Shark Tooth Hill----- Calif.

[RichW9090]

Lisa and Jess, I do not know which quarry I worked in with Bob - he didn't refer to it by a name. But the nodule sat right at the entrance to the quarry, beside his access road.

Edited August 19, 2013 by RichW9090

[fossil26]

That's an interesting find ! Land mammals are few and far between. I will ask Mary if she knows about it. To date we have only found one land mammal. Some type of Palaeomerycid - type of deer. Similar to the one at BV Museum that Bob found only ours has 3 horns and only a partial skull and one bank of teeth.

The trespassers were identified but not arrested. I believe they were given a warning to keep out by the police. We now have security in place just in case. Also Rob is there a lot with all the quarry digs. It all helps. It seems like both slow curve and west quarry had nodules put aside, but not on whale quarry. It's a heck of thing to steal. They can be extremely heavy!! and I was told it takes a lot of prep work to get to the fossil inside.

Lisa

Hi Lisa,

Bob found a group of bones from a Merychippus-like horse in the whale quarry. I believe Bob had paperwork what what he found there. Mary might have that.

I think the stolen nodule was from the west quarry but not sure.

Were the trespassers identified and/or ever arrested?

Jess

[fossil26]

Rich,

If it was a short drive down the dirt road it probably was slow curve. A longer drive would have been West quarry. I just went back and checked out the photos you posted and I think

I saw a metal shed in the backround which means it's slow curve quarry. It's a shame that it was taken. Did you know what kind of skeleton it contained ?

Lisa

Lisa and Jess, I do not know which quarry I worled in with Bob - he didn't refer to it by a name. But the nodule sat right at the entrance to the quarry, beside his access road.

[RichW9090]

It was a pinniped, but not any of the larger ones like Allodesmus - I was thinking it might be the small pinniped that Bob had a few pieces from - a lower jaw in the BV museum.

[gwbh]

wow, you've found some cool stuff

[Boesse]

The problem with the turbidity current hypothesis is that it doesn't explain the sedimentology or the orientation of the skeletal elements. Turbidity currents produce predictable fining upward successions called bouma cycles or bouma sequences; classic 'turbidites' don't really match the vertical succession of lithologies, and the pervasive bioturbation at the bonebed and siltstone-mudstone contact below the bonebed suggests a prolonged period of exposure and biogenic reworking of sediment rather than an instantaneous event involving (geologically) simultaneous incision of the sediment and deposition of a fining-upward section of coarser sediment above, with coarse material at the very base. Regarding the taphonomic evidence, bones (just like coarse clasts in a turbidite) should be expected to be found at the sole of the bed, and additionally should be size-sorted - largest at the bottom, smallest at the top. Instead, there really isn't any evidence of size sorting, and bones and teeth of all sizes are jumbled into a relatively thin layer. Granted, Pyenson et al. did not really give much detailed data regarding vertical changes in taphonomic character, but this is based on their figure and my own observations of the bonebed. The single biggest piece of evidence, from my perspective as a marine vertebrate taphonomist, which strongly argues against any sort of depositional 'event' hypothesis for the bonebed is the abundant skeletons preserved about 1-2 meters above the bed. Pyenson et al. argued (correctly in my view) that the presence of more complete specimens further up marks a return to quicker sedimentation, as per the Kidwell 1985 model for the genesis of bioclastic accumulations. This does not mean rapid sedimentation, as in an event; but perhaps less slow than the depositional hiatus that permitted the bonebed to form in the first place. In a turbidite, everything is going to be mixed together and deposited en masse, so to speak; there is not going to be an interval of time that allows gentle deposition to cover up partial/complete skeletons one meter above the bonebed. Assuming a turbidity current happened, these skeletons would either A) have to be already defleshed (in which case they would be disarticulated and dispersed) or whole carcasses, and I'm not sure what would happen to a carcass in a turbidity current. A further issue is the abundance of manganese oxide nodules, which have been interpreted by some as in situ, indicate a protracted period of time accrued during the formation of the bed (unless they are allochthonous, which is a possibility). Furthermore, there aren't any other strata above or below which have been interpreted as turbidites; turbidites most frequently occur in stacks, and not really as a one-off occurrence amongst shelf deposits.

Here's another problem: bone accumulations like this are not really "normal". The Sharktooth Hill Bonebed is so large that it appeared to be on a shelf-wide scale, or at least a sizeable part of the shelf (it's an inland sea, but in terms of geographic scale). These concentrations of bones today are only really found on the seafloor in places of submarine erosion and upwelling. Normally, bones are far outdeposited by sediment; areas of moderate or rapid sedimentation have fewer bones per unit of rock, while areas of slow, zero, or negative sedimentation (negative = erosion) have higher concentrations of bones. Basically, in order to get an extreme concentration of bones and teeth like this - and here's the kicker - over such a large area on the shelf - you need something shelf-wide in scale that involves sediment starvation.

What about turbidity currents? Turbidity currents and other types of mass movement of sediment do not winnow or concentrate sediment (there will be some vertical mixing, to be sure - such as size sorting/grading). Turbidity currents take a large unit of sediment and transport it en masse from point A to point B, usually on a submarine fan, but it's not unheard of on the continental shelf. Basically that means the bioclastic component is not being separated out from the rest of the sediment - most modern interpretations of marine bonebed formation invoke changes in sediment supply and bypass, leaving the coarse fraction behind as a lag, with the fine fraction being transported further afield. Such processes occur across all the shelf at once, during changes in sea level. Which brings me to my last point: turbidites aren't particularly laterally extensive. They can extend over several km, and I'm sure on the larger submarine fans the active depositional lobe can be quite large (but such a situation would be uncommon in a confined area like the temblor sea). You can usually pick out in outcrop where turbidites pinch out laterally, and in turbidites under a meter thick they are often outcrop-scale in lateral extent.

Some further reading:

http://palaios.sepmonline.org/content/24/9/603.abstract

This is perhaps the one marine vertebrate assemblage which I think has been convincingly attributed to turbidity currents.

[nickkcin11]

Does anyone know if there is a public place near Bakersfield/Sharktooth Hill that one could still collect at? A location that is free and where it is legal to collect? I'll probably pay to go to the Ernst Quarry eventually, but for now I'm looking for an alternative (because you have to reserve a spot months in advance to go to the Quarry).

[Auspex]

Looks like the public dig schedule at Ernst Quarries doesn't start up again until the weather cools down in September. <LINK>

My understanding is that summertime heat there can be brutal.

[nickkcin11]

Are those public digs free but the paid ones go somewhere more lucrative? If there are just areas where one can go without a group or reservation, that'd be awesome.

[Auspex]

It may be a labor of love, but property taxes & etc. need to be paid, so all their digs come at a (reasonable, IMHO) price. As far as I know, there is nothing like it anymore that can be dug for free (without resorting to criminal trespass).

[nickkcin11]

I totally understand why they charge, museum fundings have been cut so it's only fair they charge. I'd rather they charge and allow people to collect than for the entire site to just close. Thank you for the clarification.

[siteseer]

PRK,

I think that's a Carcharodon (Isurus) planus anterior (flatter crown than hastalis). It could be from a file that was crowded by adjacent files while it was forming. I've seen a similarly shaped great white tooth.

Jess

A pathological puzzle
Just can't seem to ID this guy

[siteseer]

You could check out roadcuts in the area but you'd also have to look into the legality of that. Even if it's legal, the sheriff might ask you to move along because you're a distraction and it might be dangerous for you. Roadcuts wouldn't be nearly as productive as going to one of the quarries anyway. There's a reason even locals are happy to pay because just about all the other land is private and those landowners don't allow collecting.

I see it was only 98 degrees Fahrenheit in Bakersfield today. That's about what it will be into September.

Are those public digs free but the paid ones go somewhere more lucrative? If there are just areas where one can go without a group or reservation, that'd be awesome.

[FossilForKids]

Inyo

I think you are refering to stories in stone in Angels Camp and the land owner was Russ Schomaker. Her does have an incredible collection. He owned some of the Ernst property in the late sixties and early seventies I believe.

[siteseer]

Hi John,

That means someone else must have owned the property between Shoemaker and Bob. I think Bob bought his first section of the property in the mid-late 80's.

Bob and I traded notes about previous generations of collectors. He knew Bruno Benson and a few of the other people who dug in the 50's and 60's. I've been told about the Andersens. There was an old newspaper article about them and one of the teeth is shown in "Shadows of the Sea." That collection was later sold.

Jess

Inyo

I think you are refering to stories in stone in Angels Camp and the land owner was Russ Schomaker. Her does have an incredible collection. He owned some of the Ernst property in the late sixties and early seventies I believe.

[FossilForKids]

Hi Jess

Russ has a collection in the back of his store that got me started with my initial infatuation with sharktooth hill. From the pictures he had I would definitely say her worked Slow Curve alot. He told me he sold his land to some company related to oil in some way.

PS I live in Ventura now so if you know any Southern California locations you might want to share or go collecting some time let me know

[Plantguy]

Hey Paul, missed this thread somehow. Lots of wonderful material! I kick myself for never making it down to that site while in Calif...thanks for showing us. Regards, Chris

[PRK]

BTW: what is Carcharodon (Isurus) planus?

[mrieder79]

Man those teeth! Oh the teeth! I love the ones in the matrix, and in such good condition. I would love to hunt shark tooth hill someday.

[siteseer]

PRK,

We get into the technicalities of nomenclature with this one. Louis Agassiz originally described Oxyrhina planus for teeth now informally called the "hooked-tooth mako." David Starr Jordan, one of the foremost ichthyologists of the early 20th century, recognized that Oxyrhina was a junior synonym of Isurus so the species became accepted as Isurus planus for several decades.

What is not clear is whether planus descended from Isurus hastalis or if they have a common ancestor. I. hastalis is known from the Early Miocene of the Chesapeake Bay area (Calvert Formation) but planus seems to suddenly appear in the Sharktooth Hill Bonebed without an occurrence in the slightly older Lower Round Mountain Silt or Olcese Sand. The teeth can look similar but planus has a flatter, more curved crown and more rounded root lobes.

In recent years the name Cosmopolitodus has been used for hastalis and planus because those species have been considered to be of a separate lineage from mako sharks (modern Isurus oxyrinchus and I. paucus plus the extinct species, I. desori and I retroflexus). This is complicated further by the fact that I. desori is often considered just an early form of I oxyrinchus not requiring a name change..

However, over the past few decades, there have been teeth collected that linked Isurus (Cosmopolitodus) hastalis with the modern great white shark, Carcharodon carcharias (teeth only partially serrated). A couple of years ago, a fossil jaw set with partially serrated teeth was described as a species of Carcharodon (C. hubbelli). Because the genus Carcharodon was named before Cosmopolitodus, all species referrable to Cosmopolitodus (hastalis, planus, and presumably some earlier forms) must be placed in Carcharodon now. I'm not explaining this fully but that's the bare bones. I should have put Cosmopolitodus in parentheses rather than isurus but many people still think of hastalis as a mako (hard to let go of a familiar name even among paleontologists)..

BTW: what is Carcharodon (Isurus) planus?

[Boesse]

Nice bulla. That looks like other bullae previously identified as "Tiphyocetus", but there are three or four other reasonable candidates.

[siteseer]

PRK,

That's a great specimen - nice prep. Just to let others know, you have to prep them very carefully because they chip/crack easily. I have one like yours with the interior matrix still there because I don't want to risk damaging it, essentially-complete ones being rare. My advice to anyone else thinking of prepping one is to use hand tools (dental picks) and harden the exterior with Butvar (or even just superglue) first. Do not use a scribe (too much vibration).

Jess

This is a 99%+complete whale earbone. Bullae the opposit side of the bullae in post #2, a completely different piece