INTRODUCING THE

FROGNET RIGID PLATE

RECONSTRUCTION MODEL

A BASEMENT TERRANE MODEL

PaleoGIS and PaleoClimate

Users Conference

5 November 2014

Marie-Aude Bonnardot

Lynn Pryer

Jane Blevin

• FROGTECH are global experts in processing geophysical datasets,

structural and tectonic interpretations, basin analysis and resource

assessment.

• FROGTECH’s basement and geodynamic specialists have global expertise

in mapping basement terranes and tectonostratigraphic provinces.

• SEEBASE™ is a depth-to-basement model and FROGTECH’s signatureproduct. It stands for Structurally Enhanced view of EconomicBASEment.

FROGTECHWHO WE ARE AND WHAT WE DO

Australia-based

Geological consultancy

OZ Proterozoic SEEBASE™Structural Enhanced View of Economic BASEment

Geological calibration

Integration

Interpretation of non-seismic and seismic data

SEEBASE™ Structurally Enhanced view of Economic Basement

Bottom-UpApproach

FROGTECH’SBASEMENT APPROACH

TECTONIC HISTORY

Precambrian and Phanerozoic

Basement Evolution and Assembly

Plate Reconstructions

Tectonic Events and Response

BASIN PHASES

Petroleum Systems and Play Evaluation

Sediment Provenance and Supply

Palaeogeography

Stratal Geometry

Accommodation history

BASEMENT GEOLOGY

Terranes Type and Age

Composition

Structure

Crustal Architecture

Heat Flow

BASIN ARCHITECTURE

SEEBASE™ depth-to-basement

Structural Analysis

Bottom-UpApproach

FROGTECH’SBASEMENT APPROACH

What is a “Basement Terrane” ?

“……. a discrete, mappable, structurally bounded block of crust of regional extent with a tectonostratigraphic history different to that of neighbouring terranes.” (e.g. Jones et al., 1977; Howell, 1995).

FROGTECH has also subdivided

terranes based on rheological

differences within a terrane.

Why focus on “Basement” ?

Foundation onto which sediments are deposited.

Basement terranes provide essential informationto understand basin evolution and petroleumsystems elements, including basin geometry, rateof subsidence, heat flow distribution, maturationhistory, migration pathways and distribution ofreservoir and source rocks.

GLOBAL TERRANES TERRANES INTERPRETATION

How to interpret “Basement Terranes” ?

Outcropping or deeply buried basement, onshore or offshore basement

Cross-section and DEM

Lithology Maximun Stratigraphic Age

Surface Geology

Compilation and georeferencing of published data, i.ecross-sections, structural maps, surface geology….

• Data Compilation, Data Processing and Grid Stitching• Spectral Analysis and Grid Enhancement• Standard and Proprietary Filters• Gravity and Magnetic Modelling

GLOBAL TERRANES TERRANES INTERPRETATION

Potential field data to assess geometry and physical properties

GLOBAL TERRANES TERRANES INTERPRETATION

• Tectonic event information over wide areas canhelp to identify terranes that are equivalent inage and composition, i.e. analogous parts ofconjugate margins

Correlation of Terranes

Africa

S America

Type

Accreted Arc

Accretion Complex

Craton

Highly Attenuated

Undifferentiated Continental

Restoration of South America against Africa

(Africa fixed).

South America is colored by terranes type.

High-Pass 300km of the Bouguer gravity is

shown in Africa with terranes outlines.

DEM: SW Pacific, South and Indian oceans

GLOBAL TERRANES TERRANES INTERPRETATION

Example

Global Free Air Gravity

GLOBAL TERRANES TERRANES INTERPRETATION

Example

Terrane analysis

GLOBAL TERRANES TERRANES INTERPRETATION

Example

Proterozoic OZ SEEBASE™ and

New Zealand ECS SEEBASE™

GLOBAL TERRANES TERRANES INTERPRETATION

Example

FROGNETRIGID PLATERECONSTRUCTION MODEL

R & D

PLATE POLYGONS

ROTATIONS

• 1996 - present

Global interpretation of basement terranes, plate reconstructions and

development of tectonic events database including basin response.

• 2006 - 2012

In-house development of the FROGTECH Global Terranes Database including

an events database. In-house plate reconstructions and joint development of

PaleoArc with Cambridge Paleomap Services Ltd.

• 2013-14: Product Release

2013: Release of the FROGTECH Global Terranes Database and GIS

2014: Import of FROGNet Plate Model into PaleoGIS

2015: Release of FROGNet Plate Model for multi-client subscription

RESEARCH AND DEVELOPMENT

FROGNetPlate Model

FROG NET RIGID PLATE MODEL

Terrane Type

Accreted Arc

Accretion Complex

Accretionary Wedge

Continental Arc

Craton

Cratonised Arc

Forearc-Accretionary Wedge

Highly Attenuated

Island Arc

Oceanic Crust

Oceanic Plateau

Ophiolite

Transitional

Transitional magmatic

Transitional non-magmatic

Undifferentiated Continental

Undifferentiated Orogenic Belt

FROGNet plate polygons are subdivisions of basement terranes

Approx. 1500 continental fragments

Approx. 1250 oceanic fragments

Plate Polygons Symbology

Craton

Continental - Undifferentiated

Extended Crust

Oceanic Plateau

Ophiolite

Oceanic Crust

FROGNET PLATE POLYGONS ANDGLOBAL TERRANES DATABASE

Global Terranes

Database

FROGNet Plate

Polygons

Approx. 1300 continental fragments

Approx. 160 oceanic fragments

FROGNET ROTATIONS

Re-adjustment of published rotations

based on FROGTECH knowledge of

tectonostratigraphic provinces

+

Global Terranes Database, including revised LOC

+

=

FROGNet Rigid Plate Model

Rotation Chains

Published paleomagnetic data and relative motion

Oceanic Magnetic Anomalies

Workflow

TECTONIC HISTORY

Precambrian and Phanerozoic

Basement Evolution and Assembly

Plate Reconstructions

Tectonic Events and Response

BASEMENT GEOLOGY

Terranes Type and Age

Composition

Structure

Crustal Architecture

Heat Flow

Obtain the most accurate position of plates through time

FROGNET ROTATIONS

Relative and

Absolute

Paleopositions,

Paleolatitudes

-

Intraplate

Deformation

AF

MAD

AUS

ANT

NZ ?

What is the main challenge in plate reconstruction?

BENEFITS OF THE FROGNETRIGID PLATERECONSTRUCTION MODEL

PALEOGEOGRAPHY

INTRAPLATE

DEFORMATION

TERRANE ANALYSIS

A high resolution terrane map

to refine paleopositions

• Complete geological description of plates provides more constraints to improve relative paleopositions.

• Mimic deformation processes:

Change of plate geometry at megaterrane scale based on basement terrane information, i.e. terrane maximum age

Example-1PALEOGEOGRAPHY

A high resolution terrane map to refine paleopositions

• Mimic deformation processes:

Distribute intraplate deformation across several terranes and better control gaps and overlaps inherent to rigid plate models – provide higher resolution to understand basin phases

Example-2INTRAPLATE DEFORMATION

Dolomitised CarbonatePlatform Margin

Carbonate Platform

r

r

r

r

r

r

r

r

IRANIRAQ

THEGULF

KUWAIT

Restricted basinfilled with

source rocksand evaporites

TURKEY

Late Permian-Early TriassicOceanic Crust

(Neotethys)

Radiolarites

0 200

km

S

Dolomitisedcarbonate platform

Restricted basin withbituminous carbonates

and evaporites

Outercarbonateplatform

Rift basin

Radiolarites+

carbonateturbidites

Stretchedcontinental

crust

Oceaniccrust

Arabian Plate

Mid-Late Jurassic paleogeographic

reconstruction for NE Arabian Plate

from Goff (2006) showing

deposition within a restricted,

evaporitic basin with source rocks

overlain by evaporites.

Terrane analysis

• Can be used to predict variations in basement rheology during identifiedtectonic events. For example, mobile belts tend to strain-soften whilecratonic blocks tend to strain-harden. This leads to strain partitioning andstrain localisation into mobile belt terranes.

TERRANE ANALYSIS

Hercynian reactivated faults

N

Hercynian Event

Hercynian subcrop map of North

Africa from Boote et al (1998)

showing the regional pattern of

Hercynian “arches” (in pink) and

reactivated basement structures

Example-3

Terrane analysis

• Provides a complete revision of the Limit of Oceanic Crust (LOC), withtransitional margins wider than previously interpreted.

• Combined with additional methodologies, such as seismic interpretationand gravity modelling, the terrane analysis provides new insights on keymechanisms that control margin development, i.e. distribution of hyper-extended margin

TERRANE ANALYSIS

Plate Tectonic

Events, Kinematics

Basin Architecture &

Evolution

Paleogeography

Terrane

Boundaries

Composition

Fabric

TE

RR

AN

ES

Total Sediment

Thickness

Migration Pathways

& Fluid Focusing

Reservoir & Seal

Quality

Trap Timing, Size & Distribution

Maturity + Hydrocarbon

Generation

PETROLEUM PLAY ELEMENTS

FROGNET IN PALEOGIS

DATA

TERRANES

ATTRIBUTES

TIME SLICES

Standard PaleoGIS fields

• Plate Code

• Appearance / Disappearance Age

• Plate Name

• Basic Symbology

FROGNET MODELDATA

Default Layers

• Countries

• Coastlines

• Coordinates grid

Basement Terranes fields

• Terrane Type

• Stratigraphic Minimum Age

• Minimum Age (Ma)

• Stratigraphic Maximum Age

• Maximum Age (Ma)

• Basement Age (Ma)

• Interpretation Information

(dataset used)

• Abstract

• References

• Megaterrane

*Provided as Layer files with pre-defined symbology

FROGNET MODELTERRANE ATTRIBUTES

• Terrane Type*

• Stratigraphic Minimum Age*

• Minimum Age (Ma)*

• Stratigraphic Maximum Age*

• Maximum Age (Ma)*

• Basement Age (Ma)*

• Interpretation Information

(dataset used)

• Abstract

• References

• Megaterrane*

Bowers

The Bowers Terrane comprises the

Cambrian Glasgow Group of primitive

volcanic arc affinity (>2km of mafic-

intermediate volcanics and gabbros)

grading up into a thinner (~200m)

regressive marine sequences of the Molar

and Mariner Groups (from limestones to

sandstones) spanning the Middle – Upper

Cambrian (Ferracioli et al., 2002). The top

of the sequence is formed by the Late

Cambrian Leap Year Group, comprising

<4km of continent-derived sandstones and

conglomerates (Tessensohn & Henjes-

Kunst, 2005). The terrane is separated from

the Wilson terrane by the Lanterman Fault

suture (Ultra-mafic rocks, HP-UHP

metamorphic rock) and from the Robertson

Bay terrane by the Leap Year fault marked

by the Millen Schist Belt. Accretion and

suturing at the East Antarctica Craton

margin is usually related to subduction

during the Early Paleozoic Ross Orogen.

The Bowers terrane has been intruded by

the Devonian – Early Carboniferous

Admiralty Suite of calc-alkaline I-type

intrusives (Ferracioli et al., 2002).

Abstract

FROGNET MODELTERRANE ATTRIBUTES

Type

Accreted Arc

Accretion Complex

Continental Arc

Craton

Cratonised Arc

Forearc-Accretionary Wedge

Highly Attenuated

Island Arc

Oceanic Crust

Oceanic Plateau

Transitional magmatic

Transitional non-magmatic

Undifferentiated Orogenic Belt

Minimum Stratigraphic Age

Basement Stratigraphic Age

Maximum Stratigraphic Age

Megaterranes

Basement Terranes Fields

• The FROGNet Rigid Plate Model includes 25 Time slices that describe the

geodynamic setting in a reconstructed space.

• In the 2015 release, the time slices include:

• Tectonic Events Database: tectonic events are shown on the relevant

time slices. Each tectonic event is fully documented with a unique name,

maximum/minimum age, event age, category, technical abstract and

references.

• Tectonic Boundaries: interpreted for each time slice and derived from the

basement terranes and tectonic events databases.

• The 2016 release will also include:

• Paleostresses at terrane scale

• Terrane type through time.

FROGNET MODELTIME SLICES

CONCLUSIONS

• Geology-driven plate model

• Detailed integration and interpretation of georeferenced

scientific datasets (geological maps, potential field

datasets, wells, seismic data)

• Quick access to global summary of key characteristics of

basement terranes/plate polygons (type, age, major

composition, tectonostratigraphic history)

Enhances understanding of the relationship between

basement terranes, the overlying sedimentary basins and

their mineral and petroleum resources

CONCLUSIONS

FROGNet Rigid Plate Model

• Terranes add a rheological component to the plate model and provides a first pass assessment of stress partitioning and strain localisation.

CONCLUSIONS

Terrane Type

• Rotations in the models cover the Phanerozoic (0 to 540Ma)

• Terranes are interpreted and described up to the Precambrian, i.e. useful for Precambrian mineral systems and rising interest for unconventionals.

FROGNET RELEASE

FROGTECH Pty Ltd

Suite 17F, Level 1

2 King Street

Deakin West ACT 2600

T +61 (0)2 6283 4800

F +61 (0)2 6283 4801

E info@frogtech.com.au

W frogtech.com.au

Contacts:

Marie-Aude Bonnardot, PhD

Senior Geoscientist

Jane Blevin, PhD

CEO and Business Development

Lynn Pryer, PhD

Principal Geoscientist