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A GLOBAL OUTLOOK ON METHANE GAS HYDRATES
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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).
BSR
TWO-WAY TRAVEL TIME, IN SECONDS
3.8
4.0
4.2
4.4
4.6
Site 994
Site 995
Site 997
SSW
NNE
0 1 2 3 4 5 km
Blake Ridge
B
C
A