Southeastern Section - 64th Annual Meeting (19–20 March 2015)

Paper No. 3
Presentation Time: 8:00 AM-12:00 PM


RIVERA LASTRA, Imaryarie, PO Box 51169, Toa Baja, PR 00949 and CHIZMADIA, Lysa, Department of Geology University of Puerto Rico - Mayaguez, Call Box 9000, Mayaguez, PR 00681,

This investigation is focused on a small outcrop of igneous rocks on the island of Anguilla. The purpose of this project is to study the nature of three samples and characterize them. This is important because they have not been studied in detail before. Then, they are going to be compared with rocks from nearby Saint Bartholomew and Saint Martin. The three islands are likely to share a geologic history and basement because of their proximity and bathymetry between them. The main hypothesis of this project is that these rocks are related to the extrusive igneous rocks from Saint Bartholomew and Saint Martin. It was confirmed that the samples from Anguilla are of igneous origin; they are probably a highly weathered basalt, porphyritic basalt and porphyritic andesite. Only one of the three samples 14AN-03 is probably related to both islands, St. Barths and St. Martin, because it is similar in composition and texture. The samples 14AN-01 and 14AN-02 is probably related only to St. Barths and reflects a lava flow that was exposed to water during its eruption.