Fluid flow during metamorphism at the Beaver Brook fossil locality, New Hampshire.

Abstract

The magnitude of quenched decarbonation reactions, as measured by petrographic modal analysis, and the 18O depletion of the fossil brachiopod bed serve as a basis for estimating the minimum, time-integrated flux of fluid through the Early Devonian rocks of the locality during metamorphism associated with the Acadian orogeny. A table showing mineral assemblages and chemical and isotopic data is included, and data on mineral solid solutions, thermodynamic data, and isotopic fractionation during dehydration and decarbonation are appended.-M.S.Geophysical Lab, Carnegie Inst., Washington, DC 20008, USA.