Bet-Meir Formation
Geologic formation in the West Bank
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The Bet-Meir Formation is a Late Cretaceous sedimentary unit exposed in the central highlands of the West Bank (Palestine).[2] It belongs to the regional Judea Group and records sedimentation on a broad, shallow marine carbonate platform along the southern margin of the Tethys Ocean during the Early Cenomanian.[2][3]
| Bet-Meir Formation | |
|---|---|
| Stratigraphic range: Late Cretaceous (Cenomanian) | |
Bet-Meir formation at Shomron | |
| Type | Geological formation |
| Unit of | Judea Group |
| Underlies | Amminadav Formation |
| Overlies | Kesalon Formation |
| Area | West Bank |
| Thickness | Up to 60 m |
| Lithology | |
| Primary | Dolostone |
| Other | Chalk, limestone, marl |
| Location | |
| Region | Judea and Samaria |
| Country |  Palestine[1] |
| Extent | Palestine (Judea and Samaria), west of Hebron, near Jericho |
| Type section | |
| Named for | Bet Meir |
| Named by | Itzhaki et al., 1964 |
The formation is paleontologically significant. Vertebrate remains recovered from it include pterosaurs, several species of ray-finned fish, and early snakes. Many important specimens come from quarries near Ein Yabrud, north and east of Ramallah, where fossil-bearing beds occur close to the contact with the Amminadav Formation. Owing to the close stratigraphic relationship between the two units, it remains uncertain whether some of the vertebrate fossils should be assigned to the Bet-Meir Formation or to the overlying formation.[4]
Description
The formation represents a warm, tropical carbonate platform interior, positioned between fully open marine shelf environments and more continental marginal settings, being composed mainly of dolostone that accumulated in tidal-flat and restricted lagoonal settings.[2] The area was under a greenhouse-climate shallow sea.[3] The absence of relatively complete or articulated terrestrial plants suggests that the locality was either far from the nearest landfall or very arid.[5] A good modern analogue is the Laguna Bacalar in Yucatán, as both settings share being a restricted circulation setting with abundant mud sitting on a carbonate platform.[6]
In many areas, these dolostones laterally replace the chalks and limestones assigned to the En Yorqeam Formation, reflecting local environmental differences across the platform.[7] The succession includes fine-grained dolomitic mudstones and siltstones, thin marly layers, laminated algal deposits, and occasional intraformational conglomerates. Features such as iron staining, erosion surfaces, and karstic cavities indicate periodic exposure of the sea floor during temporary drops in sea level. Much of the dolomitization is interpreted as secondary, linked to marine fluids circulating through the sediments during subsequent transgressive phases.[2]
Stratigraphically, the Bet-Meir Formation rests on the Kesalon Formation, whose uppermost beds frequently show signs of erosion and hardground development. It is overlain by the slightly younger Amminadav Formation, characterized by more open-marine carbonate sedimentation and Rudist-bearing limestones. Because the transition between these two formations can be gradual and locally intertonguing, distinguishing their fossil content is sometimes problematic.[1][2][4]
Paleobiota
The majority of species here cannot be confidently assigned the Bet-Meir Formation, and some may instead belong to the younger Amminadav Formation.[4][8]
Invertebrates
Unnamed material of Decapodans, Echinoids, Starfish, Cephalopods and Bivalvia are seen along the outcrops.[9]
| Genus | Species | Presence | Notes | Images |
|---|---|---|---|---|
| Graysonites[9] | G. wacoense | Ein Yabrud quarries | Acanthoceratidae ammonite | |
| Stoliczkaiella[9] | S. amanai | Ein Yabrud quarries | Acanthoceratidae ammonite |
Chondrichthyes
Bony Fish
| Genus | Species | Presence | Notes | Images |
|---|---|---|---|---|
| Aipichthyoides[11] | A. galeatus
A. formosus |
Ein Yabrud quarries | An aipichthyoidid lamprimorph | |
| Dercetoides[12] | D. venator | Ein Yabrud quarries | A dercetid aulopiform | |
| Enchodus[13] | E. brevis | Ein Yabrud quarries | An enchodontid aulopiform | |
| Hastichthys[12] | H. gracilis | Ein Yabrud quarries | A dercetid aulopiform | |
| Judeichthys[14] | J. haasi | Ein Yabrud quarries | A gonorynchid | |
| Judeoberyx[11] | J. princeps | Ein Yabrud quarries | A trachichthyoid trachichthyform | |
| Pachyamia[15] | P. latimaxillaris | Ein Yabrud quarries | An amiid | |
| Pharmacichthys[11] | P. judensis | Ein Yabrud quarries | A pharmacichthyid lamprimorph |  |
| Ramallichthys[16] | R. orientalis | Ein Yabrud quarries | A gonorynchid | |
| Rhombichthys[17] | R. intoccabilis | Ein Yabrud quarries | A paraclupeid clupeomorph |  |
| Saurorhamphus[18] | S. judeaensis | Ein Yabrud quarries | A eurypholid aulopiform | |
| Scalacurvichthys[19] | S. naishi | Ein Yabrud quarries | A pycnodontid |  |
| Serrilepis[20] | S. longidens | Ein Yabrud quarries | A halecid aulopiform | |
| Yabrudichthys[20] | Y. striatus | Ein Yabrud quarries | An enchodontoid aulopiform |
Turtles
| Genus | Species | Presence | Notes | Images |
|---|---|---|---|---|
| Algorachelus[21] | A. parva | Ein Yabrud quarries | A bothremyid side-necked turtle | |
| Pelomedusidae[9] | indet. | Ein Yabrud quarries | An indeterminate pelomedusid side-necked turtle |
Squamates
| Genus | Species | Presence | Notes | Images |
|---|---|---|---|---|
| Haasiasaurus[9] | H. gittelmani | Ein Yabrud quarries | An early mosasaur | |
| Haasiophis[22] | H. terrasanctus | Ein Yabrud quarries | A simoliophiid snake, notable for its hindlimbs | |
| Mesoleptos[23] | M. zendrinii[24] | Ein Yabrud quarries | A basal mosasauroid |  |
| Pachyrhachis[5][10] | P. problematicus | Ein Yabrud quarries | A simoliophiid snake, notable for its hindlimbs |
Pterosaurs
| Genus | Species | Presence | Notes | Images |
|---|---|---|---|---|
| Pterodactyloidea[25] | indet. | Ein Yabrud quarries | An indeterminate pterosaur |
Flora
The dominant component of the flora are encrusting green algae, while terrestrial flora is composed almost exclusively by leaves and stalks or stems of a mangrove gymnosperm (very likely Weichselia based on regional abundance).[26][27]
