Late Jurassic-Early Cretaceous oceanic crust and early cretaceous volcanic sequences of the Nauru basin, western Pacific

1993 ◽  
pp. 103-119 ◽  
Author(s):  
Thomas H. Shipley ◽  
Lewis J. Abrams ◽  
Yves Lancelot ◽  
Roger L. Larson
Keyword(s):  
Oceanic Crust ◽  
Early Cretaceous ◽  
Late Jurassic ◽  
Western Pacific

The newest structures of the Heraclion peninsula (South-Western Crimea)

2019 ◽  
pp. 8-16
Author(s):  
M. Yu. Promyslova ◽  
G. V. Bryantseva ◽  
L. I. Demina ◽  
N. I. Kosevich
Keyword(s):  
Oceanic Crust ◽  
Coastal Zone ◽  
Early Cretaceous ◽  
Late Jurassic ◽  
Fracture Zones ◽  
The South ◽  
South Eastern ◽  
Back Arc ◽  
Geomorphological Analysis

The article presents the results of the structural-geomorphological analysis of the Heraklion peninsula of the South-Western Crimea. The Western, Central and South-Eastern segments are distinguished, differing in density and direction of fracture zones, faults, the nature of the ravine-gulch net, and the structure of the coastal zone. It is shown that neotectonic movements in the upper structural floor are most intensively manifested over the Late Jurassic-Early Cretaceous collisional suture formed when the back-arc basin with the oceanic crust was closed.

scholarly journals Metamorphic Conditions of Neotethyan Meliatic Accretionary Wedge Estimated by Thermodynamic Modelling and Geothermobarometry (Inner Western Carpathians)

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1094
Author(s):  
Ondrej Nemec ◽  
Marián Putiš ◽  
Peter Bačík ◽  
Peter Ružička ◽  
Zoltán Németh
Keyword(s):  
High Pressure ◽  
Oceanic Crust ◽  
Early Cretaceous ◽  
Continental Margin ◽  
Late Jurassic ◽  
Hanging Wall ◽  
Western Carpathians ◽  
Accretionary Wedge ◽  
Metamorphic Evolution ◽  
Lower Temperature

Metamorphic evolution of an accretionary wedge can be constrained by a reconstructed P–T conditions of the oceanic and continental margin fragments. This paper deals with the metamorphic overprinting of the Inner Western Carpathians (IWC) Meliatic Triassic–Jurassic paleotectonic units after the closure of the Neotethyan Meliata Basin. Medium to high-pressure and lower temperature conditions were estimated by Perple_X pseudosection modelling, combined with garnet–phengite, calcite–dolomite and chlorite thermometers and chlorite–phengite and phengite barometers. The Late Jurassic subductional burial to a maximum 50 km depth was estimated from the Bôrka Unit continental margin fragments at 520 °C and 1.55 GPa. This is compatible with the metamorphic peak garnet–glaucophane–phengite assemblage of blueschist facies in metabasites. The Jaklovce Unit oceanic fragments were subducted to maximum 35–40 km at 390–420 °C and 1.1–1.3 GPa. Metabasalts and metadolerites contain winchite, riebeckite, actinolite, chlorite, albite, epidote and phengite. A glaucophane-bearing metabasalt recorded an intra-oceanic subduction in blueschist-facies conditions. Rare amphibolite-facies metabasalts of this unit indicate the base of an inferred oceanic crust sliver obducted onto the continental margin wedge. The Meliata Unit oceanic/continental margin flysch calciclastic and siliciclastic metasediments suggest the burial to approximately 15–20 km at 250–350 °C and 0.4–0.6 GPa. This is indicated by a newly formed albite, K-feldspar, illite–phengite and chlorite associated with quartz and/or calcite and dolomite in these rocks. Magnesio-hastingsite to magnesio-hornblende bearing metagabbro with newly formed metamorphic magnesio-riebeckite and actinolite is an inferred detached Meliatic block tectonically emplaced in a Permian salinar mélange in the Silica Nappe hanging wall. Reconstructed P–T paths indicate variable metamorphic conditions from the medium-pressure to high-pressure subduction of the Bôrka and Jaklovce units to the Meliata Unit shallow burial in an accretionary wedge during Late Jurassic to Early Cretaceous Meliaticum evolution. Mélange blocks of Meliaticum incorporate different juxtaposed Meliatic paleotectonic units exposed in nappe outliers overlying the IWC Gemeric and Veporic superunits.

AGE MODEL FOR LATE JURASSIC THROUGH EARLY CRETACEOUS USED IN THE GEOLOGIC TIMESCALE 2012/2016 REFERENCE SCALES

2018 ◽  
Author(s):  
James G. Ogg ◽  
◽  
Chunju Huang ◽  
Chunju Huang ◽  
Linda A. Hinnov ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Late Jurassic ◽  
Age Model

Theropod teeth from the basalmost Cretaceous of Anoual (Morocco) and their palaeobiogeographical significance

2009 ◽  
Vol 146 (4) ◽  
pp. 602-616 ◽  
Author(s):  
F. KNOLL ◽  
J. I. RUIZ-OMEÑACA
Keyword(s):  
Early Cretaceous ◽  
Late Jurassic ◽  
Dispersal Events ◽  
Early Occurrence

AbstractThe theropod teeth from the Berriasian (Early Cretaceous) site of Anoual (N Morocco) are described. The assemblage is important in that it comes from one of the very few dinosaur sites of this age globally and the only one for the whole of Gondwana. The theropod teeth from Anoual are morphologically diverse. Most of the material possibly belongs to the clade Dromaeosauridae, which would be an early occurrence for this taxon. The palaeogeographic position of Anoual enables it to provide data on the dispersal events that affected terrestrial faunas during Mesozoic times. A Laurasian influence is evidenced by the presence of Velociraptorinae and, on the whole, the theropod fauna from Anoual provides support for the existence of a trans-Tethyan passage allowing terrestrial faunal interchanges during Late Jurassic and/or earliest Cretaceous times. Additionally, Anoual records the existence of diminutive theropods. However, it cannot yet be determined whether the small size of the specimens is genetic or ontogenetic.

scholarly journals Late Jurassic-Early Cretaceous palynostratigraphy and palaeoclimate in the Andigama Basin, Sri Lanka

2021 ◽  
pp. 100067
Author(s):  
Panchala Weerakoon ◽  
Harinam Joshi ◽  
Neha Aggarwal ◽  
Neerja Jha ◽  
Hetti Arachchige Hemachandra Jayasena ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Early Cretaceous ◽  
Late Jurassic

New multituberculate mammal from the Early Cretaceous of eastern North America

2013 ◽  
Vol 50 (3) ◽  
pp. 315-323 ◽  
Author(s):  
Richard L. Cifelli ◽  
Cynthia L. Gordon ◽  
Thomas R. Lipka
Keyword(s):  
North America ◽  
Iberian Peninsula ◽  
Early Cretaceous ◽  
North American ◽  
Lower Cretaceous ◽  
Late Jurassic ◽  
Relative Length ◽  
Central Position ◽  
Eastern North America ◽  
The North

Multituberculates, though among the most commonly encountered mammalian fossils of the Mesozoic, are poorly known from the North American Early Cretaceous, with only one taxon named to date. Herein we describe Argillomys marylandensis, gen. et sp. nov., from the Early Cretaceous of Maryland, based on an isolated M2. Argillomys represents the second mammal known from the Arundel Clay facies of the Patuxent Formation (Lower Cretaceous: Aptian). Though distinctive in its combination of characters (e.g., enamel ornamentation consisting of ribs and grooves only, cusp formula 2:4, presence of distinct cusp on anterobuccal ridge, enlargement of second cusp on buccal row, central position of ultimate cusp in lingual row, great relative length), the broader affinities of Argillomys cannot be established because of non-representation of the antemolar dentition. Based on lack of apomorphies commonly seen among Cimolodonta (e.g., three or more cusps present in buccal row, fusion of cusps in lingual row, cusps strongly pyramidal and separated by narrow grooves), we provisionally regard Argillomys as a multituberculate of “plagiaulacidan” grade. Intriguingly, it is comparable in certain respects to some unnamed Paulchoffatiidae, a family otherwise known from the Late Jurassic – Early Cretaceous of the Iberian Peninsula.

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