PetrificationPetrification

Jen CowmanJen CowmanSakinah AlhabshiSakinah Alhabshi

CEE 367CEE 367Spring 2003Spring 2003

What is Petrification?What is Petrification?

The replacement of the normal cells of The replacement of the normal cells of organic matter with other mineralsorganic matter with other minerals

According to evolutionary doctrine, According to evolutionary doctrine, petrification requires much time, usually petrification requires much time, usually millions of years, but how much time is millions of years, but how much time is really needed in this process?really needed in this process?

Things are usually petrified in soil or by a Things are usually petrified in soil or by a water source with a high mineral contentwater source with a high mineral content

Affected by – temperature, pressure, Affected by – temperature, pressure, mineralsminerals

Mother Shipton’s Mother Shipton’s Petrifying WellPetrifying Well

Yorkshire, England

BackgroundBackground Available for public viewing since 1630 – Available for public viewing since 1630 –

cascades from River Nidd & forms an cascades from River Nidd & forms an aqueous curtain to Mother Shipton’s Caveaqueous curtain to Mother Shipton’s Cave

High mineral content:High mineral content: calcium, sodium and magnesiumcalcium, sodium and magnesium traces of lead, zinc, iron, manganese and traces of lead, zinc, iron, manganese and

aluminiumaluminium Exist mainly as sulphates and carbonates, Exist mainly as sulphates and carbonates,

with some chlorides and a trace of silicawith some chlorides and a trace of silica Proportions have remained more or less Proportions have remained more or less

regular over many yearsregular over many years

FactsFacts

As dissolved calcite (CaCOAs dissolved calcite (CaCO33) is exposed ) is exposed to air, COto air, CO22 escapes and the limestone is escapes and the limestone is depositeddeposited

2HCO2HCO33-- + Ca + Ca2+2+ CO CO2(g)2(g) + CaCO + CaCO3(s)3(s) + H + H22OO

Petrifies sponges/teddy-bears: 4-6 Petrifies sponges/teddy-bears: 4-6 months, Animals: 12-18 monthsmonths, Animals: 12-18 months

Flow of 700 gal/hrFlow of 700 gal/hr

Making a Profit?Making a Profit?

Souvenirs undergoing petrification to be sold to tourists – basket, teddy-bears, sponges, books,

gloves, foxes, cats, dogs, birds, and boots

EffectsEffects

Tufa – soft rockTufa – soft rock Travertine – hard Travertine – hard

rockrock Dark/light bandsDark/light bands The face of the rock The face of the rock

has to be scoured has to be scoured every 6 weeks to every 6 weeks to prevent it from prevent it from getting top heavy getting top heavy and falling over and falling over

Petrified Forest National Petrified Forest National Park Park

Petrified Wood, Arizona

RequirementsRequirements

The dead wood needs to be protected The dead wood needs to be protected from decayfrom decay

The dead wood becomes saturated The dead wood becomes saturated with mineral-laden waterwith mineral-laden water

The porous nature of wood allows the The porous nature of wood allows the movement of water-borne particlesmovement of water-borne particles

The water itself needs to harbor The water itself needs to harbor specific minerals necessary for specific minerals necessary for petrificationpetrification

How?How?

After burial and saturation, After burial and saturation, chemical reactions take place chemical reactions take place between the minerals and the between the minerals and the cellulose compounds in the cell cellulose compounds in the cell wallswalls

Mineral crystals grow in the Mineral crystals grow in the spaces left behind by the spaces left behind by the dissolution of the cell wallsdissolution of the cell walls

Two phases of crystal deposition Two phases of crystal deposition result in complete mineral result in complete mineral replacement of the woodreplacement of the wood

Cross-section, cell walls infiltrated by quartz.  X350

Colors?Colors? Minerals - iron, manganese, Minerals - iron, manganese,

carbon, and chromium, cause carbon, and chromium, cause the colors of the petrified the colors of the petrified woodwood

Red – ironRed – iron Green – chromiumGreen – chromium Black – carbon / magnetiteBlack – carbon / magnetite

Yellowstone National Yellowstone National ParkPark

Continental “hot spot” in Wyoming Continental “hot spot” in Wyoming Mammoth Hot Spring TerracesMammoth Hot Spring Terraces

100 hot springs scattered over terraces100 hot springs scattered over terraces Thermal springs deposit CaCOThermal springs deposit CaCO33 as as

travertine between 2.8 – 56.5 cm/yeartravertine between 2.8 – 56.5 cm/year Silica deposition rates into blocks of Silica deposition rates into blocks of

wood in alkaline springs at Yellowstone wood in alkaline springs at Yellowstone between 0.1 and 4.0 mm/yr between 0.1 and 4.0 mm/yr

Liberty CapLiberty Cap

Liberty CapLiberty Cap 45 ft tall45 ft tall Cone formed from a Cone formed from a

steady flow of hot steady flow of hot water from a single water from a single sourcesource

Presently inactivePresently inactive

Opal TerraceOpal Terrace Opal Terrace Opal Terrace

160° F160° F Known for its pastel colorsKnown for its pastel colors A tennis court had to be removed because it A tennis court had to be removed because it

grew too quicklygrew too quickly

New Highland TerraceNew Highland Terrace

TerracetteTerracette Semicircular ledge Semicircular ledge

formed by travertine formed by travertine that is deposited that is deposited around slowly rising around slowly rising poolspools

Hot water flows over Hot water flows over the lip and forms the lip and forms stalactitesstalactites

““Instant” Petrified Instant” Petrified WoodsWoods

Advanced Ceramic Labs at the University of Advanced Ceramic Labs at the University of Washington, SeattleWashington, Seattle

Wood-ceramic composites 20–120% harder Wood-ceramic composites 20–120% harder than regular woodthan regular wood

Simple process – soak wood in silicon and Simple process – soak wood in silicon and aluminium solution, then oven-cure at 44°C aluminium solution, then oven-cure at 44°C (112°F)(112°F)

Hamilton Hicks, Connecticut – made a Hamilton Hicks, Connecticut – made a chemical 'cocktail' of sodium silicate, natural chemical 'cocktail' of sodium silicate, natural spring or volcanic mineral water - high spring or volcanic mineral water - high content of calcium, magnesium, manganese content of calcium, magnesium, manganese and other metal salts, and citric or malic acidand other metal salts, and citric or malic acid

Potential Uses for Potential Uses for “Instant” Petrified Woods“Instant” Petrified Woods

Fireproofing wooden structureFireproofing wooden structure Longer-wearing floors and furnitureLonger-wearing floors and furniture Greater strength woodGreater strength wood Insect, decay and salt-water proof Insect, decay and salt-water proof

wood in buildingswood in buildings

ConclusionsConclusions

Misconception: fossilized wood Misconception: fossilized wood buried in rock strata must have buried in rock strata must have taken thousands, if not millions, of taken thousands, if not millions, of years to petrify years to petrify

Can be rapid Can be rapid Good knowledge base – we can make Good knowledge base – we can make

petrified wood for our benefitpetrified wood for our benefit