Unknown
PANGAEA
In:
Supplement to: Barrett, T J; Friedrichsen, Hans (1983): Oxygen- and hydrogen-isotope composition of some basalts from Deep Sea Drilling Project Hole 504B, Costa Rica Rift, Legs 69 and 70. In: Cann, JR; Langseth, MG; Honnorez, J; Von Herzen, RP; White, SM; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 69, 637-642, https://doi.org/10.2973/dsdp.proc.69.137.1983
Publication Date:
2023-06-27
Description:
Whole-rock basalt samples from the upper half of Deep Sea Drilling Project Hole 504B have oxygen-isotope compositions typical of mid-ocean-ridge basalts which have experienced a moderate degree of low-temperature alteration by sea water. By contrast, d18O values in the lower half of the hole correspond to basalts which have experienced almost no detectable oxygen-isotope alteration. These observations suggest that the overall water/rock ratio was lower in the lower half of the drilled crust. A correlation between d18O values and 87Sr/86Sr ratios suggests that the water/rock ratio, rather than temperature variation, was the main factor determining basalt d18O values. Hydrogen-isotope data appear to be consistent with a low water/rock ratio in the lower part of the crust.
Keywords:
69-504B; 70-504B; Alteration; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Event label; Glomar Challenger; Leg69; Leg70; Lithology/composition/facies; Mass spectrometry; Piece; Sample code/label; Sample ID; δ18O; δ Deuterium
Type:
Dataset
Format:
text/tab-separated-values, 122 data points
Permalink
|
Location |
Call Number |
Expected |
Availability |
