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Hunting The Lower Permian Of Nsw.


kauffy

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Ok so I figured I would do a little bit of a write up and share a few photos for the fellow fossilforum members. It has been a long while since I have done one of these but having spent a little while exploring some lower Permian outcrops in NSW Australia. I figured there would be some general interest in the Permian strata on the South Coast of NSW, as well as in the Hunter Region north of Sydney.

The Hunter Valley- not a bad place to explore for the day!

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NOTE: I will include a bit of geology, in a hope to educate and inform, and hopefully not bore!

Lets start with todays endeavors shall we!

Despite a slight increase in available literature regarding the paleontology of the Sydney basin, much of my research takes me to old publications, where many locations are briefly mentioned with little more than an obscure name that may or may not be associated with a similar name of some small road, in the back country, off the beaten track in the middle of nowhere.

This, is how my day started.

After hearing the name "Cranky Corner" mentioned in regards to the infamous Eurydesma bivalve years ago, a recent article once more mentioned this name and sparked my interest... and with it, shed more light into what has been described as the Cranky Corner Basin. (Dalwood and Maitland group - lower Permian). Now with little more than a general idea of where this basin was sitting in within the New England Oregen (Carboniferous volcanics and sediments) I found a little road called "Cranky Corner Rd", (who would have thought!?) and set course to check it out.

I took a risk by adding an extra hour to my journey, and unfortunately no bivalves to be found anywhere. I scoured a large outcrop of sandy siltstone and followed the road until it hit private property.

The Siltstone Outcrop

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It is more than likely the Cranky Corner Sandstone, (correlated to the Allandale Formation, late Sakramarian in age (where the Eurydesma fossils occur) was more than likely exposed nearby within one of the private farm properties. The scenery was beautiful though, I decided to head on to locations where I knew the Allandale Formation outcropped.

Harpers Hill - Allandale

A little while down the road I hit Harper's Hill, a large outcrop that exposes two main facies. I am fairly familiar with this site and have an extensive collection of fossils from here but decided to have another quick look. (I will upload a bunch of photos as I Identify them). The upper sequence consists of several beds of grey, massive thickly bedded coarse-medium grained lithic sandstone. These rocks are where many people come to look for Eurydesma however the abundance of fossils is quite low. Notable in these rocks were many large Keenia gastropods.

Keenia weathered out of the hard sandstone:

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As I moved along the outcrop I hit the second facies which underlies the hard sandstone. It is, what I would call a course-medium sand, quite soft. Although I only spent a short time here I noted this facies to be most fossiliferous in the unit underlying the hard grey lithic sandstone. I saw abundant brachiopods and gastropods and have noted a variety of bivalves from here previously. It is also one of the few locations where I have found large connularids (again photos of the collection to come!)

Peruvispira : Small abundant gastropods pack this rock, unfortunately the preservation within this unit is not great as the rock is so soft. Thats not to say there arent some spectacular moulds and casts!

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See, Spiriferid moulds!

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I had a little encounter with a beautiful juvenile eastern brown snake (Pseudonaja textilis) hanging out on the rocks... I decided against stomping through the long grass across the rest of the outcrop in case I met his twin! As much as I would like to step on the worlds second most deadly snake, and headed to my favorite Eurydesma location.

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The "Secret Spot"

As much as many fossil enthusiasts know about the Allandale Eurydesma bed located on the train tracks just south of town, they also know that gaining access to collect is impossible due to heavy train traffic and associated risks, and the legalities of trespassing on private land. It was only by chance that I stumbled upon a small, seemingly insignificant outcrop of rocks just south of the railway on Old North Road years ago (oops not so secret anymore). That said she is a fickle friend, and you really have to work for the goods!

Notable here is a similar hard lithic grey sandstone facies similar to that seen at Harpers Hill. I would confidently say it correlates stratigraphically with the unit based on visual characteristics, however cannot be certain as Harper Hill is "apparently" higher in relation to local topography. With no real knowledge of the oreographic history I couldnt say for sure that it is an extension of the same layer, or a similarly deposited, stratigraphically lower bed. The rocks here are still part of the Allandale Formation (part of the Dalwood Group - early Cisuralian)

All that aside, this unit is probably no more that 1 meter in thickness (where visual, probably extends further into what appears to be a "weathered zone" above the hard resistant layers. In addition the concentration of fossils is notably higher (it is this which led me to find this outcrop when driving by I saw many white blobs in a dark rock!)

Lithic Sand, lots of Eurydesma

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From past experience trying to dig into the hard sandstone is impossible, and often the specimens do not "pop out", rather shatter with their surrounding matrix. The gold is found in more friable layers just above the grey sandstone in a browner laminated sand (note sparce but present rounded clasts in this layer, a more clast dominated conglomerate lies below the fossiliferous layer). I quarried out a little area and within a couple of hours found a few good specimens of bivalve, gastropod and one uncommon brachiopod. I will include a few photos now, more to come tomorrow as I identify and clean.

Chizzlin'

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A large bivalved Eurydesma cordatum

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Hope you enjoyed reading, there will be more "eye candy" tomorrow and I will probably do another write up with some images of the lower permian strata I explored on the south coast.

Cheers

Chris

"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

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Hi Chris, great to hear from you!

Very cool trip, and excellent write-up :)

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

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Great post and pictures. The way I crawl around and move rocks at sites in the US I would be in deep trouble in Australia. Too many critters that I wouldn't want to get tagged by. I've had multiple occasions where looking for micro teeth on my hands and knees with my face almost to the ground where I looked to the side and saw a snake almost at eye level. Luckily we don't have Eastern brown snakes in the US.

Marco Sr.

"Any day that you can fossil hunt is a great day."

My family fossil website     Some Of My Shark, Ray, Fish And Other Micros     My Extant Shark Jaw Collection

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Awesome stuff! I have to make it up to the hunter for a hunt :D looks like a great place and i've seen some amazing stuff come from there :D A weekend soon i reckon! Love to see all your finds for the trip! Will you be posting what you brought back?

Also the snake is a Demansia Psammophis common name : Yellow-Faced whip-snake. We breed them :) Beautiful snakes and lucky for you they are only midly venomous ( enough to give you an ouchy bite with some local swelling and aching for 20 minutes or so. They live in small groups in rocky outcrops as they are skink eaters with a maximum length of 1.1 meters. :)

Looking forward to some more photos!

Jace.

Sydney.

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Awesome stuff! I have to make it up to the hunter for a hunt :D looks like a great place and i've seen some amazing stuff come from there :D A weekend soon i reckon! Love to see all your finds for the trip! Will you be posting what you brought back?

Also the snake is a Demansia Psammophis common name : Yellow-Faced whip-snake. We breed them :) Beautiful snakes and lucky for you they are only midly venomous ( enough to give you an ouchy bite with some local swelling and aching for 20 minutes or so. They live in small groups in rocky outcrops as they are skink eaters with a maximum length of 1.1 meters. :)

Looking forward to some more photos!

Jace.

Sydney.

Well that makes me feel a bit more comfortable, thanks for the herp lesson! You may be able to answer this, I assumed that mid winter snakes hibernate? Or is it not so much a proper hibernation and more-so they just become less active?

Also Jace the hunter has many more rich Permian sites both marine invertebrates and fossil plant locations. A trip north is always worthwhile. South too for that matter!

Photos to come. Glad you guys enjoyed reading :)

"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

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Well that makes me feel a bit more comfortable, thanks for the herp lesson! You may be able to answer this, I assumed that mid winter snakes hibernate? Or is it not so much a proper hibernation and more-so they just become less active?

Also Jace the hunter has many more rich Permian sites both marine invertebrates and fossil plant locations. A trip north is always worthwhile. South too for that matter!

Photos to come. Glad you guys enjoyed reading :)

Woo that sounds almost like an offer to show me around if i come up? hahaha! Yeah i've had a few hunts south for marine fossils but i've heard the hunter is the best place in eastern nsw.

As for the hibernation. It depends on the species and their chosen food source. Whipsnakes tend to remain active in area's warm enough to enable the small skinks they feed on to stay active. If the lizards are out sun-baking, the whip-snakes will be too! :)

The further north you go, the shorter periods reptiles hibernate, until you get warm enough year-round temps to keep them and their food out and about all year round.

Looking forward to those pics!

Jace.

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Ok guys here are some photos, admittedly the majority of the fossils are far from impressive however as a keen paleontologist I try my best to obtain specimens which represent the complete diversity of fauna for each location.

I will start with some images of fossils found at the small roadcut on Old North Road.

DESMODONT BIVALVES:

Currently working on identifying these based on the more complete specimens which I have photographed below. ID based on anterior, posterior length and height relationships (as the molds show little external morphological characteristics ie. ornamentation).

For those interested, here is an extensive paper by B. Runnegar out of the University of Queensland on the Desmodont Bivalves of the Permian of NSW.

Most of the specimens are internal molds, they are abundant in the overlying laminated friable sand and are often preserved with an outer carbon film. For now, they will be labeled by number until I have a confident ID at which point I will update the post.

1) Length 620mm

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2a) Length 510mm

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2b) Beak structure

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3) Exposed valve length 430mm

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4a) Species of Myonia, length 500mm

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4b) Extensive inflation of the umbonal region

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5) Length 450mm

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6) Length of hinge to broken edge 470mm

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7) Length 380mm

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"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

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Eurydesma

These bivalves are the most prolific species within the Allandale Formation and are known from several other lower Permian locations in NSW, Tasmania and QLD. Characterized by a robust beak and extraordinary umbonal thickness they dominate the outcrop on Old North Road. While im fairly confident the majority, if not all of the specimens collected represent the species E. cordatum.

Whole bivalved specimens of E.cordatum

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Large 13cm Bivalve

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The length of the large hinge is 2cm, showing great variation in size. Population of young and old.

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"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

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Keenia ocula

Keenia gastropods are quite common at this location as well ranging from >1cm to upwards of 15cm in height. Below are a few examples as well as an unknown fossil which I believe may be an operculum. Any suggestions on what else it could be?

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Operculum?

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"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

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