My Wonder List

There are things that puzzle GG and this is a partial list that will be updated from time to time.

  • When did the High Plains become high?
  • Why did the High Plains become high?
  • What exactly did happen in the Mojave Desert c. 75 Ma?
  • Why did the Sierra Nevada arc shut down?
  • Related, why did it shut down from north to south?
  • If the northern Sierra only went up prior to the Eocene, why are modern rivers cutting well below those deposits?
  • If the northern Sierra have gone up significantly since the early Miocene, why do climate proxies disagree?
  • If the northern Sierra only went up prior to the Eocene, then how did one form of support (crustal root?) get replaced by another (buoyant mantle)?
  • What caused the Ancestral Rockies to rise up where they did?
  • Why did the large thrust on the south side of the Uncompahgre Plateau fail to reactivate in the Laramide?
  • How much of the Laramide foreland (basement-cored) uplifts reflect some different source of stress and how much do they reflect stresses from the Sevier belt driving shortening?
  • It seems likely there was serious slip partitioning in the Sevier; where is it?
  • There are some LANFs that seem to have really formed in the brittle crust at low angles. How?

Mountains that Remade America

Jones_comp proof

For those who come hoping to see material related to the Grumpy Geophysicist’s trade book on the Sierra Nevada, The Mountains that Remade America, here are a few quick pointers. The paperback version came out in February 2020.

Read More…

Risk and Sensibility

The Denver Post ran an opinion piece posing a useful question: how did we do in evaluating risk of COVID-19? Answers are all over the map, but so many are so breathtakingly stupid as to make the value of the piece pretty minimal (“Hey, the mortality rate was only 1.4%, so not so bad!” “My restaurant didn’t have a case, so restaurants were safe!”). The tone of the op-ed leans towards “hey, we panicked, this wasn’t such a big threat after all.” Having the cojones to put that in print after over half a million Americans perished in under a year–easily the number three cause of death in 2020, and when you toss in the excess mortality since the start of the pandemic, you are up to ~650,000 deaths either directly or indirectly caused by the pandemic. The age-adjusted death rate increased by nearly 16% in 2020. COVID-19 was the number three killer in the U.S. Sure, your odds of dying if you were between 25 and 34 only increased by about 4%, making COVID about the #6 killer in that age range, but for 44-55 year olds, the odds of dying went up by 11% or so, making COVID the number 4 killer and close enough to “unintentional injury” that it could well be #3. And then none of this considers the long term impacts of having had COVID-19–of the more than two million Americans who have spent time in the hospital, something like a half million or more are seeing long-term effects from COVID-19, effects that are often pretty debilitating.

A way of looking at this is years of life lost to the disease–in essence, if you die at 25 and were expected to live to 85, that is 60 years lost, but if you die at 80 it is only 5 years lost. A paper in Nature tackles this and makes comparisons with traffic deaths, seasonal influenza, and heart disease. In the U.S., COVID-19 has been seven times the losses from influenza, about 2.3 times the loss due to transport (mainly auto accidents) and maybe about 0.4 times the loss due to heart disease. This is with a pretty conservative estimate of COVID’s impacts, and it is worth keeping in mind that we tried very hard to limit COVID-19 but not so much many of these other causes of death. Additionally, this study found that about 20% of the loss of years of life in the U.S. was suffered by those under 55.

So were we overreacting to a disease that did cause more loss of life that auto accidents (by more than a factor of two)? Certainly had we done nothing the toll would have been far, far worse (millions dead), so the question maybe should be, what were the really effective steps, and what was theater that did little? in other words, a better question is, how well did we do in balancing the risks posed by different activities for dying of COVID-19?

Read More…

A Hidden Structural Bias

Many discussions are swirling about in an effort to try to right the wrongs of centuries of oppression of people of color in America. The ivory tower is no exception, and faculty and students are trying to find ways to support students of color to come and be a part of the university.

But what if one of the biggest obstacles is the university’s business model? Here at CU Boulder, this seems to be a significant problem.

Read More…

Ever Shrinking Wilderness

OK, one of GG’s favorite sports is spotting the New York Times engaging in “wow, stuff in the west is different” writing that often contains generalities or mislocations that reflect the general ignorance of the paper’s staff with the west (like here and here). A new article is sort of along these lines; it recounts the pressures on search-and-rescue teams in the west due to naive, ignorant, or bullheaded urbanites & suburbanites escaping all the rules of pandemic America for the freedom of the wilderness. Except, unsurprisingly, that many of them have no idea what going into the wilderness entails.

So what makes the story worthy of commentary? Well, first off, this is not remotely a new trend. From the moment cell service extended into any wild area, people have been calling for help, many of them demonstrating their ignorance. GG has brought this up a few times (like here and here and here). Search and rescue teams in Boulder are pretty much out at least once a week and often daily doing everything from getting an untrained climber down off a local flatiron to searching for somebody who wandered into the wilderness on a whim to rescuing fallen and injured climbers. Even more remote areas like around Silverton in southwest Colorado get to deal with the occasional dimwit driving their SUV across the tundra to the edge of a cliff where they get stuck (for some reason, these are usually Texans). This is common enough that GG has run into search and rescue folks while out recreating on his own. Rocky Mountain National Park, being very popular with people from flat places, is practically a training ground for search and rescue; the level of ignorance of some visitors can be breathtaking (for instance, the family that decided to cut down a tree in their illegal campsite by a very popular lake IN A NATIONAL PARK). Is it worse in the pandemic? Well, gosh, yes. Maybe this all looks new to folks in Pinedale, Wyoming, where the focus of the Times’s story is, but it surely isn’t to folks in the Sierra Nevada or most of Colorado.

So this story follows in the footsteps of so many in making something that has been going on for a long time into something dramatically changed; how much of that exaggeration is ignorance of the reporter or a calculated decision to reflect the likely views of the readers is unclear. The other thing it does is make it sound like the Wind Rivers are Xanadu or some lost continent only now being discovered–which may well be true for New York Times reporters and readers, but isn’t for millions of folks in the West. From reading this, you’d think this was the most isolated spot possible and no it is gone–GONE, I tell you! Um, well, compared to nearby Grand Teton National Park and Yellowstone National Park (both places where the search and rescue teams keep busy), yeah, the Winds are less hammered, but they are far from the last place some quotes would have you believe (GG can think of a half dozen places far less known, far less visited than the Winds, and he bets most westerners can do the same).

Now to be fair, the article does point out a big problem: search and rescue is a volunteer job. But then, too, in much of the rural west, so is firefighting (wonder if the Times will discover that soon); some of GG’s colleagues are volunteer firefighters. And if it was just locals being rescued–folks who knew their way around and had the bad luck to break a bone, get struck by lightning or get stuck behind a suddenly swollen stream–volunteers would be enough. But the influx of the woefully unprepared–and this story has a nice selection to choose from–has already stressed more popular parts of the West. Will some places decide to dedicate some of their motel taxes to rescuing visitors? It does seem like this might be a good idea. But is this purely a new thing brought on by COVD-19? Well, no.

Depressurizing Geobarometry

Five years ago GG pointed to a paper threatening the cherished assumption in petrology that the pressure recorded by minerals is equal to the overburden pressure. GG has never been comfortable with that assumption, and missed (until now) a paper that is far more comprehensive in its impact. And frankly, it is so blazingly obvious that GG is embarrassed that this has been under the radar for so long. The paper is Yamato, P., and Brun, J.P., 2017, Metamorphic record of catastrophic pressure drops in subduction zones: Nature Geoscience, v. 10, p. 46–50, doi: 10.1038/ngeo2852. The killer money figure is this:

All the dots in the top panel are peak pressures reported in the literature versus the subsequent nearly isothermal pressure drop also reported, where the circled points actually have that second pressure separately measured. The first thing is that this linear array makes no sense: it would almost require that rocks go down on a spring: the farther down they go, the more rapidly they bounce back up. You’d think some rocks would just stay down there and heat up and that the subsequent rise could well be independent of the journey down. The second part is that this linear array makes perfect sense if you are looking at the difference between the pressure when the rocks are on horizontal compression versus horizontal extension, which is what the bottom panel is illustrating. In essence, if the vertical normal stress is constant (σv), then at failure in compression it would be σ3 but in extension σ1. With pressure being an average of the stresses, you then get a massive pressure drop, greater if the rock is in the brittle regime (∆PFRIC) than the ductile regime (∆PDUC). The authors estimate these curves as shown by the solid lines in the top panel and it sure seems like the simplest explanation for these massive decompression events is simply that the stress field changed.

How this changes a tectonic interpretation of the geobarometry is illustrated in their Figure 4:

The black line in the lefthand graph is what has typically been interpreted to date; in the righthand graph they correct for compressional and extensional stresses. Instead of a rock blasting its way to the surface and then stopping, in the right hand panel the rock goes down and then comes back up with the vertical axis now being the lithostatic pressure.

Now this isn’t without a pile of caveats and potential flaws. First, at these depths there is no reason for the principal normal stresses to be aligned with the Earth’s surface, so this is a worst case scenario. Second, it is a bit of a surprise that the points going all the way to over 4 GPa, seem to be in the brittle field. GG suspects that many of these rocks exhibit ductile features that would seem to contradict the inference of being in the brittle field. Third, a change in the stress field of this magnitude is pretty daunting and poses a challenge to the geodynamics community: how can stresses change that much? But if the rocks are sitting at roughly the same depth and temperature for a significant time, this might not be anything like the problem of near isothermal decompression, which does have some severe time constraints. But regardless of the challenges, frankly this makes way more sense than rocks just springing back up to some level and sitting there.

There is a follow-up paper that more fully develops some formalisms for investigating this effect in general: Bauville, A., and Yamato, P., 2021, Pressure-to-Depth Conversion Models for Metamorphic Rocks: Derivation and Applications: Geochemistry, Geophysics, Geosystems, v. 22, article e2020GC009280, doi: 10.1029/2020GC009280.

Now this paper dealt with high pressure-low temperature rocks typically associated with subduction zones, and this strongly suggests that inferences of continental rocks going to 100 km depths are mistaken. But there are a whole bunch of rather similar looking curves that are not quite as dramatic but similarly difficult to understand without this mechanism. GG is referring to the widespread evidence for massive decompression of lower crustal rocks seen the Sevier hinterland of Nevada, Utah and southeastern California. (For instance, can work outward from the overview of Hodges and Walker, GSA Bull., 1992). This has long been a major mystery as shallow level extensional structures are largely missing. Many workers have noted that Miocene and younger Basin and Range extension has led to very deep basins being created, but equivalent Cretaceous and early Tertiary sedimentary piles are rare.

This brings us to a second paper that considers this problem in the metamorphic rocks of eastern Nevada: Zuza, A.V., Thorman, C.H., Henry, C.D., Levy, D.A., Dee, S., Long, S.P., Sandberg, C.A., and Soignard, E., 2020, Pulsed Mesozoic Deformation in the Cordilleran Hinterland and Evolution of the Nevadaplano: Insights from the Pequop Mountains, NE Nevada: Lithosphere, v. 2020, Article ID 8850336, doi: 10.2113/2020/8850336. On the basis of geologic mapping and new geochronological data, these workers conclude that both Cretaceous thickening and decompression are less significant in this area, possibly indicating that the geobarometry in the nearby Ruby and East Humboldt mountains has been affected by overpressure issues like that considered above. And when you toss in structural evidence in other core complexes for changes between shortening and extension (e.g., Wells, M.L., Hoisch, T.D., Cruz-Uribe, A.M., and Vervoort, J.D., 2012, Geodynamics of synconvergent extension and tectonic mode switching: Constraints from the Sevier-Laramide orogen: Tectonics, v. 31, TC1002, doi: 10.1029/2011TC002913) it seems that much of the geobarometry in the western U.S. is due for reexamination.

Overall, this feels like a liberation of sorts. The decompression problems had produced some imaginative solutions that might no longer be necessary (e.g., Wernicke, B.P., and Getty, S.R., 1997, Intracrustal subduction and gravity currents in the deep crust: Sm-Nd, Ar-Ar, and thermobarometric constraints from the Skagit Gneiss Complex, Washington: Geological Society of America Bulletin, v. 109, p. 1149–1166.). The next few years might see wholesale revision of what was going on in the Sevier hinterland.

Shoot the Messenger?

One of the peculiarities of American politics is the disconnect between views on specific policies and how people vote. For a long time, Obamacare polled lower than the Affordable Care Act, despite the two being one and the same. While political scientists will point to how much political identification has become a core part of folks’ personalities, GG suspects there is a bit more at play. Namely that the Democrats are perversely capable of taking popular policies and then applying a label that causes a knee-jerk reaction against that policy.

Take gun laws, which most Americans think should be tightened, with increased background checks being at the top of the list, but even banning the sale of semi-automatic weapons earns majority approval. So then Beto O’Rourke comes along and boldly says “Hell, yes, we’re going to take your AR-15, your AK-47”. Which, you know, doesn’t poll quite as well, and which are pretty clearly fighting words. The net result? In part, it helped end Beto’s longshot Presidential campaign, but it did ignite another, more successful campaign, that of Lauren Boebert, whose appearance at a O’Rourke rally to tell him that he was not going to take her guns helped put her in Congress.

Read More…

Are PhDs Too Cheap?

GG suspects some of you might have gotten a PhD and thought back to days of eating ramen for the four to eight years and felt like, too cheap? Hah! But as many public universities are being pushed more and more to get their income mainly from tuition, light might be cast on the doctoral programs as sources of savings.

Here’s the simple deal: classes taken in order to get a PhD are typically small and virtually always taught by faculty and not instructors or TAs, yet the preparation for the instructor is unlikely to be less than for a lower division class (indeed, as these advanced classes are closer to the cutting edge in a field, preparation can be harder). So having faculty teaching classes with, say 5 or 10 students versus 50 or 200 is a financial loser. On top of that, a graduate student conducting research will be counseled by an advisor who will also be tenure-track faculty. It doesn’t take a lot of math to see that this is a losing proposition.

So why are there so many places to get a PhD? And why might this come crashing down in the near future?

Read More…

Post-COVID College

There have been a number of essays on what is changing permanently in academia. Many advocates of things like MOOCs and remote learning are claiming that their day has come and traditional college life is a thing of the past. Many parents and students would argue the opposite: that Zoom classrooms are a disaster, and that the money they are paying for “the college experience” is not giving sufficient payback. While these are actually two different facets of college (the first delivery of an education, the second a more complex collection of education with peer interactions, social development and personal redefinition), they overlap enough to suggest that we really don’t know what the future holds. So GG, being grumpy enough to be willing to weigh in, offers these bon mots.

First off, it is immensely transparent that the in-person university will continue to be the standard for traditional (post-high school) students. The demand is strong and the social isolation of Remote U deeply unpleasant. Universities will be wanting their faculty there in the classroom to make that experience as compelling as possible. While there might be a few upper division courses taught with some of this technology (e.g., roping in important colleagues for a special lecture) and some aspects of classroom work may well change (homework returned on paper might well end with greater familiarity with tools permitting the submission of electronic versions of work), crowded lecture halls with a human at the front of the room are nearly certain to remain.

It might be a different story at other levels of the college.

Read More…

The Coming Publication Apocalypse

To be clear, we are talking scientific publication. And to save some of you time, there isn’t a lot new here, but the trends are looking to collide sooner rather than later.

What does GG mean by a publication apocalypse? Basically the end of any meaningful evaluation of publications; we are heading rather rapidly into a blizzard of material with no vetting or meaningful review. While there are those who think this will be the most democratic way to distribute science, GG would rather point them to how equally unmoderated blizzards of material have led to minor problems in the political sphere like, oh, insurrection based largely on falsehoods.

What are the trends that are facing the whole concept of journals?

  • open access upon publication
  • high levels of publication for tenure, promotion and funding
  • preprint servers
  • junk journals
  • reviewer fatigue
  • expansion of research into more of academia

Several of these interact in poisonous ways. The perception that faculty must publish more and more frequently to satisfy promotion and tenure committees or funding agencies leads to lots of manuscripts circulating around, all of which need to be reviewed, thus leading to reviewer fatigue. Open access demands on journals are probably putting journals fully into the realm of vanity publishers: their only source of income will be what authors pay. This in turn restricts the support journals can provide to editors and reviewers. Researchers who aren’t flush with funds (for instance, many summer intern programs or honors thesis writers or advanced degree recipients who were supported on teaching assistantships) will be forced to either limit their findings to preprint servers lacking any review or junk journals that claim peer review despite lacking it. The increasing pressure on traditional journal publishers will slow the path to publication, making those junk journals more attractive.

Read More…

Depeopling Peaks?

Probably one of the oddities of the western U.S. is the way that peaks acquired their names. While in the east some Native names survived and others were named by American locals for a shape or some local dignitary, in the west an awful lot of the names were thrown on by government surveyors. Some of these names are now insulting, some were borderline obscene at the time, and some record some pretty minor events (Disaster Peak in the Sierra is not where the Donner Party met a gruesome end, nor is it the site of a massacre. It is where a surveyor’s legs were smashed by a dislodged boulder). A fair number of those survey parties were staffed by scientists, so there are a lot of names of scientists out there–including no small numbers of members of the survey parties.

This is troublesome on many levels. Most of these people had no connection to these landscapes at all. And sometimes their connection hasn’t survived the test of time well: Mt. Evans memorializes a territorial governor of Colorado who now is best known for being associated with the Sand Creek Massacre. A proposal is out to rename the peak to Mt. Blue Sky. Other names have been proposed, and Colorado’s governor has acted to create an advisory board to consider a whole host of names across the state.

While the initial focus will be on names that insult people and names of individuals who are no longer viewed in a positive way, there are a lot of other peak names out there with names of scientists. Should these survive?

Read More…