Geochemistry of basalts from the Dumisseau Formation, southern Haiti: implications for the origin of the Caribbean Sea crust

Details Geochemistry of basalts from the Dumisseau Formation, southern Haiti: implications for the origin of the Caribbean Sea crust Geochemistry of basalts from the Dumisseau Formation, southern Haiti: implications for the origin of the Caribbean Sea crust

Mar 1988

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1988e%26psl..87..423s&link_type=abstract

Earth and Planetary Science Letters, Volume 87, Issue 4, p. 423-437.

Computer Science

14

Scientific paper

Basalt and diabase from the Cretaceous Dumisseau Formation, southern Haiti have Mg-numbers of 43-63, TiO2 contents of 1.6-3.9% and La abundances of 3.6-15.3 ppm. La/Ta ratios average 10, and indicate that the basalts are oceanic in character, distinct from the arc associations forming the northern part of Haiti. Oldest lavas have low TiO2 (1.6%) and are LREE-depleted, similar to N-MORBs, whereas overlying lavas have higher TiO2 (2-3.9%) and are LREE-enriched, similar to E-MORBs or hotspot basalts. 87Sr/86Sr ratios vary from 0.70280 to 0.70316, 143Nd/144Nd from 0.512929 to 0.513121, and 206Pb/204Pb from 19.00 to 19.27. LREE-depleted lavas have high 143Nd/144Nd (0.51309-0.51310) typical of MORBs, whereas 143Nd/144Nd in the LREE-enriched lavas varies widely (0.512929-0.513121).
Chemical features of the Dumisseau basalts are equivalent to those of Caribbean seafloor basalts recovered on DSDP Leg 15, and support the contention that the Dumisseau is an uplifted section of Caribbean Sea crust. Oldest lavas are analogous to MORB-like basalts cored at Leg 15 Sites 146, 150, 152 and 153, and the overlying lavas are analogous to incompatible-element-enriched basalts cored at Site 151 on the Beata Ridge. Isotopic compositions of the Dumisseau basalts overlap with those of the eastern Pacific Galapagos and Easter Island hotspots. However, the presence of N-MORB basalts in the lower part of the Dumisseau and at the majority of Leg 15 Sites indicates that the anomalously thick Caribbean crust probably did not originate as a hotspot-related basaltic plateau, but may have been generated by on-ridge or near-ridge hotspot magmatism.

Affiliated with

Also associated with

No associations

Rating

Geochemistry of basalts from the Dumisseau Formation, southern Haiti: implications for the origin of the Caribbean Sea crust does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Geochemistry of basalts from the Dumisseau Formation, southern Haiti: implications for the origin of the Caribbean Sea crust, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Geochemistry of basalts from the Dumisseau Formation, southern Haiti: implications for the origin of the Caribbean Sea crust will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1673787