Inequigranular limestone 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) equigranular limestone facies; 8) INEQUIGRANULAR LIMESTONE FACIES.

• group of beds-level stratigraphic resolution

Environment/lithology: lithified, shelly/skeletal limestone

• uigNo paleoenvironmental data reported.
• This facies is an inequigranular, clastic limestone, very well-indurated, characteristically massive, and indistinctly bedded. relatively pure, and foraminiferal.

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 43371: 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.
Chlorophyceae
 Dasycladales - Dasycladaceae
Cymopolia sp. Lamouroux 1816
Ulvophyceae
 Bryopsidales - Halimedaceae
Halimeda sp. Lamouroux 1812
Anthozoa
 Helioporacea -
 Scleractinia - Acroporidae
Astreopora sp. Blainville 1830 stony coral
 Scleractinia - Agariciidae
Trochoseris florescens Felix 1921 stony coral
Leptoseris floriformis Gerth 1923 stony coral
Gastropoda
 Trochoidea - Trochidae
Trochus sp. Linnaeus 1758 top snail
 Cerithioidea - Turritellidae
"Turritella cf. spolongensis" = Turritella (Archimediella) spolongensis, "Turritella cf. javana" = Zaria javana
"Turritella cf. spolongensis" = Turritella (Archimediella) spolongensis Martin 1916 turret shell
"Turritella cf. javana" = Zaria javana Martin 1882 turret shell
 Sorbeoconcha - Strombidae
Strombus sp. Linnaeus 1758 conch
 Sorbeoconcha - Vermetidae
Vermetus sp. Daudin 1800 worm shell
Bivalvia
 Arcida - Arcidae
Acar domingensis Lamarck 1819 miniature ark
 Pectinida - Pectinoidae
Spondylus sp. Linnaeus 1758 scallop
 Mytilida - Mytilidae
"Lithophagus sp." = Modiola (Lithophagus)
"Lithophagus sp." = Modiola (Lithophagus) Megerle 1811 mussel
 Cardiida - Chamidae
"Echinochama sp." = Arcinella
"Echinochama sp." = Arcinella Schumacher 1817 jewel box
 Cardiida - Veneridae
"Venus (Chione) listeri" = Periglypta listeri
"Venus (Chione) listeri" = Periglypta listeri Gray 1838 venus clam
 Cardiida - Cardiidae
"Cardium (Fragum) javanum" = Fragum
"Cardium (Fragum) javanum" = Fragum cockle
 Cardiida - Tellinidae
Tellina sp. Linnaeus 1758 tellin clam
 Solenida - Pharidae
Ensis sp. Schumacher 1817 clam
Echinoidea
 Camarodonta - Parasaleniidae
Parasalenia sp. n. sp. sea urchin
 Spatangoida - Schizasteridae
Schizaster sp. n. sp. Agassiz 1835 heart urchin
 Clypeasteroida - Fibulariidae
"Sismondia polymorpha" = Echinocyamus polymorpha
"Sismondia polymorpha" = Echinocyamus polymorpha Duncan and Sladen 1883 sand dollar
Subspecies: Sismondia polymorpha = S. convexa (Nisiyama)