Alnus (Alder Leaf)

Object/Artifact

-

Crater Rock Museum

Name/Title

Alnus (Alder Leaf)

Entry/Object ID

07.57.04

Description

Alder leaf imprint on a beige sandstone. 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: Alnus Common name: Alder Leaf Rock and Mineral Data (Silica): Chemical Composition: Si O2 Crystal System: Subhedral Fracture: conchoidal Grain Size: Fine Hardness: 7 Quartz Luster: Silky Occurrence: Lithofacies: sedimentary Assemblage Zone: sandstone Type of Fossils Present: Plants Pressure: Moderate Rock Color: Dark Rock Origin: Marine/Freshwater Rock Type: Sedimentary Specific Gravity: 2.6 Surface Process: Not apparent Temperature: Low Texture: fine grain Variety:

Collection

Fossil Collection

Acquisition

Accession

07.57

Source or Donor

Fossil Collection

Acquisition Method

Donation

Notes

This entry does not fit with the details on 07.57.04 in the physical catalog. They seem to describe two entirely different specimens. I have left this as is, and created a new 07.57.4 catalog entry for the information present in the original catalog (or inventory sheet?).

Other Names and Numbers

Other Number

Other Number: 2007.57.04

Dimensions

Width

3 in

Length

2 in

Dimension Notes

Dimensions taken at widest points

Location

Location

Shelf

2nd left, 2nd left

Wall

North

Room

Wood room

Building

Mentzer Hall - Petrified Wood Room

Category

Permanent

Moved By

Catherine Boyd

Date

August 23, 2008

Location

Drawer

Left

Shelf

2nd Shelf

Cabinet

Case #105

Wall

North

Room

Wood room

Building

Mentzer Hall - Petrified Wood Room

Category

Permanent