Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Ancient Forest Emerges From Beneath Takapuna Beach


Ancient Forest Emerges From Beneath Takapuna Beach

In recent days the sand near low water in the middle of Takapuna Beach, Auckland, has shifted and exposed the long buried remains of an ancient forest.

Many long-time locals say they have never seen it before, although some of the soft sticky mud that it is buried in has been uncovered in other parts of the beach on odd occasions in the past.


Auckland geologist Bruce Hayward visited the newly exposed fossil forest this week. “This is an exciting new discovery and is quite different and much older than Takapuna Reef’s famous fossil forest preserved in the lava flows from Pupuke Volcano”, he says.


“This new fossil forest consists of many small tree stumps in growth position in an ancient soil. It is clear that the trees became established on the surface of a thick white rhyolitic ash deposit, and in turn they have been buried and preserved by another thick creamy-white volcanic ash bed”. Similar thick rhyolitic ash and ignimbrite deposits occur in a number of low-lying parts of Auckland. Elsewhere they have been dated at close to 1 million years old and were erupted by gigantic explosive blasts from a volcano in the vicinity of Mangakino, near Taupo.

A similar sequence of white volcanic ash and peat occurs in Shoal Bay and was exposed a few years ago by earthworks when the Esmonde Rd interchange for the northern motorway was being enlarged. Similar aged fossil forests are permanently visible in eastern and southern Auckland in low sea cliffs at Pakuranga, Takanini and Waiuku.

“The fossil tree stumps and fallen branches and twigs are black, but they have not been burnt” says Dr Hayward, “instead they have been carbonised during their preservation and fossilisation. A specialist could study their cell structure and identify the kinds of trees present. Most of the trees are small and less than 15 cm diameter, but larger trees were in the neighbourhood as I found a large lump of kauri gum in the ancient soil.”

In places the volcanic ash has weathered to clays and is soft and sticky but in some places it has been hardened by remineralisation and some of these rocks stick up 30 cm above the present beach level.

History tells us that it will not be too long before the sands shift back and once again bury Takapuna Beach’s hidden secret – the oldest fossil forest on the North Shore.

Ends


ends

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Trade Plans: Prime Minister's Speech To International Business Forum

"The work to improve public services, build infrastructure, and solve social problems is possible only because we have enjoyed sustained, solid economic growth. A big reason for that is the Government’s consistent agenda of economic reform, and our determination to open up more opportunities for trade with the world." More>>

ALSO:

Media: TVNZ Flags Job Cuts To Arrest Profit Decline

Chief executive Kevin Kenrick said the changes were aimed at creating "a sustainable future video content business for TVNZ in an ever-changing media market." More>>

ALSO:

Reserve Bank: Wheeler Keeps OCR At 1.75%

Reserve Bank governor Graeme Wheeler kept the official cash rate unchanged at 1.75 percent, as expected, and reiterated his view that the benchmark rate doesn't need shifting for the foreseeable future. More>>

ALSO:

Retail: Pumpkin Patch Brand, IP Sold To Catch Group

The receivers of failed children's clothing retailer Pumpkin Patch have confirmed that the company's brand and intellectual property have been sold to Australian online retailer Catch Group. More>>

ALSO:

Oil: 2017 Block Offer Petroleum Tender Launched

New Zealand is well-placed to take advantage of the economic benefits of oil and gas exploration, Energy and Resources Minister Judith Collins announced today at the launch of the 2017 Block Offer petroleum tender. More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news