Sable Island Deep Test of Scotian Shelf: ABSTRACT

Abstract

Mobil Oil No. 1 Sable Island was drilled to a total depth of 15,106 ft on the Scotian shelf of the Canadian Atlantic offshore. It was the first deep test in the region. The well, on the outer shelf, 190 mi east of Halifax, Nova Scotia, used historic Sable Island as a drilling platform. The exploratory test was drilled into the Lower Cretaceous; thus, it not only documented the extension of the submerged Atlantic coastal plain south of Nova Scotia, but also indicated the presence of a thick Cretaceous sedimentary succession in the region. The well section is predominantly marine clastic rock composed of 4,050 ft of Tertiary and Quaternary, and 11,056 ft of Cretaceous strata. These sequences can be subdivided into 11 units on the basis of sandstone percentage, paleontologic data, and other lithologic criteria. These units indicate the occurrence on this part of the Scotian shelf of fluctuating, mainly marine Cretaceous and Tertiary deposition in littoral to bathyal water depths. Encouraging but noncommercial gas shows were tested in several zones, particularly in the Lower Cretaceous. A trace of oil was recovered on a test at total depth. Porous sandstone is abundant through most of the section. The discovery by the Sable Island well of a thick, marine, Cretaceous-Tertiary section with indications of hydrocarbon generation and potential reservoir beds greatly enhances oil and gas prospects in the Canadian Atlantic offshore and the Scotian shelf in particular. End_of_Article - Last_Page 858------------