Unknown
PANGAEA
In:
Supplement to: Harrison, R K; Merriman, Richard J; Evans, Jane; Hutchison, Dawn; Davis, A E; Holmes, K A; Joseph, Philippe; Judge, V A; Wheatley, C W (1984): Petrology, mineralogy, and chemistry of basaltic rocks: Leg 81. In: Roberts, DG; Schnittker, D; et al. (eds.), Initial Reports of the Deep Sea Drilling Project, Washington (U.S. Govt. Printing Office), 81, 743-774, https://doi.org/10.2973/dsdp.proc.81.129.1984
Publication Date:
2023-05-12
Description:
We detail the petrography and mineralogy of 145 basaltic rocks from the top, middle, and base of flow units identified on shipboard along with associated pyroclastic samples. Our account includes representative electron microprobe analyses of primary and secondary minerals; 28 whole-rock major-oxide analyses; 135 whole-rock analyses each for 21 trace elements; 7 whole-rock rare-earth analyses; and 77 whole-rock X-ray-diffraction analyses.
These data show generally similar petrography, mineralogy, and chemistry for the basalts from all four sites; they are typically subalkaline and consanguineous with limited evolution along the tholeiite trend. Limited fractionation is indicated by immobile trace elements; some xenocrystic incorporation from more basic material also occurred. Secondary alteration products indicate early subaerial weathering followed by prolonged interaction with seawater, most likely below 150°C at Holes 552, 553A, and 554A. At Hole 555, greenschist alteration affected the deepest rocks (olivine-dolerite) penetrated, at 250-300°C.
Keywords:
Deep Sea Drilling Project; DSDP
Type:
Dataset
Format:
application/zip, 21 datasets
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