IS THE STOWE-OTTAUQUECHEE BELT OF VERMONT AN EAST-DIRECTED ALLOCHTHON FROM THE TACONIAN HINTERLAND?

St.Julien and Hubert’s (1975)¹ classic paper for the Taconian Orogen of the Quebec Appalachians describe east directed internal domain allochthons of Caldwell/Rosaire rocks following ophiolite emplacement. Pinet et al. (1996)² further demonstrate that these rocks are truncated from the root zone to the west by a steep down to the east normal fault of pre-Acadian age referred to as the St.Joseph’s fault. We argue that the Stowe Ottauquechee Belt (SOB) along the east side of the Green Mountain anticlinorium (GMA) of northern Vermont are southern continuations of these eastward directed Caldwell/Rosaire rocks. Evidence supporting rooting the SOB rocks close to the present axis of the GMA are as follows: 1) Black graphitic and silver green lithologies lithically similar to the SOB are located in the Foot Brook Slice which structurally overlies albitic core rocks within the GMA along the Prospect Rock Fault (PRF; Thompson et al. 1999)³; 2) sense of shear indicators for albite porphyroblasts below the PRF support west over east motion; 3) chemistry of all graphitic rocks across the Taconian hinterland (Sweetsburg, Foot Brook, Ottauquechee and Hazens Notch) support a common protolith within the ancient margin of Laurentia; 4) the Burgess Branch Fault (Kim et al., 1999)⁴ has documented down to the east sense of shear similar to the St. Joseph fault of Quebec and juxtaposes SOB rocks against albitic core rocks of the GMA with apparent structural and metamorphic contrast. The model removes the difficulties in deriving the SOB/Foot Brook slice rocks from the east over already emplaced ophiolitic and aureole rocks of the Belvidere Complex. We envision allochthon emplacement followed an early Taconian foreland directed wedge of garnet grade albitic core rocks (Hazens Notch and Fayston rocks), locally containing blueschist, which moved cover rocks eastward along the PRF with late pre-Acadian down to the east motion along the Burgess Branch fault. ¹. AJS, Vol 275;². CJES vol. 33; ³. NEIGC,1999, p. 51; ⁴ NEIGC, 1999, p. 213.