FROZEN HEAT | Volume 2

Blake Ridge

A

Figure 2.12: Gas hydrate exploration at the Blake Ridge. The Blake Ridge is a large sediment drift off the eastern coast of North America (A and red circle in B). In 1995, it was the site of the first extensive marine scientific expedition dedicated to investigate the hypothesis that anomalous seismic features known as “bottom simulating reflectors” (BSRs) reflected the occurrence of gas hydrates (C). The 1995 drilling program confirmed that a large volume of gas hydrate was broadly dispersed through a thick section and over a large area within primarily fine-grained sediments. More recently, a broader evaluation of the Atlantic Margin (B) suggests that the areas most prospective for gas hydrate resource evaluation (warm colors) may occur further to the north where shallow sediments are inferred to be more sand-rich. (A) After BOEM (2012); (B) Courtesy USGS; (C) Adapted from Paull, C., Matsumoto, R., Wallace, P., and Dillon, W. (2000).

B

Site 994

Site 995

Site 997

SSW

NNE

3.8

4.0

BSR

4.2

4.4

4.6

TWO-WAY TRAVEL TIME, IN SECONDS

C

0 1 2 3 4 5 km

A GLOBAL OUTLOOK ON METHANE GAS HYDRATES 51