Open source FWI, I mean geoscience

I'm being a little cheeky. Yesterday's Open Source Geoscience workshop at EAGE was not really only about full waveform inversion (FWI). True, it was mostly about geophysics, but there was quite a bit of new stuff too.

But there was quite a bit on FWI.

The session echoed previous EAGE sessions on the same subject in 2006 and 2012, and was chaired by Filippo Broggini (of ETH Zürich), Sergey Fomel (University of Texas), Thomas Günther (LIAG Hannover), and Russell Hewett (Total, unfortunately not present). It started with a look at core projects like Madagascar and OpendTect. There were some (for me) pretty hard core, mathematics-heavy contributions. And we got a tour of some new and newish projects that are seeking users and/or contributors. Rather than attempting to cover everything, I'm going to exercise my (biased and ill-gotten) judgment and focus on some highlights from the day.

Filippo Broggini started by reminding us of why Joe Dellinger (BP) started this recurrent workshop a decade ago. Here's how Joe framed the value of open source to our community:

The economic benefits of a collaborative open-source exploration and production processing and research software environment would be enormous. Skilled geophysicists could spend more of their time doing innovative geophysics instead of mediocre computer science. Technical advances could be quickly shared and reproduced instead of laboriously re-invented and reverse-engineered. Oil companies, contractors, academics, and individuals would all benefit.

Did I mention that he wrote that 10 years ago?

Lessons learned from the core projects

Kristofer Tingdahl (dGB) then gave the view from his role as CEO of dGB Earth Sciences, the company behind OpendTect, the free and open source geoscience interpretation tool. He did a great job of balancing the good (their thousands of users, and their SEG Distinguished Achievement Award 2016) with the less good (the difficulty of building a developer community, and the struggle to get beyond only hundreds of paying users). His great optimism and natural business instinct filled us all with hope.

The irrepressible Sergey Fomel summed up 10 years of Madagascar's rise. In the journey from v0.9 to v2.0, the projects has moved from SourceForge to GitHub, gone from 6 to 72 developers, jumped from 30 to 260 reproducible papers, and been downloaded over 40 000 times. He also shared the story of his graduate experience at Stanford, where he was involved in building the first 'reproducible science' system with Jon Claerbout in the early 1990s. Un/fortunately, it turned out to be unreproducible, so he had to build Madagascar.

It's not (yet?) a core project, but John Stockwell (Colorado School of Mines) talked about OpenSeaSeis and barely mentioned SeismicUnix. This excellent little seismic processing project is now owned by CSM, after its creator, Bjoern Olofsson, had to give it up when he went to work for a corporation (makes sense, right? o_O ). The tool includes SeaView, a standalone SEGY viewer, as well as a graphical processing flow composer called XSeaSeis. IT prides itself on its uber-simple architecture (below). Want a gain step? Write and you're done. Perfect for beginners.

Jeffrey Shragge (UWA), Bob Clapp (SEP), and Bill Symes (Rice) provided some perspective from groups solving big math problems with big computers. Jeff talked about coaxing Madgascar — or M8R as the cool kids apparently refer to it — into the cloud, where it can chomp through 100 million core hours without setting tings on fire. This is a way for small enterprises and small (underfunded) research teams to get big things done. Bob told us about a nifty-looking HTML5 viewer for subsurface data... which I can't find anywhere. And Bill talked about 'mathematical fidelty'. and its application to solving large, expensive problems without creating a lot of intermediate data. His message: the mathematics should provide the API.

New open source tools in geoscience

The standout of the afternoon for me was University of Vienna post-doc Eun Young Lee's talk about BasinVis. The only MATLAB code we saw — so not truly open source, though it might be adapted to GNU Octave — and the only strictly geological package of the day. To support her research, Eun Young has built a MATLAB application for basin analysis, complete with a GUI and some nice visuals. This one shows a geological surface, gridded in the tool, with a thickness map projected onto the 'floor' of the scene:

I'm poorly equipped to write much about the other projects we heard about. For the record and to save you a click, here's the list [with notes] from my 'look ahead' post:

  • SES3D [presented by Alexey Gokhberg], a package from ETHZ for seismic modeling and inversion.
  • OpenFOAM [Gérald Debenest], a new open source toolbox for fluid mechanics.
  • PyGIMLi [Carsten Rücker], a geophysical modeling and inversion package.
  • PySIT [Laurent Demanet], the Python seismic imaging toolbox that Russell Hewett started while at MIT.
  • Seismic.jl [Nasser Kazemi] and jInv [Eldad Haber], two [modeling and inversion] Julia packages.

My perception is that there is a substantial amount of overlap between all of these packages except OpenFOAM. If you're into FWI you're spoilt for choice. Several of these projects are at the heart of industry consortiums, so it's a way for corporations to sponsor open source projects, which is awesome. However, most of them said they have closed-source components which only the consortium members get access to, so clearly the messaging around open source — the point being to accelerate innovation, reduce bugs, and increase value for everyone — is missing somewhere. There's still this idea that secrecy begets advantage begets profit, but this idea is wrong. Hopefully the other stuff, which may or may not be awesome, gets out eventually.

I gave a talk at the end of the day, about ways I think we can get better at this 'openness' thing, whatever it is. I will write about that some time soon, but in the meantime you're welcome to see my slides here.

Finally, a little time — two half-hour slots — was set aside for discussion. I'll have a go at summing that up in another post. Stay tuned!

BasinVis image © 2016 Eun Young Lee, used with permission. OpenSeaSeis image © 2016 Center for Wave Phenomena