Lost continent of Zealandia that sank into the sea 23 million years ago is revealed in unprecedented detail in new maps of the ocean floor
- Geologists from New Zealand created the new tectonic and bathymetric maps
- They are available both in print and in interactive from on a new web portal
- Covering some 1,930,511 square miles, Zealandia is a largely sunken crustal mass
- It is believed to have broken off of a supercontinent over 79 million years ago
- Zealandia was confirmed as meeting the criteria for being a continent in 2017
The lost continent of Zealandia that sank into the sea 23 million years ago has been revealed in unprecedented detail in new maps of the ocean floor.
Geologists from New Zealand drew up the tectonic and bathymetric maps of the Earth’s eighth continent — which spans some 1,930,511 square miles.
The maps — along with graphics and other geoscience data — can be accessed through the new ‘E Tūhura – Explore Zealandia’, or ‘TEZ’, website.
Zealandia — confirmed as meeting the criteria for a continent in 2017 — submerged after breaking off of the Gondwanaland supercontinent over 79 million years ago.
The lost continent of Zealandia that sank into the sea 23 million years ago has been revealed in unprecedented detail in new maps of the ocean floor. Pictured, a tectonic map of the 1,930,511 square mile continent of Zealandia, only a small part of which outcrops on land. In the map, continental crust is shown in red, orange, yellow and brown hues, while oceanic crust is shaded blue. Volcanic island arc crust is pink, while large igneous provinces are green
‘These maps are a scientific benchmark, but they’re also more than that — they’re a way of communicating our work to our colleagues, stakeholders, educators and the public,’ said map author and geologist Nick Mortimer of GNS Science.
‘We’ve made these maps to provide an accurate, complete and up-to-date picture of the geology of the New Zealand and southwest Pacific area — better than we have had before.’
‘Their value is that they provide a fresh context in which to explain and understand the setting of New Zealand’s volcanoes, plate boundary and sedimentary basins.’
The TEZ web portal will allow geologists and interested members of the general public to explore the geology of Zealandia from the comfort of their homes and offices, said project head and geophysicist Vaughan Stagpoole.
‘Users can zoom and pan around different thematic geoscience webmaps of the region. They can readily view and interrogate the maps and turn layers on or off,’ Dr Stagpoole added.
‘They can also query features in the layers and generate custom maps of their own.’
More information will be added to the interactive site as new research findings are collected, the team said.
Geologists from New Zealand drew up the tectonic and bathymetric maps of the Earth’s eighth continent — which spans some 1,930,511 square miles. Pictured, the bathymetric map of Zealandia, which has been composed using data from the Seabed2030 project, which is a global initiate to map the entire planet’s ocean floor by the end of this decade
Three interactive, multi-layered maps are available through the TEZ platform.
The first — the tectonic map — displays geological interpretations of the types and ages of the crust of Zealandia, along with the boundaries and motion vectors of geological plates, the depth of subducting slabs and the locations of volcanoes.
The bathymetric web map shows the shape of the solid land and seabed of Zealandia and also depicts coastlines, territorial limits and the names of major undersea features.
Finally, the ‘Geoscience data’ map brings together data from various sources — including GNS Science’s 1:250,000 scale geological map of NZ and records of samples from the national rock, mineral and geoanalytical database, ‘Petlab’.
ZEALANDIA: EARTH’S ‘LOST’ EIGHTH CONTINENT
Pictured, the continent of Zealandia
‘Zealandia’ — also known as ‘Te Riu-a-Māui’ in te reo Māori — is a largely submerged mass of continental crust.
Zealandia sank when it broke off from the supercontinent of Gondwanaland some 83–79 million years ago.
The concept of Zealandia was first proposed in 1995, but only recognised as a continent in its own right in 2017.
It is twice the size of the largest micro-continent and also meets the continental criteria in crustal thickness and density.