Results 61 to 70 of about 38,084 (244)

Embryonic development of the Mediterranean starfish Hacelia attenuata

open access: yesDevelopmental Dynamics, EarlyView.
Abstract Background Starfish play essential ecological roles as predators and ecosystem regulators; however, detailed developmental descriptions exist for only a handful of species, none of which are from the Mediterranean Sea. Results In this study, we provide the first full account of the development of the Mediterranean starfish Hacelia attenuata ...
Silvia Caballero‐Mancebo   +3 more
wiley   +1 more source

Imbrication and Erosional Tectonics Recorded by Garnets in the Sikkim Himalayas

open access: yesGeosciences, 2022
The Sikkim region of the Himalayas (NE India) may form an important microplate between Nepal and Bhutan. Here we report high-resolution pressure-temperature (P-T) paths taken from garnet-bearing rocks across the northern and eastern portion of the region’
Elizabeth J. Catlos   +2 more
doaj   +1 more source

A Reassessment of Petrochemistry of ~1.2 Ga Tonalitic Rocks of the Northern Tugela Terrane, Natal Metamorphic Belt, South Africa: Further Constraints on the Evolution of This Belt

open access: yesGeological Journal, EarlyView.
Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta   +2 more
wiley   +1 more source

Cooling history of the eastern Svecokarelides: whole-rock and mica Rb-Sr and hornblende K-Ar ages in the areas of Pihtipudas-Iisalmi and Joroinen-Sulkava, Finland [PDF]

open access: yesBulletin of the Geological Society of Finland, 1990
Rb-Sr age determination on mica and whole-rock samples and K-Ar age determination on hornblendes were carried out to get information on the time of metamorphism and early cooling in two Proterozic areas of the Finnish Svecokarelides.
U. Haudenschild
doaj   +1 more source

Spatio-Temporal Evolution of Intermediate-Depth Seismicity Beneath the Himalayas: Implications for Metamorphism and Tectonics

open access: yesFrontiers in Earth Science, 2021
Intermediate-depth earthquakes (>40 km) have been observed beneath the central Himalayas over decades, with little known about their nature and characteristics.
Konstantinos Michailos   +3 more
doaj   +1 more source

Thermal structure of the crust during granulite metamorphism: petrological speculations and geodynamic implications [PDF]

open access: yes, 1998
P(論文)It is shown on a basis of generalization of lateral and vertical distribution of P-T parameters in granulite-gneiss belts of various ages that the thermal gradient within the lower crust during granulite metamorphism is rather low, ca. 5-10℃/km. Two
Mints,Michael V., Konilov,Alexander N.
core  

Apatite in Carbonatite Preserving Primary Magmatic, Post‐Magmatic Overgrowth, and Post India‐Asia Collision‐Related Hydrothermal Alteration: Evidenced From U–Pb Isotope and Trace Element Geochemistry

open access: yesGeological Journal, EarlyView.
U–Pb isotope and trace element geochemistry of apatite from carbonatites of Peshawar Plain Alkaline Igneous Province, western Himalaya shows Permo‐Carboniferous magmatism, an additional magmatic pulse during Cretaceous, and post‐magmatic hydrothermal/metasomatism during Oligocene. ABSTRACT U–Pb isotope and trace element geochemistry of apatite combined
Mehboob ur Rashid   +9 more
wiley   +1 more source

Metamorphism of Fe - Ni ores from Rzanovo - Studena Voda (Yugoslavia) and the Zone Almopias (Greece) [PDF]

open access: yes, 1985
the work about metamorphism of the Fe-Ni ores from Rzanovo ­ Studena Voda, deals with the problem of the degree of metamorphism, on the bases of the consolidatet mineral paragenesis in the Fe-Ni ores.
Boev, Blazo, Stojanov, Risto
core   +2 more sources

Metamorphism and Metamorphic Rocks

open access: yes, 2013
In the previous chapters, we learned about igneous and sedimentary rocks. This chapter presents some general concepts concerned with the process of metamorphism and the formation of metamorphic rocks. How pressure, temperature, and fluids control metamorphic processes and resulting metamorphic changes are discussed.
openaire   +1 more source

Heterogeneous Exhumation Mechanisms in Neoproterozoic Collisional Metamorphism: P–T Constraints From Pelotas and Punta del Este Terranes, Southern Brazil and Uruguay

open access: yesGeological Journal, EarlyView.
Petrography, thermobarometry, and pseudosection modelling reveal peak metamorphic conditions of 3–7.5 kbar and 520°C–800°C in Tonian‐Cryogenian orthogneisses of the Dom Feliciano Belt. Metamorphic field gradients of 27°C/km–39°C/km and variable exhumation mechanisms support correlation of these units as remnants of a Himalayan‐type Piratini Orogeny ...
Thaiane Niederauer‐Santos   +6 more
wiley   +1 more source

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