Which Formation Do Summerville Megs Come From?

[THobern]

I was wondering which formation produces megalodon teeth in Summerville. Sites such as these claim that they're teeth come from the Hawthorn;

http://www.lowcountrygeologic.com/FossilSharkTeeth/Carcharoclesmegalodon/tabid/53/fossil/4796/Default.aspx

http://www.paleodirect.com/sh6-025.htm

however, I thought that the Hawthorn formation was in Florida and Georgia. Furthermore, this source says nothing about the Hawthorn in Dorchester County.

http://pubs.usgs.gov/of/2000/of00-049/ChapB/Chart.jpg

Can anyone shed any light?

[siteseer]

I can't recall if anyone has ever given me a formation for those teeth. I would ask Lowcountry Geologic for more background. Mark H. is a geologist, as I recall. The Hawthorn has sounded to me like a catch-all or a go-to in many cases. I'm left thinking they might be reworked.

I noticed that LCG provides a date for the Western Sahara megs as Pliocene. I've heard Miocene from everyone else. You'd think we would see great whites from there but I've seen only hastalis (at least one great white has been informally reported from Morocco - unclear if its a same-age deposit or same formation). The presence of hastalis places the age most likely in the Middle-Late Miocene.

I thought Paleodirect's claim that megs from Peru and Chile were all "junk" was unjustified and unprofessional.

I was wondering which formation produces megalodon teeth in Summerville. Sites such as these claim that they're teeth come from the Hawthorn;

http://www.lowcountrygeologic.com/FossilSharkTeeth/Carcharoclesmegalodon/tabid/53/fossil/4796/Default.aspx

http://www.paleodirect.com/sh6-025.htm

however, I thought that the Hawthorn formation was in Florida and Georgia. Furthermore, this source says nothing about the Hawthorn in Dorchester County.

http://pubs.usgs.gov/of/2000/of00-049/ChapB/Chart.jpg

Can anyone shed any light?

[THobern]

In my experience, there are several catch-all's used for selling fossils; people will say that a shark tooth from South Carolina is from the Cooper etc. It's really unprofessional, but a lot of sellers will just give generic information rather than admit that they're unsure. I wouldn't be at all surprised if the teeth from Summerville are reworked. Incidentally, I just sold Northernsharks a Great White from Morocco - it's in his gallery. Thanks for your help.

[siteseer]

Yeah, sometimes teeth go through more than one person before you see it and the site is lost. Sometimes, the seller really doesn't care about the site and never bothered to ask about it. I see it on Ebay. That's why it's best to deal with the person who actually finds the teeth. That's not generally possible, though.

I was really happy with a trade I made with Toothpuller last year. I got a nice selection of shark/ray stuff from him from the Late Cretaceous of New Jersey. He collected it all himself and is very knowledgeable about the geology of the area.

That great white is an interesting tooth for the site. I haven't seen those at shows.

In my experience, there are several catch-all's used for selling fossils; people will say that a shark tooth from South Carolina is from the Cooper etc. It's really unprofessional, but a lot of sellers will just give generic information rather than admit that they're unsure. I wouldn't be at all surprised if the teeth from Summerville are reworked. Incidentally, I just sold Northernsharks a Great White from Morocco - it's in his gallery. Thanks for your help.

[THobern]

Yeah, sometimes teeth go through more than one person before you see it and the site is lost. Sometimes, the seller really doesn't care about the site and never bothered to ask about it. I see it on Ebay. That's why it's best to deal with the person who actually finds the teeth. That's not generally possible, though.

I was really happy with a trade I made with Toothpuller last year. I got a nice selection of shark/ray stuff from him from the Late Cretaceous of New Jersey. He collected it all himself and is very knowledgeable about the geology of the area.

That great white is an interesting tooth for the site. I haven't seen those at shows.

Yeah, I saw that today. A meg from Summerville was listed on eBay as coming from the Chandler Bridge Formation. I pointed out that this was an Oligocene deposit, and they then changed the formation to Hawthorn. I told them that there don't appear to be any Hawthorn exposures in Summerville, and that was then removed. They obviously had no idea what they were talking about, and were simply padding the sale with vague misinformation. I certainly won't be buying anything from them - it's incredibly unprofessional to sell something authoratively without any research or understanding. However, I suspect that this happens all the times with sales were the seller is unsure - usually there's no way to tell, and it's better for them to add more information. Steven Alter is really good at giving accurate information on ages and formations.

I do prefer to buy from the finder as you get all the information. Add to that, it's usually cheaper as it hasn't passed through several hands.

[DeloiVarden]

Okay guys, since I live within a few miles of Summerville and have collected there I will weigh in. First off, most collectors of fossils are not paleontologists or geologists. Just becuase they sell fossils doesn't mean they should be held to the same standard! Do baseball car collectors have to be baseball players? As for land finds of Megs or any other shark tooth species. Geological movement often clouds the picture since layers are not always present at the same elevation and thus sediment can easily get reworked both by nature and by man. Much of the Summerville stuff is Oligiocene due to the relative shallow exposure to Oligiocene deposits in the area. Oligiocene specific species such as Angustidens are common and side cusped benedeni are also present. However, there is a shallow layer of more recent material in the area as well. How do I know this? Well, I have found megalodon teeth in Summerville as well. In the case of deep rivers like the cooper, the river can cut deep through many different layers. So when a diver collects teeth out of a gravel bed on the bottom, it is near impossible to date the fossil let alone know the exact layer it came from. In such cases, a best guess as to the age is not a lie, it is a best guess. Though there are a lot of resellers out there who don't have exact info on where a particular fossil was found, generally divers and land collectors who sell there may not akways be able to tell you the geology of the layer a fossil came from, but they certainly know where they found it. Though I and most others are not going to give you GPS coordinates.

Edited March 7, 2011 by DeloiVarden

[DeloiVarden]

On another note, if you do know more about geological layers found in a specific area, be nice and share the knowledge so that they will be better informed in the future. One of the purposes of forums such as this is to share knowlege. There is no need to villianize the sellers out there just because they are not as well read as you may be.

I will also add that state geologist that are often responsible for documenting the exact locations of particular geological layers have not walked every square inch of ground nor seen the amount of exposures that many collectors have. So there may be cases where layers extend into areas not currently documented in literature.

Edited March 7, 2011 by DeloiVarden

[sixgill pete]

Very well said, DeloiVarden. I collect from many places, I could not tell you the formations of all of them. Most of the information I get about age is from a website or book.

[Paleoc]

I thought Paleodirect's claim that megs from Peru and Chile were all "junk" was unjustified and unprofessional.

"Do not confuse this tooth with the junk coming out of Peru and Chile. Those teeth are NOT rare and their very low prices on the market indicate this. Furthermore, Megalodon teeth from South America are not mineralized very well and most are rotten, easily falling apart if not properly stabilized. " http://www.paleodirect.com/sh6-025.htm

I will second your comment. I have a 5 3/4 inch Chilean meg which is probably the most solid meg I own. It is literally solid and heavy as a rock. It is certainly well mineralized and as I had to scrape a lot of matrix off of it, it is not repaired or going to fall apart.

Edited March 7, 2011 by Paleoc

[DeloiVarden]

Thanks sixgill pete.

A quick web search clarifies that it is generally accepted that the Oligocene Epoch lasted from 34-23 million years ago and it is believed that megalodon roamed the earth approximately 25 to 1.5 million years ago (late Oligocene to Pleistocene Epoch). Thus Megalodon shark teeth would be expected to be found in late Oligocene deposits like the Chandler Bridge of Summerville since there is approximately 2 million years of overlap. I have also attached an interesting research paper regarding the Chandler Bridge Formation. Though the paper does not make mention of Megalodon, it does date the Summerville Chandler Bridge to the late Oligocene Epoch. So next time you see a Summerville Megalodon listed as Oligocene, don't be so quick to discount it.

KnightChandlerBridge.pdf

Edited March 7, 2011 by DeloiVarden

[THobern]

Thanks sixgill pete.

A quick web search clarifies that it is generally accepted that the Oligocene Epoch lasted from 34-23 million years ago and it is believed that megalodon roamed the earth approximately 25 to 1.5 million years ago (late Oligocene to Pleistocene Epoch). Thus Megalodon shark teeth would be expected to be found in late Oligocene deposits like the Chandler Bridge of Summerville since there is approximately 2 million years of overlap. I have also attached an interesting research paper regarding the Chandler Bridge Formation. Though the paper does not make mention of Megalodon, it does date the Summerville Chandler Bridge to the late Oligocene Epoch.

Not true. Even pushing megalodon back to 25 mya, those teeth would be early subauriculatus/chubutensis teeth. Summerville produces teeth that are definitely past this stage. Furthermore, the size of some Summerville teeth is far larger than the teeth found 25mya. Really large Summerville teeth are rare, but there are enough over the 6" mark to assume that there are deposits from the middle-Miocene.

[THobern]

"Do not confuse this tooth with the junk coming out of Peru and Chile. Those teeth are NOT rare and their very low prices on the market indicate this. Furthermore, Megalodon teeth from South America are not mineralized very well and most are rotten, easily falling apart if not properly stabilized. " http://www.paleodirect.com/sh6-025.htm

I will second your comment. I have a 5 3/4 inch Chilean meg which is probably the most solid meg I own. It is literally solid and heavy as a rock. It is certainly well mineralized and as I had to scrape a lot of matrix off of it, it is not repaired or going to fall apart.

That's anecdotal, but I agree; Chile especially produces a lot of solid teeth. A lot of Peruvian teeth are weathered and in need of stabilisation, but his point is still well off the mark.

[THobern]

Okay guys, since I live within a few miles of Summerville and have collected there I will weigh in. First off, most collectors of fossils are not paleontologists or geologists. Just becuase they sell fossils doesn't mean they should be held to the same standard! Do baseball car collectors have to be baseball players? As for land finds of Megs or any other shark tooth species. Geological movement often clouds the picture since layers are not always present at the same elevation and thus sediment can easily get reworked both by nature and by man. Much of the Summerville stuff is Oligiocene due to the relative shallow exposure to Oligiocene deposits in the area. Oligiocene specific species such as Angustidens are common and side cusped benedeni are also present. However, there is a shallow layer of more recent material in the area as well. How do I know this? Well, I have found megalodon teeth in Summerville as well. In the case of deep rivers like the cooper, the river can cut deep through many different layers. So when a diver collects teeth out of a gravel bed on the bottom, it is near impossible to date the fossil let alone know the exact layer it came from. In such cases, a best guess as to the age is not a lie, it is a best guess. Though there are a lot of resellers out there who don't have exact info on where a particular fossil was found, generally divers and land collectors who sell there may not akways be able to tell you the geology of the layer a fossil came from, but they certainly know where they found it. Though I and most others are not going to give you GPS coordinates.

That's true; collector's can't always give you specific information. If you meant that as a counterargument to my point, what I meant was that sellers shouldn't provide information that the don't have - details that they don't really know. That's a different expectation from demanding that sellers should be obliged to provide more information than they have.

[non-remanié]

my guess is that they are reworked into surficial fluviatile? pleistocene gravel deposits that often cap the chandler bridge fm but can be hard to characterize or differentiate. perhaps they originated from the hawthorne even though it has been completely eroded in that area.

[Northern Sharks]

For what it's worth, the Paleobiology Database has the Hawthorn Fm. as going into South Carolina and being early miocene in age

http://www.paleodb.org/cgi-bin/bridge.pl?action=displayStrata&geological_group=&formation=Hawthorn&group_formation_member=Hawthorn

[DeloiVarden]

Not true. Even pushing megalodon back to 25 mya, those teeth would be early subauriculatus/chubutensis teeth. Summerville produces teeth that are definitely past this stage. Furthermore, the size of some Summerville teeth is far larger than the teeth found 25mya. Really large Summerville teeth are rare, but there are enough over the 6" mark to assume that there are deposits from the middle-Miocene.

I did acknowledge more recent deposits than Oligocene in the Summerville area in one of my posts. I won't continue to argue the age range of Megalodon though there is hardly agreement that Megalodon did not exist during the late Oligocene, but will end by saying that many of the megatooth shark species did not start their existence day one of a particular epoch and end their existence on the last day of that Epoch. The conversation regarding Rics, Angys, Megs and, if you will, Sokolovi and Chub too, continues. There is hardly agreement among the experts, so it doesn't suprise me that we can have a good discussion on it. But lets be nice.

Edited March 7, 2011 by DeloiVarden

[siteseer]

THobern and I were referring only to sellers who intentionally misrepresent their material and he provided an example (the guy who flip-flopped on the formation when called on it). If the seller doesn't know the formation, that's okay, but he shouldn't pull one out of thin air if he thinks it will help make a sale. That was all we meant to say - no slight intended toward honest people.

As for providing info, if you go through my posts, you'll see I do that whenever I can.

On another note, if you do know more about geological layers found in a specific area, be nice and share the knowledge so that they will be better informed in the future. One of the purposes of forums such as this is to share knowlege. There is no need to villianize the sellers out there just because they are not as well read as you may be.

[PaleoDirect]

That's anecdotal, but I agree; Chile especially produces a lot of solid teeth. A lot of Peruvian teeth are weathered and in need of stabilisation, but his point is still well off the mark.

To clarify, the information on our website is not timeless and since we keep many sold items forever in the sold archives, some of the information will certainly seem dated or out of place. I think this listing dates back to nearly a decade ago. At that time, Peruvian and Chilean fossil shark teeth were not illegal to export or take home and collecting there was not as popular as it became. Much of what we saw at that time of the listing WAS junk from Chile and while the teeth from Peru were nicer, the majority of them were junk too. We don't date stamp the listings so it may seem that sold items are recent but many that are there in those sections can be from as early as 2001.

Over the course of the last decade, shark teeth from Peru have become much better and appreciated more. Since that time, the locals and tourists have come to Ica and scoured the deposits, building nice collections of very attractive and expensive teeth because it became like a "gold rush" to the poor locals. To this day, the teeth are routinely smuggled out so while it is technically illegal now, the teeth seem to still find there way to U.S. markets since prices have gone up.

It's hard to predict the future but to put that listing in perspective, AT THE TIME OF THE PAGE'S POSTING, this was true about conditions of the majority of the teeth that were being found and sold. To be honest, I'm stunned at the prices the teeth fetch here now. They are very cheap and more plentiful over there than the market reflects here. For those that risk sneaking them out, the monetary gain is very high.

[PaleoRon]

I have collected the Summerville deposits on several occasions many years ago and the few times I found a megalodon tooth in situ it was in a lag deposit that contained Oligocene marine fossils as well as Pliocene/Pleistocene land mammal fossils. I have heard that solid (primary deposition) Hawthorne formation can be found in rivers south of Summerville, but it seems to have been beveled off in the Summerville area.

I would agree that some dealers have no idea where their fossils come from or what age they are and the ethical thing to do is simply admit it. Unfortunately there are others who intentionally mislead potential buyers by listing teeth as coming from rare locations or listing them as a different (and rare) species.

[Harry Pristis]

There are many questions about the nature and the extent of the Hawthorn Formation in Florida where it was first described. The inclusion of some South Carolina features into the Hawthorn lithology must complicate the questions even further.

Here's a discussion of Florida geology in a summary format:

http://www.clas.ufl.edu/users/guerry/GLY4155/mio_holo.htm

[Harry Pristis]

I did acknowledge more recent deposits than Oligocene in the Summerville area in one of my posts. I won't continue to argue the age range of Megalodon though there is hardly agreement that Megalodon did not exist during the late Oligocene, but will end by saying that many of the megatooth shark species did not start their existence day one of a particular epoch and end their existence on the last day of that Epoch. The conversation regarding Rics, Angys, Megs and, if you will, Sokolovi and Chub too, continues. There is hardly agreement among the experts, so it doesn't suprise me that we can have a good discussion on it. But lets be nice.

At Elasmo.research.org, it says:

". . . for all the contention [the Carcharocles-Carcharodon debate] over the correct genus to assign to Megalodon, most paleontologists agree on three main points: Megalodon was a relatively recent species, appearing in the fossil record only about 16 million years ago and disappearing suddenly about 1.6 million years ago; Cretolamna appendiculata is most likely an ancestor of Megalodon; and that Megalodon is not a direct ancestor of the modern White Shark, more like a great uncle or aunt." [emphasis added]

It's impossible to prove a negative: "C. megalodon did not exist in the Oligocene."

BUT, the positive is provable: "No fossil evidence is known for C. megalodon existing in the Oligocene."

Science is evidence-based. Show us your evidence for Oligocene megs.

[Al Dente]

At Elasmo.research.org, it says:

". . . for all the contention [the Carcharocles-Carcharodon debate] over the correct genus to assign to Megalodon, most paleontologists agree on three main points: Megalodon was a relatively recent species, appearing in the fossil record only about 16 million years ago and disappearing suddenly about 1.6 million years ago; Cretolamna appendiculata is most likely an ancestor of Megalodon; and that Megalodon is not a direct ancestor of the modern White Shark, more like a great uncle or aunt." [emphasis added]

It's impossible to prove a negative: "C. megalodon did not exist in the Oligocene."

BUT, the positive is provable: "No fossil evidence is known for C. megalodon existing in the Oligocene."

Science is evidence-based. Show us your evidence for Oligocene megs.

Harry-

While I'm not a firm believer in an Oligocene age for megalodon, there are several sources that claim a Late Oligocene age for the species.

One is from Gottfried and Fordyce ( 2001) Journal of Vertebrate Paleontology. Vol. 21, #4 pp. 730-739.

An Associated Specimen of Carcharodon Angustidens (Chondrichthyes, Lamnidae) from the Late Oligocene of New Zealand, with comments on Carcharodon interrelationships.

"…However, Keyes (1972:fig. 10) includes a large upper anterior tooth (OU 10768, 150 mm in height) from the Chatton Marine Formation of Waimumu, Southland (South Island). OU 10768, which we reexamined, appears to quite clearly be C. megalodon, and to be accurately dated as Late Oligocene…"

Also on the elasmo.com website:

"Upper teeth of Carcharocles from the Late Oligocene Chandler Bridge Fm. of South Carolina sometimes lack cusplets so technically must be called C. megalodon."

In your quote about megalodon, it said they existed until 1.6 million years ago. I would be interested to see citations that support this statement. The youngest teeth I'm aware of are from the base of the Sunken Meadow member of the Yorktown Formation, Lower Pliocene, possibly 4 or 5 million years old.

[non-remanié]

Seems like an argument based in semantics to me. I believe in the chrono-species reasoning. There was one big Carcharocles at any given time. Such small changes in tooth form, probably meant very little to the overall nature of the beast, but since the teeth are so large the small variations seem significant to us collectors so we have to give each a different name. But even within this simple statement it acknowledges that only one tooth position sometimes shares this characteristic of looking like a megalodon and lacking cusplets. So even if that is true, if the species were distinct from the other species present at the time (angustidens) then we would have more than just uppers that match megalodon. Otherwise calling it a megalodon doesn't really have much meaning...

"Upper teeth of Carcharocles from the Late Oligocene Chandler Bridge Fm. of South Carolina sometimes lack cusplets so technically must be called C. megalodon."

[Harry Pristis]

Seems like an argument based in semantics to me. I believe in the chrono-species reasoning. There was one big Carcharocles at any given time. Such small changes in tooth form, probably meant very little to the overall nature of the beast, but since the teeth are so large the small variations seem significant to us collectors so we have to give each a different name. But even within this simple statement it acknowledges that only one tooth position sometimes shares this characteristic of looking like a megalodon and lacking cusplets. So even if that is true, if the species were distinct from the other species present at the time (angustidens) then we would have more than just uppers that match megalodon. Otherwise calling it a megalodon doesn't really have much meaning...

I think 'toothpuller' has made his case. An odd tooth, or even a few odd teeth, without cusplets mean very little when trying to determine the age-range of this species. A savvy collector has to rely on all available information; morphological characters don't convey the whole picture. (That single NZ specimen is suspect just because it is a singleton.)

Here's how David J. Ward describes the question of Oligocene megs:

"There are two conflicting classifications. The first - morphospecies - is just shape-based. Thus, if it is big, with no lateral cusps, it is a meg. The other, more scientific approach, attempts to get closer to a zoological species."

Because there are well-known allometric form changes in the Carcharocles group of species, and because atypical specimens may occur in any species, an occasional tooth without lateral cusps should not make much of a ripple on the taxonomic pond.

[Auspex]

...Because there are well-known allometric form changes in the Carcharocles group of species, and because atypical specimens may occur in any species, an occasional tooth without lateral cusps should not make much of a ripple on the taxonomic pond.

Well said!