Evaluation and re-understanding of the global natural gas hydrate resources

Abstract

Natural gas hydrate (NGH) has been widely considered as an alternative to conventional oil and gas resources in the future energy resource supply since Trofimuk’s first resource assessment in 1973. At least 29 global estimates have been published from various studies so far, among which 24 estimates are greater than the total conventional gas resources. If drawn in chronological order, the 29 historical resource estimates show a clear downward trend, reflecting the changes in our perception with respect to its resource potential with increasing our knowledge on the NGH with time. A time series of the 29 estimates was used to establish a statistical model for predict the future trend. The model produces an expected resource value of 41.46 × 1012 m3 at the year of 2050. The statistical trend projected future gas hydrate resource is only about 10% of total natural gas resource in conventional reservoir, consistent with estimates of global technically recoverable resources (TRR) in gas hydrate from Monte Carlo technique based on volumetric and material balance approaches. Considering the technical challenges and high cost in commercial production and the lack of competitive advantages compared with rapid growing unconventional and renewable resources, only those on the very top of the gas hydrate resource pyramid will be added to future energy supply. It is unlikely that the NGH will be the major energy source in the future.

Parameter Optimization Study of Gas Hydrate Reservoir Development Based on a Surrogate Model Assisted Particle Swarm Algorithm

“…Moridis et al investigated the depressurization performance of the hydrate bearing layers in Mallik area and Alaska North Slope. The results show that the dissociation area is mainly located around the well, and the gas production is low only through depressurization method [29,30]. Zhang et al investigated the decomposition conditions of methane hydrate and the effect of hydrate saturation on the methane hydrate dissociation, and the results are similar to those of Moridis [32][33][34].…”

“…China has implemented two trial production tests of hydrate bearing layers in the Shenhu area, and the average daily gas production rate of the second trial production test is 2:87 × 104 m 3 , which is quite lower than the minimum gas production rate required for commercial development [27][28][29]. Moridis et al investigated the depressurization performance of the hydrate bearing layers in Mallik area and Alaska North Slope.…”

Economic Critical Resources for the Industrial Exploitation of Natural Gas Hydrate

“…The gap between the maximum value and the minimum value is about four orders of magnitude. This is mainly due to the lack of consensus among different researchers on the nature, occurrence and even a clear definition of NGH resources, as well as the methods and data used for evaluation (Pang et al, 2021). Most resource estimates have shown a downward trend over time, with the exception of Klauda and Sandler (2005), whose estimate includes very deep and dispersed hydrates that are usually not taken into account by other researchers.…”

Numerical Investigation of the Gas Production Efficiency and Induced Geomechanical Responses in Marine Methane Hydrate-Bearing Sediments Exploited by Depressurization through Hydraulic Fractures

“…They are usually found in hydrate-stable zones characterized by low temperatures and high pressures. − In these zones, the thermodynamic equilibrium can be guaranteed so that methane hydrate dissociation is inhibited. The natural occurrence of methane hydrates is usually located in permafrost and marine sediments . Boswell and Collett estimated that there is about 10 5 TCF methane in the reserve, while Moridis et al estimated the range to be between 10 15 and 10 18 ST m 3 .…”