Geology Question

[ski3pin]

We recently returned from a trip to Death Valley National Park. Up one interesting canyon I found these holes bored into the rock.

You will notice the rock also broke off along this drill line. To put this into perspective, here is the setting. The drill lines are in the bottom left.

My thoughts, this is from water dripping from a now gone overhang above. A friend believes this must be man made because of the even spacing.

Thoughts on this and other ideas to consider?

 

[Wandering Sagebrush]

My two cents worth... Drilled. Spacing and diameter looks consistent.

 

[Tuff Guy 62]

Appears to be anthropogenic in origin rather than a naturally occurring phenomena.

Formation lithology and age would be useful in trying to solve the mystery.

Rocks appear to be sedimentary or tuffaceous. Is this unit known to be fossil bearing?

Maybe someone found something embedded in the rock. Rather than trying to extract risking damage to the specimen, they decided to break off the whole slab and take it with them.

 

[Casa Escarlata Robles Too]

Space Aliens!
Frank

 

[PaulT]

Jurassic laser perforated dinosaur toilet paper?

Paul

 

[Shadyapex]

They sure look man made to me. What canyon was this in? I'd love to go check it out.

 

[ski3pin]

Appears to be anthropogenic in origin rather than a naturally occurring phenomena.

Formation lithology and age would be useful in trying to solve the mystery.

Rocks appear to be sedimentary or tuffaceous. Is this unit known to be fossil bearing?

Maybe someone found something embedded in the rock. Rather than trying to extract risking damage to the specimen, they decided to break off the whole slab and take it with them.

to my amateur eye it looks like volcanic tuff.

there is extensive layering in the formation.

we saw no evidence of fossils and, although petrogylphs are nearby, there was no evidence of any in this area.

Thanks for your help in replying.

 

[Foy]

Looks man-made to me. Diameter, spacing, and depth are too uniform to be natural. I agree that somebody found a fossil or specimen of some sort and hijacked an entire slab in order to prevent messing it up. If this was in DVNP, and unless the sample was sanctioned in some fashion, the driller broke the law.

Foy

 

[Tuff Guy 62]

to my amateur eye it looks like volcanic tuff.

there is extensive layering in the formation.

we saw no evidence of fossils and, although petrogylphs are nearby, there was no evidence of any in this area.

Thanks for your help in replying.

Based on your last photos the earth materials most closely resemble rocks of volcanoclastic or possibly lacustrine origin.

Me thinks there may be paleo-poachers about.

 

[ski3pin]

<snip>
Me thinks there may be paleo-poachers about.

Quite possibly, although a bit of a haul out of here.

Thanks all for your interest and input.

 

[Lighthawk]

A good puzzler. DV seems to have more then it's fair share of unusual finds.
I tend to agree with the obvious spacing and diameters, pointing to manual extraction.
As you said, a good haul, but then again, those miners faced incredible hardships and did the impossible.

 

[Foy]

I'd say more likely specimen related than mining related. A surface adjacent to the holes in the close-up appears to have some inclusions of some sort--breccia fragments? Conglomerate pebbles? Vesicles filled with secondary minerals? Any or all could appear in a tuff or water-laid tuff.

Foy

 

[Smokecreek1]

I'm conflicted with this one Ski-like most here, it think that it';s mining related or was done some mad vandal out for so type of goody from the cliff face because that's how they drill things out. I've seen lot's of similar "holes" in similar formations because we have allot of similar geological formations up here in the high desert, and they usually are related to mining activities. However, what Foy suggests about a possible natural cause-about vesicles filled with secondary minerals or air at one time,too makes sense because I've seen the reverse indentations from these types of impressions left on both the fragment that was removed or fell from cliff face and the parent formation itself.

Had a bunch of fun up here years ago with something similar, when some hiker came in and reported "dinosaur" foot prints in some rocks-sure looked like you would think they would-yep, took U of Nevada a while to say "no", seems our foot prints had four toes , and dinosaur had three toes or was it visa versa? Anyway the tracks were formed when the parent rock broke off where there was a series of vesicles had formed in the lava. Sure looked good thou !

Smoke

 

[Foy]

Smoke, I've no doubts that the holes were drilled by some individual(s) seeking to remove a chunk of outcrop. I simply speculate they were removing a non-mining type rock or mineral specimen as opposed to a mining-type sample or specimen. The natural dimples near the drilled holes in the close-up look like some sort of primary or secondary inclusions in an otherwise barren tuff or tuffaceous shale, and may represent enough of a "pretty rock" look for someone to have gone to the trouble to remove and haul off a big chunk of it.

Mineral exploration, at least since the establishment of large swaths of protected areas, focuses on two items with equal intensity: 1) go look where the rocks are right for concentration of economic minerals, and 2) look only where those rocks lie within areas where mining is possible. Example: we have some decent gold deposits in the East and some have been mined in recent years and at present. Some of the large low grade deposits will likely never be mined due to proximity to protected wetlands. The largest high-grade uranium deposit in the country is just outside of Danville, VA. It will likely never be mined. We have oil shale and natural gas within Triassic basins which will likely never be developed due to being surrounded by various towns, cities, state parks, etc. This is not an editorial suggesting there's anything wrong with policies precluding mining in sensitive areas, instead it's just examples of why modern mining companies aren't likely to spend time and $$ pulling samples from areas where the ultimate goal--extraction of mineral commodities at a profit, is not possible due to other overriding issues concerning land use.

My last 2 years in mineral exploration were under the employ of a South African diamond mining company which came to the US and Canada primarily because of the stable political environment as compared to South Africa in the late 1970s. Diamonds occur worldwide, so they figured they might as well try to find some where they could perhaps rely on some stability as to national governments.

Foy

 

[ski3pin]

I've been doing more homework on the geology up here. I have found the white rock was deposited in extensive ash falls 11 million years ago. This tuff is named pozzolan after Pozzuoli, Italy where it is quarried. The deposit also contains zeolites and traces of mercury. Pozzolan is used in manufacturing hydraulic cement. Zeolites are used in softening water. At one time there was a small prospect up this canyon to try and profit from this uncommon resource. The effort was short lived. Quite possibly these drill marks are evidence of that effort.

 

[ntsqd]

Sounds like some were speculating sort of the reverse of these?



Recall the stealing of some of the Bishop area petroglyphs. Not likely as much of a hike out, but large and difficult slabs to maneuver around.