Marks (1951) IPC# 1464 (Blue Siltstone Mbr, Daule Fm) (Miocene of Ecuador)

Where: Guayas, Ecuador (1.7° S, 80.3° W: paleocoordinates 2.5° S, 77.3° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Blue Siltstone Member (Daule Formation), Middle Miocene (16.0 - 11.6 Ma)

• From Daule Fm, which is of Middle Miocene age comprises three members, a "basal calcareous" member, a middle "blue siltstone" member, and an "upper calcareous" member. The exact thickness of the unit has not been measured accurately in this section because of structural complications. The blue siltstone, from which this collecion is derived is about 800 ft thick. Faunal compositions suggests a Middle Miocene age, with affinities to the Progreso Fm, and Middle Miocene formations of Peru. Taxa are share with the Gatun fm, the Tubera Fm, the Cucurrupi Fm of Colombia.

• bed-level stratigraphic resolution

Environment/lithology: offshore; poorly lithified, blue siltstone

• Deposition at slightly greater depth, quiet conditions, several kilometers from shore, siliciclastic environment, with normal salinity conditions, during relative highstand.
• Recessive blue siltstone

Size class: macrofossils

Reposited in the PRI

Collection methods: quarrying,

• Fossil material derived from the International Ecuadorian Petroleum Company (subsidiary of Standard Oil Co.) and was collected by the author (then employed by oil company) during field exploration and drilling operations. All type and voucher material reposited in PRI collections.

Primary reference: J. G. Marks. 1951. Miocene stratigraphy and paleontology of Southwestern Ecuador. Bulletins of American Paleontology 33(139):1-448 [A. Miller/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 61086: authorized by Austin Hendy, entered by Austin Hendy on 29.05.2006

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for gastropoda and bivalvia.
Gastropoda
 Sorbeoconcha - Naticidae
"Natica guppyana" = Stigmaulax guppiana
"Natica guppyana" = Stigmaulax guppiana Toula 1909 moon snail
 Sorbeoconcha - Cypraeidae
Muracypraea woodringi Landau and Groves 2011 cowry
Cypraea sp. Linnaeus 1758 cowry
 Neogastropoda - Conidae
Conus bravoi, "Conus sophus" = Conus imitator sophus, "Conus multiliratus" = Conasprelloides multiliratus
Conus bravoi Spieker 1922 cone shell
"Conus sophus" = Conus imitator sophus Olsson 1932 cone shell
"Conus multiliratus" = Conasprelloides multiliratus Olsson 1922 cone shell
 Neogastropoda - Clavatulidae
Turricula sp. Schumacher 1817 snail
 Neogastropoda - Columbellidae
"Strombina striatocostata" = Strombina (Strombina) colinensis
"Strombina striatocostata" = Strombina (Strombina) colinensis Hodson 1931 snail
 Neogastropoda - Buccinidae
"Cantharus predistortus" = Nicema predistorta, Phos haughti, Hanetia sp.
"Cantharus predistortus" = Nicema predistorta Marks 1951 true whelk
Phos haughti Marks 1951 true whelk
Hanetia sp. Jousseaume 1880 true whelk
 Neogastropoda - Cancellariidae
"Cancellaria casicalva" = Pyruclia casicalva
"Cancellaria casicalva" = Pyruclia casicalva Marks 1949 snail
 Heterostropha - Architectonicidae
Architectonica nobilis Röding 1798 sundial
Bivalvia
 Carditida - Crassatellidae
Eucrassatella berryi Spieker 1922 clam
 Cardiida - Veneridae
"Clementia dariena" = Clementia (Clementia) dariena
"Clementia dariena" = Clementia (Clementia) dariena Conrad 1855 venus clam