Monday, October 15, 2012

Geophysicst Mark Zoback On Fracking

Another terrific geology related talk on Generation Anthropocene. Geophysicist and shale gas expert Mark Zoback attempts to clear up the many misconceptions about fracking. He doesn't minimize or take lightly the negative impact of shale gas drilling, but rather puts it in a broader context. The greater risk of contaminating overlying aquifers is not from the act of hydraulic fracturing itself but from improper well construction and from leaky ponds which are constructed to store waste water that flows back out of the formation. This water may contain metals like iron or arsenic flushed by reaction with the shale. So actually according to him, there is nothing in the fracking fluid that is dangerous. But that fluid after reacting with the rock may become toxic.

Shale gas drilling companies don't have to disclose the exact composition of the fracking fluid as they have an exemption under the Clean Water Act. But perception does matter. As Mark Zobeck points out, there was growing support for nuclear power in the U.S. until the accident at Fukushima occurred. Public perception about risk can reverse major energy policy decisions regardless of the actual risk. If that is so, then why slow down or kill the shale gas goose? Perhaps it will be wiser to change policy and to come clean about fracking fluids.

Meanwhile, on the topic of shale gas in India,  a reader wrote in a comment on an earlier post I had written about Indian shale gas prospects:

US geological survey says the total shale gas reserves to be 6.1 Tcf, contrary to 63 Tcf by EIA. What are your views on this?

That is a major downgrade for Indian shale gas prospects. I could only suggest this possibility:

thanks Dakshina.. yeah.. i saw those figures.. hard to say but downward revisions are going on in many other basins around the world.. perhaps the actual recovery rates observed from shale gas wells i.e. their performance over a longer term have not been as good as initially projected..leading to downward revision of technically recoverable resources in other areas as well.. or maybe it has to do with the reassessment of the basic geological data.. can't say for sure without reading more details.. ///

Also worth reading is another article by Mark Zoback on the seismic risk posed by shale gas drilling and waste water disposal.


  1. Yeah this was a terrific talk. I'm a big fan of the Generation Anthropocene Podcast - Interestingly enough, I'm good friends with Mike Osbourne (also coral paleoclimatologist by training) and have also attended ~4 talks by Mark Zoback on various topics (excellent speaker of course).

    On topic, where is most of India's shale located?

  2. Kaustubh- yeah, the one by Jon Payne on defining Anthropocene as a stratigraphic horizon was also great..In India most of the onshore shale basins prospects are from Cambay, Krishna Godavari, Cauvery basin and Damodar valley.. offshore possibly Cambay and Krishna Godavari..