1,721,047 research outputs found
Ar/Ar geochronology of Mesozoic continental basaltic magmatism of the central, equatorial and southern Atlantic ocean
No full textThe Central Atlantic flood basalt province and possible relationship with Triassic-Jurassic magmatism in the Andes.
No full textGeocronology and palaeomagnetism of Triassic-Jurassic tholeiitic magmatism in Brazil and implications for the Central Atlantic Magmatic Province.
No full textThe Central Atlantic Province, 40Ar/39Ar geochronology and paleomagnetism of Earth’s largest known continental flood basalts.
No full textAr/Ar geochronology of the Central Atlantic Magmatic Province, and of Jurassic-Cretaceous magmatism in Brazil.
No full textThe Central Atlantic Magmatic Province at the Triassic-Jurassic boundary: paleomagnetic and 40Ar/39Ar evidence from Morocco for brief, episodic volcanism
No full textThe Central Atlantic Magmatic Province (CAMP), one of the largest known flood basalt provinces formed in the
Phanerozoic, is associated with the pre-rift stage of the Atlantic Ocean at the Triassic–Jurassic boundary ca. 200 Ma.
Paleomagnetic sampling targeted packages of CAMP lava flows in Morocco’s High Atlas divided into four basic units (the
lower, intermediate, upper, and recurrent units) from sections identified on the basis of field observations and geochemistry.
Oriented cores were demagnetized using both alternating field (AF) and thermal techniques. Paleomagnetic results reveal
wholly normal polarity interrupted by at least one brief reversed chron located in the intermediate unit, and reveal distinct pulses
of volcanic activity identified by discrete changes in declination and inclination. These variations in magnetic direction are
interpreted as a record of secular variation, and they may provide an additional correlative tool for identification of spatially
separated CAMP lava flows within Morocco. 40Ar/39Ar analyses of Moroccan CAMP lavas yield plateau ages indistinguishable
within 2r error limits, sharing a weighted mean age of 199.9F0.5 Ma (2r), reinforcing the short-lived nature of these eruptions
despite the presence of sedimentary horizons between them. Correlation of our sections with the E23n, E23r, E24 sequence
reported in the Newark basin terrestrial section and St. Audrie’s Bay marine section is suggested. Brief volcanism in sudden
pulses is a potential mechanism for volcanic-induced climatic changes and biotic disruption at the Triassic–Jurassic boundary.
Combination of our directional group (DG) poles yields an African paleomagnetic pole at 200 Ma of k(8N)=73.08,
/(8E)=241.38 (Dp=5.08, Dm=18.58)
The Central Atlantic Magmatic Province: Extensive 200 Million year old Continental Flood Basalt.
No full textExtensive 200 million years old continental flood basalts from the Central Atlantic Magmatic Province.
No full textThe Central Atlantic Province, 40Ar/39Ar geochronology and Paleomagnetism of Earth’s largest known continental flood basalts.
No full textThe earliest Jurassic Circum-Atlantic large igneous province; new evidence for a brief, extremely widespread event
No full text- …
