Gas hydrates: Frozen Natural Gas
Repository
Kumar Abhishek Singh (Author)
Gogineni Sudarsan Sai, Prem Shah, PDPU

A Fuel to Ignite India's Energy Crisis
It looks like chunks of ice — but put a flame to
it and it goes ablaze.

Introduction
The next game-changer for the energy sector
A total volume of ~1900 trillion meter
cube of methane gas, stored in the form
of gas-hydrates, has been
prognosticated within the vast exclusive
economic zone (EEZ) of India. This
volume of gas is greater than 1500 times
of India’s present natural gas reserve.

Agenda or Summary Layout
About Gas Hydrate
Technology for the exploration of Gas Hydrates
Methodologies for exploitation of Gas Hydrates
Gas Hydrate production, research, development
Barriers AND Conclusion
1.
2.
5.
3.
4.
6.
Example from KG Basin, India

About Gas Hydrate
An ice-like crystalline form of water and low molecular weight gas (e.g.,
methane, ethane, carbon dioxide). Also phrased as "Fiery ice“.

Structural transition
Gas composition and pressure effect

Where and How Does Gas Hydrate
Form?
Gas hydrate is stable in the underlying sediments to a depth of about
225 m below the seafloor. Also gas hydrate is stable from about 200 to
600 m within the permafrost and from 600 m to ~1100 m beneath the
permafrost.

In environments in which the temperature is 0 degree Celsius, gas
hydrate will form only if the atmospheric pressure is 23 times normal
atmosphere (i.e., 23 atm). Under normal atmospheric pressure, gas
hydrate will only exist in stable form if the temperature is -80 degree
Celsius or below.

Global Occurrence & Distribution of
Natural Gas Hydrates
The huge volume (1-120 x 1015 m3) of methane trapped within global
reserve. Location of known and inferred gas hydrate occurrences (89
sites) in deep marine and arctic permafrost environments.

India’s position
If 1% of the Prognosticated potential resource which is estimated
at 1894 TCM, can be exploited, the exploitable resources would
give rise to 3100 TCM of methane since at standard temperature
and pressure per cubic meter of hydrate yields on an average
164 m3 of methane and 0.8 m3 of water.

Technology used for the exploration
of Gas Hydrates
The bottom of gas hydrate stability zone (GHSZ) is strong reflector of
seismic waves. This reflector is named as bottom simulating reflector
(BSR) in the seismic section. Enhanced reflections below the BSR.

Confirm the presence of Gas Hydrate
Microstructural model of hydrate bearing sediments.

Time to be Practical
Comparison of measured and modelled seismic velocities in
hydrate bearing zone of a Canadian well

Example from KG Basin, India
An anomalous reflector was first identified in 1970 that mimics the sea-
bottom. But since it was not twice the travel-time of acoustic signal to
the sea-bottom, it could not be designated as a multiple reflection.

Confirm by borehole image and core
from Krishna-Godavari region.
NGHP-01-10 is one of the richest marine gas hydrate
accumulations ever discovered

Methodologies for exploitation of
Gas Hydrates
De-pressurization and Thermal dissociation (e.g. McKenzie delta
Canadian Permafrost Area (2007))

An option to reduce carbon
emissions
CO2 substitution

Inhibitor Injection Method
Hydrophobic amino acids and methanol

Gas Hydrate production research and
development
USA, Japan, India, Canada, the United Kingdom, Germany,
Brazil, Norway, Russia, China, Korea, etc., are the countries
actively involved in research and development of gas
hydrates.
Mallik 2002 Gas Hydrate Well Research Programme and
attempted the first gas production test. Thermal
stimulation by hot water circulation was tried in the test.
During the 123.7 hour operation, 470m3 gas was produced
from the formation.

India’s Expedition Overview
Reconnaissance surveys carried out by DGH in the East
Coast and Andaman Deepwater areas in 1997 deciphered
the most promising areas for Gas Hydrates.
Under the National Gas Hydrate Program (NGHP),
Discovered gas hydrate in numerous complex geologic
settings and collected an unprecedented number of gas
hydrate cores (more than 2800 m from 21 sites and 39
holes).

Barriers
One reason why developing nations hesitate to invest in
gas hydrate research is the resource’s uncertain economic
viability.
As there are not many wells drilled for methane extraction,
it’s extremely difficult to assess the true amount of
methane hydrate deposits.
Effective heat transfer from well to the reserve.

Conclusion
"How long can the gradual warming go on before the
methane gets out? Nobody knows, but the longer it goes
on, the closer we get to playing Russian roulette.“
If exploration moves on to gas production, the
geopolitical, economic and environmental repercussions
will be enormous — and developing nations could assume
new positions on a transformed global energy map.

References
[1] http://www.scidev.net/global/energy/feature/developing-nations-
join-r-d-race-for-gas-hydrates.html
[2] http://info.drillinginfo.com/gas-hydrates-keep-the-lights-on/
[3] http://www.eai.in/ref/ae/afm/afm.html
[4] http://www.rdmag.com/articles/2011/06/future-fossil-fuel
[5] http://www.dghindia.org/NonConventionalEnergy.aspx?tab=0
[6] http://woodshole.er.usgs.gov/project-pages/hydrates/primer.html
[7]http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%2
0name&filter=gas+hydrate
(8) Collet, A. Johnson, C. Knapp, and R. Boswell, eds., Natural gas
hydrates—Energy resource potential and associated geologic hazards:
AAPG Memoir 89, p. 146– 219.
(9) Rappel, C., 2007, Tapping methane hydrates for unconventional
natural gas, Elements, 3(3), 193-199.