President's Lecture 2008

The GSNZ President, Dr Nick Mortimer (GNS Science, Dunedin), will touring the country from March through to June, 2008.

An itinerary is given below.

Nick Mortimer

A BLUFFER'S GUIDE TO CENOZOIC VOLCANIC ARCS

AND BASINS OF THE SW PACIFIC

Abstract

The northern half of the continent of Zealandia is bordered by an array of volcanic arcs and deep basins that have formed over the last 85 million years. The best studied of these are the modern Taupo-Kermadec-Tonga volcanic arc and the associated active backarc Havre Trough and Lau Basin. This talk will summarise the present state of knowledge of the lesser-known ridges and basins to the west, especially the Norfolk and South Fiji Basins, the Three Kings and Colville Ridges and the Northland Plateau.

In the last 10 years, data from two ONSIDE (Offshore Northland SeismIc and Dredging Expedition) cruises has led to considerable progress in our understanding of the geology of these major bathymetric features. The interval 17-25 million years ago appears to have been a time of considerable tectonic change north of New Zealand. There is reasonable consensus on the tectonic development of the region north of New Zealand after 17 Ma and major (but ultimately very testable) differences on 85-25 Ma tectonic models.

A knowledge of the evolution of the whole Cretaceous-Recent SW Pacific arc-backarc system can help us understand the geotectonic processes that control the longevity of arcs and formation of backarc basins around the world.

At the beginning of the talk, Nick will talk a bit about his background, and say a few words about the Geological Society.

Itinerary

BRANCH

DATE

CONTACT

Auckland

Tue 18 Mar

Jan Lindsay (l.lindsay_at_auckland.ac.nz)

Hamilton

Wed 19 Mar

Rochelle Hansen (rjhansen_at_waikato.ac.nz)

Dunedin

Wed 26 Mar

Andrew Gorman (andrew.gorman_at_otago.ac.nz)

Taranaki

Mon 31 Mar

Susan Burgess (susan_at_netmail.co.nz)

Taupo

Tue 1 Apr

Paul White (p.white_at_gns.cri.nz)

Palmerston North

Wed 2 Apr

Julie Palmer (J.A.Palmer_at_massey.ac.nz)

Wellington

Thu 3 Apr

Alan Orpin (a.orpin_at_niwa.co.nz)

Masterton

Thu 12 Jun

Val Lear (blueiris_at_slingshot.co.nz)

Christchurch

Tue 17 Jun

Phil Tonkin (horowai_at_paradise.net.nz)

Nelson

Wed 18 Jun

Peter Ballance (ballance_at_clear.net.nz)