GD
Geodynamics
The Sassy Scientist

The Sassy Scientist

I am currently employed at a first tier research institute where I am continuously working with the greatest minds to further our understanding of the solid Earth system. Whether it is mantle or lithosphere structure and dynamics, solid Earth rheology parameters, earthquake processes, integrating observations with model predictions or inversions: you have read a paper of mine. Even if you are working on a topic I haven’t mentioned here, I still know everything about it. Do you have any problems in your research career? I have already experienced them. Do you struggle with your work-life balance? Been there, done that. Nowadays, I have only one hobby: helping you out by answering the most poignant questions in geodynamics, research and life. I am waiting for you right here. Get inspired.

The Sassy Scientist – Publishing Lulls

The Sassy Scientist – Publishing Lulls

Every week, The Sassy Scientist answers a question on geodynamics, related topics, academic life, the universe or anything in between with a healthy dose of sarcasm. Do you have a question for The Sassy Scientist? Submit your question here or leave a comment below.

Through an overwhelmingly frustrating waiting period, first due to an editor that went AWOL with an unresponsive email account as a result, and then due to my interlude on the earthquake cycle, Candide furiously asks:


My paper is taking forever to be published. Do you know any way to speed up the process?


Dear Candide,

Let’s suppose I’m an editor for some journal and I have been awarded your manuscript to review. After finally having found some reviewers that accepted to do this job, I have another twenty papers I am supervising. Whilst waiting on reviews to come back, I’ve got journal administrators on my back because my reject/accept quotum is way too high; I’ve been disallowing a lot of papers. Mostly because of a lack of … let’s call it “improvement of scientific understanding”. Do you think you’re the only one who isn’t particularly thrilled by the peer review process? Join the club. Disgruntled due to the duration of the process? Write a better paper. Irritated by limited response? Yes, you’re the only one sending me an email. The only one. You’re unique in the world.

I got a little bit side-tracked there. Let’s regroup. Sending a myriad of emails to editors and journal administrators will not always result in a positive outcome for you. Unfortunately, there simply isn’t a proper way to speed up the process, other than submitting an absolute pearl of a paper in the first place. As I am sure you thought you did. Even though job security for early career scientist is … let’s say not great, and productivity is a major factor in the decision process, there are no widespread – nor outspoken – special conditions for papers submitted by early career scientists. Since it is certainly fair to consider that the priority of shuffling these papers through the system is fairly low – I mean, other scientists who also depend on publication lists to obtain grands and such also want their papers published asap – maybe it is not unreasonable to assume that official journal guidelines will not change on this principle. It’s just another one sliding somewhere in the never-ending pile. You’re then left dependent on the editor-at-large. Exercising patience is the only thing left to do. Whilst conferences, and especially workshops, have recognized the need for additional focus on (mostly) PhD students, we’re left hanging by the journals. Through the promise of optimism in the background, that this sour taste of a lack of early career scientist sympathy will be washed away by the sweet taste of expeditious peer review and knowledgeable legislation, the reality of a pragmatic solution is wavering. I wonder whether the EGU journals cannot take the lead on improving this…

Yours truly,

The Sassy Scientist

PS: This post was written whilst waiting on my own editor to respond… Thanks Iris. Bosses, right?

The Sassy Scientist – Incompetency Check

The Sassy Scientist – Incompetency Check

Every week, The Sassy Scientist answers a question on geodynamics, related topics, academic life, the universe or anything in between with a healthy dose of sarcasm. Do you have a question for The Sassy Scientist? Submit your question here or leave a comment below.

After reading up on many of the aspects described for the earthquake cycle that were oftentimes presented through fundamental observations and theories over the past weeks, Oleg found himself in a state of self-reflection and asked:


I’m afraid I’ve forgotten all my maths and physics skills during my PhD in geodynamics. Should I be worried?


Dear Oleg,

I would be. How did you get through those years? I gather that you must be using some numerical model, since analogue modelling, seismology and geodesy (yes … even geology) requires at least some basic maths and/or physics skills. Thank God just about anyone can use numerical models. You must be working with one of those standard black-box numerical codes that also magically produces statistical measurements on how well your models perform. It’s a good thing that the point of doing a PhD is just about blindly producing some papers by employing some methodology that you can use. Or is it about underpinning observations/theories/concepts through the fundamentals (i.e., maths and physics)? Have you been able to make a decent interpretation of what your model means? Or is that something your supervisor or co-authors have constantly done? If the former I wouldn’t worry too much. If it’s the latter it sure sounds exceptionally irresponsible from your supervisor and promotor.

It’s probably not as bad as you ponder right this moment. Everybody — i.e., every starting scientist — has a tendency to underestimate their skills and you’ve probably remembered more details uttered during your undergrad courses you’ve slept through than you give yourself credit for. I suppose that, if you’re terribly in despair, you just need to take some time and go back to look up some of the books you must have used in your undergrad years: brush up your basic linear algebra and vector analysis. The world’s a tensor; deal with it. To make it worth while, you might want to look up isostasy, Euler poles, continuum mechanics and statistics. Grasping these concepts provides you with the fundamentals so that you can study geodynamics. You’ll find that you have applied some, or all, of these at some point in your research. An abundance of researchers nowadays perform all kinds of fancy statistical tricks, employing fancy numerical codes and have a fancy way of writing it down. The one thing they lack is actual, fundamental understanding. Don’t be a lackey of the — intentionally — ignorant, an acolyte of the small-minded, a minion of the depraved. Raise your voice above the murmur of mediocrity (which sadly is the base level for most publications nowadays). Just dissect your previous work and outline shortcoming in maths and physics. Scrutinise the text books, and I’m sure you’ll get there. Remember that no one knows everything. As long as you are honest with yourself about what you do and don’t know or understand, you can have fair discussions about your research and you will learn. In the end, that’s all that research is: learning and learning what you do not know (yet). Actually, the pinnacle of science is overcoming our ignorance.

Yours truly,

The Sassy Scientist

PS: This post was written after being shaken and stirred about the impossible possibility which is forgetting math and physics during a PhD in geodynamics.

The Sassy Scientist – Earthquake Exoteries Nr. VII

The Sassy Scientist – Earthquake Exoteries Nr. VII

Every week, The Sassy Scientist answers a question on geodynamics, related topics, academic life, the universe or anything in between with a healthy dose of sarcasm. Do you have a question for The Sassy Scientist? Submit your question here or leave a comment below.

In a comment on a post about the key papers in geodynamics, the Curmudgeonly Commenter asked:


Could you please point out some exceptionally important papers in geodynamics and tell us something interesting about the history of the field?


Dear CC,

I feel like a lifetime has passed since I first started answering your question. I hope you are satisfied with the extent of the response. Please don’t ever ask me a question again. Really, I’ve got some important research to do. This is supposed to be some light-hearted banter, not some in-depth material acquisition you can put in your Introductions.

Additional spatio-temporal complexities
Of course, by now you realise that we must know everything about the earthquake cycle. We comprehend exactly what types of deformation takes place at different depths along-dip a fault interface, and no new features are observed anymore. Well, you’re quite mistaken. Not that long ago, a whole new can of worms was opened with the seismological and geodetic discovery of non-volcanic tremor, also dubbed Low-Frequency Earthquakes (LFEs), which corresponds to events known as Episodic Tremor and Slip (ETS) — this is basically the release of a certain seismic moment over a prolonged period of time instead of a single, finite rupture/earthquake (Hirose et al. 1999, Dragert et al. 2001, Obara 2002). The time period over which these occur is variable and segmented along-strike a single, continuous fault interface (Takagi et al. 2019, Rousset et al. 2019a), and are not restricted to subduction interfaces only (Rousset et al. 2019b). Such effect of along-strike locking variability is a common observation (e.g., Métois et al. 2016) and has direct consequences for the accumulation of slip deficit along-strike a subduction interface (e.g., Herman et al. 2018), i.e., an inherent effect of the presence of finite asperities.

Semantics
Lastly, let’s follow Wang and Dixon (2004) closely as they warn about the pitfalls of semantics. Different sub-fields — and I’m not just talking about geodynamics on it own — can understand the same word to mean something different. In this, Wang and Dixon (2004) use “coupling” as a common example of a term where kinematic observations are intertwined with dynamics terms of interaction. One could easily offer up other terms, such as e.g. “afterslip”, that do not have a clear-cut definition but is widely thrown around to mean ‘something that happened after a major earthquake occured’. Let’s not let all of our hard work be in vain by using terminology we either simply misuse, or overly complicate. It never hurts to explicitly explain what you mean with the terminology you use, even though it is crystal clear to you. Just a little tip.

So tell me, Curmudgeonly Commenter, did you learn anything about earthquakes? Was I clear and extensive enough for you? Happy at long last with my response? Let me know in the comments…

Yours truly,

The Sassy Scientist

PS: This series of posts was written with inspiration of the older papers, before the 60’s especially; they’re a lot of fun and meanwhile you’ll obtain some ideas to present in your undergraduate courses. In case you’re working on the earthquake cycle, from a geodynamics or rock mechanics perspective, especially but not exclusively on facets I haven’t mentioned above, I endorse/recommend/applaud mentioning it in the comment section. Or contact us for a proper guest author post! Get your word out to the public and get people interested.

References:
Dragert, H., Wang, K. and James, T.S. (2001), A silent slip event on the deeper Cascadia subduction interface. Science, 292, 1525–1528, doi:10.1126/science.1060152.
Herman, M.W., Furlong, K.P. and Govers, R. (2018), The accumulation of slip deficit in subduction zones in the absence of mechanical coupling: Implications for the behavior of megathrust earthquakes. Journal of Geophysical Research: Solid Earth, 123, 8260–8278. https://doi.org/10.1029/2018JB016336.
Hirose, H., Hirahara, K., Kimata, F., Fujii, N. and Miyazaki, S. (1999), A slow thrust slip event following the two 1996 Hyuganada earthquakes beneath the Bungo Channel, southwest Japan. Geophysical Research Letters, 26( 21), 3237–3240, doi:10.1029/1999GL010999.
Métois, M., Vigny, C. and Socquet, A. (2016), Interseismic coupling, megathrust earthquakes and seismic swarms along the Chilean Subduction Zone (38°–18°S). Pure and Applied Geophysics, 173(5), 1431–1449. https://doi.org/10.1007/s00024-016-1280-5.
Obara, K. (2002), Nonvolcanic deep tremor associated with subduction in Southwest Japan. Science, 296, No. 5573, 1679-1681.
Rousset, B. (2019a), Months-long subduction slow slip events avoid the stress shadows of seismic asperities. Journal of Geophysical Research: Solid Earth, 124. https://doi.org/10.1029/2019JB018037
Rousset, B., Bürgmann, R. and Campillo, M. (2019b), Slow slip events in the roots of the San Andreas fault. Science Advances, doi:10.1126/sciadv.aav3274
Takagi, R., Uchida, N., and Obara, K. (2.019), Along‐strike variation and migration of long‐term slow slip events in the western Nankai subduction zone, Japan. Journal of Geophysical Research: Solid Earth, 124, 3853–3880. https://doi.org/10.1029/2018JB016738.
Wang, K. and Dixon, T.H. (2004), “Coupling” semantics and science in earthquake research. Eos, Transactions of the American Geophysical Union, 108, 180, https://doi.org/10.1029/2004EO180005
Zebker, H.A., Rosen, P.A., Goldstein, R.M., Gabriel, A. and Werner C.L. (1994), On the derivation of coseismic displacement fields using differential radar interferometry—the Landers earthquake. Journal of Geophysical Research, 99:19617–34.

The Sassy Scientist – Earthquake Exoteries Nr. VI

The Sassy Scientist – Earthquake Exoteries Nr. VI

Every week, The Sassy Scientist answers a question on geodynamics, related topics, academic life, the universe or anything in between with a healthy dose of sarcasm. Do you have a question for The Sassy Scientist? Submit your question here or leave a comment below.

In a comment on a post about the key papers in geodynamics, the Curmudgeonly Commenter asked:


Could you please point out some exceptionally important papers in geodynamics and tell us something interesting about the history of the field?


Dear CC,

Over the past few weeks (it’s almost been an entire month! time flies when you’re having fun) we’ve been mainly been discussing early seismological observations and theory, rock mechanics and of course our beloved discipline: geodynamics. But — and I know this is hard to believe — there are also other disciplines looking into earthquakes. Who knew, right? This week, I’ll give them a little limelight.

Other observations: geodesy
Whereas the rock mechanics researchers were focussed on comparing their results to seismological observations, other researchers were more interested in potential surface expressions and uncovering whether any more aspects of the earthquake cycle were missing. Geodesy, can’t live without it. With the advent of GNSS data — GNSS = Global Navigation Satellite System; GPS is the American, GLONASS the Russian, Galileo the European, and (in 2020) BeiDou the Chinese system — came a wondrous richness of information of surface deformation (Ryan and Ma 1998; Bastos et al. 2010). Finally we have a fully 3D vector of surface deformation with (generally) very small error margins. This is nothing compared to the wonder of (Inferometric) Synthetic Aperture Radar — a.k.a (In)SAR — which provides high-resolution, continuous displacement fields of the surface based on the reflection of a beam sent down to the Earth’s surface from a satellite (e.g., Zebker et al. 1994; Bürgmann et al. 2000). One note should be made here; not every environment is particularly suited for every satellite that provides InSAR since the resolution and power of the satellite-sourced beams is variable. Therefore InSAR is most often used to detect the surface deformation of objects such as volcanos and areas that are arid, i.e., unvegetated, even though the newest generation of satellites can actually ‘look through’ vegetation. Since InSAR only measures the reflection of a single beam, one only obtains the deformation in that one (the so-called line-of-sight) direction: not a 3D deformation field as with GNSS. However, combining several images with different lines-of-sight introduces the possibility to resolve a complete 3D deformation field (Fialko et al. 2001; Wright et al. 2004), which can be further enhanced by the inclusion of GNSS vectors (e.g., Wang and Wright 2012). So much more data to invert for! Now we must be exactly sure that we know exactly what happens at and around the fault interface before, during, and after major earthquakes, right? …. Right? Well, we don’t. Easy conclusion, I know.

So why is it still so hard, you ask me? Well, there are some additional complexities. Come back next week if you want to find out what they are.

Yours truly,

The Sassy Scientist

PS: This post was written using only some observations. Some are still missing to foster a full picture.

References:
Bastos, L., Bos, M.S. and Fernandes, R. (2010), Deformation and Tectonics: Contribution of GPS Measurements to Plate Tectonics – Overview and Recent Developments. doi:10.1007/978-3-642-11741-1_5. In: Sciences of Geodesy - I, Chapter: 5, Publisher: Springer Berlin Heidelberg, Editors: Guochang Xu
Bürgmann, R., Rosen, P. and Fielding, E. (2000), Synthetic Aperture Radar interferometry to measure Earth’s surface topography and its deformation. Annual Reviews of Earth and Planetary Science, 28, 169–209.
Fialko, Y., Simons, M. and Agnew, D. (2001), The complete (3-D) surface displacement field in the epicentral area of the 1999 Mw 7.1 Hector Mine earthquake, California, from space geodetic observations. Geophysical Research Letters, 28(16), 3063–3066.
Ryan, J.W. and Ma, C. (1998), NASA-GSFC's geodetic VLBI program: a twenty-year retrospective. Physics and Chemistry of the Earth, 23, 9–10, 1041-1052. 
Wang, H. and Wright, T. (2012). Satellite geodetic imaging reveals internal deformation of western Tibet. Geophysical Research Letters, 39(7).
Wright, T.J., Parsons, B.E. and Lu, Z. (2004). Toward mapping surface deformation in three dimensions using InSAR. Geophysical Research Letters, 31(1).
Zebker, H.A., Rosen, P.A., Goldstein, R.M., Gabriel, A. and Werner C.L. (1994), On the derivation of coseismic displacement fields using differential radar interferometry—the Landers earthquake. Journal of Geophysical Research, 99:19617–34.