independent of stone lithification  Fissures dependent on stone lithification  Changes in textural anomalies  Rock weaknesses (Moh’s)

Preparing for Detatchment  Fissuresol future location  Roots  Plant growth near or on panel  Scaling  Splintering  Undercutting  Weathering-rind development  Other forms indicating future detachment  Fissuresol future location  Roots  Plant growth near or on panel  Scaling  Splintering  Undercutting  Weathering-rind development  Other forms indicating future detachment

Loss of stone material incrementally  Abrasion from sediment  Anthropogenic cutting  Aveolization  Crumbly Disintigration  Flaking  Granular disintigration  Loss parallel to stone structure  Lithobiont Pitting  Lith release of Wx- rind “dam”  Rock Coating Detachment  Rounding of Glyph Edges  Scaling  Textural anomalies erode differently  Splintering  Other forms of incremental loss  Lith release of Wx- rind “dam”  Rock Coating Detachment  Rounding of Glyph Edges  Scaling  Textural anomalies erode differently  Splintering  Other forms of incremental loss

Loss of Stone by breaking-off chunks  Anthropogenic Activity  Fissuresol/cal crete wedging  Fire  Undercutting  Other natural causes of break- off

Rock Coatings & Other Deposits  Anthropogenic  Rock Coatings  Case Hardening*  Efflorescence/ Subflorescence  Anthropogenic  Rock Coatings  Case Hardening*  Efflorescence/ Subflorescence

Rock Coatings  Dust Coatings  Droppings  Heavy Metal  Iron Film  Lithobionts  Oxalate  Rock Varnish  Silica Glaze  Unclassified  Combinations of different types  Dust Coatings  Droppings  Heavy Metal  Iron Film  Lithobionts  Oxalate  Rock Varnish  Silica Glaze  Unclassified  Combinations of different types

South Mountain Municipal Park Box Canyon Central Entrance Metro-Phoenix (Granite)

Deer Valley Rock Art Center, Metro-Phoenix (Basalt)

Grand Canyon, Tanner Rapids (Sandstone)

Waterfall Canyon, Metro-Phoenix Whitetank Mountains (Granite)

Homolovi Ruins, Northern Arizona (Sandstone)

Tempe Butte Site (Andesite)