Category: Birdlings Flat

June-July 2022 Fossicking Trip: 2) Birdlings Flat

Location of Birdlings Flat. Source: Google Maps.
From an information sign at the carpark. This shows the stretch of beach I walked today.
The thick fog meant I couldn’t see the Banks Peninsula cliffs until I got very close.
What I would have seen if the fog was not there.

Second beach visit on my South Island fossicking trip was Birdlings Flat. I arrived there at 9 a.m. on Thursday (23 June) in thick fog with the temperature below zero. I was aware that the mouth of the canal from Lake Forsyth/Wairewa had been dug out recently to flush out the lake. The last part of the canal follows a path under the Banks Peninsula cliffs (see photo above, second from left), so I walked over that way. At one point, looking back, I spotted a small seal pup struggling up the beach, maybe looking for a rest from the heavy swells.

Small seal pup struggling up the beach behind me.
Getting closer to the cliffs…
Birdlings Flat stones, mainly greywacke.
Looking down on the canal dug from Lake Forsyth/Wairewa. The sea had piled up stones to cut it off.
The view from down in the canal.
Turning around and looking at the stones thrown up by the sea to block the canal outlet.
More Birdlings Flat greywacke (mainly).

I spent 80 minutes on the beach – the fog kept the stones wet though the lack of sun made it hard to spot them. I didn’t find any agates (not unusual for me) but found some nice jaspers and quartzites.

Brecciated jasper.
Quartzite.
Another jasper.
Quartzite.
Quartzite.
Brecciated stone.
Quartzite.
Unknown.

Some background on Birdlings Flat for those who don’t know it can be found here in TumbleStoneTwo. Driving further south, my next stops for Thursday will be Timaru and Kakanui.

Waves at the foot of the cliffs.
The bridge over the canal, at the lake end.
Looking into the foggy distance.
TumbleStoneTwo webpage on Birdlings Flat.

A shortened version of this Post first appeared in the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”. The next Post in this Series is on my visit to Timaru South. A Series Index is here.

TS2 – BIRDLINGS FLAT: MY STONE FOSSICKING

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The author on Birdlings Flat, 2016.
Some of the first stones I collected from Birdlings Flat.
Birdlings Flat stones, including beach agates.
From the start, I loved finding yellow quartzites like this.

I first visited Birdlings Flat in May 2016. I have made a number of other visits since. The following are Posts on TumbleStone Blog describing those visits, listed in chronological order:

Return to BIRDLINGS FLAT

HOME – FOSSICKING BEACHES – BEACH STONES – TUMBLE-POLISHING

TS2 – BIRDLINGS FLAT: GEMSTONE & FOSSIL MUSEUM

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Birdlings Flat Gemstone and Fossil Museum.
Some of the beach agates on display.
Part of the petrified wood display.
Quartzites, Birdlings Flat Gemstone and Fossil Museum.

The Birdlings Flat Gemstone and Fossil Museum is located at the end of Hillview Road at Birdlings Flat. A yellow sign is placed at the end of the road whenever the Museum is open – entry is free.

Google Maps1
Location of Museum in Birdlings Flat. Source: Google Maps.

The Museum was started in February 2003 by Vince and Colleen Burke, containing many of the polished stones he has collected off Birdlings Flat beach for a number of decades. It also contains large colourful agates, most of them collected from different parts of Canterbury, as well as many fossils. The Museum has been for sale for a while, so there is no guarantee of its continued existence.

TumbleStone Blog Posts on Birdlings Flat Gemstone and Fossil Museum:

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HOME – FOSSICKING BEACHES – BEACH STONES – TUMBLE-POLISHING

TS2 – BIRDLINGS FLAT

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Birdlings Flat lies directly south of Christchurch. Source: Google Maps.
Birdlings Flat. Source: Google Maps.
Birdlings Flat circled in black, where Kaitorete Spit meets Banks Peninsula. Source: https://en.wikipedia.org/wiki/Kaitorete_Spit#/media/File:Aerial_view_Lake_Ellesmere_2.jpg.
Birdlings Flat beach, looking towards the cliffs of Banks Peninsula.

Birdlings Flat is a stone beach immediately south of Banks Peninsula, half-way up the east coast of the South Island. It is about 50 kilometres south of the city of Christchurch. Banks Peninsula is of volcanic origin but the Flat is located on the far eastern end of a large gravel spit called Kaitorete Spit. A good introduction is provided on GeoTrips. The beach at Birdlings Flat is perhaps the most well-known among stone fossickers in New Zealand, especially for small beach agates. But much care needs to be taken when fossicking close to the sea, the waves being strong and dangerous, especially close to the cliffs of Banks Peninsula. There are three pages (so far) on TumbleStone Two on Birdlings Flat – this one of introductory and general information, a second on the Gemstone and Fossil Museum, and a third on my stone fossicking there.

Posts on TumbleStone Blog which provide an Introduction to Birdlings Flat:

Other TumbleStoneTwo Pages on Birdlings Flat:

BIRDLINGS FLAT: GEMSTONE & FOSSIL MUSEUM

BIRDLINGS FLAT: MY STONE FOSSICKING

HOME – FOSSICKING BEACHES – BEACH STONES – TUMBLE-POLISHING – ABOUT ME

February-March 2022 Fossicking Trip: Stone of the Day #2, Kaitorete Spit Quartzite(?)

On the morning of Saturday 12 February, I visited part of Kaitorete Spit, about nine kilometres south of Birdlings Flat (thanks to Tracey and Ashley for putting me up for the night). I then continued my drive south, visiting Malcolm Luxton in Ashburton before reaching Timaru where I spent Saturday night.

I found Stone #2 on Kaitorete Spit, about nine kms south of Birdlings Flat. I think it may be a quartzite. It has an amazingly detailed and complex structure:

Stone #2

The other side of the stone is similar:

Other side of Stone #2.

Kaitorete Spit is a 25 kms long gravel barrier that cuts off Lake Ellesmere/Te Waihora from the sea. Birdlings Flat is located at the northern end of this Spit.

Banks Peninsula and Lake Ellesmere/Te Waihora. Source: https://www.google.co.nz/maps/@-43.7927664,172.4773058,62610m/data=!3m1!1e3
Kaitorete Spit. Source: https://www.google.co.nz/maps/@-43.8083775,172.5418505,15648m/data=!3m1!1e3
I went fossicking in this area on Kaitorete Spit. Source: https://www.google.co.nz/maps/@-43.8083775,172.5418505,15648m/data=!3m1!1e3

When driving to Birdlings Flat, you turn off State Highway 75 onto Bayleys Road but quickly turn onto Birdlings Flat Pit Road to head to the Flat. If you continue along Bayleys Road, you drive onto Kaitorete Spit. About eight or nine kms along Bayleys Road (half of it being gravel road), you turn left to gain access to the beach near an area managed by the Department of Conservation.

The beach access along Bayleys Road.
Alongside the beach access.
Looking back towards Birdlings Flat 8 or 9 kms away.
Kaitorete Spit beach stones.

Four of the other stones I found during my two hours on Kaitorete Spit this morning:

Small green quartzite
Maybe also a quartzite?
Jasper.
Quartzite.

The next Post in the Series, on Stone #3 from a Timaru beach, is here. The Index to all the Posts in the Series is here.

February-March 2022 Fossicking Trip: Stone of the Day #1, Birdlings Flat Banded Agate

For the last three years, I have taken a four-week fossicking trip to the South Island during the February-March period to find beach stones for tumble polishing. At this time, the beaches are no longer busy with people enjoying their summer holidays yet the weather is still likely to be mainly fine. I take about a week to make my way by car from Whanganui to Riverton, visiting some South Island east coast beaches on the way, such as Ward Beach, Timaru and Kakanui. I base myself for a couple of weeks at Riverton, visiting places like Gemstone Beach and Slope Point, before taking another week to visit east coast beaches on my return north.

This year, I left Whanganui on Thursday 10 February, crossing Cook Strait by ferry that afternoon. My first serious fossick was at Birdlings Flat the following day, Friday 11 February. I have not visited Birdlings Flat much lately, maybe only twice during the past two years. I arrived at 2 pm and spent a couple of hours walking from the car park to the sea and then northwards towards Banks Peninsula (and back). The most interesting stone I found was a small banded agate, Stone of the Day #1:

Stone #1.
With a torch behind the agate.

This stone has more white in it than previous banded agates I have found at Birdlings Flat (see for example the stone featured in the Monday 17 May 2021 entry in this Post) but its bands are well defined and it is a nicely smooth stone.

The other side of Stone #1
With a torch behind the stone.

The day was cloudy and dull, not good conditions for spotting agates. I saw only two others, non-banded. I picked up a small number of other stones, mainly jaspers and quartzites. There were very few people on the beach while I was there:

Birdlings Flat, from in front of the car park.
Closer to the northern end.
Getting closer to the cliff at the start of Banks Peninsula.

Some background about Birdlings Flat can be found here.

The next Post in the Series, on Stone #2 from Kaitorete Spit, is here. The Index to all the Posts in the Series is here.

“W” is for “Ward Beach Zoophycos” and “X” is for “X-Figures When Veins Cross in a Stone”

R is for Riverton Rocks Red Rock
S is for Slope Point Stone
T is for Timaru Today
U is for Unusual Variations of Trace Fossil Stones
V is for >>>>>>

The following are my Posts for “W” and “X” in the weekly alphabetical series of a Facebook Group I belong to, “New Zealand Lapidary, Rocks, Minerals, Fossils”. The first Posts in this Series can be found here. The Series Index is here.

“W” is for “Ward Beach Zoophycos” – This stone contains a trace fossil, called zoophycos, and similar stones can be found especially along the Kaikoura coast. As noted in “A Photographic Guide to Fossils of New Zealand”, Ward Beach is famous for this type of trace fossil stone, of which there many variations.

Zoophycos stone from Ward Beach.
Page 64 in “A Photographic Guide to Fossils of New Zealand”

Ward Beach is about six kilometres off the main road east from the small village of Ward in the Flaxbourne District, 82 kilometres north of Kaikoura and 45 kilometres south of Blenheim. The Flaxbourne River reaches the coast at Ward Beach, which is set among spectacular scenery – high hills with steep slopes and a coastline with interesting rock formations. The Ward Beach boulders (concretions) are not far from the car park (maybe 10 minutes’ walk north). The beach was uplifted by the 2016 Kaikoura earthquake, unveiling the boulders.

The car park is near the centre of this stretch of beach. The boulders are a bit further north along the beach.
My little red car can be seen in the car park here. Looking from the south.
Looking from the north.
The beach in front of the car park, at low tide.
Some of the Ward Beach boulders.
Ward Beach stones.
Ward Beach stones.
Another Ward Beach zoophycos stone.
Another Ward Beach zoophycos stone.

The best part of the beach for stones is immediately in front of the car park, though it can be steep as it gets closer to the water and the incoming waves can be dangerous.

“X” is for “X-Figures When Veins Cross in a Stone” – This tumble-polished Birdlings Flat quartzite contains many veins, some very fine, others less so. When veins cross, “X”s are discernable. I have highlighted two of the many in this stone.

Polished Birdlings Flat quartzite.

National Lockdown Number Two: Stone Seven

Stone Seven is a small tumble-polished dendritic stone found on Birdlings Flat, just south of Banks Peninsula in Canterbury, sometime over the past couple of years. I was initially attracted to its cream colour with the additional black and brown lines and patches. It was only when working with the close-up images for this Post that I noticed the tiny fine dendrites in the stone.

Side A.
Side B.
Side A close-up.

The word “dendrite” is from the Greek word for “tree”, referring to the branching character of dendrites. In geology, dendrites are thin, branching crystals, often of some variety of manganese oxide (or iron), that grow over a surface in a rock or mineral. They are found in cracks or along bedding planes. Dendrites often look like fossil plant leaves but are, in fact, mineral crystals that form along a weakness in the rock as moisture moves through it. The brown dendrites in this stone, that have formed along fine black-coloured cracks, are not as sharp and clear as they often are in a stone, here appearing more fuzzy and diffuse.

On the seventh day of National Lockdown in New Zealand, daily cases of the delta Covid-19 variant were 41, having been 35 yesterday. That means there are currently 148 total cases in this outbreak. Daily cases should peak within the next three or four days, if the national strategy works. At present, the signs are good, with cases occurring in only two cities, 137 in Auckland and 11 in Wellington, although close contacts of cases are spread across the country. Eight people are in hospital with Covid-19, none in Intensive Care. Lots of testing is going on, contact tracing is proceeding, and the vaccination programme has sped up. Yesterday, the decision was made to extend the National Lockdown – Auckland will remain in Lockdown until at least the end of Tuesday 31 August (two weeks after the first case was identified) while the rest of the country will be in Lockdown until at least the end of Friday 27 August, with reviews to be undertaken just prior to these dates in the light of what happens in the outbreak.

Stone of the Day #8 is here.

Stone of the Week, Week One, is here.

“I” is for “Ichnogenus Protovirgularia” and “J” is for “(Picture) Jasper”

D is for Dendrites
E is for Entrance
F is for Fossil Worm Cast
G is for Green Hydrogrossular
H is for Hematite Jasper

A Facebook Group I belong to, “New Zealand Lapidary, Rocks, Minerals, Fossils”, invited its members to submit photos each week of a stone, mineral or fossil in their collection that starts with a letter of the alphabet. The first Posts in this Series can be found here. The following are my Posts for “I” and “J”.

“I” is for “Ichnogenus Protovirgularia”. This argillite stone from Gemstone Beach contains a trace fossil shape that has been identified by a trace fossil researcher as belonging to the Ichnogenus Protovirgularia.

A trace fossil is an “ichnofossil” – they are identified by their shapes (not by what made the shapes as this may not always be known). The term is derived from the Greek word “ichnites” meaning “footprint”. An “ichnogenus” is a group of trace fossils with similar characteristics (a “genus” is an intermediate category between “species” and “family”). Ichnogenus Protovirgularia are trace fossil shapes consisting of “a small keel-like trail which is composed of an elevated median line and lateral wedge-shaped appendages alternating on both sides”, including lines of chevron shapes (as in this stone I found on Gemstone Beach). They were given this name in 1850 by Frederick McCoy, an influential Irish palaeontologist, who believed he was seeing the actual fossil of an ancestor of Virgularia mirabilis, the slender sea-pen, hence the term “proto-virgularia”. It was not until 1958 that the shape was identified instead as a trace fossil (and one which was made by quite a different animal).

Some of the variations of Ichnogenus Protovirgularia. Source: http://www.researchgate.net/publication/240776411_Taphonomy_and_Paleoecology_of_the_Bivalve_Trace_Fossil_Protovirgularia_in_Deltaic_Heterolithic_Facies_of_the_Miocene_Chenque_Formation_Patagonia_Argentina
The coral spine of the slender sea-pen that McCoy thought that Protovirgularia was the fossil of. Source: https://v3.boldsystems.org/index.php/Taxbrowser_Taxonpage?taxid=726281&fbclid=IwAR2dh9plqzPHUVqTERF97moPqOsUHyV3-0PNsQ4OVmNziC6DXiivmGveGbA
How Seilacher thought Protovirgularia (on right) was produced. Diagram from his book “Trace Fossil Analysis” by Adolf Seilacher (2007), p. 65. However,, note that “Imbrichus” is also similar to the trace fossil on my stone.

It is thought that the trace is usually the product of locomotion (travel movement) produced by small bivalves, a burrow resulting from the rhythmic action of a muscular cleft-foot. On the southern coast, these traces are called worm-casts – it is thought that the casts were left as the worms tunnelled through mud and compacted the (excreted?) sediment behind them. It is not yet clear to me what left the trace on this Gemstone Beach stone, and I am not yet 100% convinced that this trace isn’t something other than Protovirgularia. More details on Ichnogenus Protovirgularia and trace fossil stones can be found here.

“J” is for “(Picture) Jasper” – Picture Jasper from Birdlings Flat.

Jasper is usually described as a form of cryptocrystalline silicon dioxide (quartz), as are a number of other rock types such as chalcedony, agate, carnelian, chrysoprase, chert and flint. “The Photographic Guide to Rocks & Minerals of NZ” defines “cryptocrystalline” as meaning crystals that are less than 0.001 mm in size, too tiny to see even using a hand lens. Jasper is distinguished by incorporating other materials that give it opacity (blocking the light) and colour. The Dorling Kindersley/Smithsonian book, “Rock and Gem”, states: “Brick-red to brownish-red jasper contains hematite; clay gives rise to a yellowish-white or grey, and goethite produces brown or yellow” (see scan of book page below). Names for types of jasper often refer to aspects of their structure or composition – banded, orbicular, moss, brecciated, or jasp-agate. But sometimes names relate to surface appearance and patterns – mottled, spider-web, egg pattern, and picture. Patti Polk, in her book “Collecting Rocks, Gems and Minerals”, defines picture jasper as containing “a dazzling array of colors and exquisitely detailed patterns that resemble skies, mountain vistas, desert landscapes, and forest horizons”. She also refers to “warm tones of tan, gold, yellow, blue, green, and browns all swirled together in strikingly outlined picturesque scenes”.

John Farndon and Steve Parker (2015) “The Illustrated Encyclopedia of Minerals, Rocks & Fossils of the World” p.213
https://teara.govt.nz/en/interactive/5123/chert-flint-and-jasper?fbclid=IwAR11CPAUP8DLyh6UMBXxTgoidS9AdL-ZCxZsXP0_L-nNLJeec8rYARHvQSw
Ronald L. Bonewitz (2015) “Rock and Gem” p.229
Patti Polk (2016) “Collecting Rocks, Gems and Minerals” p.123

I found this small picture jasper on Birdlings Flat about three years ago. Its pastel tones, the contrasts between light and dark, and the way a number of small cracks and fault-lines break up the surface pattern all contribute to its desert-canyon-landscape-picture. [This stone was Stone Eight in the Lockdown Stones of the Day Series.]

For the next Post in this Alphabetical Series, see here. You can find the Index for the Series here.

FB Group Posts: 5, 6 & 7 June 2021 – Birdlings Flat Stone, Timaru and Moeraki Village Fossicking

This is the eleventh Post in this Series of my daily Posts in the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”. The first Post in this Series is here.

Saturday 5 June 2021: Tumble-polished stone found on Birdlings Flat sometime over the last couple of years.

Other side of stone.

Sunday 6 June 2021: Three finds from my time on a beach just south of Timaru this morning. I am on my way south again to restock my beach stones for tumble polishing. My very first visit to this beach was yesterday, I just had to go back today, as there are some beautiful quartzites there. I also saw three seals. Right at the end, I came across a tiny fish (about 4 cms long) gasping for breath a couple of metres up the beach from the waveline – I carefully returned it to the sea.

I found a few green quartzites.
I’m hoping I can tumble this one in my 12lb barrel.
The beach just south of Timaru. I suspect recent stormy days have piled up more stones than usual – or at least given them a big stir.
The tiny fish I returned to the sea.

Monday 7 June 2021: Five small stones from my visit this morning to a beach near Moeraki Village, North Otago. Close inspection of each revealed fascinating details. Most are chalcedony (agate). The first three stones:

Stone 1 – small agate with “fortifications”.
Stone 1 held up to the light.
Stone 2 – orbicular chalcedony?
Stone 3 – another small agate.

It was difficult to see the details of these small stones before working with the photos. On the beach, I could often just see a hint of something interesting going on. Here is a photo of the beach, followed by photos of the other two stones:

The small beach near Moeraki Village.
Stone 4 – likely also to be chalcedony of some kind, maybe dendritic.
Stone 5 – conglomerate of some kind?

See here for the next Post in this Series.