scholarly journals Shallow-marine serpentinization-derived fluid seepage in the Upper Cretaceous Qahlah Formation, United Arab Emirates

2021 ◽  
pp. 1-11
Author(s):  
Benjamin Eickmann ◽  
Crispin T. S. Little ◽  
Jörn Peckmann ◽  
Paul D. Taylor ◽  
Adrian J. Boyce ◽  
...  

Abstract Serpentinization of ultramafic rocks in the sea and on land leads to the generation of alkaline fluids rich in molecular hydrogen (H2) and methane (CH4) that favour the formation of carbonate mineralization, such as veins in the sub-seafloor, seafloor carbonate chimneys and terrestrial hyperalkaline spring deposits. Examples of this type of seawater–rock interaction and the formation of serpentinization-derived carbonates in a shallow-marine environment are scarce, and almost entirely lacking in the geological record. Here we present evidence for serpentinization-induced fluid seepage in shallow-marine sedimentary rocks from the Upper Cretaceous (upper Campanian to lower Maastrichtian) Qahlah Formation at Jebel Huwayyah, United Arab Emirates. The research object is a metre-scale structure (the Jebel Huwayyah Mound) formed of calcite-cemented sand grains, which formed a positive seafloor feature. The Jebel Huwayyah Mound contains numerous vertically orientated fluid conduits containing two main phases of calcite cement. We use C and O stable isotopes and elemental composition to reconstruct the fluids from which these cements precipitated and infer that the fluids consisted of variable mixtures of seawater and fluids derived from serpentinization of the underlying Semail Ophiolite. Based on their negative δ13C values, hardgrounds in the same section as the Jebel Huwayyah Mound may also have had a similar origin. The Jebel Huwayyah Mound shows that serpentinization of the Semail Ophiolite by seawater occurred very soon after obduction and marine transgression, a process that continued through to the Miocene, and, with interaction of meteoric water, up to the present day.

2003 ◽  
Vol 77 (1) ◽  
pp. 50-63 ◽  
Author(s):  
Richard L. Squires ◽  
Louella R. Saul

Three new genera and six new species of shallow-marine gastropods are named from Upper Cretaceous strata found mainly in California. The trochidsCidarina cretaceanew species andCidarina betanew species, the ficidBulbificopsis garzanew genus and new species, and the cancellariidMataxa aridanew species are from the Maastrichtian part of the Moreno Formation of north-central California. This is the earliest record ofCidarina, whose previous chronologic range was middle Eocene to Recent.Bulbificopsisis the first record of a Cretaceous ficid from the Pacific slope of North America, andMataxawas previously known only from Upper Cretaceous strata in the southeastern United States and northeastern Brazil. The buccinidEripachya jalamanew species and the fasciolariidCalkota daileyinew genus and new species are from the lower upper Campanian Jalama Formation in southern California.Calkotais also recognized herein as occurring in upper Maastrichtian strata of North Dakota and South Dakota. The new melongenid genus,Pentzia, established forFulgur hilgardiWhite, 1889, is from Campanian strata throughout California; middle Campanian strata on Sucia Island, Washington; and upper Campanian to lower Maastrichtian strata in northern Baja California, Mexico.


Palaeontology ◽  
2007 ◽  
Vol 50 (5) ◽  
pp. 1051-1071 ◽  
Author(s):  
JÜRGEN KRIWET ◽  
RODRIGO SOLER-GIJÓN ◽  
NIEVES LÓPEZ-MARTÍNEZ

2001 ◽  
Vol 172 (2) ◽  
pp. 237-244 ◽  
Author(s):  
Marcelo de la Fuente ◽  
France de Lapparent de Broin ◽  
Teresa Manera de Bianco

Abstract A new pleurodiran (side necked) turtle is described on material from the Upper Cretaceous of Patagonia, from sediments outcropping at Cerro Blanco, Yaminue Creek, Rio Negro, Argentina. The sediments are compared to those from the Pellegrini lake area referred to the middle Member of the Allen Formation, Upper Campanian-Lower Maastrichtian. Yaminuechelys gasparinii n.g., n.sp., is a pleurodiran turtle on the pelvis sutured to the shell and a chelid on the formula of cervical vertebrae and the lateral cheek emargination, deeply extended towards (as here) or up to the posterior emargination. It is the oldest record of a nearly complete skeleton of a chelid, long necked (elongated cervical vertebrae, lowered skull), and the first sufficiently known of the Chelodina-Hydromedusa group (elongated skull, lowered neural arch and centrum of the cervicals, low zygapophyses processes, strong polygoned decoration) and of the Hydromedusa sub-group (widened inner nares by reduced palatine ossification). The carapace is 41,8 cm long. It is more primitive than Hydromedusa (Eocene-Extant, South America) and retains primitive characters either still present or no more present in the other chelids of the Pseudemydura, Emydura and Phrynops groups (short necked) and Chelus group (long necked), representing the anterior clades of phyletic diversification [Gaffney, 1977], or evolutive grades, of the family. Such are plesiomorphic, relative to Hydromedusa, the less pronounced lateral skull emargination, wider and longer hyoid elements, wider nucal and cervical, this not drawn back, presence of lateral mesoplastra, not shortened bridge, straight borders of the not shortened and not widened posterior plastral lobe, amphicoelous sacrals and caudal vertebrae uniting amphicoelous, concavoplaty--(i.e. anteriorly concave, posteriorly flat) and procoelous or weakly procoelous elements. As Hydromedusa, Yaminuechelys n. g. retains primitive characters such as the long series of neurals, the very lateral attachment of the axillar and inguinal processes and the attachment of the pelvis, below pleural 8 (and 7 in the extant form) and a small part of the suprapygal, and the ischitatic sutures prolonged on the xiphiplastral points. It is distinguished by the apomorphic presence of a wide and week anterior carapacial notch. Yaminuechelys n.g., or aff. Yaminuechelys spp. are known in Patagonia by fragmentary remains in a dozen of Upper Cretaceous and two Palaeocene localities. Before them, chelids are known in the world only by undefined smaller forms from Lower Albian and Upper Albian-Cenomanian Patagonian localities. In Australia, they are known from Palaeocene-Lower Eocene (no Cretaceous data before) with already extant Australian diversified forms. Yaminuechelys n.g. demonstrates how long the diversification in chelids is realized in South Gondwana before the full break of the continents.


2020 ◽  
Vol 441 (1) ◽  
pp. 1
Author(s):  
Neil H. Landman ◽  
W. James Kennedy ◽  
Joyce Grier ◽  
Neal L. Larson ◽  
James W. Grier ◽  
...  

2012 ◽  
Vol 25 (1) ◽  
pp. 71-82 ◽  
Author(s):  
José P. O'Gorman ◽  
Zulma Gasparini ◽  
Leonardo Salgado

AbstractA partial, postcranial skeleton of a juvenile individual referred to Aristonectes cf. parvidens from the upper Maastrichtian López de Bertodano Formation, Isla Marambio (Seymour Island), Antarctica, is described. Additionally, two juvenile specimens, also referred to A. cf. parvidens from the Allen Formation (upper Campanian–lower Maastrichtian) and Jagüel Formation (upper Maastrichtian) (Río Negro province, Argentina), are redescribed. The analysis of the systematic value of the cervical centrum proportions of juvenile specimens of Elasmosauridae suggests that these elements can be used to differentiate juvenile specimens of A. cf. parvidens from juveniles of other Elasmosauridae. On this basis, the specimens described are referred to A. cf. parvidens. Based on the proportion of the cervical centra, the first South American plesiosaur described by Gay in 1848 is here referred to A. cf. parvidens. The coracoid of Aristonectes is described for the first time showing a cordiform fenestra, a feature only recorded in the Elasmosauridae among the Plesiosauria, therefore, these new data support the inclusion of Aristonectes within the Elasmosauridae. With the new material described in this paper, Aristonectes is one of the most frecuently recorded genera of Late Cretaceous plesiosaurs in the Southern Hemisphere.


2019 ◽  
Vol 21 ◽  
pp. 217-293 ◽  
Author(s):  
Fernando Novas ◽  
Federico Agnolin ◽  
Sebastián Rozadilla ◽  
Alexis Aranciaga-Rolando ◽  
Federico Brissón-Eli ◽  
...  

GeoArabia ◽  
1998 ◽  
Vol 3 (3) ◽  
pp. 387-398
Author(s):  
M. Atef Noweir ◽  
Abdulrahman S. Alsharhan ◽  
Mohamed A. Boukhary

ABSTRACT The Faiyah Range belongs to a group of regional ridges that formed by post-obduction folding of the Upper Cretaceous-Tertiary sedimentary rocks exposed along the western margin of the Northern Oman Mountains. The Faiyah Anticline, generally trends north-northeast to south-southwest with thrust faults striking parallel to the fold axis. The anticlinal hinge was later displaced by a dextral strike-slip fault, named here as the Faiyah Fault, into two segments. The northeastern segment includes Jebels Rumaylah, Faiyah and Mulayhah, and the southwestern segment includes Jebels Buhays and Aqabah. The anticline is interpreted to result from northeast-southwest compression during the Tertiary. In the Faiyah Range the neoautochthonous sedimentary rocks are the Maastrichtian Qahlah and Simsima formations, and the Eocene Dammam Formation. Stratigraphic evidence shows that the lower part of the Qahlah was deposited in a non-marine environment while the upper part was deposited during a marine transgression. The Simsima was deposited in a shallow-marine environment. These units unconformably overlap the allochthonous Semail Ophiolite. The microfaunal content of the so-called Muthaymimah Formation (?Tertiary), of earlier authors, indicates that it is of Maastrichtian age in the Faiyah Range. This sequence is also conformable to the Simsima and therefore it is considered to be the upper member of the Simsima in this area.


Fossil Record ◽  
2003 ◽  
Vol 6 (1) ◽  
pp. 161-168
Author(s):  
A. López-Arbarello ◽  
G. Arratia ◽  
M. A. Tunik

Some isolated acanthomorph remains and a new taxon of perciform fishes, <i>Saldenioichthys remotus</i> gen. et sp. nov., from the Maastrichtian Saldeño Formation of Mendoza province, Argentina, are described and their systematic affinities are discussed. The new taxon is represented by a single incomplete, but well preserved postcranial skeleton. With the exception of a fully developed neural spine on the second preural centrum, it agrees with the generalized skeletal features of basal percoids, in particular the generalized perciform caudal skeleton. The only other Mesozoic perciform skeletal remains known so far are <i>Nardoichthys</i>, from the upper Campanian-lower Maastrichtian of Nardo (Italy) and <i>Eoserranus</i> from the Upper Cretaceous Lameta Formation (India). Therefore, the new perciform taxon from the Saldeño Formation represents one of the oldest members of this group, and due to its peculiar combination of primitive and derived characters, it raises several questions regarding character evolution on this lineage. <br><br> Es werden einige isolierte Reste acanthomorpher Fische sowie ein neues Taxon der Perciformes, <i>Saldenioichthys</i> remotus gen. et sp. nov., aus dem Maastricht der Saldeño Formation in der Provinz Mendoza, Argentinien, werden beschrieben und ihre systematische Stellung wird diskutiert. Das neue Taxon ist durch ein einziges, unvollständiges, aber gut erhaltenes postkraniales Skelett repräsentiert. Mit Ausnahme eines vollstandig ausgebildeten Dornfortsatzes auf dem ersten präuralen Zentrum stimmt es mit der generalisierten Skelettmorphologie basaler Percoiden überein, insbesondere mit dem generalisierten perciformen Caudal-Skelett. Die einzigen anderen Skelettreste von Perciformen aus dem Mesozoikum sind <i>Nardoichthys</i> aus dem Ober-Campan/Unter-Maastricht von Nardo, Italien, und <i>Eoserranus</i> aus der Oberkreide der Lameta Formation, Indien, und die Gruppe ist ansonsten praktisch nur aus känozoischen Sedimenten bekannt. Somit stellt das neue Taxon aus der Saldeño Formation einen der ältesten Nachweise dieser Gruppe dar, und wirft aufgrund seiner ungewöhnlichen Kombination primitiver und fortschrittlicher Merkmale einige Fragen zur Merkmalsevolution in dieser Linie auf. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20030060109" target="_blank">10.1002/mmng.20030060109</a>


2013 ◽  
Vol 63 (4) ◽  
pp. 611-623 ◽  
Author(s):  
Agata Jurkowska ◽  
Alfred Uchman

ABSTRACT Jurkowska, A. and Uchman, A. 2013. The trace fossil Lepidenteron lewesiensis (Mantell, 1822) from the Upper Cretaceous of southern Poland. Acta Geologica Polonica, 63(4), 611-623. Warszawa. Lepidenteron lewesiensis (Mantell, 1822) is an unbranched trace fossil lined with small fish scales and bones, without a constructed wall. It is characteristic of the Upper Cretaceous epicontinental, mostly marly sediments in Europe. In the Miechow Segment of the Szczecin-Miechow Synclinorium in southern Poland, it occurs in the Upper Campanian-Lower Maastrichtian deeper shelf sediments, which were deposited below wave base and are characterized by total bioturbation and a trace fossil assemblage comprising Planolites, Palaeophycus, Thalassinoides , Trichichnus, Phycosiphon, Zoophycos and Helicodromites that is typical of the transition from the distal Cruziana to the Zoophycos ichnofacies. L. lewesiensis was produced by a burrowing predator or scavenger of fishes. The tracemaker candidates could be eunicid polychaetes or anguillid fishes.


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