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cossatoton AI for real-time fusion plasma behavior prediction and manipulation

There is a trade off between the half life and the intensity of radiation (i.e. the number of particle emissions per unit time), correct? So even if waste products are radioactive for thousand of years, they can be more easily handled than materials with a faster decay rate, even if they need to be stored for longer.

cossatoton PhD student finds lost city in Mexico jungle

The actual journal article is here (open access): https://www.cambridge.org/core/journals/antiquity/article/ru...

Based on the images, I think that the largest structure is about here: 18.891548°N, -89.323622°E. But you can't see anything in google earth (otherwise why would he have had to traverse 16 pages of google search results).

cossatoton William Cowper and the Age of the Earth [pdf] (2019)

It was assumed (correctly) by not long after Cowper's time that the strata were of different ages because of the different fossil assemblages in them, but of course no one had any data-derived numbers to put on the different eras.

Furthermore, there is abundant evidence for erosion between many of the layers in the Grand Canyon, and they don't look anything like flood deposits, which are generally chaotic (unsorted, discontinuous bedding, etc) because of the high energy in the environment during deposition. Paraconformities indicate a cessation of deposition, which is often accompanied by erosion. They are 'para' conformities not because of the gap in time between the layers, but because there wasn't major deformation of the Earth's crust during that time (this means substantial tectonic activity), which would cause regional tilting of the lower (older) rocks. Throughout much of the middle of the country, there are young sediments deposited in a paraconformable relationship on top of rocks that are 400 million years old (making up the surficial bedrock of the region), because there hasn't been major tectonic activity in the region since those 400 million year old rocks were deposited (and indeed, for close to a billion years before that in much of the midcontinent).

cossatoton Launch HN: Silurian (YC S24) – Simulate the Earth

Doyne Farmer's group at Oxford does 'agent-based' economics simulations in this vein. He has a new book called 'Making Sense of Chaos' that describes it.

cossatoton Ask HN: Where do you subscribe to published journal topics?

I don’t know if this is compatible with your use case, but as a working scientist interested in my sub field and those adjacent, I subscribe to email alerts from publishers (all nonprofit scientific societies with the exception of Nature). There are both table of contents emails and keyword-based emails. Not sure if RSS feeds are available. If you’re wanting to do some automated parsing, you might need a dedicated email address (and of course access through a university library or similar).

cossatoton The Blue Collar Jobs of Philip Glass

Much of O’Keeffe’s work relates to gender in a way that was counter to the zeitgeist of the contemporaneous southwest. Johnson more or less embodied a nascent Delta blues, defining it on wax, then died. It was too early in the codification for there be something to transcend. His career was like 9 months long. McCarthy I don’t know, can’t read because I don’t like the violence.

Nonetheless your final point is far more vapid because the frontier is where civilization is created and destroyed. It is where norms, values and modes of production of some civilization are placed with decreasing amounts of their domestic support, and usually in increasing conflict with a different civilization, so that it becomes clear what aspects have some more fundamental truth or at least robustness, and what is simply town and gown, responding to the ever shifting attentions of easily bored patrons.

cossatoton Is running a more efficient way to travel than walking?

Was your friend perhaps Muhommed Ali, fighting George Foreman in Zaire? Or perhaps Homer Simpson fighting Drederick Tatum?

cossatoton Interstellar movie black hole implemented with Einstein's equations in C++

And the infinite book case is a shout out to Borges, right?

cossatoton Japan issues first-ever alert over risk of Nankai Trough megaquake

The Nankai Trough is the name for the oceanic trench where the Philippine Sea tectonic plate subducts below the eastern margin of the Eurasian tectonic plate, where southern Japan sits. The interface between the two plates is the subduction fault line that hosts large earthquakes in southern Japan.

cossatoton Prevention of HIV

I’m sorry your family was put through so much termoil.

cossatoton Starting Hospice

Goodbye, Jake.

cossatoton Hydrothermal explosion at Yellowstone National Park

I wrote about this in a previous HN thread a few years back. Not clear that it's a great idea: https://news.ycombinator.com/item?id=28593452#28599027

cossatoton Borges on Chaos Theory

Should the apocryphal status of a single item in his list change your (or anyone else's) opinions and associations of the horrors of the Holocaust?

cossatoton Tom Waits vs. Frito-Lay, Inc (2003)

The Blind Boys of Alabama do great covers of Jesus Gonna Be Here and Way Down in the Hole, both on the Spirit of the Century album. The version of Amazing Grace set to the music of House of the Rising Sun, though, is to me the standout on an excellent album.

cossatoton M 4.8 – 2024 Whitehouse Station, New Jersey Earthquake

It's possible. Seismicity has been associated with reservoirs[1] (the most well known is probably an earthquake in Egypt following the construction of the Aswan High Dam) and even rainfall[2]. There are both potential triggers from the increase in the stress on the fault, as you state, due to the weight of the water; and (probably more important) the increase in pore fluid pressure along the fault.

It's a bit complicated, because the increase in stress on the fault from the weight of the reservoir can actually be primarily an increase in normal stress, i.e. an increase in the clamping force preventing the fault from slipping (i.e. the crust on either side of the fault sliding, i.e. the earthquake), so the weight of the reservoir can actually impede, rather than promote, seismicity. However if the geometry of the system is just right such that the increase in shear stress from the weight of the reservoir can increase on the fault, then the reservoir could really trigger the earthquake. Typically, though, the increase in pore fluid pressure is the most likely trigger as it's not geometry dependent--pumping a fracture with fluids will always promote failure. This is what happens with the seismicity associated with natural gas fracking and subsequent wastewater fluid injection.

The thing that is hard to grapple with all of this is that changes in stress and fluid pressure on the fault are really, really small compared with the ambient stress and fluid pressure. These are tiny changes, but there is good reason to believe that many faults, especially those in seismically active areas, are very close to frictional failure (i.e., slipping and producing an earthquake) all the time. So therefore little things can perturb the system. However, it's worth keeping in mind that most of these small changes slightly increase or decrease the time to failure (as the primary loading that is causing the stress on the fault is probably continually happening at very low rates), rather than being the ultimate cause of the earthquake.

[1]: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C48&q=dam...

[2]: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200...

cossatoton M 4.8 – 2024 Whitehouse Station, New Jersey Earthquake

Earthquake waves have several propagation speeds, because there are different types of waves. The fastest is called the P-wave, which is a compressional (longitudinal) wave, similar to a sound wave, with a velocity of ~5-8 km/s for typical continental bedrock. The second fastest is the S-wave, or shear wave, which is about 65% of the P-wave speed. These waves produce relatively little displacement at the surface (except for close to the epicenter of large earthquakes) but are important seismologically. Then, there are the surface waves, which are caused by the interaction of the S-waves with the surface (in a way that I don't 100% understand). These travel about 90% of the S-wave speed, but they have the biggest displacements at the surface and therefore are the main ones that you feel and that cause damage.

The surface wave displacements also get amplified in wet or loose soil, so the ground shaking and seismic damage is also much greater areas on top of sediment rather than bedrock. Areas on a river, lake or coast where the land has been extended into the water by dumping fill dirt are the worst--ground shaking is really bad and they are very prone to liquefaction.

The difference between the arrival times (at any given point on earth) of the different phases of seismic waves is a function of the distance from the earthquake itself (the hypocenter) and the observation site. It is close to linear in Euclidian distance relatively near the earthquake hypocenter, but becomes more nonlinear farther from the earthquake, because the wave speeds are faster at depth (denser rock) so the travel paths of the wave fronts (the ray paths) are nonlinear. These differences in arrival times are one of the main ways of locating the hypocenter of an earthquake given observations from seismometers at multiple sites. It's essentially triangulation, except with time differences instead of angles--this is done through solving a system of equations.

Additionally, S-waves can't pass through liquids, so there is the 'S-wave shadow zone' that occupies a large fraction of the side of the earth opposite an earthquake where there are no primary S-wave arrivals--S-waves are blocked by the liquid outer core. This is how we found out that the outer core is liquid!

cossatoton Oklahoma receives first "Made in Oklahoma" EV

We have had, for some time, the necessary technology: https://duckduckgo.com/?t=ffab&q=cow+catcher&iax=images&ia=i...

cossatoton How to scale nuclear power

The time-scale is so long that there are no geological formations that last that long

Geologist here, highly skeptical of this statement.

Most of the land area of each continent has had essentially no seismic/tectonic activity for tens to hundreds of millions of years. With sufficient burial depth (which doesn't have to be super deep, less than a kilometer certainly) there is little reason to suspect that in most areas that haven't been disturbed in 200 million years, they will be disturbed in another 200 million years. The surface of the earth has had cycles of erosion and deposition associated with climate variations (i.e. ice ages) but the effects of these aren't always that deep.

This isn't to say that the other issues aren't important--communication of dangers to future humans (or other intelligent creatures) that may not share our language, especially. However it's a social/political problem, not a geological one.

cossatoton Multifault earthquake threat for Seattle region revealed by mass tree mortality

This is the most recent review paper of Cascadian seismicity: https://www.annualreviews.org/doi/abs/10.1146/annurev-earth-.... I would start here instead of Goldfinger's work, as there is a lot of other science to consider.

cossatoton Multifault earthquake threat for Seattle region revealed by mass tree mortality

Typically the analysis is done by digging trenches across the fault and dating pieces of charcoal found in the sediment with radiocarbon. This study is rare but not unique in using cored trees, or slices of stumps if possible, and dating the event with tree ring dating (dendrochronology), which is vastly superior when it's possible (i.e. when it is demonstrable that an earthquake kills trees). In both cases you want as much as you can get--ideally 5-10 ages at a minimum I think?

cossatoton Multifault earthquake threat for Seattle region revealed by mass tree mortality

Portland is probably similarly affected by the subduction zone, but the inland fault system is not as active as in Seattle. Nonetheless, there is a fault that is underneath the Portland Hills that could do some damage to the city.

The seismic risk faced by a city or an individual is really the product of the hazard (formally, the probability of a certain level of ground shaking) and the response of the building stock or other infrastructure. Fortunately, both cities have a large amount of wood-framed housing, which performs quite well in earthquakes (as do modern apartment buildings). However there are a lot of old masonry buildings used for schools, offices, etc. If these aren't properly reinforced, they can be deadly, not only because they are fragile but because they are heavy when they do collapse. But if you live in and work in a modern structure or an old wooden one, you'll probably make it through alright, as long as you have some food and water at home.

The big concern in both cities is actually liquefaction, where some water-saturated soils lose their strength during an earthquake. In both cities, there is some amount of housing stock built on liquefiable soils, but there is a huge amount of commercial and industrial building stock built out on fill dirt on the respective waterfronts (which is where the old masonry buildings are as well). One of the scariests scenarios is the Critical Energy Infrastructure in NW Portland, where massive amounts of oil are in the huge tanks built on fill into the Willamette, liquefying and then spilling into the Willamette/Columbia: https://www.multco.us/sustainability/cei-hub-seismic-risk-an...

cossatoton Multifault earthquake threat for Seattle region revealed by mass tree mortality

I wasn't involved in this study, but I wrote the study that estimated the magnitude of this earthquake[0]. In case anyone is interested, usually the magnitudes of 'paleoearthquakes' (historic/prehistoric earthquakes discovered by finding evidence of old ground deformation) are estimated by relating the measured offset of the earth's surface or a rock/dirt layer across the fault line to the earthquake magnitude through empirical 'scaling relationships'; larger offsets are of course indicative of larger earthquakes. These are simply functions relating a measurable attribute of the earthquake to its magnitude. In the study I did, we combined the measurements of the offsets of a number of paleoearthquakes with estimates of the map length of the fault lines involved and used length-magnitude scaling relations to further refine the final magnitudes. There are some corrections for sampling bias that are included in there and it's all nice and Bayesian if anyone wants to nerd out on the stats.

When we did the study, it was speculated that two of the paleoearthquakes, one on the Seattle Fault and one on another fault on the Olympic Peninsula, could have actually occurred in a single event, but there wasn't much evidence to support this; we consider the magnitude of it on a paragraph at the top of page 1149 but not in the rest of the paper. The recent study (TFA) makes it highly likely that they were part of the same earthquake, but they could be separate earthquakes spaced a few minutes to a few months in time (think of the 7.8 and 7.7 earthquakes in Turkiye this spring, separated by a few hours).

A bit of context about the earthquakes in the Seattle region as well as Cascadia and other areas:

- The earthquakes in the Puget Lowlands and vicinity are relatively infrequent; there are about 15 known earthquakes over the past 17,000 years, and many of them are relatively small (M 6-7). However, they are spatiotemporally clustered[1]: There was a big cluster about 900 AD, and things have been mostly quiescent since then. It can be also shown from the geologic data that at the measurement sites ('paleoseismic trenches'), there haven't been any earthquakes since 17,000 years ago (when the Puget ice sheet retreated) on many of the faults, although the Seattle fault has had a number of earthquakes before.

- The big Cascadia subduction zone events are more frequent (perhaps every 500 years?) and larger, but they may not all be M 9 events, unlike what has been discussed in the famous New Yorker article. That article is based largely on the research of Chris Goldfinger, a scientist at Oregon State University, whose views are credible but on the high side of credible, in the eyes of many other scientists in the region. Many of the earthquakes suggested by the geologic data could be smaller earthquakes (M 7.5-8.5) which won't cause as much ground shaking over such a wide region.

- Earthquakes cause seismic waves at the fault surface, and these attenuate as they travel through the earth towards the surface. The initial magnitude of the waves as the earthquake occurs can be different for subduction zone earthquakes than for shallow earthquakes in the crust, and the attenuation is different for these as well. But importantly, not only are subduction zone earthquakes far off shore, but much of the seismic energy is released deeper in the earth as well, which means more attenuation of ground shaking by the time the waves make it to Seattle.

- A Cascadia earthquake will cause widespread but perhaps moderate damage across the PNW with perhaps, but a strong Seattle fault earthquake will absolutely destroy central Seattle, particularly Pioneer Square and Sodo. The fault comes ashore at Alki Point, for reference. However areas farther away (Edmonds, Tacoma, etc.) will not see nearly as much damage.

- SF and LA both have higher seismic hazard than Seattle[2], considering all earthquake sources, the frequency and magnitudes of earthquakes from the sources, and the seismic ground motions emanating from all of these earthquakes to a site within any of the cities, according to the most recent USGS national seismic hazard model. (See Figure 12 for hazard curves for major US cities).

[0]: https://rocksandwater.net/pdfs/styron_sherrod_bssa_puget_eq_...

[1]: https://pubs.geoscienceworld.org/gsa/geosphere/article/10/4/...

[2]: https://journals.sagepub.com/doi/10.1177/8755293019878199

cossatoton The Federal Helium reserve is for sale

The Menlo Park property is the former US Geological Survey campus, which has been moved to the NASA Ames campus in Mountain View because the USGS couldn't make rent to the GSA. It's a nice campus although some of the buildings could use some superficial renovation. It's got a lot of lab space.

cossatoton New ancient ape from Türkiye challenges the story of human origins

Yes: https://en.wikipedia.org/wiki/Name_of_Turkey

cossatoton Symmetry in Chaos

Does anyone know where to find some code examples in which RGB images are generated from the equations? I don't really understand how the mathematical solution is translated into a raster/pixel image and what the colors correspond to. But I would love to start making playing with these.

cossatoton The Oregon Resilience Plan (2013) [pdf]

Earthquake-induced landsliding is common enough that neither 90 or 14 may be open after an M 9 event, especially during the rainy season.

cossatoton The Future of the Vim Project

Personally, I do heavy coding and writing in Neovim (with more extensive config, like LSP and Copilot), but I use macvim and gvim (depending on which OS I'm using) for quick edits or file viewing, because I often need to open files from Finder or Nautilus and I don't have a terminal open in that directory.

cossatoton Ask HN: What's the coolest physical thing you've made?

The Cape Falcon plans are far more detailed so there is a lot less figuring out stuff by yourself, relative to getting written plans. It's definitely a much more efficient process and there is probably a lot less variance in the result. I winged it on my Aleutian kayak a lot with mixed results (I gave it a lot of rocker and some other whitewater-inspired geometry). Of the kayaks, I prefer the Aleutian skin on frame although it was quite painful before I got the seat dialed in, and sometimes I can't roll it very well (I'm an expert whitewater boater and have a very solid roll), and its top speed is low. But it is very light, maneuverable, quiet (waves hitting it don't make much sound) and the peaked deck sheds water so it doesn't spray your face when you are punching through waves in the surf. The F1 is probably best of both worlds.

The Cape Falcon canoe that I built deviates a bit from the design pattern because I wanted a wide and flat bottom with harder edges, similar to a lot of modern Royalex tandem canoes. It's a 16' tandem I think, and even though it is pretty wide, it is still less stable than most canoes. However it is fast and extremely maneuverable in Class III.

Skin on frame is also awesome because when you are loading or unloading a 17' boat in a crowded beach parking lot and smack the bow into the car next to yours, it doesn't do any damage to either car or boat, or so I hear.

Stitch and glue is straightforward but the woodworking part goes fast and then it's just a ton of fiberglass work, i.e. cycles of epoxy and sanding, which is not that enjoyable for its own sake. On the other hand, one of the great parts of skin on frame construction is that other than a short amount of time ripping the ribs on a table saw, the rest is basically quiet and without harsh chemicals, so you don't need earmuffs or a respirator and can listen to music and have a snack/drink.

Stitch and glue will last forever if you protect it from UV, however skin on frame will most likely need to be reskinned in 5-10 years or so.

cossatoton Ask HN: What's the coolest physical thing you've made?

You guessed it, boats. I have built a stitch and glue (plywood) sea kayak[0], an Aleutian-style skin-on-frame sea kayak[1], and a skin-on-frame canoe[2]. All were fairly approachable and straightforward projects (I built the first two with basically some hand tools, a drill and a jig saw, on my deck, but a table saw is highly recommended for skin on frame). Tons of fun and the feeling of being a couple miles offshore or cruising down rapids in a boat you built yourself is awesome.

[0]: https://clcboats.com/shop/boats/kayak-kits/petrel/stitch-and...

[1]: https://www.amazon.com/Aleutian-Kayak-Construction-Tradition...

[2]: https://www.capefalconkayaks.com/canoes.html

cossatoton Geography of Kansas (2022)

True story: I was in a bar in Lawrence with a friend late one night, being chatted up by a student of mine. When we asked her where she was from, she said some town in extreme NW Kansas (Bird City maybe? Atwood?).

"I've been there!" my friend said.

"No you haven't." my student said.

"Yes, we went there on a geology field trip last summer. That morning as we left the campsite, the back door of one of the vans was open and and a food cooler fell out. We needed food so we stopped for lunch at a restaurant when we went through that town. The restaurant wouldn't serve us because they said that they only buy enough food for the regulars, because no one else ever comes in."

The girl was quiet for a bit, and said "My mom wrote about that in a letter."