Central Oregon cliff scree- what are the rocks?

[doublebluff]

I have traveled to Wildhorse lake in the Steens Mountains twice over the past couple years- it is truly wonderful. A brutal hike for someone who lives at sea level...


The cliffs on the right edge of the lake are made of this kind of rock. The crystals are fascinating. This shows the crystals on edge...


This shows a couple of them on their lateral face. The embedded crystals are about the size of a half-dollar or a little bigger. I wonder if this is enough definition to have you folks help me figure out what kind of rock this is.

I lugged a couple softball-sized chunks out to put in the garden, and a few smaller ones that I might put in the tumbler. It might be kinda soft.

It is a beautiful hike, but very strenuous and at altitude. 

Any thoughts on what the rocks are and how they might have formed? Volcanic, for sure... I think.

[hummingbirdstones]

I have no clue, but it sure is interesting.

[rockpickerforever]

Aug 10, 2022 22:04:54 GMT -5 doublebluff said:

I have traveled to Wildhorse lake in the Steens Mountains twice over the past couple years- it is truly wonderful. A brutal hike for someone who lives at sea level...


The cliffs on the right edge of the lake are made of this kind of rock. The crystals are fascinating. This shows the crystals on edge...


This shows a couple of them on their lateral face. The embedded crystals are about the size of a half-dollar or a little bigger. I wonder if this is enough definition to have you folks help me figure out what kind of rock this is.

I lugged a couple softball-sized chunks out to put in the garden, and a few smaller ones that I might put in the tumbler. It might be kinda soft.

It is a beautiful hike, but very strenuous and at altitude. 

Any thoughts on what the rocks are and how they might have formed? Volcanic, for sure... I think.

Using your favorite search engine, search for "geology of Steen Mountain."  You will learn that "The mountain is formed from a large fault block of basalt that has been uplifted and tilted to the west. The fault block is part of the Basin and Range Province and the basalt is part of the Columbia River Basalt Province."

Taking it further, here's a link to more info:  THE GEOMORPHOLOGY AND VOLCANIC SEQUENCE OF STEENS MOUNTAIN IN SOUTHEASTERN OREGON

With the internet at your fingertips, The World is Your Oyster!

[vegasjames]

The long thin crystals look like plagioclase crystals.

[amygdule]

I miss traveling through SE Oregon
Thanks for posting the pictures

A quick look at a map shows that area is known as the Steens Basalt

Here's a link to a map of the area

Geologic map of the Wildhorse Lake quadrangle, Harney County, Oregon

[markb]

If you aren't aware, the whole area up there is designated as a Wilderness and a Protected Area. This means breaking off or collecting any rocks to take home is off limits. You are welcome to hike around and enjoy the area, take photos of interesting rocks or formations and so forth, but are not to destroy or take anything out.

As an alternative there is lots of helpful information about places to go rockhounding legally in Oregon, or you could join up with a local rockhound club and learn through them as well.  Whichever way you choose it's still up to us to be responsible for the actions we take, so knowing the laws will be important regarding collecting.  This is the same for collecting or digging at posted mine claims, on private lands, etc.

The reason I'm sharing all this with you is because I am passionate about protecting the natural resources we have left in Oregon.  In so many cases what seemed like a simple act of innocence by taking only a couple of rocks, sometimes escalates to bringing in and filling several dump trucks with obsidian from Glass Buttes, breaking off or chipping away irreplaceable cave formations from caves that are now gated and locked away from public access, or many reports of mine claim jumping and trespass on private land.

I hope you will consider this response in the manner in which it was intended, so hopefully in the future we can retain the privilege of legal rock collecting in Oregon.  

[doublebluff]

Wow- lots of stuff. The webpage is interesting and I certainly didn't know picking up rocks there is a no-no. The pictures are of huge rocks that ten of us could not move one inch. I picked up one softball-sized chunk that I will take back on my next visit, no problem. I truly appreciate all the information.

[Tommy]

Aug 10, 2022 22:04:54 GMT -5 doublebluff said:

I have traveled to Wildhorse lake in the Steens Mountains twice over the past couple years- it is truly wonderful. A brutal hike for someone who lives at sea level...


The cliffs on the right edge of the lake are made of this kind of rock. The crystals are fascinating. This shows the crystals on edge...


This shows a couple of them on their lateral face. The embedded crystals are about the size of a half-dollar or a little bigger. I wonder if this is enough definition to have you folks help me figure out what kind of rock this is.

I lugged a couple softball-sized chunks out to put in the garden, and a few smaller ones that I might put in the tumbler. It might be kinda soft.

It is a beautiful hike, but very strenuous and at altitude. 

Any thoughts on what the rocks are and how they might have formed? Volcanic, for sure... I think.

I'm glad I was tagged into this thread because until this morning I had never heard of this place and now I want to add it to my very long list of places I'd like to visit. I'm sure you took a lot more pictures of the scenery on your hike so please feel free to post more so we can at least drool over them.

Regarding picking up a pretty rock while hiking in a protected area, obviously the forum does not "PROMOTE" said activities (support or actively encourage, assist) so we'll call it lessons learned. Hopefully every time you look at it in your garden you'll remember that hike and start planning your next one.

[quartzilla]

Plagioclase feldspar phenocrysts in what looks like a basalt.

[doublebluff]

One-year later update: I went back to the same spot and brought the rocks back. I didn't know it was a no-no to take them, but that is not an excuse. I had another great trip. The biggest returned rock is near the bottom center of the top pic. The other pics are: a nice example of the crystals that make the rocks so interesting and a shot of the cirque that the lake I traveled to sits in. Hiking and fishing were good.  

[rockbrain]

Looks like another beautiful trip. Really conscientious of you to take the rock back. Glad you didn't get stopped and caught with it while returning it!

[QuailRiver]

Aug 11, 2022 1:12:42 GMT -5 markb said:

If you aren't aware, the whole area up there is designated as a Wilderness and a Protected Area. This means breaking off or collecting any rocks to take home is off limits. You are welcome to hike around and enjoy the area, take photos of interesting rocks or formations and so forth, but are not to destroy or take anything out.

As an alternative there is lots of helpful information about places to go rockhounding legally in Oregon, or you could join up with a local rockhound club and learn through them as well.  Whichever way you choose it's still up to us to be responsible for the actions we take, so knowing the laws will be important regarding collecting.  This is the same for collecting or digging at posted mine claims, on private lands, etc.

The reason I'm sharing all this with you is because I am passionate about protecting the natural resources we have left in Oregon.  In so many cases what seemed like a simple act of innocence by taking only a couple of rocks, sometimes escalates to bringing in and filling several dump trucks with obsidian from Glass Buttes, breaking off or chipping away irreplaceable cave formations from caves that are now gated and locked away from public access, or many reports of mine claim jumping and trespass on private land.

I hope you will consider this response in the manner in which it was intended, so hopefully in the future we can retain the privilege of legal rock collecting in Oregon.  

When I was in my late teens I worked as a field assistant for a prospecting company based out of Colorado that was owned by a Canadian mining corporation. In the fall of 1980 we did geophysics surveys and filed several claims in eastern Oregon. My wife and I went back to eastern Oregon on a collecting trip in 1990 and I would love to go again before I get too old to. I know that there have been a lot of fed related changes since then but at that time most federal controlled land in eastern Oregon could be collected on and claims could be filled on.

So in looking at a map of the Steens Mt./Wildhorse Creek/Lake area posted on the web, it appears that this is a BLM managed area.
www.blm.gov/visit/wildhorse-creek-wild-and-scenic-river

And according to the following linked rockhound resource web site, lands...

"Managed By
Bureau of Land Management

Regulations

“Gold and silver may be prospected for with hand tools including pans and metal detectors… Recreational panning which does not involve mechanical equipment is permitted in wilderness and wilderness study areas if it does not create surface disturbance or impair the environment.”

“Gemstones and common rock specimens may be collected for private use on unclaimed sites.”

“Common invertebrate fossils such as plants, mollusks, and trilobites may be collected for personal use in reasonable quantities, but may not be bartered or sold.”

“Petrified wood may be collected up to 25 pounds plus one piece per person per day, with a maximum of 250 pounds per person per year. Permits are required for pieces over 250 pounds.”

Exceptions & Details

In addition to the local regulations set for each National Conservation Area, there are some important exceptions and restrictions to take note of:
• Collecting specimens in the Red Rock Canyon and the Sloan Conservations Areas is not permitted
• Do not take anything from private mining claims
• Restricted areas and mining claim records can be viewed in BLM offices
• You may only take ‘reasonable amounts’ of material from BLM land
• You may not sell or trade the material you collect
• No digging or surface disturbance is allowed
• No vertebrate fossils may be collected
• No cultural materials such as arrowheads and artifacts may be removed"
rockhoundresource.com/rock-collecting-on-public-land-laws-rules-and-etiquette/

So based on this page it would appear that some limited surface collecting is allowed. If this is not correct is there a website you can direct us to for accurate information? Thank you!

[JR8675309]

Isn't that Turkey track basalt in the picture?