The Geoscience Society of New Zealand calls on the Government and Dunedin City Council to stop the proposal to mine away
New Zealand’s most important terrestrial fossil site at Foulden Hills, near Middlemarch, Otago.
“New Zealand’s national identity is strongly bound to its unique plants and animals. We cannot stand by and see this
fountain of paleontological knowledge about where we have come from destroyed; particularly not for so little transient
local and national gain”, said Geoscience Society of New Zealand President Dr Jennifer Eccles.
The diatomite sediment that infilled this crater lake, 23 million years ago, contains the most extraordinary array of
exquisitely preserved plant, fish, spider and insect fossils in New Zealand. These fossils are unique and record the
previously unknown history and origins of a large portion of New Zealand’s present-day biota. They are all extinct
species. Many are the ancestors of NZ’s current biota but others record groups of plants and animals that are no longer
living here. To date, over 100 different species of plant fossils have been identified (mostly leaves, but also fruits,
seeds and wood). The plants include extremely rare fossil orchids, mistletoes, fuchsias and a host of other taxa that
link NZ’s biota to Australia, New Caledonia and South America. Forty fossil flowers have been found, many still
containing pollen, representing 15 plant families. Fossil flowers with associated pollen are extraordinarily rare
globally.
Amazingly preserved freshwater fish fossils include the oldest freshwater eel fossil in the Southern Hemisphere and the
oldest galaxiid whitebait in the world. Insects are NZ’s largest group of terrestrial animals. More than 50% of NZ’s
discovered fossil insects have been found in this one deposit and include over 200 different kinds from 21 families.
Four fossil spiders have also been found. All these fossils come from just a small area near the top of the deposit.
This unique site will hold hundreds more different kinds of fossils that will help paleontologists in future decades and
centuries document and decipher the rich history of NZ’s biota. The rich fossil collections already found could form the
basis of an important museum and information centre in Middlemarch.
“The diatomite at Foulden is an irreplaceable treasure box from which only a small proportion of its jewels have been
found so far”, said Geoscience Society Geoheritage Convenor Dr Bruce Hayward.
“Foulden crater lake fossils are as important to our understanding of the origins of New Zealand's biota as the UNESCO
Messel World Heritage Site in Germany is to understanding the history of Europe's biota”, said paleontologist Prof
Daphne Lee. Government-funded scientific drilling has revealed the full 120 m thickness of the diatomite sediment fill
of the crater. It is composed of thousands of 1 mm-thick layers, each deposited by annual algal (diatom) blooms. This
core provides a unique and truly world-class record of annual climatic fluctuations spanning a 120,000-year period
around 23 million years ago. Detailed international studies now and in the future will provide unprecedented detail of
annual climatic factors such as rainfall and greenhouse gas variability that will lead to better understanding of the
ancient El Niño-Southern Oscillation (ENSO) and other climate cycles. To do this requires preservation of a complete
sequence through the deposit in perpetuity so that future generations of scientists can use the inevitable new
technologies to interrogate the sequence and obtain increasingly more detailed information about the fossils and the
history of climate at that time. A deposit with this level of annual resolution is unknown in the Southern Hemisphere.
Recently released company documents say that the whole deposit will need to be mined to be economic and afterwards the
hole will fill with water and prevent access to any scraps that may have been left behind . Dr Eccles says “we recognise
that mining of this deposit would clearly provide access to much deeper levels and undoubtedly uncover many more fossil
treasures, but it would be unconscionable for us to support the proposed quarrying away of virtually the entire deposit.
This site is of international importance and it is beholden on us to protect it for future generations of scientists and
the public.”
ends