Fossil Leaves (Betula, Craigia, Metasequoia) and Petrified Wood (Stem/Branch Fragments)

Object/Artifact

-

Crater Rock Museum

Name/Title

Fossil Leaves (Betula, Craigia, Metasequoia) and Petrified Wood (Stem/Branch Fragments)

Entry/Object ID

07.57.13

Description

Light brown and tan base rock with three distinct fossil leaf impressions (two in upper right are Betula; third is Craigia?), a fruit/seed (Craigia oregonensis), stem and branch fragments (Metasequoia), and conifer needles (Metasequoia). Leaf fossils in this case are carbon films that remain on the bedding surfaces of fine-grained sediments. Fossilization happened after the leaves sank to the bottom of a pond or lake and were later buried by additional fine-grained sediments. With burial, the leaves were compressed and the sediment surrounding them solidified. Eventually these fine-grained sediments became sandstone, shale or mudstone. When all the volatile organic material in the living leaf was pressed out, only a thin carbon residue was left in the sediment, marking the outline and veins of the leaf. Clade: Tracheophytes Clade: Angiosperms Clade: Eudicots Clade: Rosids Order: Fagales Family: Betulaceae Subfamily: Betuloideae Genus: Betula Common Name: Birch Clade: Tracheophytes Clade: Angiosperms Clade: Eudicots Clade: Rosids Order: Malvales Family: Malvaceae Subfamily: Tilioideae Genus: Craigia Species: †C. oregonensis Clade: Tracheophytes Division: Pinophyta Class: Pinopsida Order: Pinales Family: Cupressaceae Subfamily: Sequoioideae Genus: Metasequoia Common Name: Dawn Redwood Rock and Mineral Data (Silica): Chemical Composition: Si O2 Crystal System: Hexagonal Type of Fossils Present: Plants Fracture: conchoidal Grain Size: Fine Hardness: 7 Quartz Luster: Glassy Occurrence: Pressure: Low-Moderate Rock Color: Medium Rock Origin: Post-depositional Rock Type: Sedimentary Specific Gravity: 2.6 Surface Process: Not apparent Temperature: Low Texture: Microcrystalline Variety: Petrified woods are hydrous microcrystalline varieties of quartz that can be generally termed as chalcedony or opalized .

Collection

Petrified Wood Collection

Acquisition

Accession

07.57

Source or Donor

Fossil Collection

Acquisition Method

Donation

Other Names and Numbers

Other Number

Other Number: 07.57.13

Dimensions

Width

3-3/4 in

Depth

1/4 in

Length

8 in

Dimension Notes

Dimension taken at widest points

Location

Location

Container

Center

Drawer

2nd Shelf

Shelf

Left

Cabinet

Case #111

Wall

South wall

Building

Mentzer Hall - Petrified Wood Room

Category

Permanent