Case Study 4 Mallik

Case Study 4 Mallik 2002 (Hydrate Production in Permafrost)... 

Chapter 7 discusses in situ hydrates in the oceans and permafrost. Seven key concepts are presented for hydrates in nature. These concepts are illustrated in four field case studies for hydrate assessment (Blake Bahama Ridge, Hydrate Ridge) and production (Messoyakha and Mallik, 2002). 

The most recent well log summaries for hydrates is that by Anderson et al. (2005) and the log summary in the Mallik 2002 case study by Collett et al. (2005). While a brief overview is presented below and exemplified in the Mallik 2002 case study, the reader interested in details is encouraged to review the above two documents for a thorough exposition of hydrate open hole well logging. 

The Mallik case study (Figures 7.36 and 7.37) provides the best example of well logs in a permafrost hydrate reservoir, followed closely by the Leg 204 (Figures 7.26 and 7.27) example for ocean hydrates. All four of the case studies for field hydrates have associated logs. 

A field test, such as the Mallik 2002 case study, is perhaps the best analog of hydrate dissociation in a reservoir. However, the Mallik 2002 project cost many man years and approximately US 22,000,000. Even with such a large cost, there was still concern about the data obtained, and how representative the transient data would be for long-term production. 

New case studies summarizing Hydrate Ridge and Mallik 2002 test drillings... 

Nath, B., Berner, Z., Mallik, S.B. et al. (2005) Characterization of aquifers conducting groundwaters with low and high arsenic concentrations a comparative case study from West Bengal, India. Mineralogical Magazine, 69(5), 841-54. 

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