Hydrothermal alteration of sediments in the high-temperature reaction zone at Central Hill of Escanaba Trough, Gorda Ridge

Abstract

In sediments from Holes ODP 1038A and 1038H, drilled near the hot springs at Central Hill, Escanaba Trough (Gorda Ridge), redistribution of major elements occurs during the water-rock interaction. Contents of Si, Fe, Mg, Ca, Na and K have changed in altered sediments. In this process, an increase/decrease in contents of major elements in altered sediments shows a decrease/increase in their contents in fluids. The irregular distribution of major elements in altered sediments resembles a layer pie, which reflects the existence of lateral flows of hydrothermal fluids.