The Dam Formation is an Early Miocene formation located in southwestern Qatar,[2] Saudi Arabia and the UAE.[3]
| Dam Formation | |
|---|---|
| Stratigraphic range: Early Miocene ~ | |
 The location of the Dam formation in Qatar (dark and light blue dots) | |
| Type | Geological formation |
| Sub-units | Al-Kharrara Member, Al-Nakhsh member, Abu Samrah member |
| Underlies | Dammam Formation |
| Overlies | Hofuf Formation |
| Lithology | |
| Primary | Silicate, dolomite and calcite |
| Other | Celestine, chlorite, gypsum, kaolinite, muscovite, illite, palygorskite, and smectite[1] |
| Location | |
| Country | Qatar, Saudi Arabia, UAE |
| Type section | |
| Named by | Steineke and Kock (unpublished), Powers (in Saudi Arabia), Cavelier (in Qatar) |
| Year defined | 1935 (unpublished), 1968 (Saudi Arabia), 1970 (Qatar) |
| Coordinates | 26°21′42″N 49°27′42″E / 26.36167°N 49.46167°E |
| Country | Qatar, Saudi Arabia, United Arab Emirates |
  Dam Formation (Saudi Arabia) | |
Description
editThe formation was first described in a report in 1935 by Steineke and Kock. However, this report was unpublished. It was first described in published material by Powers in 1968 in Saudi Arabia, and by Cavelier in 1970 in Qatar.[3]
The formation in Saudi Arabia and the U.A.E. was deposited in a terrestrial environment, while the formation in Qatar was deposited in a marine habitat as evidenced by the multiple marine animals found in the formation.[2][3]
Fossil content
edit| Mammals from the Dam formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Salwasiren | S. qataernsis[2] | ARC.2023.23.008, one associated skeleton including an incomplete cranium, mandible, left upper molar (M2), sternum, both scapulae and humeri, a partial vertebral column and ilium. | A dugongid sireanian | Lower Al-Kharrara Member | .jpg) |
| Odontoceti | Indeterminate[2][3] | A tooth[3] among other remains | Lower Al-Kharrara Member | ||
| Fishs from the Dam formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Teleost | Indeterminate[2] | Lower Al-Kharrara Member | |||
| Carcharhiniformes | Indeterminate[2] | ||||
| Physodon/Scoliodon[3] | P./S.sp. | ||||
| Aetobatus | A.arcuatus[3] | A species of Eagle ray | |||
| Diodon[3] | D.sp. | A species of porcupine fish | |||
| Reptiles from the Dam formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Testudines | Indeterminate[2][3] | Lower Al-Kharrara Member | |||
| Reptillia? | Indeterminate[3] | Lower/Middle Al-Kharrara Member | |||
| Molluscs from the Dam formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Ostrea[3] | O.latimarginata | Bivalve | Lower & Middle Al-Kharrara Members | ||
| Pectinidae[3] | Indeterminate | Scallop | |||
| Anomia[3] | Indeterminate | Bivalve | |||
| Spondylus[3] | |||||
| Avicula[3] | |||||
| Clementia[3] | C.papayracea | "Impressions and molds" | Lower, Middle & Upper Al-Kharrara Members & Abu Samrah member | ||
| Chama[3] | C. gryphoides | ||||
| Clausinella[3] | C.erisca | Bivalve | |||
| C. persica | |||||
| Hydrobiidae[3] | Indeterminate | A family of fresh to brackish water snails | |||
| Chlamys[3] | C.senatoria | Bivalve | Upper Al-Kharrara Member & Abu Samrah member | ||
| Fissurella[3] | Indeterminate | Gastropod | |||
| Natica[3] | |||||
| Xenophora[3] | |||||
| Turritella[3] | |||||
| Cerithiidae[3] | |||||
| Conus[3] | |||||
| Bulla[3] | |||||
| Hydrobia[3] | Gastropod "Very locally" found | ||||
| Potamides[3] | |||||
| Capsa[3] | C. lacunosa | ||||
| cf. C. fragilis | |||||
| Tellina[3] | T. bipartita | Bivalve | |||
| Diplodonta[3] | D.cf. rotundata | ||||
| Barbatia[3] | B. barbata | Bivalve | |||
| Anadara[3] | A.cf. turonica | ||||
| Cardiocardita[3] | C.cf. monolifera | ||||
| C.aff. turonica | |||||
| Solecurtus[3] | S. basteroti | ||||
| Timoclea[3] | T. subspadicea | ||||
| Musculus[3] | M.sp. | Bivalve | |||
| Eastonia[3] | Indeterminate | ||||
| Panopea[3] | Gastropod | ||||
| Tapes[3] | Bivalve | ||||
| Mactra[3] | |||||
| Lucina[3] | |||||
| Cardium[3] | |||||
| ?Olivella[3] | Remains of "Internal molds" | ||||
| Voluta[3] | |||||
| Fasciolaria[3] | |||||
| Cassis[3] | |||||
| Cypraea[3] | |||||
| Echinoderms from the Dam formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| Fibularia[3] | F. damensis | A Sand Dollar | |||
| Agassizia[3] | A. aff. persica | Sea urchin | |||
| Cidaris[3] | C.sp. | Spines | |||
| Bryozoans from the Dam formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Material | Notes | Member | Images |
| ?Cupuladria[3] | C. gr. haidingeri | ||||
Crustacean remains have also been found in the formation[3]
References
edit- ↑ "Al-Nakhsh Member, Dam Formation, Qatar". www.mindat.org. Retrieved 2026-01-13.
- 1 2 3 4 5 6 7 8 Pyenson, Nicholas D.; Sakal, Ferhan; LeBlanc, Jacques; Blundell, Jon; Klim, Katherine D.; Marshall, Christopher D.; Velez-Juarbe, Jorge; Wolfe, Katherine; Al-Naimi, Faisal (2025-12-10). "High abundance of Early Miocene sea cows from Qatar shows repeated evolution of seagrass ecosystem engineers in Eastern Tethys". PeerJ. 13 e20030. doi:10.7717/peerj.20030. ISSN 2167-8359. PMC 12701702. PMID 41394419.
- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 LeBlanc, Jacques (2021-10-22). "Stratigraphic Lexicon: A revised guide to the Cenozoic Surface Formations of Qatar, Middle East (excluding the islands)". Biosis: Biological Systems. 2 (4). doi:10.37819/biosis.001.04.0134. ISSN 2707-9783.