Malone Mountains and outlying foothills, Upper Malone Formation: Early Berriasian, Texas

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Cephalopoda - Ammonitida - Neocomitidae
Kossmatia aguilerai
Kossmatia zacatecana Burckhardt 1912
Bivalvia - Ostreida - Gryphaeidae
Exogyra potosina
see common names

Geography
Country:United States State/province:Texas
Coordinates: 31.2° North, 105.6° West (view map)
Paleocoordinates:28.1° North, 56.0° West
Basis of coordinate:based on nearby landmark
Geographic resolution:local area
Time
Period: Cretaceous Epoch: Early Cretaceous
Stage: Berriasian 10 m.y. bin: Cretaceous 1
Key time interval: Early Berriasian
Age range of interval: 145 - 142.7 m.y. ago
Stratigraphy
Formation:Malone Member:Upper
Stratigraphic resolution:member
Stratigraphy comments: "Malone formation... the formation consits of two divisions. The upper division (330 ft) is composed dominantly of impure limestones... [Fauna] fixing the age of the upper division as upper Portlandian." (according to Sey and Kachaleva 1999 Upper Volgian (Upper Portlandian) = Lower Berriasian)
Lithology and environment
Primary lithology:fine lithified "limestone"
Environment:lagoonal/restricted shallow subtidal
Geology comments: Classification based on the following description: "...the lower and upper members of the Malone Formation are raised to formation status and called the Broadtop Hill Formation and Cedar Canyon Formation, respectively, in order to reflect their true lithologic character. The Cedar Canyon Formation consists of mudstones and wackestones deposited in a brackish lagoonal environment. Both marine and freshwater algae are the predominant fossil types." cited from B. Tickner (2005). Stratigraphic studies and microfacies analysis of the Jurassic succession, Malone Mountains, west Texas.
Taphonomy
Size of fossils:macrofossils
Collection methods and comments
Collection excludes:some macrofossils
Collection methods:field collection
Reason for describing collection:biostratigraphic analysis
Collection method comments: collected in the summers of 1934 and 1935
Taxonomic list comments:"The lists of fossils are not complete for any of the three formations. The particular species entered are chosen either because their age has been subject of controversy, or, because they are important in the dating of formations, or, because they are unusually abundant in their respective formations."
Metadata
Database number:69011
Authorizer:M. Aberhan Enterer:S. Nurnberg
Modifier:S. Nurnberg Research group:marine invertebrate
Created:2007-02-15 05:46:43 Last modified:2007-02-20 04:45:33
Access level:the public Released:2007-02-15 05:46:43
Creative Commons license:CC BY
Reference information

Primary reference:
19914.1% C. C. Albritton. 1937. Faunal diversity in Malone Mountains beds, Texas. Pan-American Geologist 68(4):257-262 [M. Aberhan/S. Nurnberg]