Al Khums Formation (Miocene of Libya)

Where: Libya (30.5° N, 13.5° E: paleocoordinates 30.0° N, 12.8° E)

• coordinate stated in text

• basin-level geographic resolution

When: Al Khums Formation, Middle Miocene (16.0 - 11.6 Ma)

• LITHOSTRATIGRAPHIC RELATIONSHIPS: From the Al Khums Fm, for which lithostratigraphic relationships are unknown. AGE: Middle Miocene, on the basis of microfossil and macrofossil biostratigraphy. THICKNESS: ranges from 5 to 100 m across its range.

• formation-level stratigraphic resolution

Environment/lithology: lagoonal or restricted shallow subtidal; poorly lithified, shelly/skeletal, green, yellow marl and poorly lithified, white limestone

• ENVIRONMENT: Shallow neritic environment of deposition with lagoonal facies.
• GENERAL LITHOLOGY: Greenish-yellow gypsiferous marls with pelecypods, intercalations of white limestone, occasionally saccaroidal and silicified, and greenish-gray marls. LITHIFICATION: Lithified, assumed on the basis of facies description.

Size classes: macrofossils, microfossils

Collection methods: surface (in situ),

• COLLECTORS: Not stated, possibly multiple collectors. REPOSITORY: Unknown.

Primary reference: M. F. Megerisi and V. D. Mamgain. 1980. The Upper Cretaceous-Tertiary Formations of northern Libya: a synthesis. Department of Geological Researches and Mining Bulletin 12:1-85 [A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 77254: authorized by Austin Hendy, entered by Austin Hendy on 07.01.2008

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Limited, but including bivalvia, gastropoda, echinoids, algae, and foraminifera. NOMENCLATURE: Somewhat antiquated nomenclature, but identified to species and subgenus resolution.
Show authors, comments, and common names
unclassified
  -
Illyocypris sp.
Gastropoda
 Cerithioidea - Turritellidae
Turritella sp.
Turritella sp. Lamarck 1799 turret shell
 Neogastropoda - Conidae
Conus sp.
Conus sp. Linnaeus 1758 cone shell
 Sorbeoconcha - Cypraeidae
Cypraea sp.
Cypraea sp. Linnaeus 1758 cowry
 Sorbeoconcha - Naticidae
Natica sp.
Natica sp. Scopoli 1777 moon snail
Bivalvia
 Ostreida - Ostreidae
Ostrea frondosa, Crassostrea sp., Crassostrea gigensis
Ostrea frondosa de Serres 1829 oyster
Crassostrea sp. Sacco 1897 oyster
 Pectinida - Pectinoidae
Pecten sp., Chlamys sp.
Pecten sp. Müller 1776 scallop
Chlamys sp. Röding 1798 scallop
 Pectinida - Limidae
Lima sp.
Lima sp. Bruguière 1797 file clam
 Cardiida - Cardiidae
Cardium sp.
Cardium sp. Linnaeus 1758 cockle
 Cardiida - Veneridae
Pitaria sp.
Pitaria sp. Roemer 1857 venus clam
Ostracoda
 Podocopida - Cyprididae
Cypridopsis sp.
Cypridopsis sp. Brady 1868 ostracod
 Podocopida - Limnocytheridae
Paralimnocythere sp.
Paralimnocythere sp. Carbonnel 1965 ostracod
Florideophyceae
  - Corallinophycidae
"Lithothamnium sp." = Lithothamnion, Lithophyllum sp.
"Lithothamnium sp." = Lithothamnion Heydrich 1897
Lithophyllum sp. Philippi 1837
Foraminifera
  -
Miogypsinoides cf. deharti
 Rotalioidea - Elphidiidae
Elphidium macellum, Elphidium crispum, Elphidium flexuosum, Elphidium minutum
 Globigerinoidea - Globorotaliidae
"Globorotalia menardii" = Globorotalia (Menardella) menardii, "Globorotalia praemenardii" = Globorotalia (Menardella) praemenardii
"Globorotalia menardii" = Globorotalia (Menardella) menardii Parker et al. 1865
"Globorotalia praemenardii" = Globorotalia (Menardella) praemenardii Cushman and Stainforth 1945
 Rotaliacea - Rotaliidae
Ammonia beccari
Tubothalamea
 Miliolida - Alveolinidae
Borelis melo
Borelis melo
SUBSPECIES: B. melo curdica
 Charales - Feistiellaceae
Nitellopsis (Tectochara) sp.
Psilochara
  -
Psilochara sp.
Psilochara sp. Grambast 1959