Wild trout, Geology, & Bedrock. More info?

[steveo27]

Ive fished the other stream you just mentioned as well (north of #2 and east of the golf course) and it doesnt fish as well as stream number 1. Again, I can understand why now.

How do you do the bed rock layer on Google Earth?

Thanks for the info.

 

[k-bob]

I think if you put "Pennsylvania Bedrock layer Google Earth" in Google.

You should get results from the USGS... then click the link that ends in .kml or .kmz can't remember which.. once you click that link the Bedrock information should appear in the left-hand panel under the list of locations in google earth and you can save it...

I changed the Google Earth Pa Bedrock layer's default colors for burgoon and mount Chunk and pottsville in that image above.... and made them transparent using the properties setting once you click a bedrock on the map....

I try to make Google Earth look like the state maps because I know some of the state maps colors...

 

[k-bob]

good that your fishing experience on a few of these tribs fits w/ the ideas from geology/buffering. of course all the other stuff (drainage area, shade, pools, etc) matters as well (I like steep streams for ex and they often have brookies).

and there can be streams with great habitat and on-the-edge buffering that still fish well and are fun to fish. but they may be more cyclical, worse damage in a bad snowmelt.

 

[k-bob]

btw, this forest study has stream pH data from SWPA, NWPA and WV/MD. there's a map showing studied regions.

see the third and fourth lines of Table III for stream pH by bedrock

they show stream pH as lowest in Pottsville and Alleghany, then higher for Catskill, Pocono, & Chemung, higher again for Mauch Chunk and Greenbriar... differences look pretty big... may be good input for swpa

https://www.nrs.fs.fed.us/pubs/jrnl/2005/nrs_2005_williard_001.pdf

"Watersheds were grouped into three geologic categories: Pottsville and Allegheny sandstone (PVA), Catskill, Chemung, and Pocono shale and sandstone (CCP), and Mauch Chunk shale and Greenbrier limestone (MCG) ... PVA, CCP, and MCG bedrock types, respectively, exhibit low, intermediate, and high bedrock fertility and groundwater pH values"

 

[k-bob]

article in previous post shows pH of 5.03-5.1 for the Pottsville and Allegheny influenced streams. if you consider figure ten below (on original source's page 20), it gives dissolved aluminum as a function of water pH w/ the red dashed line showing the lethal level for brookies... streams in pottsville may not have trout.

http://www.ncdoj.gov/getdoc/6741ebbc-1bb7-44b4-b097-73bd1c23bbc3/Driscoll-Expert-Report.aspx

same thing, pH about 5 due to acid deposition and low buffering (and sometimes bog headwaters), can happen in some burgoon influenced tribs in nepa, stream pH in table 3-1 here:

http://www.wehydro.com/images/2007fc.pdf

If i just look at the drainage area, forestation, and gradient, I would like to fish Blackberry run up there, but once you see that the pH is about 5....

 

[Fly-Swatter]

That East Branch FC proposal looks solid. What ever became of it?

 

[Chaz]

For what it's worth, the bedrock also determines the types of vegetation on the surface, and the vegetation also contributes to the stream ph. Probably minor but it's there.

 

[k-bob]

relationship between water pH and dissolved aluminum (see post 25)

 

[BrooksAndHooks]

I don't have the educational background you guys do. Could you shine some light on what to look for specifically other than limestone is good, etc. Thanks!

 

[k-bob]

background: when it comes to acid rain effects, we have everything in PA from limestone valley streams where the limestone bedrock buffers away any acid rain effect, to some mountain tribs that flow through low buffering bedrocks and have no trout at all.

bedrock geology might matter to trout populations in small headwaters mountain streams (down in valleys the buffering is often higher.)

if the bedrock geology that a mountain trib has flowed through has very low buffering capacity, there may even be zero trout due to acid rain. this can happen for example with Pottsville bedrock which covers 15% of PA, and exists in both eastern and western PA (there is a large area of Pottsville bedrock in NWPA).

of course habitat, pools, water temp, not drying out, etc. have to be considered... as I can say from first hand fishing experience, a dried out streambed in high buffering bedrock does not fish well 🙂

interestingly, lower and higher buffering bedrocks can be right next to each other. in Schuylkill, it could be Pottsville bedrock (lower buffering) next to Mauch Chunk bedrock (higher). in Sullivan, it could be Burgoon bedrock (lower buffering) next to Huntley bedrock (higher). In Centre, it could be Tuscarora bedrock (lower buffering) next to Juniata bedrock (higher).

so you might check whether a mountain trib has flowed through a bedrock area with some buffering above where you fish it.

this map can show you the bedrocks. hit geology tab upper right.
http://www.gis.dcnr.state.pa.us/maps/index.html

actually using bedrock info isn't too bad in NEPA, SEPA, NCPA, and SWPA, because there are fewer bedrock types in the mountain tribs. but in SCPA or around centre county there are more bedrock types and more changes (see map linked above).

here are some bedrocks with my thought on how I would look at a mountain trib section that has mostly flowed through them... this wont begin to cover all the bedrocks out there, but there are some common ones mentioned, particularly in NEPA, NCPA, & SWPA mountain areas:

what to look for:

bedrocks that are a bad sign for trout: Pottsville, Allegeheny, Llewlyn, Burgoon, Tuscarora. Montalto, and other bedrocks mentioning quartz when you click the bedrock color in linked map above. also mentions of coal in the descriptions of any bedrock in map linked above (thanks Pat).

moderate: Pocono, Chemung, Reedsville, Coburn, Clinton, Lock Haven, Hamilton, Bloomberg & Mifflin, Mahantango, Trimmers, Bald Eagle, Spechty Kopf.

nice: Mauch Chunk, Huntley, any of Catskill bedrocks, Shawangunk, Juniata. mentions of dolomite or limestone if you click the bedrock color in linked map above.

btw, if a stream emerges from swamps, it may have natural acid from plant decay so it may need more buffering...

 

[k-bob]

in central & south-central PA, mountain tribs that have flowed mostly through low-buffering Tuscarora bedrock may not be so good. other mountain tribs in Pocono or Clinton bedrock might be better than the Tuscarora ones.

 

[k-bob]

I see some SCPA tribs in Mauch Chunk or Juniata bedrock... if the habitat, pools, etc., look OK, they might be better than a Bald Eagle, Pocono, or Clinton bedrock one, with tribs in Pottsville, Allegheny, or Tuscarora bedrocks a last choice as far as buffering goes.

 

[BrooksAndHooks]

k-bob,

thanks for taking the time to respond to me. Very to the point and told me what I needed to know. I appreciate it a lot. I have a lot of "bad" around me, lots of brook trout streams, but I am finding the browns slow but surely as well. This is just another piece to the puzzle when it comes to identifying possible new streams to check out.

Thank you again,

Ryan

 

[k-bob]

I haven't been in SCPA much, but some parts of the mountainous state forest tracts there are tuscarora bedrock, so they may not have trout.

"Dissolved aluminum concentrations were much higher for Tuscarora streams (0.2 mg/L; approximately the lethal limit for brook trout) than for non-Tuscarora streams (0.03 mg/L)" (abstract of nice Kirby paper on acid deposition, PA bedrocks, and trout, (link below)).

https://www.ncbi.nlm.nih.gov/pubmed/18258282

but sometimes there is also juniata bedrock, and that would be a better sign as long as the water temps, habitat, etc., are there

browns may be less acid tolerant than brookies, they might be in streams with more highly buffering bedrocks.

 

[streamerguy]

Great thread guys! Been thinking about this stuff lately as well. I'm currently a geology undergrad, so this is all super cool. Need to take the time to dig through some of those sites.

 

[k-bob]

great that you are studying geology... I went to three schools (all in Ohio) but never did! the old McPherson sawtooth chem building at ohio state was so crazy that I studied business 🙂

http://kb.osu.edu/dspace/bitstream/handle/1811/37582/05_0003707.jpg;jsessionid=D26FBD690C3B197CCCED602C2549A285?sequence=1

I find it is easier to use geology info in a few PA areas because of reports like the one linked below for Sullivan County, giving a bedrock geology map & well water pH by bedrock... (well water pH is a signal of relative buffering)

https://pubs.usgs.gov/sir/2013/5085/support/sir2013-5085.pdf

nice. but there usually aren't such reports available, so just putting the bedrock name in a google search like this "Tuscarora bedrock USGS" and looking for the "Mineral Resources" results may give you a "quick and dirty /better than no info" signal for at least a few bedrocks.

for ex, the USGS Mineral Resources result from a "Tuscarora bedrock USGS" google search includes:

"Primary rock type
quartzite

Secondary rock type
sandstone

Other rock types
shale; siltstone; conglomerate"

primarily quartz, and quartz is low buffering ("The ability to neutralize acid is called buffering capacity. Quartzites have a low-buffering capacity." see link below). mentions of coal in such results could also signal buffering issues.

http://www.bobpickett.org/08-08%20Tuscarora%20sandstone.htm

the USGS Mineral Resources result for a "Juniata bedrock USGS" search includes:

"Primary rock type
sandstone

Secondary rock type
shale

Other rock types
siltstone"

well, at least no mention of coal or quartz...

maybe this helps with some PA streams that run off mountains. for example, in the Michaux St Forest SW of Carlisle, there are several streams on the PA state natural trout reproduction list that flow through about .4 mi or more through Tomstown bedrock at the base of a mountain and Montalto bedrock up in their mountain headwaters. (for ex Hairy Springs Hollow listed as "Headwaters dnst to mouth")

these streams might have been surveyed down in the Tomstown stretch; I think streams are often surveyed near their mouths (?).

USGS Mineral Resources result for "Tomstown bedrock USGS" search:

"Primary rock type
dolostone (dolomite)

Secondary rock type
shale

Other rock types"

dolomite is high buffering.

USGS Mineral Resources result for Montalto:

"Primary rock type
quartzite

Secondary rock type

Other rock types"


quartz, and the stream beds up on the mountain are white. I found no trout up on Hairy Springs Hollow's mountain headwaters, and the aluminum was > than the lethal level of .20 at a low/base flow...

so while there probably are wild trout in those listed streams, they may be down in the Tomstown bedrock stretch.. may not be as many trout up in the mountain headwaters ...

of course this business of USGS searches is not as good as well water by bedrock data, but it is sometimes better than nothing (shrug).

for example, I believe I found some trout in montalto bedrock Michaux headwaters streams, but more often did not.

 

[wjkosmer]

k-bob
http://dcnr.state.pa.us/topogeo/publications/pgspub/water/index.htm

 

[k-bob]

thanks, wjk. I like those listings that incl some well water pH by bedrock info. but they have limited data for some mountain bedrock types in some areas. I used some of that data to make the "what to look for lists" post 30. (particularly the middle list)

forgot about these surveys 'round Michaux. the 4 tribs near Michaux w/ trout (sage, iron, tag, and hunters) are in heavily in metarhyolite bedrock, not one listed by usgs as primarily quartz like montalto. ...

http://pfbc.pa.gov/images/fisheries/afm/2009/7x12_16wild.htm

 

[BrooksAndHooks]

Awesome, thanks for all the info! Geology is pretty much the opposite of the field I am in (healthcare) but I am in grad school and doing research so I have a great appreciation for it. Enjoy reading this stuff and utilizing the information greatly. Thanks again!

 

[k-bob]

anyone ever fish limestone run, sgl 51, swpa? I ask because it is on the natural repro list and has some mauch chunk bedrock in its headwaters, plus that name. apparently mauch chunk can have limestone influence in swpa. I winder how it fishes but its out of my sane driving range 🙂