Figure F46. MgO vs. K2O showing the small deviation from differentiated normal mid-ocean-ridge basalt (N-MORB) glass compositions of the fresh basalts of Hole 1224D (large black dots). Samples from Cores 200-1224D-1R to 3R are from the upper flow, and Cores 4R and 5R are from the lower flow. Also plotted are compositions of N-MORB glasses (small red dots) from the Pacific-Antarctic East Pacific Rise (Y. Niu, P. Castillo, and J. Natland, unpubl. data). These exemplify the range of differentiation from high to low MgO contents and low to high TiO2 contents typical for basalts of the East Pacific Rise. Lines link three samples with slightly high K2O to less altered samples.

Figure F46. MgO vs. K₂O showing the small deviation from differentiated normal mid-ocean-ridge basalt (N-MORB) glass compositions of the fresh basalts of Hole 1224D (large black dots). Samples from Cores 200-1224D-1R to 3R are from the upper flow, and Cores 4R and 5R are from the lower flow. Also plotted are compositions of N-MORB glasses (small red dots) from the Pacific-Antarctic East Pacific Rise (Y. Niu, P. Castillo, and J. Natland, unpubl. data). These exemplify the range of differentiation from high to low MgO contents and low to high TiO₂ contents typical for basalts of the East Pacific Rise. Lines link three samples with slightly high K₂O to less altered samples.