Some of these stony meteorites have already been classified.
USA150806
This stone wasn’t “Recognized” as a meteorite until 2019 August.
Now classified as “Ureilite”, and its name was approved on 2020 April 5th, as:
Hardpan Flat (URE)
My last article was at the beginning of 2020, before the start of this current pandemic. You would think that with all of this imposed isolation at home, I would have had even more time to write articles. But the opposite is what actually happened. At first, I didn’t see any of this effecting me much. But very soon after all of the universities and their laboratories shutdown, and all of the “authenticators of meteorites” went into isolation, I started getting a huge increase in the number of people contacting me, and requesting that I authenticate their “meteorite”. Unfortunately, none of their specimens were obvious meteorites (except for one, which just came in the mail, and I will discuss later). And as the economy worsened, these meteor-wrong finders became more desperate and insistent, and would pressure me by offering to pay any price to get their specimen authenticated.
Eventually, I started to turn-away some of these people and, instead, focused only on those clients that honestly and simply wanted to know, “What kind of rock is it exactly?” But even then, it was becoming obvious to me that this was taking up too much of my time. Especially, when it got in the way of me finishing my article for that month. Soon, I stopped taking on new clients, and resumed my other interests, like mushroom hunting and competing in disc-golf tournaments. I started taking trips to Arizona, and between disc-golf tournaments I would cold-hunt for new strewnfields. I did a lot of hiking in Arizona in a variety of locales, but I only found one meteorite, and it was only fragments from a find that I made the previous year.
Before I knew it, another deadline for a Bob’s Findings” article came due, and I had to make a decision. I passed on doing the article, and I committed to meteorite-recovery in Nevada. The pandemic had caused a canceling of all the disc-golf tournaments in California and Nevada, so I left my golf-discs behind (and had them sold on eBay). So, as soon as the weather warmed-up in northern Nevada, I told my remaining clients that I was going on “vacation” to Meteorite-Land. This raised some eyebrows, but my excuse was, “Think of this as extreme-social-distancing. The nearest human to me wouldn’t be 6 feet away, but 6 miles away!”
I rationalized that I was more at risk staying at home in Southern California. Luckily, my wife thought she was more at risk, if I stayed home. Win-win!
What started as a planned one week getaway turned into a three week meteorite-recovery effort.
It started off slowly. The first week went by with very little to show for my efforts, so I extended the “getaway” one more week. By the end of the second week, I had to extend it for a third week, mainly because I had underestimated the size of the strewn-field that I had stumbled into. By the time I returned home, I had tallied over 74 fragments and individual stones, probably representing 5 different falls. Documenting and tabulating all of these finds took longer than I anticipated, especially while I was catching-up on the back-log of meteor-wrong clients. I simply had to skip doing an article that month. Instead of writing an article about another couple dozen of new “orphaned USA chondrites”, I decided to dedicate 2020 to finding a way to get some of my finds classified and into the MetBull.
Long story short, I found a classifier that was willing to do Ordinary Chondrites (probably the only one in the USA). Not knowing how long that would last, I dedicated 2020 to getting classified some of those “orphaned USA chondrites” that I’ve been writing about – at least, the ones that I found. Which meant that another edition of Meteorite-Times would go by without a Bob’s Findings entry.
So now that brings us up-to-date, and probably a good opportunity to review the past year with an eye towards where to go next and what needs to be published.
Some of the meteorites on the following list will probably deserve their own, future “Bob’s Findings” article:
Hardpan Flat** – Official – 2015 – Nevada, USA – Ureilite – 2.6 grams – Meteoritical Bulletin, No. 109†, in preparation (2020).
Above is an image of Hardpan Flat (URE) before a type-specimen was cut (formerly known as, “USA150806”).
Above is an image of the thin-section used to classify Hardpan Flat (URE). And a link to a close-up of that thin-section is “HERE“.
Cleghorn Lakes ** – Official – found in 2018 – California, USA – (LL3) – 1100 grams – Meteoritical Bulletin, No. 109†, in preparation (2020).
Above is an image of one of the smaller fragments of Cleghorn Lakes (LL3) – formerly known as, “USA180513”.
Tungsten Mountain meteorites:
For the past 18+ years I’ve been recording the 700+ finds from this DCA (Dense Collection Area). I felt that, in honor of the 20th anniversary for this DCA, that we should finally determine “What actually is the classification for the majority of these finds?” (which on average is smaller than 20grams). Over this time, many dealers and collectors have been self-pairing their unclassified specimens to TM 001, which is classified as H4. But among those of us fieldworkers who have handled a large number of these small fragment, our consensus is that a very high percentage of these 700+ finds are most likely H5/6.
It was time to resolve this issue. To this end, I randomly selected specimens from a large batch that were recovered by our team prior to 2002. Obviously, these are what can be termed as, “the early finds”. And for reasons I won’t get into here, I feel it is noteworthy that these specimens selected for classification were all collected in a 1 year time-period, not to mention, they were some of the “earliest finds”.
After cutting type-specimens and making thin-sections from the eleven (11) chondrites that I had selected, I closely examined them. I was convinced that I was looking at a variety of H-chondrites, and that I was going to fail at getting a high percentage of them to be classified as H5. Which is why I was stunned when ALL of the classifications came back as: H5 S3 W3
It will be interesting to see whether “H5” will continue to be the predominant-class when batches of samples are taken for classification from more recent recovery seasons. But, in any case, dealers and collectors should discontinue self-pairing to H4, and instead, provisionally label as “probably H5 – most likely paired to TM 007”!
TM 054 H5 S3 W4 Olivine (Fa18.6±0.4, n=9), Low-Ca Pyroxene (Fs16.5±0.5Wo1.3±0.3, n=13).
TM 055 H5 S3 W4 Olivine (Fa19.0±0.8, n=15), Low-Ca Pyroxene (Fs16.5±0.7Wo1.3±0.2, n=17).
TM 056 H5 S3 W4 Olivine (Fa18.7±0.9, n=19), Low-Ca Pyroxene (Fs16.7±0.7Wo1.4±0.2, n=20).
TM 057 H5 S3 W4 Olivine (Fa18.7±0.4, n=14), Low-Ca Pyroxene (Fs16.3±0.4Wo1.3±0.2, n=13).
TM 058 H5 S3 W4 Olivine (Fa19.1±0.6, n=18), Low-Ca Pyroxene (Fs16.8±0.6Wo1.3±0.1, n=16).
TM 059 H5 S3 W4 Olivine (Fa19.0±0.7, n=20), Low-Ca Pyroxene (Fs16.9±0.9Wo1.3±0.1, n=16).
TM 060 H5 S3 W4 Olivine (Fa18.7±0.6, n=20), Low-Ca Pyroxene (Fs16.6±0.3Wo1.3±0.2, n=14).
TM 073 H5 S3 W4 Olivine (Fa19.3±0.5, n=9), Low-Ca Pyroxene (Fs16.8±0.7Wo1.2±0.2, n=20).
TM 084 H5 S3 W4 Olivine (Fa18.9±0.5, n=16), Low-Ca Pyroxene (Fs16.9±0.8Wo1.1±0.2, n=7).
TM 116 H5 S3 W4 Olivine (Fa18.8±0.5, n=13), Low-Ca Pyroxene (Fs16.6±0.6Wo1.2±0.1, n=12).
TM 121 H5 S3 W4 Olivine (Fa18.7±0.8, n=23), Low-Ca Pyroxene (Fs16.4±0.7Wo1.0±0.3, n=12).
Here is a chart of select classified TM finds – with the addition of the above “Olivine” values:
Fayalite (mol%) | Plus/minus | Petrologic Grade | Shock Stage | W. Grade | TM number |
17.5 | 0.1 | H4 | S2 | W3 | TM 003 |
17.9 | 0.1 | H4 | S2 | W3 | TM 009 |
18.2 | 0.2 | H5 | S2 | W3 | TM 010 |
18.5 | 0.2 | H5 | S3 | W3 | TM 007 |
18.6 | 0.1 | H6 | S2 | W5 | TM 004 |
19.2 | 0.2 | H6 | S2 | W5 | TM 002 |
19.3 | 0.5 | H4 | S2 | W3 | TM 001 |
20.3 | 0.3 | H5 | S3 | W2 | TM 008 |
25 | 0.2 | L6 | S4 | W3 | TM 006 |
25.5 | 0.2 | L6 | S2 | W3 | TM 005 |
This chart does a good job of showing that there is no overlap of the Fayalite values (meaning that they are very unlikely paired) for the three H4, the two H6. and the two L6 stones shown on the chart. But among the H5 there are many “overlapping Olivine values” (except for TM 008), which suggests that those stones are likely paired. Regardless of any proof of pairing, the sheer number of H5 classifications suggests that the majority of fragments found in Edwards Creek Valley are NOT H4!
Some of the “USA chondrites” that I got classified had “problematic” find locations, so they were assigned “Nova” numbers:
Nova 062 ** Official 2016 California, USA L5 1500 grams Meteoritical Bulletin, No. 109†, in preparation (2020).
Nova 063 ** Official 2016 California, USA H5 18.3 grams Meteoritical Bulletin, No. 109†, in preparation (2020).
Nova 064 ** Official 2016 California, USA H5 70.9 grams Meteoritical Bulletin, No. 109†, in preparation (2020).
Nova 065 ** Official 2016 California, USA L4 1144 grams Meteoritical Bulletin, No. 109†, in preparation (2020)
Northwest Africa (NWA) 13219 (Eucrite-cm): This highly shocked breccia consists predominantly of pyroxene and plagioclase (now partly maskelynite).
Approved 2020 April 5th. This beautifully crusted Eucrite needs to find a museum, so that it can be properly displayed… contact me.
My one Arizona find is still pending name approval:
Name | Class | Mass | Status | Comments |
---|---|---|---|---|
Bouse (b) | H4 | 2200 | Pending name approval | Found while searching for additional Bouse (L4-6) stones. |
At least, one of the samples/specimens sent to me for authentication-identification by one of my clients was actually a meteorite.
It is an obvious chondrite, and it is currently getting classified.
Magnitude 6.5 Nevada Earthquake of 2020:
The strongest Nevada earthquake in over 65 years occurred while I was there. After hiking all day and driving at night for hours, I pulled into a reststop to get some sleep in my truck. After only a couple hours, I found myself wide-awake at exactly 4AM. Understand that I never EVER – on my own – wake up at 4AM! Perplexed and miffed that I ruined my nap, I attempted to go back to sleep. But 3 minutes later, my truck started shaking. Again, I sat straight-up, while cursing and looking for who or what was shaking my truck. But there was nobody and nothing and no wind. Just a couple light-poles swaying. Being from SoCal, I just went back to sleep, and while drifting-off, I tried to remember the last time that I ever heard of a temblor in Nevada. I slept through all of the after-shocks.
The news accounts weren’t clear exactly where the epicenter and surface rupture was. I debated whether I should change my plans and instead try hunting for a fault-line. But it didn’t matter. By serendipity, I happened to drive up onto the rupture zone — which went right-thru the pavement of US95 just east of the Columbus Salt Marsh. The earthquake only occurred 30 hours earlier, but Nevada DOT had already replaced with blacktop where the pavement had wide cracks, and where it had buckled-up, they made it flush by grinding it down. The displacement didn’t occur at just one point in the road. It crossed the pavement at several places, due to the pattern of the rupture zone being “en-echelon” segments, as the seismologists say, and sub-parallel to the highway. Speaking of “seismologists” there were dozens of them fanned out all over the alluvial fan that was crossed by this “Monte Cristo” fault-line. (By the way, it’s the USGS that calls this the “Monte Cristo Range Earthquake”, but the local geologists prefer to just call this the “eastern extention of the Candelaria Fault”.) I approached a couple of the geologists/seismologists, and they were all very cordial. You could tell they were all excited, that they were in their geeky 7th Heaven, as if they were all at an earthquake convention in Las Vegas. We were all taking photos and measurements of a long crack in the ground. For links to some of these images, “click” HERE and Here.
You don’t have to be a nerd to look at a rupture crack in Recent alluvium, and have the hair rise on the back of your neck. The Earth moves! “It’s alive!”
Two weeks too late.
This next paragraph is NOT about a meteorite that I found. It’s about the one that I didn’t find. The one that “got away”. I guess, I am like the fisherman that returns home with a cooler full of fish, but he can’t stop thinking about that one big fish that came off the hook and got away. In my defense, allow me to explain.
You have to picture me hiking for miles in the heart of Nevada – in the middle of Nowhere, Nevada – in the middle of a valley that I don’t know if it has a name. There is no sign of any people in any direction for six miles. Admittedly, there were tire-tracks on the dirt road that I drove into this valley, but I reckoned they were at least two weeks old. But, as far as seeing any other tracks, in all those miles walked, there were none. There were plenty of animal tracks, but no human footprints, let alone any bicycle or dirt-bike tracks. Every once in a while, I would spot an overturned rock, which would make me wonder if somebody had moved or kicked it. But in every case, I would eventually find the tracks of the animal that knocked it over.
I preferred to hike on the “blow-outs”, which are basically swales between low sandy dunes. Many of them are covered with a lag-gravel of small pebbles of uniform-size and dark-patina. Any object (or meteorite) that was on this uniform-gravel-covered “blow-out”, that was over-sized or of a contrasting color, would stick-out like a sore thumb. Any stone that may have been kicked-up and lying on top of this pavement, would stick-out, as well. I use this term “pavement” loosely, but I did note that I did not leave a noticeable footprint on that surface. When your search pattern criss-crosses a large uniform, flat area, you are constantly looking for surface disturbances to indicate the areas that you have already searched, in order to minimize overlap. Learning this expertise is essential, if not unavoidable.
So, for me to spot (from a distance of ~25 feet) a disturbance in the gravel, (actually the one depicted in the image below), is not that surprising to me. Seriously, I’m not bragging. But, how that anomaly came to be, was soon to blow my mind.
As I got closer to this “disturbance” in the gravel, it quickly became apparent that it was a tight accumulation of pebbles and not one solid object. And as I bent down to look closer, it was now apparent that each pebble had a (clean) top-side and a bottom-side coated in lakebed clay/silt. With my brain, now, fully in cognitive dissonance, I found myself on my hands and knees looking for how and from where these pebbles came. Luckily, I found the still-fresh depressions from where the four pebbles had been plucked. (And I say “luckily”, because had it rained after these pebbles were moved, the depressions would have dissolved.) As can be seen in the image below, all four depressions are within a one-foot radius of where the pebbles were placed. And I say “placed”, instead of “piled”, because when I picked-up these four pebbles, it revealed that there was a depression.
Astonishingly, an attempt had been made to fill-in and cover that vacancy!
This “vacancy” was a still-fresh, well-preserved depression revealing that a well-rounded stone (equal in size to the volume of the four pebbles) had been plucked from that spot. And for some obvious, yet, unfathomable reason, it was important to that “person” to hide that action! And remember, I had not seen any footprints (other than my own), nor did I encounter any other afterwards, now that I was keenly looking for them. Bizarre!
But what other explanation other than this: a very experienced hunter (as well as, hiker) had found a meteorite. And anticipating a possible strewnfield, attempted to keep it secret.
Bizarre on top of bizarre, is that he FAILED, and that just two weeks later, I had already found his secret.
Beyond Bizarre, that a meteorite would fall in the middle of nowhere, and sit there forever – until a person did find it – and had that person not found it, only two weeks later, I have no doubt that I would have found it!
And if this coincidence continues, and that “finder” eventually reads this article, I say to you, “Congratulations! You earned it!”
All in all, 2020 has been an eventful year.
References:
Meteorites from Verish appearing in the MetBull the list of meteorite falls and finds submitted by Robert Verish to the Meteoritical Bulletin.
My previous Bob’s Bulletins can be found *HERE*
If you would like more information, then please contact me by email:
bolidechaser at yahoo-dot-com