absolute dating- dating fossils and rocks by determining radioactivity by certain elements 

basin- bowl-shaped depression on land or on the ocean floor into which sediments may be deposited

calcite- the common mineral found in fossils

chalcedony-  a translucent or grayish form of quartz in which the microscopic crystals are packed together in parallel bands, used as a gemstone and in ornaments. SiO2

Chinle formation- a striation comprised of siltstone, sandstone, and clay. 

clay- formed from decomposing volcanic ash. 

conglomerate- rock composed of rounded, water-worn fragments of older rock with sand in between 

decay- to decompose, or make something decompose, and become soft, crumbly, or liquefied

decomposed- to break something down, or be broken down, into smaller or simpler parts

flora- plants

formations-  a sedimentary bed or series of beds 

fossil- the remains of a living thing 

fossilization- to convert something into a fossil, to preserve something as a fossil, or to become a fossil

geology-  the study of rocks, minerals, and physical structure of a particular area

half life- the time a radioactive substance takes to lose half its radioactivity through decay. Symbol T½

hydrous microcystalline- gelled water and silicon dioxide

limestone- a sedimentary rock consisting (made up of) predominately of calcium carbonate

minerals- natural solids formed from elements and compounds in the earth’s crust

opal- a form of silicon dioxide; hydrated silica, softer than quartz and more fragile than chalcedony 

paleobotany- is the study of fossilized flora

percolate- to pass slowly through something or spread throughout a place

permeate- permitting the movement of fluids or gases through it by way of pores or other passages

permineralization- Permineralization occurs when mineral matter fills in the void and pore spaces within the original organic structure. The mineral that fills in the pores is sometimes the same as the biomineral, although not always. Infilling by calcite, aragonite, iron oxide, silica, and other common inorganic cements are usual, although deposition of other, more unusual minerals is also known.

petrified- the completion of permineralization or the replacement of normal cells with minerals of organic matter with silica or other minals 

petrification- occurs when the organic matter is completely replaced by minerals and the fossil is turned to stone. This generally occurs by filling the pores of the tissue, and inter and intra cellular spaces with minerals, then dissolving the organic matter and replacing it with minerals. This method reproduces the original tissue in every detail. This kind of fossilization occurs in both hard and soft tissues. An example of this kind of fossilization is petrified wood.

petros-stone 

porous- easy to cross, infiltrate, or penetrate

quartz- a crystalline form of silica

recrystallization- Recrystallization is the solid state transformation of a mineral to a new crystal form (not always the same mineral). The new crystals usually obscure the original fine structural detail. The bulk elemental composition does not change in this transformation. 

relative age- looking at striations and determining which is older by location 

replacement-  Preservation by replacement involves the substitution of an inorganic mineral for the original biomineral or tissue. While fine scale preservation is possible, replacement usually obliterates very fine structures. The final mineralogy of the fossil may or may not differ in bulk composition from the original. 

sandstone- sedimentary rock formed from silt with particles larger than silt

sedimentary rock - rock that forms from pieces of other rocks or the remains of once living things

silica- silicon dioxide

silification- turned into silica

siltstone- sedimentary rock formed from silt with particles smaller that sand grains and clay

striations- layers of sediment within sedimentary rock

variables - the five components involved in the petrification process