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Keep seeing old geology used in recent paleontological literature and was wondering what the cause was. The local Pliocene Bear Bluff Formation for instance was changed to the Goose Creek Limestone a couple of decades ago. Also have seen the Campanian Black Creek Formation used when it is the Black Creek Group containing three formations. This also for over 20 years. Sort of the same deal for the Paleocene Beaufort Formation elevated to a group a long time ago. Question is whether the usage is a disagreement with the revised nomenclature or ignorance. The reason I mention ignorance, not the negative connotation of the word, is because google searches are tough for literature searches originating is relatively obscure publications. This may be a cautionary tale of depending on literature found easily on line. I enjoy reading paleontology articles, particularly those with subjects involving North Carolina taxa. 

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Great question, and it may be tough to pinpoint one cause as it may be different depending on who is authoring the paper. I do know that nothing can devolve into fisticuffs faster for geologists than disputes over stratigraphy! I know the stratigraphy of my province keeps changing, and it goes through its phases of lumping and splitting, occasionally demoting a formation to a member. For some, there is a preferential attachment to a formation name as something they've always known it as, or something they feel ought to be the case. This can create a lot of confusion and headaches. On top of that, how we cut the strata will definitely differ depending on which "camp" one belongs in. Is it by index fossils or conodont zones? Lithology? And where do we make that cut if the formations are gradational? 

 

If we add in online research, it can be simply a matter of going for what comes up first, and if the researcher is not up on particulars of the stratigraphy, they might take it as true and still relevant. So that would definitely speak to the ignorance (in the non-offensive connotation) you mentioned. 

 

Very interesting topic! 

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DPS Ammonite
13 minutes ago, Kane said:

On top of that, how we cut the strata will definitely differ depending on which "camp" one belongs in. Is it by index fossils or conodont zones? Lithology?

In the US and probably Canada too (I’d love to know), rock units (lithostratigraphic) such as groups, formations and members should only be defined by lithology and stratigraphic relations.

 

See:

https://stratigraphy.org/guide/litho

 

Biostratigraphic units are only defined by the fossils and can meander over several lithostratigraphic units.

 

As Kane pointed out, there are disagreements over the naming and definition of lithostratigraphic units. For example in Arizona, one worker renamed part of the Supai Formation as the Schnebly Hill Formation. Subsequently several geologists said that the Schnebly Hill Fm. contacts could not be recognized and mapped in many areas. I agree. I am confused too. 

 

 

 

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Tidgy's Dad
Posted (edited)

It is a bit of a headache. 

I am currently working on some fossils from the Late Ordovician (sometimes Upper Ordovician) Mount Auburn material. 

Now, the literature for Ohio often lists this as being the Mount Auburn Member of the McMillan Formation. 

In Kentucky it is the Mount Auburn Formation. Or, sometimes the Grant Lake Limestone, Mount Auburn Member. 

On occasion in Indiana it is the Mount Auburn member of the Dillsboro Formation. 

And it was part of the Ashlock Formation in something else I read. 

Some of these papers are pretty old, but many are quite recent and though I think it's now officially the Grant Lake Formation, Mount Auburn Member, people seem to go with what they know of old, or just what they prefer. 

And I won't start on whether one of the brachiopods from the Mount Auburn is Platystrophia ponderosa auburnensis, Vinlandostrophia ponderosa auburnensis, Vinlandostrophia auburnensis or Gnamptorhynchos auburnensis. 

:shrug:

Edited by Tidgy's Dad
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DPS Ammonite
1 hour ago, Plax said:

Keep seeing old geology used in recent paleontological literature and was wondering what the cause was. The local Pliocene Bear Bluff Formation for instance was changed to the Goose Creek Limestone a couple of decades ago. Also have seen the Campanian Black Creek Formation used when it is the Black Creek Group containing three formations. This also for over 20 years. Sort of the same deal for the Paleocene Beaufort Formation elevated to a group a long time ago. Question is whether the usage is a disagreement with the revised nomenclature or ignorance. The reason I mention ignorance, not the negative connotation of the word, is because google searches are tough for literature searches originating is relatively obscure publications. This may be a cautionary tale of depending on literature found easily on line. I enjoy reading paleontology articles, particularly those with subjects involving North Carolina taxa. 

Here is a great site that I use to help sort lithostratigraphic units out most of the time. Geolex. The easiest thing to do is put in the name of the unit without the rock type or type of unit along with the term “Geolex”.  References are organized chronologically. Pay more attention to the newer ones. 

 

https://ngmdb.usgs.gov/Geolex/UnitRefs/BearBluffRefs_316.html

 

https://ngmdb.usgs.gov/Geolex/UnitRefs/GooseCreekRefs_1829.html

 

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siteseer

I have seen this too with regard to the Sharktooth Hill Bonebed.  One hundred years ago, it was considered to be within the Temblor Formation but the regional stratigraphy was reviewed and the formation was named the Round Mountain Silt (proposed in the 30's, adopted in the early 40's).  This was reviewed further (Addicott, 1970, Bartow and McDougall, 1984) with the Round Mountain Silt confirmed as the valid name.  There is a Temblor Formation but it has been determined to be exposed several miles to the north and not connected to the Round Mountain Silt other than being around the same age.

 

What causes confusion is that even in the past 10-20 years some paleontologists refer to older papers without consulting more recent reviews of the geology so they use the old names.

 

Addicott, W.O. 1970.

Miocene gastropods and biostratigraphy of the Kern River area, California. USGS Professional Paper 642. 174 p.

 

Bartow, J.A. and K.A. McDougall. 1984.

Tertiary stratigraphy of the southeastern San Joaquin Valley, California. USGS Bulletin 1529-J. 41 p.

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DPS Ammonite

There is a partial solution, when using a name say that it is being used in the same manner as a worker in a specific reference.

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LabRatKing

I feel it is a direct result of the advent of more unified databases and journals. For decades, there really wasn’t any unified source- different authors published by what was available. Much as we see in the biological sciences these days, near instantaneous cross referencing has exposed this issue-

 

in other words, tradition vs. technology is in a transition period between the old school and new school.

 

personally I’m struggling with it as technically many of the fossil bearing strata I play in have dozens of names depending on location, but in reality are all pretty much the same formations! (South Dakota to Kansas)

 

it’s really confusing when one realizes the older papers use different names as tech at the time didn’t allow for the vast expanses of geologic scale...and traditionally authors really wanted their nomenclature used...

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Ludwigia

Aren't there recognized worldwide commissions on stratigraphy for each Period which attempt to make up-to-date recommendations on lithological and biostratigraphical units and their correlation on a worldwide basis? I know several members of the Jurassic Commission here in Europe and they do pretty good work keeping things as current as possible. Here's the international one anyway.

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16 hours ago, DPS Ammonite said:

Here is a great site that I use to help sort lithostratigraphic units out most of the time. Geolex. The easiest thing to do is put in the name of the unit without the rock type or type of unit along with the term “Geolex”.  References are organized chronologically. Pay more attention to the newer ones. 

 

https://ngmdb.usgs.gov/Geolex/UnitRefs/BearBluffRefs_316.html

 

https://ngmdb.usgs.gov/Geolex/UnitRefs/GooseCreekRefs_1829.html

 

Have seen this come up in searches and chased references from this starting point. If one searched Bear Bluff though I don't see where it says the name was superseded by the Goose Creek in the summary. It does have a cross in the usage section of Mathew Campbells '92 Tulane paper though. Am guessing these citations leave the conclusions up to the researcher and simply cite the literature relevant to the inquiry. I like the chronological order especially with the Black Creek Group. At a point in time it changes from Formation to Group. I guess this is because the name is the same. Wouldn't make sense for the Bear Bluff to change into the already existing (chronologically) Goose Creek. Great resource.

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LabRatKing
On 5/3/2021 at 4:02 PM, Ludwigia said:

Aren't there recognized worldwide commissions on stratigraphy for each Period which attempt to make up-to-date recommendations on lithological and biostratigraphical units and their correlation on a worldwide basis? I know several members of the Jurassic Commission here in Europe and they do pretty good work keeping things as current as possible. Here's the international one anyway.

Yeah, there is, but the vast amounts of historical reports can make it difficult to cross reference in my experience thus far...and I get the distinct impression that they haven’t gotten through a lot of the new world stuff prior to the 70s yet.

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Ludwigia
9 hours ago, LabRatKing said:

Yeah, there is, but the vast amounts of historical reports can make it difficult to cross reference in my experience thus far...and I get the distinct impression that they haven’t gotten through a lot of the new world stuff prior to the 70s yet.

This is true, but as we all know, nobody's perfect.

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erose
On 5/3/2021 at 1:40 PM, Tidgy's Dad said:

It is a bit of a headache. 

I am currently working on some fossils from the Late Ordovician (sometimes Upper Ordovician) Mount Auburn material. 

Now, the literature for Ohio often lists this as being the Mount Auburn Member of the McMillan Formation. 

In Kentucky it is the Mount Auburn Formation. Or, sometimes the Grant Lake Limestone, Mount Auburn Member. 

On occasion in Indiana it is the Mount Auburn member of the Dillsboro Formation. 

And it was part of the Ashlock Formation in something else I read. 

Some of these papers are pretty old, but many are quite recent and though I think it's now officially the Grant Lake Formation, Mount Auburn Member, people seem to go with what they know of old, or just what they prefer. 

And I won't start on whether one of the brachiopods from the Mount Auburn is Platystrophia ponderosa auburnensis, Vinlandostrophia ponderosa auburnensis, Vinlandostrophia auburnensis or Gnamptorhynchos auburnensis. 

:shrug:

I tried to sort out the Cincinnatian many years ago for a NYPS field guide I put together. You are right that between old and new work and Ohio, or Kentucky, or Indiana it is a bit of a nomenclatural mess.

 

This is why I tell folks that location information with each specimen is more important than trying to get the stratigraphy correct.  The names can change, and they will, but the location will be certain.

 

On the larger picture here, I think it is always important to find multiple sources and try and be critical.  

 

And yes it does really help when if they list a formation name they at least include the reference or a footnote.

 

And one last consideration. Sometimes the lag between submittal and final publication can mean the most current material gets left out. 

 

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"and the most current material gets left out"

  This happened a lot back in the day. Am reminded of Jerry Case's "Trent" paper. It came out in '80 I think and Ward's revision (losing the "Trent" name) of those strat came out in '78. Nothing more annoying than someone criticizing papers from back in the day when one had to know of a physical paper coming out in order to stay up to date. It was sort of a grapevine scenario where you depended on associates that knew what was out there. You couldn't stay in your own brain or you would never know what was happening as far as research. Much easier now of course! 

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