In view of the recent recognition of widespread Late Paleozoic remagnetization of Devonian formations across North America, we undertook a reinvestigation of the Upper Devonian Perry Formation of coastal Maine and adjacent New Brunswick. Thermal demagnetization of samples from the redbeds yielded a characteristic direction (D = 166 ° l = 4 ° ) that fails a fold test. Comparison of the correspon...

Article history: Virunga volcanics in the we Received 20 May 2008 Received in revised form 7 November 2008 Accepted 17 November 2008

Alkali-feldspar occurs in the Crowsnest Volcanics as phenocrysts and as free euhedra in the pyroclastics and their re-worked derivatives. Composition varies from 6O/p to 95/6 Or-molecule and 2V f.rom 50'[-f (010)] to 35'[ll(010)l' Individual crystals show a range of 2Zvalues, but only rarely contain more than one K-rich phase. Optics indicate that most of the K-feldspar is intermediate between ...

The Nam Pat Group of the Nam Pat Basin, Uttaradit Province, Thailand is situated in the Nan Suture Zone. Two contrasting tectonic framework models of the Nan Suture have previously been proposed: as a main Paleo-Tethyan suture and as a remnant of a closed back-arc basin. The goal of this study is to analyze the tectonic framework of the Nan Suture and reevaluate the existing tectonic models. Th...

-THE Sierra Leone Rise, located in the east equatorial Atlantic. forms a discontinuous chain of seamounts as shallow as 2 km extending with a general NE-SW trend from near the Sierra Leone Coast of Africa, to the St Paul fracture zone near the Mid-Atlantic Ridge (Fig. 1). The origin of this feature has remained a topic of discussion. Sheridan et al.' have hypothesised that the Sierra Leone Rise...