Topic: Cliffs - Tongaporutu

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THE FOUR BROTHERS BEACH    Rock cliffs

The Four Brothers Beach extends from the Point south to the Gibbs’ Fishing Point.

From the Point down to the Pinocchio rock stack, the cliffs are highly fractured and composed of interbedded mudstones and sandstones.  The top layer consists of sand and volcanic ash.  The cliffs range in height from medium to high.  From Pinocchio down to the landward side of Cathedral Cave, the cliffs are somewhat smoother.  Close to the southern end of the beach, the cliff reduces in height.  It is bisected by a waterfall at its lowest point, around 30 feet above sea-level.  Also, this section of the cliff is particularly smooth.

There are several waterfall overflows on the 4BB, only one of which is associated with a highly active erosion site.  This is located at the rear of the Three Brothers.  The waterfall site to the rear of the oldest Brother is stable as is the one at the southern end of the 4BB.  The Four Brothers Beach also includes a horseshoe type cove to the rear of Pinocchio that I call Horseshoe Cove.  This a highly active erosion site.

The area between Pinocchio and the northern boundary of the Gibbs Fishing Point with Cathedral Cave at its base, is known as Mackenzies Bay.  On the 4BB there are several blind caves and arches, with the most spectacular of the arches being the Twin Arches.  They are located at one of the two major cave systems.  The Twin Arches cave has two entrances.  The north-western entrance has a huge, open bowl above it.  The other major cave is Cathedral Cave.  This is a 100 foot long blind cave.  It too has a north-western facing huge, open bowl above its main and only entrance.

There are five rock stacks, plus three defunct rock stack pedestals.  The rock stacks are, travelling from north to south.  The Oldest Brother, the three Brothers (collectively the Four Brothers) and Pinocchio.

2001

4.2.2001   PHO2008-832-834

I had yet to access the Four Brothers beach as I later came to call it.  The images here were taken from the Gibbs’ Fishing Point (also named later).  PHO2008-832 shows the southern part of the Four Brothers beach, along with the Pinocchio rock stack and three of the Four Brothers rock stacks.  PHO2008-833 shows the northern end of the beach with all four of the Four Brothers rock stacks.  The one out on its own is the Oldest Brother.  The Point is also clearly seen, with Elephant Rock on the Three Sisters beach immediately north (left in the photo) of the Point.  PHO2008-834 shows the cliff face that I later named the Wall. It is part of the Gibbs Fishing Point.  Like the Point, the Gibbs Fishing Point is a ‘separation point’.  It separates the Four Brothers beach, shown here on its northern boundary, from Beach One, on its southern boundary.

2002

27.4.2002   PHO2007-195

This image gives a closer view of the Four Brothers beach with its cliffs and rock stacks.  It also shows it during low tide.  I still hadn’t accessed the beach at this time.  The ship’s bow formation at the lower right is part of the Wall, itself part of the Gibbs’ Fishing Point.

2003

10.6.2003   PHO2008-908

This image was taken during the evening in the teeth of a roaring southerly.  The Four Brothers beach is well illuminated while the Wall is in shadow.

30.7.2003   PHO2008-088-089, 112-114, 980, 984

My first foray onto the Four Brothers beach.  I noted that significant erosion was taking place and I also observed huge boulder falls.  These were initial observations, not noting any recent cliff falls.  Aside from what I called the Four Brothers rock stacks, another magnificent feature was the Twin Arches.  These are located on the southern, external cliff wall of what I call the Twin Arches cave system.  The Twin Arches houses a large, through cave and this is covered more specifically in the section on Sea Caves.

13.8.2003   PHO2008-138-154, 164-165,168-170, 174, 179

CLIFF SEQUENCING.  Due to fine weather and a built up beach, I was able to do a full face-on, not angled, cliff sequencing.  That is, photographing the cliffs in sequencing as I walked down the beach at the wave-line.  The exception to this was at the beach section from Pinocchio down to Cathedral Cave, otherwise known as MacKenzies Bay.  The MacKenzies farm is immediately landward of the 4BB.

The unique land-form topography at MacKenzies Bay, including the Gibbs Fishing Point/ledge and Gull Rock, causes the sea and resultant waves to ‘bunch up’ or ‘ride higher’ than the rest of the 4BB.  The net effect is that the tide does not go out as far so this area is more dangerous.  Only once have I observed the opposite occur due to an unusual beach (sand level)  topography change.  This may have been due in part to a rare oceanic current fluctuation at this specific location.  (It will be mentioned later).

28.8.2003   PHO2008-187-189, 197-198, 1014-1015

A full cliff-face collapse occurred to the rear of the oldest Brother rock stack and just north of it.  I commented at the time that it looked like “a giant had taken a huge chomp out of it.”  (The cliff).  Judging by the freshness of the boulders and abundance of live flax present, not here, but on the Three Sisters Beach and across at Pilot Point, I guessed that it had occurred during the past 48 hours due to the relatively pristine state of the sea-tossed flax bushes.  That is, they had not been bashed about by the sea long enough to be shredded, especially as big seas were running with storm surge conditions and copious amounts of frothy sea-foam.

To the rear of the oldest Brother, there is an arch and immediately to its south, a stream constantly overflows from the top of the cliff.  Despite this, this site is remarkably stable, unlike the area to the rear of the other Brothers which is highly unstable in the presence of water.

I also took several other images, including one of all four of the Four Brothers rock stacks.  I have included this particular image here because this viewpoint is only possible from a very small area.  I wanted to show them in relation to the cliffs that gave birth to them.

6.9.2003   PHO2008-206, 1029, 1031

PHO2008-206 shows the cliffs and the Four Brothers under stormy conditions.  PHO2008-1029 was taken on a low point above the cliff where a small stream tumbled down onto the beach near Cathedral Cave.  PHO2008-1031 was taken from the same low cliff viewpoint, but looks across to the landward side of the Wall (part of Gibbs’ Fishing Point) that houses Cathedral Cave.  The cave’s entrance is in deep shadow to the left of the frame.

29.9.2003   PHO2008-1035

ALPHA STORM.  Though I didn’t access the Four Brothers Beach, I did observe from Gibbs’ Fishing Point that ONE OF THE FOUR BROTHERS rock stacks had been DESTROYED.  The photo, though only showing the Four Brothers Beach in the distance, with the Wall in the foreground, does show the extent of the wash zone.  The analogy being, the more powerful the storm, the further out to sea the wash zone extends.

6.10.2003   PHO2008-1049-1050

PHO2008-1049 shows the northern half of the beach with the surviving three of the Four Brothers.  The stump of the middle Brother, destroyed in the alpha storm of the 29th September, is clearly visible.  PHO2008-1050 was taken above Horseshoe Cove at the southern end of the beach.  I later called this the Picnic Table Overlook.  The viewpoint looks north and shows Pinocchio at lower left and the southern, main entrance of the Twin Arches cave system.  (See Section Five on Sea Caves).  The Twin Arches are also shown, but from this angle, they appear to partially merge into the cliff.

8.10.2003   PHO2008-255, 259, 271,1052,1054

PHO2008-271 shows the remains of the cliff collapse that I observed on the 28th August.  Photos PHO2008-259 and 1052 show the Brothers rock stacks in relation to their environment.  (See also Section Six on Rock Stacks).  Photos PHO2008-255 and 1054 show the Twin Arches.  In the latter image only one of the arches is visible.

24.11.2003   PHO2008-418, 421, 426

A full cliff face collapse had occurred to the rear and north of the innermost Brother rock stack.  No soil remained and I don’t mention any washed up plant material further down (north) the coast.  The rock pile is quite smashed up.  I estimate this collapse occurred within the past couple of weeks.  At the time I thought it was 24 hours, but I have learned a lot more as of June 2009.  PHO2008-418 shows the Twin Arches.

1.12.2003   PHO2008-443, 1126, 1127

This was the first time I accessed what I later called the Brothers Overlook.  It is situated on the MacKenzies farm.  It afforded spectacular views looking south from above the inner Brothers towards the Twin Arches and Cathedral Cave and Gull Rock in the distance.

3.12.2003   PHO2008-457, 460, 1132, 1134, 1137, 1141, 1146, 1148

I couldn’t wait to return to the newly discovered (for me) Brothers Overlook, even though the weather was wet.  Hoping to capture a variety of viewpoints I brought up several different lenses.  I also hoped that I might get some magic light later on, which I did.  Please note that PHO2008-457 was taken from above Horseshoe Cove at the Picnic Table Overlook, not from the Brothers Overlook.

26.12.2003   PHO2008-478-479, 486-487

I observed a partial cliff-face collapse between the Point and the oldest Brother.  Specifically, it was immediately south of a small rock pillar.  Further down the beach I observed a full cliff-face collapse that had occurred immediately south of the full cliff face collapse I observed on 24.11.03 to the rear and immediately south of the innermost Brother rock stack.  This latter one may have been triggered by a ‘ripple effect’ emanating from the close-by, earlier cliff collapse.  I do mention some beaten up flax bushes on the 3SB, indicating that the Brother cliff collapse possibly occurred during the past week.  The partial collapse near the rock pillar occurred within the past month.

At Horseshoe Cove I observed a huge crack or fault-line on the southern cliff-face.  (Closest to Pinocchio rock stack).  PHO2008-487 refers to this.

2004

4.1.2004   PHO2008-1177

I was staying up at the Gibbs for a few days.  One of the places I visited was the Brothers Overlook.  However, as it was bright sunshine, I only took a few images.

9.3.2004   PHO2008-1241

I photographed here in the pre-dawn light.  One thing I noticed is that sound is accentuated, or appears to be, when vision is impaired due to low light levels.  I therefore don’t know if it actually is noisier pre-dawn than daylight or not.  If so, then this could be a partial explanation why apparently more cliff falls occur at night than during the day.  The site of the first cliff collapse I documented to the rear of the inner Brother (24.11.03), was now clean.  No evidence of it at the base remained.  This is a particularly active, erosion area, due in part to the cutting effect of a stream.

It is interesting to note that not all overflowing streams have equal cutting effects.  In some places the cliffs are remarkably stable, despite the constant flow of water, while in others such as here, the cliffs are unstable.  The upper land topography and rock strata composition, especially with regards to compaction (density ratio), coupled with strategically aligned fault lines, make the cliff sites they are associated with, extremely vulnerable to the sluicing effects of water.

5.4.2004   PHO2007-205

The small rock pillar between the Point and the oldest Brother is still intact.

6.6.2004   PHO2008-1276

From the Picnic Table Overlook I observed a A cliff collapse at Horseshoe Cove.

1.8.2004   PHO2008-1326, 1328, 1329, 1332, 1333, 1334, 1343-1344

I took several images on this fascinating beach roday.  Some highlight its distinctive features.

2005

21.8.2005   PHO2008-1417-1418, 1428

The small rock pillar between the Point and the oldest Brother is still intact.  To the rear of the two Brothers, a large crack is visible in the cliff immediately north of the first cliff collapse site that occurred on 24.11.03.  This jutting piece of cliff leads immediately north into a large cliff indentation which is being eaten away by flowing water emanating from a swampy area on top that is a little further back from the terminating cliff-top.  I also photographed the The Twin Arches.

19.9.2005   PHO2008-1442, 1445 and PHO2010-0507

ALPHA STORM.  From the Picnic Table Overlook on the MacKenzies farm, I photographed huge waves slamming into the Wall, part of the Gibbs’ Fishing Point.  This is to the rear of Cathedral Cave which is on the Four Brothers Beach.  The cave’s entrance is fully visible.  What I didn’t notice at the time however, was that a large chunk of cliff wall, immediately to the landward side of Cathedral Cave had collapsed.  It was only when I got my photos back on 26.9.05 that I became aware of it.  (More information on this is in the Section on Sea Caves.)

30.11.2005   PHO2008-1517, 1518, 1519 and 1520

The small rock pillar situated between the Point and the oldest Brother has been destroyed.  (PHO2008-1518).  There had also been a partial cliff collapse.  Just north and to the rear of the oldest Brother, there had been a full cliff-face collapse.  It is in a similar position to the cliff collapse I noted on 26.12.04, if not the same position.  If the same position, then the cliff collapse site has been greatly extended.  There was a large amount of surviving debris that included soil and large boulders.  As I didn’t note any plant material washed up on the 3SB, I assumed it to have occurred during the past month.  Another possibility is that it could have been caused by the alpha storm I recorded on 19.9.05.

To the rear of the Two Brothers, the large crack in the cliff I photographed on 21.8.05 had disappeared, along with the slice of cliff it had supported.

2006

15.1.2006   PHO2008-1546-1548, 1550-1553

A rock fall had occurred at the landward end of Horseshoe Cove.  I observed this from the top of the cliff.  Walking around to a different viewpoint, I noticed a chunk of cliff that had fallen off in the past revealed the petrified (calcified?) remains of a past forest.  It appeared around 20 feet below the surface layers.  The forest was perhaps destroyed by ash from a past Mt Taranaki eruption.  (See also Section Three on Rock Strata).  I also photographed the cliff leading around to Cathedral Cave.

Down on the beach I re-photographed some of the cliffs that I had photographed on 30.11.2005.

31.1.2006   PHO2008-1569, 1571, 1574

Whilst being filmed by Sticky Pictures for the upcoming Earth, Wind and Fire exhibition being put on be the Te Papa Museum, Wellington, I had the chance to do some aerial photography.  Unfortunately, due to the light, they are not tack sharp.  PHO2008-1569 looks down on Horseshoe Cove.  PHO2008-1571 looks down towards Cathedral Cave at the southern end of the Four Brothers Beach.  Lastly, PHO2008-1574 looks north along the beach.  The large rock stack out on its on is the Oldest Brother, while the two close together are the two youngest Brothers.

1.3.2006   PHO2008-1576, 1579 and 1589

At Cathedral Cave, the chunk of missing cliff face that had been sheared off during the alpha storm of 19.9.05 was huge.  The remaining cliff face looked really fragile.  And so it proved.  Small rock shards and rocklets were shaving off the cliff face on a regular basis.  I sat down to scoff my date scone and have a guzzle of water when some cliff fragments came down, thwacked into a pool and splooshed me with water.  I quickly got the message.  Though PHO20080-1589 primarily shows the Wall which is part of the Gibbs’ Fishing Point, I have included this image because it it shows the ship’s bulb feature which leads around to Cathedral Cave on the left.  Cathedral Cave is for my purposes, part of the Four Brothers Beach.

30.3.2006   PHO2008-1603

The cliff bases to the rear of the Two Brothers (the twin cliff collapse sites) were completely clean of any debris.  More cliff material had shaved off the cliff next to Cathedral Cave.  The photo here is just a standard shot showing the southern end of the beach.

17.5.2006

Above Horseshoe Cove I noticed a large chunk of cliff, literally the bottom half on the northern side had collapsed quite recently.  There was still live vegetation at the bottom and a large rock debris field.  I didn’t photograph it as I didn’t have my camera on me!

13.6.2006

I finally photographed the cliff collapse that occurred at Horseshoe Cove last month.  Rocks were still present at the cliff base.  However, due to a stuff up on my part, I opened up the camera back before it had wound right back.

20.6.2006   PHO2008-1635, 1926, 1935

I had been waiting for a clear day like this because I wanted to photograph the cliffs in winter evening light.  The best spot was from the Brothers Overlook with White Cliffs and Mt Egmont in the background.  I also photographed looking towards Cathedral Cave from the Picnic Table Overlook.

26.7.2006   PHO2008-816, 1960, 1963-1967 and 1973

Photographed the cliff collapse site at Horseshoe Cove close up.  I photographed the Twin Arches.  They appear to be quite stable thus far.  Quite the opposite can be said for the Twin Arches cave system to their rear.  It was a magnificent day for photography and I made the most of it.  You can’t beat winter light.  PHO2008-816 is one of my favourite images.

10.8.2006   PHO2008-1982-1983, 1986-1989

I documented the rapidly indenting cliff to the immediate rear and north of the Two Brothers.  I have photographed from the top of the cliff here looking down on the southern part of the 4BB.  It now appears to be unsafe to access.  I also documented two ‘open mouth’ orifices that were forming in the lower part of an outward jutting part of the cliff close to the southern entrance to the Twin Arches cave.  Specifically, the northern cliff wall of Horseshoe Cove.  See PHO2008-1986.  (I later called this particular rock the Fractal Rock.  See also Section Three on Rock Strata).

Other things photographed included a small internal ledge, the Twin Arches and down near Cathedral Cave.

9.9.2006   PHO2008-1996

Steady rain was falling but there was no wind.  This waterfall feature and through going arch are located to the rear of the Oldest Brother.  There is a forming cave to the rear but I haven’t paid too much attention to this.

2007

15.7.2007   PHO2011-1015-1016, 1020

There had been a partial cliff collapse at Horseshoe Cove.  At the Twin Arches, I observed that the inner arch has a large crack going up its centre, and the outer arch has definitely thinned at a critical point at the top of its pedestal and the cliff part connected to it.  (Different rock strata).

When I began to return along the 4BB, I was gobsmacked to see a massive full cliff-face collapse to the rear and immediately north of the inner Brother.  This part indents landward quite sharply in like a small ‘V’ shaped bay.  I didn’t see it about an hour earlier.  Then I thought back to the loud noise I had heard while changing my roll of film. (Out of line of sight).  This collapse had occurred while I was on the beach at the time.  What made it scarier was that this is the site of the cliff-top lookout that I have previously photographed from.  Huge, fresh grey boulders littered the beach and lots of tiny grey fragments pocked the sand.  Further up the cliff face were earth and live plant debris.

5.8.2007   PHO2011-1026

My viewpoint was above Horseshoe Cove.  A chunk of cliff had collapsed immediately to the rear of the Fractal Rock.  This exposed a small blind evolving cave close to the southern side, but separate from the Twin Arches cave system.  This was a different cliff failure to the one documented on 15.7.07.  As most of it had been sluiced away, I assumed it had occurred within the last two weeks.  It could be fresher as the sea state was amped up with furious white horses charging landwards.

27.9.2007   PHO2011-1066

Above Horseshoe Cove.  There had now been another cliff collapse to the rear of the Fractal Rock to that observed on 5.8.07.  This one was however a full cliff-face collapse, and the forming small blind cave is now completely destroyed.  This appeared to be quite fresh with a large amount of soil and boulders still intact at the base of the collapse site.

23.12.2007   PHO2011-1132-1134, 1136, 1142, 1145

There had been a partial cliff collapse immediately next to the south- western entrance of the Twin Arches cave.  I estimated it had occurred during the past 48 hours...  Some silly people wandered out from the cave and over the fallen rocks, oblivious to the danger of cliff collapses.  Just as I had been on my first visit at Pilot Point Cave back in April 2003!  Between Pinocchio and Cathedral Cave at Mackenzies Bay, I noticed a large rock debris field from a recent partial cliff-face collapse at the base of an inverted cliff face which housed a blind cave on its northern side.  Like the debris field at the rear of the Twin Arches cave, this appeared to be quite recent.  At Cathedral Cave, a large rock debris field was evident.  Large boulders here tend to live a while from past cliff collapses.

2008

23.1.2008   PHO2011-1148

This view looks north towards the Twin Arches.

10.2.2008   PHO2011-1174-1175

Apart from one cannon-ball type rock, all of the cliff collapse debris that I had observed on 23.12.07 had vanished.  Some could have been buried by sand, but nothing was visible save for this single rock.  At Horseshoe Cove I photographed the cliff collapse debris field at the base of the destroyed forming blind cave.  I first noted this on 27.9.07.  Of the cliff collapse that I saw at MacKenzies Bay on 23.12.08, nothing remained.

6.4.2008   PHO2011-1203

In the V inlet immediately to the north and rear of the inner Brother, a small, fresh rock fall was evident.  This site is highly active erosionally.  I was also taken with a Giant’s Foot type cliff formation just north of the Oldest Brother.

 

 

6.5.2008   PHO2011-1228, 1230-1231,

 

The weather was fantastic.  Perfect for visiting Tongaporutu.  At perfect day at the office!  No cliff collapses were observed.

 

 

28.9.2008   PHO2011-1328,1330, 1332

 

A partial cliff collapse was observed on the northern cliff section protruding out from the V inlet to the immediate north and rear of the inner Brother.  I estimated that the collapse had occurred within the past 48 hours due to none of the material yet having rounded edges caused by wave/sand friction.  However, the real biggie had occurred at the Twin Arches cave system at the northern main entrance.  Here, the whole cliff bowl shaped roof had totally collapsed.  I assumed this collapse had occurred during the July Super-storm event that had caused so much destruction on the 3SB and destroyed the Pilot Point arch.  Due to the gargantuan amount of debris, I couldn’t tell if the beautiful central arch had been destroyed or not.

 

 

15.10.2008   PHO2011-1358-1360

 

The cliff collapse material to the north and rear of the inner Brother was in the process of fanning out and being smashed up.  The huge debris field at the Twin Arches cave entrance remained largely intact.  This used to be a through cave but this entrance is now effectively sealed.  Until enough rain has sluiced it away, combined with wave action, further cave evolution will be fairly static.  Only when waves finally breach the debris field to make it a through cave again will erosion speed up.  When I exited the mostly intact cave (from its undamaged southern entrance, a small shower of soil debris rained down on the opposite side to me.

 

 

14.12.2008   PHO2011-1443, 1445-1459, 1461-1464, 1466

 

CLIFF SEQUENCING.  The Twin Arches cliff debris still continues to only slowly sluice away.  Aside from this, the sequencing was quite uneventful.  No fresh cliff collapses were observed.

 

 

 

2009

 

 

11.1.2009   PHO2011-1495-1496, 1499,

I photographed a section of the 4BB cliffs looking north from the rear of the inner Brother towards the Point.  This was done to show how the caves and arches are predominantly carved out from right to left (south to north), due to the prevailing sea/wind direction from the south-west, combined with the angle of hit (70-75 degrees).  At the Twin Arches, the cliff debris is still slowly washing away.  A view to the sky is visible from inside the cave as the entire cliff roof dome collapsed in July 2008.  To the immediate left (north) of the Twin Arches there is a large fracture line running semi-diagonally up the exterior cliff/cave wall.  This may have been affected by the roof collapse and loss of some upper seaward side external cliff wall material.  The magnificent Twin Arches themselves are now in danger.

8.2.2009   PHO2011-1571

At the Twin Arches cave collapse site there appeared to be little change in the debris field.  It is still massive.  The large crack in the exterior cliff wall is evolving and there are several other cracks present too.  A large chunk of this cliff will collapse in the not too distant future leaving the Twin Arches themselves highly vulnerable.

25.5.2009   PHO2011-1598-1599

The debris field at the base of the cliff to the north and rear of the inner Brother was still there.  It also appeared as if more material had come down, but not recently.  At the Twin Arches cave collapse site, the huge debris field had lost a lot more of its mass and the hole to the sky was clearly visible.  At the base of the debris field I felt I could climb up to its lowest point above the beach and see inside the cave.  That is if the material was firm enough to stand on.  The mostly grey mudstone had the consistency of firm but slightly sticky concrete.  This provided a firm, waterproof barrier at present to through waves.  And could explain why it is taking so long for this material to be broken up.

On top of the rubbish heap, the bowl shaped roof had completely gone.  Also destroyed was the beautiful central arch, or Giant’s Foot as I had called it.  One of the cave’s internal blind corridors was jammed with cliff fall material, but as a whole, the cave proper remained remarkably intact.

 

22.8.2009   PHO2011-1643-1644, 1649-1650, 1654

I observed three recent cliff collapses on the Four Brothers beach today.  The FIRST was in the usual spot to the immediate north and to the rear of the Three Brothers .  A large boulder roughly the size of a small car was there, plus a few other rocks.  I couldn’t accurately size or date it, but assumed the debris to be reasonably fresh as the large boulder was still intact despite the king tides.

At the Twin Arches cave collapse site, all of the cement-like material had gone, apart from a layer on the floor.  The cave was once again a through cave.  Of the Giant’s Foot column, only its pedestal, now clearly visible, survived.

The secomd cliff collapse I noticed was at Horseshoe Cove to the rear of Pinocchio.  Judging by the material, I estimated that it had occurred during the past week as much of the material, largers rocks etc., was relatively intact.  I judged it to have been a three quarters cliff face collapse.  While photographing from atop the debris pile, some rock shavings splattered around me, but I was untouched.  I was closer to the cliff face than I liked.  One thing that I did notice was a wavy scallop type pattern etched into the face of a split rock.  I thought it might have been a fossil.  It was about a foot in diameter.  I photographed this, then got away from the site as quickly as possible.  (I later discovered that it was a body fossil of a sabellid (polychaete annelid) worm.  Specifically, Amuri Zoophycos.)

The third cliff collapse occurred immediately south and to the rear of the Three Brothers.  This area is an erosional hot spot.  I hadn’t noticed it coming down the beach because it is partially obscured from the north.  It is preferentially carved out from the southern (right to left, or south to north) side.  It was around a three quarters cliff face collapse.  Once again I couldn’t accurately date it, but believed it to have occurred during the past week in tandem with the king tides.

19.9.2009   PHO2011-1906

I didn’t observe any fresh cliff falls.  The cliff collapse that had occurred to the rear of Pinocchio in Horseshoe Cove (observed on 22.8.09), had been smashed up more.  I couldn’t find the rock that had the scallop type pattern on it.  Must have either been smashed up or smoothed off by wave action.

At the Puke Ariki Research centre on 24.9.2009, via Ron Lambert and Gary Bastin, I discovered that the scallop type pattern on the rock belonged to Amuri Zoophycos, a sabellid (polychaete annelid) worm.  Specifically, it is the worm’s fossilized complicated burrow system that is composed of a coiled spreite, which contains arcuate, radiating ribs (major lamellae), and feathery filaments (minor lamellae), between ribs.  (See Ichnos, v, p. 183-194, 1991.)

 

2010

 

30.1.2010   PHO2011-1723, 1727

 

At the Twin Arches cave, all of the debris field has gone.  At Horseshoe Cove, there appeared to have been a fairly recent partial cliff-face collapse.  It appears to have originated at roughly the same place as the much larger cliff collapse that I observed on 22.8.09.

28.3.2010   PHO2011-1953

(Digital camera).  At Horseshoe Cove there had been a partial cliff collapse close to one I observed on 30.1.2010.  Some material from the large cliff collapse I observed on 22.8.2009 is still present.  The majority of the cliff collapses at Horseshoe Cove occur at the rear of the cove.  This is a highly active erosional hotspot.

31.3.2010   PHO2011-1793, 1795

Today I came up with my panoramic camera as I wanted to record the Three Sisters Beach (which didn’t happen) and the Four Brothers Beach.  Specifically I am hoping to record all of the main beaches with the panoramic camera before the project finishes in June of this year.

I was hoping to get great evening light on the cliffs.  A very low 0.1m tide was due at 5.41 pm and the beach state was very good.  Unfortunately, the sun didn’t play ball as it was frequently hidden by slab cloud.  I did get a photo looking north along the beach that included the Twin Arches, cliffs and the Brothers.  Unfortunately, only the Twin Arches were well illuminated.  I did get a better photo down at the Cathedral Cave area of the beach.  In particular I got a nice image of the green framed waterfall that spilled over a low cliff wall just before you arrived at Cathedral Cave.  The cherry on top was a friendly, lone herring gull that was parked on the beach immediately below the waterfall.  When I say ‘waterfall’, due to the dry weather conditions, it was more of a water seep or water trickle.

11.7.2010   PHO2011-1814-1816

The weather was fantastic with Mackenzie Country type clarity.  Below the Brothers Overlook, (an erosion hotspot), there appeared to have been a partial cliff collapse.  As the depleted debris field was spread out towards the Inner Brother, I concluded that it had occurred at least a month ago.

Down at Horseshoe Cove, there had been a relatively fresh full cliff-face collapse.  This had occurred on the southern side of the cove.  The rocks were unweathered and there was a substantial amount of soil on top of them.  I estimated that this had occurred during the past couple of weeks, probably less.

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