Lake Rotomahana, New Zealand: Once were Travertine Terraces

Coastal geology & environment, Environmental, Geography, Natural Environment, Regional History, Science and society

There’s only a handful of natural travertine rock formations𝔞 in the entire world, but after 1886 there was was one less. In that year in New Zealand’s Rotorua/Bay of Plenty area, the terraced hot springs wonderland known to Pākehā New Zealanders as the “Pink and White Terraces”𝔟 (Ōtukapuarangi and Te Tarata) were obliterated from sight in a massive eruption from nearby Mt Tarawera (Māori: “burnt spear/peaks”)𝔠.

🌋 Charles Blomfield’s painting of the volcanic occurrence

Fallout from the volcano’s eruption blanketed some 15,000 sq kms of countryside with ash in the air travelling as far away as Christchurch, over 800 km to the south. The explosion of volcanic craters reduced Lake Rotomahana (“warm lake”) to mud and ash. The deafening noise and lightning of the dome volcano exploding caused some in Auckland to think that Russian warships were attacking the city [‘The Night Tarawera awoke’, New Zealand Geo, www.nzgeo.com]. The human casualties were almost all Māori, about 120 people died, as well as 10 Māori settlements destroyed or buried.

Blomfield’s painting of Te Tarata

19th century tourist attraction
Nature’s violent removal of the Rotomahana travertines brought an abrupt end to a lucrative little 19th century tourism earner for the local region. Artist Charles Blomfield who painted the two terraces on multiple occasions was an eye witness to the tourist boom, observing groups of “moneyed people” bathing in the hot springs𝔡 while their lunches of potatoes and koura were cooking in the boiling pools (NZ Geo)𝔢. Village residents benefitted—some Māori guides netted incomes of up to £4,000 a year—but the First Nation community also copped the downside from the economic boost, rising illness and rampant alcoholism [‘Tarawera Te Maunga Tapu’, Rotorua Museum, www.rotoruamuseum.co.nz].

Lost and found?
For 120 years New Zealanders thought that all trace of the iconic terraces—the two largest known formations of silica sinter on earth—had vanished. Scientific curiosity in recent decades has speculated whether the terraces has been destroyed altogether or perhaps permanently entombed. Recently, Geologists, drawing on Ferdinand von Hochstetter’s 1859 topographic and geological survey of Lake Rotomahana as a primary source, believe they have found traces of the lost White Terraces in the naturally-restored, crater-enlarged lake [‘A natural wonder lost to a volcano has been rediscovered’, Robin Wylie, BBC, 28-Apr -2016, www.bbc.com]. The terraces are thought submerged under sediment and 50-60 m of lake water.

🔻 1860 lithograph of Hochstetter talking to the Māori rangatira of the White Terraces

New Zealand’s miniature ‘Pompeii’
Right in the firing line of Mt Tarawera when it exploded in 1886 was the tiny village of Te Wairoa and its inhabitants the Tuhourangi people. Engulfed and obliterated by the eruption, it became known as the “Buried Village” of Te Wairoa. These days it has brought back tourism to the area. The excavated village is New Zealand’s most popular archaeological site.

(Source: Flickr.com)

Postscript: the Rotomahana travertines are destroyed but is at least one terraced hydro-thermal springs in the North Island remains. Wairakei Terraces, situated 90 km south of Tarawera in Taupō, is a smaller version of the Pink and White Terraces. This commercial operation is a combination of the synthetic (man-made geyser) and the natural (pink, blue and white silica steps).

🔻Pamukkale, Turkey

🌋 one of the most outstanding examples of travertine formations on the planet is the “Cotton Castle” of Pamukkale in eastern Turkey, with its glistening white-terraced geo-thermal springs sharing the site with the ruins of a Greco-Roman city Hierapolis, making it a world-class tourist magnet. Other extant travertines include Badab-e-Surt in Iran, Mammoth Hot Springs in Wyoming, USA, and Egerszalok in Hungary.

Pink Terraces (Photo: Charles Spencer/ Te Papa)

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𝔞 travertines are formations of terrestrial limestone and calcium carbonate deposits around mineral (especially hot) springs, which are often terraced  

𝔟 their names in the Māori tongue translate respectively as “fountain of the clouded sky” and “tattooed rock”

𝔠 nicknamed Te Maunga Tapu (“the sacred mountain”), the volcano lies within a caldera (collapse crater) area

𝔡 the actual numbers of Europeans who visited New Zealand’s version of the “8th Wonder of the World” was not as high as might be thought, owing to the terraces not being easily accessible – from the closest settlement Rotorua it was a trek over hills by horse or buggy followed by a canoe trip and the last section on foot [New Zealand’s Pink and White Terraces’, (Tourism NSW), www.media.newzealand.com]

𝔢 English novelist Anthony Trollope was one of the European ‘celebs’ who fronted up to bathe in the pools and sleep in a whare (Māori hut) next to the terraces (NZ Geo). Trollope found nothing like its waters in the world – you strike your chest against it, it is soft to the touch, you press yourself against it and it is smooth[Australia and New Zealand, (Vol.II, 1873]

 

Finland’s Magnetic Island: Jussarö, A Danger to Shipping

Coastal geology & environment, Regional History, Travel

Its been called a ghost town but the island’s massive concentration of iron ore under the sea⧆ exerts a powerful magnetic pull on passing ships and boats. The island of Jussarö is one of some 40,000 (and counting) islands off the coast that form Finland’s vast archipelago⌖.

(Image: julkaisut.metsa.fi)
(Source: Abandoned Spaces)

The “ghost town” tag comes from the closure of the island’s iron ore mining works in 1967☯ due to a decline in the world price for the mineral (‘Jussarö’, www.en.jussaro.net) …leaving the landscape scattered with the remnants of old industrial buildings abandoned to nature.

Hanneke Wrome (Image: alchetron.com)

Compass interference, a danger to shipping
The dense concentration of iron ore deposits within the island has been known to make the navigation equipment of passing vessels in the Gulf of Finland go haywire. The magnetic force emitted by the island tends to make ships malfunction and their compasses point in the wrong direction. Historically, a consequence of this has been a large incidence of marine accidents and shipwrecks in the vicinity. In 1468 the Hanseatic League cargo ship ‘Hanneke Wrome’ (or ‘Vrome’) was caught in a storm and wrecked near Jussarö island with the loss of over 200 lives and a vast quantity of expensive fabric, barrels of honey, gold coins and jewellery (‘Finland’s abandoned iron ore mine’, Abandoned Spaces, Bojan Ivanov, www.abandonedspaces.com). Perhaps the most famous shipwreck, known as “Jussarö I”, is a early 16th century ship belonging to the fleet of Swedish king, Gustav I Vasa (‘Jussarö Island’, www.visitraseborg.com). Given this hazard, Jussarö has been a haven for pilot stations and lighthouses (the island’s earliest pilot station dated from early 19th century).

Sundharu lighthouse

Raseborg’s teeth “ship trap”
Several smaller islands and islets south of Jussarö collectively known as Raseborgs gaddama (Raseborg”s Teeth”) are particularly prone to shipwrecks. This area is known to have caused disturbances in navigation as early as the 17th century. In 1751 Swedish naval cartographer “Jonas Hahn was able to explain the phenomenon by the high iron content in the underwater rock formation in the area”. The Sundharu lighthouse was stationed on one of the skerries here to try to counter the danger (‘Finnish cases: Four case study areas. Case 1 – Jussarö ship trap’, www submariner-net.eu).

When the mining activity ended, Jussarö was taken over by the Finnish Defence Forces and used for military training and urban war simulation. After the army left in 2005 the island came under the administration of Metsähallitus, a state-owned authority in charge of national parks, wildlife and forestry. The main activity today is tourism with day-trippers regularly commuting from the mainland.

Postscript: The island’s 13th century footnote in history
Jussarö first gets a mention in medieval Danish documents, appearing in King Valdemar II’s Survey (or “Court Rolls”), a document compared to William the Conqueror’s Doomsday Book record. The ‘Survey’ of Valdemar II of Denmark (reigned 1202–1241) was a land register of Danish settlements and their populations, c. 1231 (Nils Hybel, The Nature of Kingship c.800–c.1300: The Danish Incident , (2017)). Jussarö is included in the royal survey apparently because it was on the Danish route map (www.en.jussaro.net).

(Source: nationalparks.fi)

𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨𓆨
⧆ the largest deposits of iron ore in Finland
⌖ Jussarö itself lies within the Ekenäs Archipelago
☯ the second time iron ore mining operations had been abandoned on Jussarö, previous it was mined, sometimes using Russian prisoners, from the 1830s to 1861

A Shipwreck Graveyard at the Top of the Harbour

Coastal geology & environment, Local history, Military history, Natural Environment

Rusting and decaying dinosaurs of the sea moored permanently off Sydney Olympic Park

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Walkers and cyclists doing the path section of Sydney Olympic Park that stretches from Bennelong Speedway (oops! I mean Parkway) to the Badu Mangroves that guard the northern edge of Bicentennial Park would be familiar with the sight of half-a-dozen or so shipwrecks sitting calmly in the waters of Homebush Bay.

🔺 HMAS Karangi: once an important contributor in the defence of Darwin against the Japanese attack, now decomposing incrementally in the bay

🔺 the “interpretative and scenic lookout”

ჱჲს A metal plaque on the ground alongside the trail directs the curious passerby to an old wooden viewing platform where you can observe these maritime relics redolent of rotting timber and rusting metal. This spot contains the ship-breaking ramp (or what remains of it) that was used to dismember these ex-naval vessels. Missing is the wooden crane (presumably submerged) and the telescope.

🔺 The ship-breaking dock

ჱჲს The story of how these ships ended up here begins in 1966 when the Maritime Services Board approved the use of land here as a ship-breaking yard for the Port of Sydney. From 1970 till to the early Nineties private companies leased the yard to demolish hulks which had surpassed their use-by-date.

ჱჲს With the passage of time, left to nature and the elements, a number of these ex-ships have experienced an almost complete organic makeover. The dense mangroves of the bay have invaded the vessels, turning them into what one observer described as “a floating mangrove forest” (May Ly) and another, “a floating rusty relic forest” (Ruth Spitzer). The stricken and abandoned vessels are now a haven for local coastal birdlife (at dusk the hovering and nesting white gulls are easy to spot aboard the arboreal hulls).

ჱჲს The most striking example of this process of afforestation of wrecks is the SS Ayrfield. The UK-built steam collier, which ended up in Homebush Bay in 1972 after World War 2 service, is spectacularly overgrown with mangroves, a dense armada of trees literally bursting out of the ship’s disappearing hull and threatening to swallow it whole! High-rise residents in the Wentworth Point estate and people  strolling along the waterfront of the Point are afforded the best views of the organically-refashioned Ayrfield.

ჱჲს Also warranting special mention for a similar makeover courtesy of its biotic vibrancy–albeit much more obscurely located around the bend close to the Waterbird Sanctuary–is the 1924-built SS Heroic. The Heroic, a steam tug boat, saw service in both world wars before being consigned to the Homebush Bay cast-iron graveyard. Hidden behind a cloak of thick mangroves, you need to position yourself right on the muddy edge of the water and crane your neck to get a decent sighter of the nature-engulfed old tug boat. Its predicament, mirrors the Ayrfield’s but in a less advanced stage of arboreal encroachment.

ነሃጣፈነ A curious footnote to the 50 year-presence of the scuttled and abandoned ships in Homebush Bay is that the vessels, despite the egregiously bad state they are in, are ‘protected’ by legislation (under the Commonwealth Historic Shipwrecks Act 1976).

     

Materials referenced:

‘Shipwrecks of Homebush Bay’, (May Ly), 30-Jul-2013, www.weekendnotes.com

‘Graveyards of a different kind at Homebush Bay’, (Ruth Spitzer), 2015, www.ruthspitzer.com

Yucatán’s Not So Insular Peninsula, Mérida 3: A Subterranean Plunge in the Cénotes

Coastal geology & environment, Regional History, Travel
Tecoh cénote

Our last day at Mérida was more or less entirely given over to exploring a local geological feature in the region that Yucatán is world-famous for – the cénote✳ (Pron: say-NO-tay). Cénotes are natural pits, large sinkholes in the ground formed when limestone bedrock on the surface collapses exposing groundwater underneath. The ones we visited on that day were subterranean, deep down below ground level in cave formations in sites sheltered by overhanging cliff-faces. The cénotes in Southern Mexico are very popular with divers and snorkellers and the more accessible ones usually require the payment of an entry fee (from about 50 to 100 Pesos each). To get into the water at many cénotes you need to make a steep descent on rickety old ladders, although not all cenotes are sunk deep into the earth’s surface…some other cénotes like the one we saw in the Bay of Pigs in Cuba are located just below the ground and just look like natural pools surrounded by worryingly jagged rocky ledges.

Guía José conducts a cartography class in the field!

It was a decent old drive to reach our first Yucatán cénote, it was located in a place called Tecoh, quite remote, dry-parched and harsh land, real sagebrush territory! Our sociable guide for the day, José, laid down a map of the Peninsula on the ground and explained a bit of the cénote story. The ancient Maya people apparently used the cénotes for both practical and religious purposes. In a landscape (Yucatán) with hardly any rivers to speak of and quite few lakes, the cénotes provided a much-needed source of fresh water. The Maya also used them, it is believed, for sacrificial offerings sometimes. José’s finger traced a circuitous line around much of the map, pointing out the location of cénotes which seemed to be dotted all over the place. After we had swam in the first cénote I asked José who clearly relished the whole cénote experience if he had swam in every cenote in the state. José chuckled and indicated that there was over 2,000 cénotes all over the Peninsula, and he might need another 20-30 years to reach that target!

The roof of something deep, dark & delightful…

Cénote Dive-and-Snorkle
The ladder going down to the water-level was a concentric spiralling contraption of wooden steps which were in far from mint condition (words like flimsy and haphazard come to mind), necessitating that we made sure we trod fairly cautiously on each rung. At the bottom was a pretty primitively constructed wooden platform with only a small recess in the wall of the cave where we crammed our clothes and bags into every possible crevice.

Being a hesitant auto-immerser in any deposit of water greater in scope than a domestic bathtub, an aquatic prevaricator who can hold his own and delay with the best of them, I coaxed and eased myself with glacial speed into the seemingly bottomless, blue-turquoise chasm. The water was a little cool at first but I soon accustomed to it. The water quality looked pristine despite it being in constant by visitors, I was attracted by the appearance of a myriad of tiny colourful fish visibly close to the surface. The pool looked very deep…José speculated at least forty metres deep. Above us small birds flitted around the cave, dipping and diving in and out of several holes in the roof that have formed over the millenniums. The light emanating from the holes through tufts of vegetation provided a kind of natural spotlight projecting on to the water, giving the entire cavern a magical glow.

The beautiful azure water!

After a half-hour or so’s frolicking in the cénote Jose coaxed us out with the promise of a visit to an even more spectacular cénote that was only a short distance away at Carretera tecoh-telchaquillo. To get to the second cénote site we had to travel on more bumpy dirt roads, passing through several gates taking us onto different land-holdings. As we approached each closed gate, two small chicos (boys) that José had brought on the trip, would alight on a signal from the driver and scamper up and open the gate for the mini-bus◘.

Aquanauts of an ancient cénote!

An idyllic natural swimming hole full of picturesque delights
Cénote número dos managed to meet the high expectations of Jose’s extravagant rhetoric, and then some! It was a wider, deeper cave and the pool had a considerably more expansive mass of water. When we got to the cliff overlooking the cénote there was already a quartet of scuba-divers equipped with underwater cameras foraging around below the surface (“Japanese tourists”, they looked like to me). The drop from the top to the base platform was longer than the first cénote but glad to say the ladder was in better state with one long, straight descent to a three-quarter way platform and then a shorter ladder to a lower platform where you enter the water. José as usual wasted no time in shedding his T-shirt and thongs and diving into the sparkling abyss, following swiftly by the two boys. With everyone else quickly into the water, I paused briefly to take a few shots of the vast cavern and its water-treading occupants, before doing likewise. The pool was many metres deep (hence the presence of the scuba-divers), so once in I treaded water for a bit before swimming out to the middle of the water where someone had helpfully anchored a red buoy to the bedrock floor.

With one arm securely clasping the floatation device I took a breather, and while I was there I was able to have a good look around the cavern roof above. Bright beams of light from the limestone roof illuminated the water surface like a spotlight and made it possible to make out the presence of a few hibernating Mexican bats suspended from various nooks and niches of the craggy rock. Our guide pointed out that the walls of the cave accommodated a host of other small creatures like iguanas and spiders. I liked how there were lots of long, long vines growing over the edge of the cliff and cascading down almost to the water✥…the vines looked sturdy but I wondered if they were strong enough for any daredevil adventurer brave (or stupid) enough to swing off them from the roof into the water?

A gate-opening chico & the word of Señor Jesuchristo

Community lunch with the family
The fee for the cénotes excursion included lunch in the casa of a local family that José took us to in nearby Pixyá. When we got there the niños were still hanging round so I wondered if this was José’s lugar. A number of the humble dwellings on that street had the identical message in Spanish painted on the front walls – a quote from Señor Jesuchristo (Ro. 6:23), something about paying fish when you die in order to ensure eternal life (my idiomatic interpretation anyway!).

A typical Yucatán Sunday spread!

As small livestock wandered around the yard inquisitively, we were guided to our seats at a long, outdoor table under a covered awning. José and the dama of the house brought out the food, in no time we were tucking into a delicious meal of meats (mainly pollo) and a smorgasbord of vegetable dishes. José produced jugs of a home-made lemon or limonáda drink to compliment the midday meal. The authentic, community “Sunday lunch” with the family capped off the day of subterranean cénote adventures to a tee!

Setting out again from Pixyá in José’s mini-bus, we bounced along the dusty dirt road towards Mérida, the further we went the better, and therefore the smoother, the road surface got. Back in town, having developed a craving for hot choc drinks after some early disappointing coffee experiences on the tour, I sought out a late afternoon caliente chocolate at the Italian Coffee Company (this seems to be a sizeable franchise business chain in different parts of Mexico, noticed they had several shops around where we stayed in Puebla).

Being our last night in Mérida, Hector took us to one of the liveliest and most crowded nightspots he knew in Mérida City Centre, Le Negrita Cantina (corner of Calles 49 and 62). We got a sensory dose of typically pulsating Mérida night-life here…wall-to-wall people seated cramped close together munching burritos (my non-appearing cerveza seemed to have been redirected back to the brewery – in a nearby town!) in an enclosed firetrap, wait-staff constantly circling round the tables with trays of margaritas, sangritas and micheladas looking for homes. Couldn’t really hear ourselves speak with the din going on, but the exciting buzz of the non-stop musical band and the dancing was great to experience!

≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡—≡-≡—≡—≡—≡
✳ the word derives from ts’onot, used by the low-land Yucatec Maya to refer to any location with accessible groundwater
possibly José was being conservative with even that formidable number – other estimates (eg, www.aquaworld.com.mx) place the number of cénotes in the Yucatán Pen at in excess of 5,000
◘ the two small children doing the leg-work, I presumed, were José’s own niños
✥ some of the hanging vines in cénotes resemble the icicle-like stalactites often seen in caves