Table T2. Petrographic features of analyzed granoblastic dikes, Expedition 335.
Sample |
Grain size* |
Minerals present |
Minerals analyzed |
Petrographic features, comments |
Shipboard TS#† |
|---|---|---|---|---|---|
| 335- | |||||
| 1256D-235R-1W-19 | Microcrystalline | Plagioclase, clinopyroxene, orthopyroxene, Fe-Ti oxides, amphibole | Plagioclase phenocrysts (core, rim), plagioclase matrix (core, rim), clinopyroxene matrix (core, rim), orthopyroxene matrix (core, rim), amphibole, magnetite matrix, ilmenite matrix, titanite | Presence of plagioclase phenocrysts; tiny oxide inclusions in pyroxenes; secondary amphibole overgrowth on clinopyroxene; secondary titanite overgrowth on ilmenite | |
| U1256D-Run12-RCJB-B | Cryptocrystalline | Plagioclase, clinopyroxene, orthopyroxene, Fe-Ti oxides, amphibole | Plagioclase phenocrysts (core, rim), plagioclase ghost (core, rim), plagioclase matrix (core, rim), clinopyroxene matrix, clinopyroxene inclusions in plagioclase, clinopyroxene in vein-like structure, clinopyroxene cluster, orthopyroxene matrix, orthopyroxene in vein-like structure, amphibole veins, amphibole cluster, amphibole overgrowth, magnetite matrix, ilmenite matrix | Clinopyroxene-orthopyroxene assemblages arranged in vein-like structures and clusters; presence of plagioclase phenocrysts; secondary amphibole in veins, clusters, and as overgrowth on clinopyroxene; sample contains magmatic veins‡ | 21 |
| U1256D-Run12-RCJB-Q | Microcrystalline to fine grained | Plagioclase, clinopyroxene, orthopyroxene, Fe-Ti oxides, amphibole | Plagioclase matrix (core, rim), clinopyroxene matrix (core, rim), clinopyroxene in band-like structure, orthopyroxene matrix (core, rim), orthopyroxene in band-like structure, amphibole inclusions in orthopyroxene, magnetite inclusions in orthopyroxene, magnetite matrix, ilmenite matrix | Very heterogeneous rock with marked foliation and banding due to parallel continuous or discontinuous bands dominated by orthopyroxene and clinopyroxene‡ | 25 |
| U1256D-Run12-RCJB-S | Microcrystalline to fine grained | Plagioclase, clinopyroxene, orthopyroxene, Fe-Ti oxides | Plagioclase phenocrysts (core, rim), plagioclase matrix, plagioclase in vein-like structure, clinopyroxene matrix (core, rim), clinopyroxene matrix (core, rim), orthopyroxene in vein-like structure, magnetite matrix, magnetite inclusions in orthopyroxene, ilmenite matrix, ilmenite inclusions in orthopyroxene | Sample contains two domains of different grain sizes, interpreted as former dike/dike contact; presence of plagioclase phenocryst‡ | 26 |
| U1256D-Run15-EXJB | Microcrystalline | Plagioclase, clinopyroxene, orthopyroxene, Fe-Ti oxides | Plagioclase phenocrysts (core, rim), plagioclase ghost (core, rim), plagioclase matrix, clinopyroxene matrix, orthopyroxene matrix, orthopyroxene cluster, magnetite cluster, magnetite matrix, ilmenite matrix | Very heterogeneous rock with foliation and bands where orthopyroxene and plagioclase is enriched; patchy clusters of orthopyroxene; many plagioclases with ghost cores; presence of plagioclase phenocrysts; high modal amount of Fe-Ti oxide with clusters of oxide and countless oxide inclusions in plagioclase and pyroxene‡ | 35 |
| U1256D-Run19-RCJB-D | Cryptocrystalline to microcrystalline | Plagioclase, clinopyroxene, orthopyroxene, Fe-Ti oxides, amphibole | Plagioclase phenocrysts (core, rim), clinopyroxene matrix (core, rim), orthopyroxene matrix (core, rim), amphibole, magnetite matrix, ilmenite matrix | Presence of plagioclase phenocrysts; presence of vein-like structures of mainly orthopyroxene; secondary amphibole overgrowth on clinopyroxene and in veins | |
* = grain sizes are related to the granoblastic matrix and were defined according to Teagle, Ildefonse, Blum, and the Expedition 335 Scientists, 2012: cryptocrystalline = <0.1 mm, microcrystalline = 0.1–0.2 mm, fine grained = >0.2–1 mm. † = shipboard thin section prepared from the same sample, ‡ = more petrographic information of this sample is available in Teagle, Ildefonse, Blum, and the Expedition 335 Scientists, 2012.
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