Identification of Natural Gas Hydrates in Blocks 25a, 25b, 26 and 27 Offshore Trinidad Using Available Well Log Data

Natural gas hydrates can be found in conventional hydrocarbon depositional environments such as clastic marine sediments, siltstones and unconsolidated sands and in oceanic environments for reservoir pressures greater than 663 psi (46 bars) and temperatures less than 20 °C. These conditions are found in the deep water (> 300 m) acreage off the South East coast of Trinidad. Natural gas hydrates have been recovered in this area during drilling and seismic data have shown that there may be deposits in some areas. In this study we reviewed all the available borehole data and employed well log interpretation techniques to identify natural gas hydrates in the deep water acreage blocks 25 a, 25 b, 26 and 27 off the Trinidad South East coast. The analysis of well log data for the given depths did not present evidence to suggest the presence of natural gas hydrates in Blocks 25 a, 25 b, 26 and 27. In this paper we present our analysis of the data available and recommend the formation depths which should be logged in during the deep water exploration drilling to confirm the seismic data and core data which indicate the presence of natural gas hydrates in these blocks.