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6876444 
Journal Article 
GEOCHEMISTRY OF THE START COMPLEX GREENSCHISTS - RHENOHERCYNIAN MORB 
Floyd, PA; Holdsworth, RE; Steele, SA; , 
1993 
Yes 
Geological Magazine
ISSN: 0016-7568
EISSN: 1469-5081 
CAMBRIDGE UNIV PRESS 
NEW YORK 
345-352 
WOS:A1993LG21400005 
The meta-igneous greenschists of the Start Complex, South Devon, are composed of a mineralogically uniform, but texturally variable, actinolite-epidote-albite assemblage with retrogressed variants containing chlorite, muscovite, sphene, carbonate and oxidized opaque minerals. Geochemically they represent a suite of relatively primitive tholeiites, exhibiting mild differentiation, depleted incompatible element abundances, and variable light rare-earth-element-depletion patterns comparable to modem basalts from normal spreading ridge segments (N-MORB). As the Start greenschists exhibit a number of chemical similarities to the nearby Upper Palaeozoic Lizard ophiolite, and MORB-type clasts within the Rhenohercynian Zone generally, they may also represent local Variscan ocean crust, which floored small oceanic basins that separated the Old Red Sandstone continent from the Armorican microplate to the south. The Start Complex could thus represent a previously unrecognized oceanic component to the Variscan orogenic belt (Rhenohercynian Zone) of Northwest Europe.