Gas hydrates (HG) are a source of hydrocarbons with potential for future exploration. The
storage of natural gas (mainly methane), in the form of cell (clathrate), shows volume of
interest: 1 m3 of saturated hydrates (under ideal temperature and pressure) has 164 m3 of
equivalent methane gas. These numbers point to hydrates as the largest reserves of known fossil
resources since their discovery in Siberia in the 1960s. In the present context, one of the main
focuses of the research is the to develop and improve hydrate extraction and also their transport
techniques, partly due to the high extraction costs and the potential environmental impacts.
Given this, geophysical studies combined with geology are of great importance for reserves
feasibility. Projects occur around the world in search of economical extraction of gas hydrates,
however taking into account geological and geophysical information, including those related to
the occurrence of hydrates in Brazilian territory. Currently, there are a few hydrate-related
surveys in Brazil despite promising resources at Pelotas and Foz do Amazonas Basins, the latter
one is the focus of this paper. Such basin has approximately 13 trillion m3 of in situ gas
compared to Brazilian reserves (total) of 696 billion m3 present in clathrates. Geophysical and
geological studies conducted in the Foz do Amazonas Basin have detected occurrences of gas
hydrates at region known as the Cone (or Fan) of the Amazon. These occurrences were located
by very distinct characteristics such as BSR (Bottom Seismic Reflection) and fault’s (or
fracture’s) identification, which are fluid migration routes. Despite the importance of this
discovery for the Amazon Region, further studies are still needed. Given this, it is necessary
more research in the area, taking into account the gas potential, but without forgetting the
environmental, economic and exploratory issues.
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