Results 141 to 150 of about 31,687 (305)

Fossilized gill soft tissues in Mesozoic freshwater unionoid bivalves: reinvestigation and new evidence of the evolution of adaptation to the freshwater environment

open access: yesActa Palaeontologica Polonica
Large freshwater unionoid bivalves today are a globally distributed and diverse group, with a history dating back to the Triassic. Their evolutionary success largely depends on their reproductive behavior, today, they all take maternal care via brooding ...
Aleksandra Skawina   +1 more
doaj   +1 more source

The Unexpected Discovery of Paleocene? Coals in Outcrops Thought to Be Cambrian, Al Huqf, Oman

open access: yesJournal of Petroleum Geology, EarlyView.
ABSTRACT Two brown organic deposits were encountered whilst investigating kaolinitic claystones thought to occur at the base of a Cambrian formation at outcrop. The age of these organic deposits is probably Paleocene from palynology. Organic petrography shows that they are subbituminous coals with some oil source potential.
Mohammed H. Al Kindi   +4 more
wiley   +1 more source

Mesozoic and Cenozoic marine benthic calcareous algae with particular regard to Mesozoic Dasycladaleans [PDF]

open access: yes, 1990
A review of the Mesozoic algae is supplied, an outline of the distribution of algae during the geological time is ...
BARATTOLO, FILIPPO
core  

1D Basin Modelling of Upper Jurassic to Upper Cretaceous Source Rocks in the Southern Pletmos Sub‐Basin, Outeniqua Basin, Offshore South Africa

open access: yesJournal of Petroleum Geology, EarlyView.
ABSTRACT The Pletmos sub‐basin in the Outeniqua Basin, offshore South Africa, is divided by the Superior, Pletmos and Plettenberg faults into northern and southern depocentres. In this study, geological and organic geochemical data together with 1D basin modelling were used to investigate the burial, thermal and maturation histories, and the timing of ...
Fritz Ako Agbor   +4 more
wiley   +1 more source

Spatial and temporal evolution of a coastal erg margin: the Middle Jurassic Page Sandstone, southern Utah, USA

open access: yesSedimentology, EarlyView.
ABSTRACT Aeolian deflationary events are erosive to static stages where sediment supply is insufficient to support bedform migration and preservation in the rock record. In the vicinity of shallow‐marine environments, inland rises of relative water table and associated generation of deflationary super surfaces may be driven by the onset of ...
Victor J. P. Hême de Lacotte   +4 more
wiley   +1 more source

Recognition of fossil keratose sponges in carbonates using petrographic and machine‐learning classification

open access: yesSedimentology, EarlyView.
ABSTRACT Filamentous, anastomosing spar‐filled networks in Phanerozoic carbonates have been interpreted as the mineralised remains of keratose (non‐spiculate) sponges, yet their recognition remains contested because fabrics of broadly similar appearance may arise from microbial, diagenetic or physical processes. This study combines direct fossil–modern
Jeong‐Hyun Lee   +2 more
wiley   +1 more source

A Triassic chronostratigraphic and palaeogeographic framework for the Utsira High area, northern North Sea: Reconstructing a basin‐scale drainage divide

open access: yesSedimentology, EarlyView.
ABSTRACT The Triassic succession of the northern North Sea comprises a series of interbedded sandstones, mudstones and conglomerates deposited under a fluctuating arid to semi‐humid climate regime, which are often difficult to correlate regionally due to differing lithostratigraphic schemes and poor age control. Despite existing regional studies on the
Riccardo Sordi   +3 more
wiley   +1 more source

Mesozoic Stratigraphy at Durango, Colorado [PDF]

open access: yes, 2005
A nearly 3-km-thick section of Mesozoic sedimentary rocks is exposed at Durango, Colorado. This section consists of Upper Triassic, Middle-Upper Jurassic and Cretaceous strata that well record the geological history of southwestern Colorado during much ...
NC DOCKS at Appalachian State University   +1 more
core  

Porosity Preservation in Deeply Buried (8500 m) Jurassic Calcareous Mudstones of the Vienna Basin (Austria)

open access: yesTerra Nova, EarlyView.
ABSTRACT Significant porosity of more than 5% was found at depths of more than 8500 m in poorly sorted, calcareous mudstones of the Malmian Mikulov Formation. These overpressured rocks are the main hydrocarbon source rock in the Vienna Basin. Core samples from present‐day depths of 8150 m to 8550 m were analysed using X‐ray diffraction and scanning ...
Susanne Gier   +3 more
wiley   +1 more source

On the Origin of the Tingidae (Insecta, Heteroptera)

open access: yesZoologica Scripta, EarlyView.
ABSTRACT The hypothesis of a Gondwanian origin of the family Tingidae (Insecta, Heteroptera) has been promoted and seems to be generally accepted by specialists. However, the area of emergence and diversification of the clade, South American or Australian, is still debated and cannot be solved without integrating Vianaidinae, a subfamily considered as ...
Gilardet Rémy   +3 more
wiley   +1 more source

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