Siwa Oasis (Oasis Member, Marmarica Fm) (Miocene of Egypt)

Where: Egypt (29.2° N, 25.5° E: paleocoordinates 28.5° N, 24.7° E)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Oasis Member (Marmarica Formation), Middle Miocene (16.0 - 11.6 Ma)

• The Miocene succession fo the Siwa Depression can be subdivided into three units. The lowermost unit is the Oasis Member and consists of alternating carbonate beds and greenish, bluish, and blackish shales and marls. The carbonates are made up of cross-bedded coquina and other organoclastic limestones. Cross-bedding shows paleocurrent directions predominantly to the north and northwest. The Marmarica Formation is assigned a middle Miocene age and has a thickness of 78 m (256 ft).

• member-level stratigraphic resolution

Environment/lithology: shelly/skeletal limestone and black, green, blue shale

• The formation contains a rich neritic and reefal assemblage of invertebrate fossils and foraminifera.
• Consists of alternating carbonate beds and greenish, bluish, and blackish shales and marls. The carbonates are made up of cross-bedded coquina and other organoclastic limestone.

Size class: macrofossils

Collection methods: Collection data based on review of previously published literature.

Primary reference: E. E. Tawadros. 2001. Geology of Egypt and Libya 1-468 [A. Miller/A. Hendy/M. Clapham]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 42060: authorized by Austin Hendy, entered by Austin Hendy on 23.07.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Comprises taxa mentioned in text as typical of formation, including molluscs and forams. Page 145 of Tawadros (2001)
Echinoidea
 Clypeasteroida - Clypeasteridae
Clypeaster sp. Lamarck 1801 sand dollar
 Clypeasteroida - Scutellidae
Scutella sp. Lamarck 1816 sand dollar
 Echinolampadoida - Echinolampadidae
Echinolampas sp. Gray 1825 sea urchin