As a rather interesting footnote, I found a cutout from The San Juan Star which my father had placed in the book. The article, dated May 3, 1969 was by Harold Lidin:
Oil exploration in the Dominican Republic has boomed with the start of off-shore research along the northeast coast, and the beginning of intensive drilling in the republics arid southwest. The operations involve two large US firms and a group of Puerto Rican investors. The offshore effort features the use by the Tenneco Oil Co. of the survey ship "Artic Seal" to test the oil bearing potential of a submarine shelf in the Bay of Samana area.
Regarding the newspaper article, see also this and this.