|Figure 43 from the new BGS/DECC Weald Basin Jurassic Shale study.|
Today, the British Geological Survey (BGS) and the Department for Energy & Climate Change (DECC) published their report on the potential for the shales beneath south-east England to produce economic amounts of oil.
The diagram above comes from that report, though it is based on this article by Ottmann & Bohacs, published in AAPG Explorer earlier this year.
The pink blob in the diagram shows the combination of total organic carbon (TOC, typically at least 2%) and clay content (typically less than 35%) required of a shale to make it a commercially viable prospect in North America.
The black dots show the data acquired from shales in the Weald Basin.
From this, the report authors state that 'prospectivity would appear to be limited' (Andrews et al. 2014, p. 57).
You're not kidding!