It is increasingly claimed that the world is entering a ‘golden age of gas’, with the exploitation of unconventional resources expected to transform gas markets around the world. But the future development of these resources is subject to multiple uncertainties, particularly with regard to...

Estimates of technically recoverable shale gas resources remain highly uncertain, even in regions with a relatively long history of shale gas production. This paper examines the reasons for these uncertainties, focussing in particular on the methods used to derive resource estimates. Such...

This review paper summarises and evaluates the evidence regarding four issues that are considered to be of critical importance for future global oil supply. These are: a) how regional and global oil resources are distributed between different sizes of field; b) why estimates of the recoverable...