DX5 Sample 4: Llandovery, Iowa

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
unclassified
Psuedolonchodina sp.
8 elements
Conodonta - Prioniodontida
Oulodus sp. Branson and Mehl 1933
2 elements
Conodonta - Prioniodontida - Balognathidae
Pterospathodus amorphognathoides Walliser 1964
4 elements
Subspecies"Pterospathodus amorphognathoides angulatus"
Conodonta - Prioniodontida - Distomodontidae
Distomodus staurognathoides (Walliser 1964)
1 element
Conodonta - Prioniodontida
Pseudooneotodus beckmanni (Bischoff and Sannemann 1958)
1 element
Conodonta - Panderodontida - Panderodontidae
Panderodus sp. Ethington 1959
7 elements
Panderodus equicostatus (Rhodes 1953)
32 elements
Panderodus unicostatus (Branson and Mehl 1933)
36 elements
original and current combination Paltodus unicostatus
Panderodus panderi (Stauffer 1940)
9 elements
Conodonta - Ozarkodinida - Spathognathodontodae
Ozarkodina polinclinata (Nicoll and Rexroad 1968)
4 elements
recombined as Wurmiella polinclinata
Subspecies"Ozarkodina polinclinata polinclinata"
see common names

Geography
Country:United States State/province:Iowa
Coordinates: 42.1° North, 91.1° West (view map)
Paleocoordinates:20.1° South, 56.7° West
Basis of coordinate:estimated from map
Time
Period:Silurian Epoch:Llandovery
10 m.y. bin:Silurian 1
Key time interval:Llandovery Conodont zone: Pterospathodus celloni
Age range of interval:443.80000 - 433.40000 m.y. ago
Stratigraphy
Formation:LaPorte City
Stratigraphy comments: Sample (m) 3,49-3,59
Lithology and environment
Primary lithology: lithified "limestone"
Lithology description: The base of the LPC is equivalent to the uppermost part of the lower Hopkinton member, and is composed mainly of breccia beds with chert and large limestone interclasts in a slightly sandy mud matrix. The portion of the LPC equivalent to the Farmers Creek Quarry Member contains brecciated chert beds, a bio-dolo-mud- to wackestone with crinoid debris, and bio-mud- to packstones. Chert nodules are scattered throughout. The portion of the LPC equivalent to the Picture Rock Member of the Hopkinton Formation is a green, calcareous shale to mudstone, and the remainder are bio-wacke- to packstones. The portion of the LPC equivalent to the BCQ Member of the Scotch Grove Formation is composed of predominantly mudstones with scattered crinoid debris punctuated by occasional bio-wacke- to packstones with crinoid debris and brachiopod fossils. There are some intervals of argillaceous mudstones and calcareous green shales that are more predominant in the middle of the BCQ equivalent in the GC. The BCQ is exposed at the base of the DX5 outcrop and is a bio-dolo-wackestone with occasional chert nodules. The base of the LPC is marked by thinly bedded chert, overlain by a bed of slightly dolomitized crinoidal wackestone with chert nodules (Figure 6).
Environment:carbonate indet.
Taphonomy
Modes of preservation:body
Size of fossils:microfossils
Collection methods and comments
Reason for describing collection:biostratigraphic analysis
Metadata
Database number:191083
Authorizer:E. Jarochowska Enterer:S. Haegele
Modifier:S. Haegele Research group:micropaleontology,vertebrate
Created:2018-01-08 15:26:59 Last modified:2018-01-08 15:31:15
Access level:authorizer only Released:2020-01-08 15:26:59
Creative Commons license:CC BY
Reference information

Primary reference:
63246. C. B. T. Waid and B. D. Cramer. 2017. Telychian (Llandovery, Silurian) conodonts from the LaPorte City Formation of eastern Iowa, USA (East-Central Iowa Basin) and their implications for global Telychian conodont biostratigraphic correlation. Palaeontologia Electronica 20(2):1-37 [P. Wagner/P. Wagner]