Marly facies (Tagpochau Limestone), Saipan, Mariana Islands (Miocene of Northern Mariana Islands)

Where: Northern Mariana Islands (15.2° N, 145.8° E: paleocoordinates 15.2° N, 148.0° E)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Tagpochau Formation, Early/Lower Miocene (23.0 - 16.0 Ma)

• The Tagpochau Limestone is a complex of calcareous clastic rocks that integrade with one another. The limestone appears to span the Indonesian Tertiary e interval or early Miocene age. Six lithic facies and two members are recognized in the Tagpochau Limestone, and include: 1) Donni Sandstone Member; 2) Machegit conglomerate Member; 3) transitional facies of calcareous tuff and marl; 4) tuffaceous limestone facies; 5) MARLY FACIES; 6) rubbly limestone facies; 7) equigrannular limestone facies; 8) inequigranular limestone facies. The collection is from the Donni Sandstone member occurs near the middle of the formation.

• group of beds-level stratigraphic resolution

Environment/lithology: lithified, fine-grained, brown, white, yellow, argillaceous, calcareous limestone

• No paleoenvironmental data reported.
• Impure limestones, characterised by argillaceous material, moderate induration, tan to yellowish-white, or yellow-orange color, mostly fine-grained, and well stratified.

Size class: macrofossils

Collection methods: quarrying,

• Collections probably reposited in USNM collections, but this is not stated.

Primary reference: P. E. Cloud, Jr, R.G. Schmidt, and H.W. Burke. 1956. Geology of Saipan, Mariana Islands: Part 1. General Geology. United States Geological Survey Professional Paper 280(A):1-126 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 43368: authorized by Austin Hendy, entered by Austin Hendy on 12.08.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for mollusca, echinoidea, corals, and calcareous algae are also included. Foraminifera are listed but not included in collection. Identifications of mollusca by J. Gardner, echinoids by C.W. Cooke, corals by J.W. Wells.
Bivalvia
 Arcida - Arcidae
Acar domingensis Lamarck 1819 miniature ark
 Pectinida - Pectinoidae
"Chlamys (Aequipecten) exageratus" = Aequipecten
"Chlamys (Aequipecten) exageratus" = Aequipecten scallop
 Lucinida - Lucinidae
Parvilucina sp. Dall 1901 clam
 Cardiida - Cardiidae
"Cardium (Fragum) javanum" = Fragum
"Cardium (Fragum) javanum" = Fragum cockle
Gastropoda
 Sorbeoconcha - Strombidae
? Strombus sp. Linnaeus 1758 conch
 Sorbeoconcha - Cypraeidae
Cypraea sp. Linnaeus 1758 cowry
 Neogastropoda - Muricidae
Murex sp. Linnaeus 1758 murex snail
 Sorbeoconcha - Xenophoridae
Xenophora sp. Fischer von Waldheim 1807 carrier shell
 Cerithioidea - Cerithiidae
 Cerithioidea - Turritellidae
"Turritella cf. spolongensis" = Turritella (Archimediella) spolongensis, "Turritella cf. javana" = Zaria javana, "Turritella ? sedanensis" = Haustator sedanensis
"Turritella cf. spolongensis" = Turritella (Archimediella) spolongensis Martin 1916 turret shell
"Turritella cf. javana" = Zaria javana Martin 1882 turret shell
"Turritella ? sedanensis" = Haustator sedanensis Martin 1905 turret shell
Echinoidea
 Clypeasteroida - Fibulariidae
"Sismondia polymorpha" = Echinocyamus polymorpha
"Sismondia polymorpha" = Echinocyamus polymorpha Duncan and Sladen 1883 sand dollar
= S. convexa (Nisivama)
 Echinolampadoida - Echinolampadidae