Metamorphic hydrology at 13 km depth and 400/sup 0/-550/sup 0/C

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6643136

Ferry, J M

The pattern of metamorphic fluid flow through six large outcrops of regionally metamorphosed impure carbonate rock from a single stratigraphic unit in south-central Maine was determined by quantitative measurement of the progress of the prograde devolatilization reactions. With reference to adjacent pelitic schists, the outcrops are located in the chlorite, biotite, garnet, staurolite-andalusite, and sillimanite zones. Two components of flow were detected: a pervasive component and a channelized component. In the chlorite, biotite, and garnet zones fluid flow was highly channelized along bedding with enhanced flow occurring within the more impure carbonate layers that acted as metamorphic aquifers. A smaller amount of pervasive background flow also occurred within the intervening more impure carbonate layers that acted as metamorphic aquifers. A smaller amount of pervasive background flow also occurred within the intervening more pure carbonate layers that acted as metamorphic aquitards. Fluid-rock ratios differ between aquifers and aquitards by a factor greater than 50 over distances of 1 mm or less at grades lower than the staurolite-andalusite zone. Two generalization can be made about the affect of metamorphic grade on patterns of fluid flow: with increasing grade (1) flow becomes less channelized and more pervasive and (b) the average time-integrated fluid flux for a whole outcrop increases. Patterns of metamorphic fluid flow may be rationalized in terms of a model for reaction-enhanced permeability.

• Research Organization: Johns Hopkins Univ., Baltimore, MD (USA)
• OSTI ID: 6643136
• Report Number(s): CONF-8510489-
• Conference Information: Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
580400* -- Geochemistry-- (-1989)
BIOTITE
CARBONATE ROCKS
CHEMICAL REACTION KINETICS
CHEMISTRY
CHLORITE MINERALS
FEDERAL REGION I
FLUID FLOW
FLUIDS
GARNETS
GEOCHEMISTRY
GEOTHERMAL FLUIDS
HYDROLOGY
KINETICS
MAINE
METAMORPHIC ROCKS
METAMORPHISM
MICA
MINERALOGY
MINERALS
NORTH AMERICA
OXYGEN COMPOUNDS
REACTION KINETICS
ROCK-FLUID INTERACTIONS
ROCKS
SCHISTS
SEDIMENTARY ROCKS
SILICATE MINERALS
SILICATES
SILICON COMPOUNDS
USA