The Lachlan Orogen of Eastern Australia: Revolutionizing the resource prospectivity game in Australian and globally - Ross Cayley - CET Seminar - 21st May 2015

1. The Centre for Exploration Targeting (CET) is pleased to invite you to a
Guest Lecture in the CET Seminar Series given by
Dr Ross Cayley
“The Lachlan Orocline of Eastern Australia. Revolutionizing the resource prospectivity
game in Australia and globally”
ABSTRACT
Since the first applications of modern plate tectonic theory to Eastern Australia, the Lachlan Fold
Belt (LFB) has been repeatedly interpreted as an unusually wide and squat, composite orogen,
an amalgamation of multiple linear, orogen-parallel Early Paleozoic accretion or rifting events and
multiple arc complexes, some developed independently, some simultaneously. However, modern
structural and stratigraphic mapping, and aeromagnetic, gravity and deep seismic reflection data
now constrains a new geodynamic model: a simple unifying solution for the whole LFB from far
north Queensland to Tasmania. This model develops the idea that only one, continent-dipping,
subduction zone was active in eastern Australia in the Ordovician-Early Devonian. Its formation
involved continent-scale reorientations of the geology. The model effectively doubles the apparent
LFB width, disrupting and redistributing any- and all- mineral systems formed within the orogen prior
to 400Ma in the process. It is a brand new conceptual template for predicting the location of buried
mineral systems in all of Australia’s eastern States – the global type-locality for a new geodynamic
model that rethinks the lower mantle processes that drive continental collisions.
BIOGRAPHY
Ross Cayley is a structural and field geologist at the Geological Survey of Victoria (GSV). He is developing
a radical new geodynamic model for the Australian continent for the Cambrian – Devonian. An overview
of this work was incorporated as the global type-locality for a new geodynamic model for continent collision
developed with Monash University research collaborators. Published recently in NATURE, this work has
fundamental implications for terrane prospectivity analysis across Australia, and globally.
VENUE Woolnough Lecture Theatre (1.07), Geography and Geology Building
University of Western Australia, 35 Stirling Hwy, Crawley 6009
Pay parking is available along Fairway (approx. $1.50 per hour)
TIME 4:00 - 4:45pm Thursday 21st May 2015
You are invited to join us afterwards for refreshments provided by our local
SEG Student Charter in the Resource Room, Robert Street Building.
4:00 - 4:45pm
Thursday 21st May 2015
Woolnough Lecture Theatre
Dr Ross Cayley
The Lachlan Orocline of Eastern Australia. Revolutionizing
the resource prospectivity game in Australia and globally