Fernando de Noronha Umberto G. Cordani - Acquacon · F.F.M. de Almeida ( 1955) - Geologia e...

A história geológica de FERNANDO DE NORONHA

Umberto G. Cordani

Instituto de Geociências - USP

1960’s - CONTINENTAL DRIFT and

PLATE TECTONICS

1960 - Cox & Doell – Earth’s magnetic reversals

1961 - Hess – History of ocean basins

1963 - Vine & Matthews – Magnetic anomalies

1968 - Isacks et al. – Seismology and global tectonics

1965 - Wilson – Young age of oceanic lithosphere

1967 - Hurley et al. – Brazil-Africa connection

1968 - Le Pichon – Sea floor spreading and

continental drift

South Atlantic fracture zone locations (names in black) and

Fernando de Noronha Ridge (black square) (modified from

Antobreh et al., 2009).

Bathymetry around the Fernando de Noronha

Archipelago

N

32º40´ 32º30´ 32º20´W

3º45´S

3º55´S

3000

2000

1000

500

500

100

50

100

50 Alto Fundo Drina

ARQUIPÉLAGOFERNANDO DE NORONHA

Vertical profile of the volcanic edifice

500

1000

2000

3000

4000

0 10 20 30 40 50 60 70 (km)

M. Francês

Pedras SecasPico

Alto Fundo Drina

W E

23 km

(m)

MAPA GEOLÓGICO de FERNANDO DE NORONHA

1955 - F.F.M. de Almeida

1970 - CORDANI, U.G. – Idade do vulcanismo no Oceano Atlântico Sul - Bol. IGA USP,

#1: 9-75.

1972 - CORDANI, U. G. - Potassium-argon ages of rocks from the Brazilian South

Atlantic Ocean. In: Proceedings of the Symposium on Continental Drift. 1967,

Montevideo, Uruguay. - Transaction American Geophysical Union, Washington, DC,

USA, v.53. p.168 .

1977 – BERNAT, M. et al. – Datation par la méthode Ar-Ar de roches volcaniques des iles

brésiliennes de Fernando de Noronha et Trindade. – ORSTOM Ser. Geol. IX: 45-48.

2003 - CORDANI, U.G et al. - Cenozoic alkaline volcanism of Fernando de Noronha

Island. Field Trip T1. In: SOUTH AMERICAN SYMPOSIUM ON ISOTOPIC

GEOLOGY, Salvador: CBPM, 24p.

2004 - TEIXEIRA, W. et al. - “O paraíso do vulcão” – Ed. Terra Virgem, 168 p.

2004 - CORDANI, U.G. et al. – Novas determinações de idade pelos métodos K-Ar e Ar-

Ar para o Arquipélago de Fernando de Noronha – Revista da Fac. Ciencias, Universidade

Eduardo Mondlane, vol.1: 167 – 177. - Maputo, Moçambique,

2013 - PERLINGEIRO et al. - 40Ar/39Ar geochronology of the Fernando de Noronha

Archipelago and implications for the origin of alkaline volcanism in the NE BraziL – Jr

Volcanology and Geothermal Research, vol. 249: 140-154.

Personal involvment

Fernando de Noronha Arquipelago

Samples with radiometric ages TOTAL : 47

COLLECTORS

07 samples - J.C. Branner (?)

03 samples - F.F.M. Almeida – 1950 (?)

13 samples - U.G. Cordani – 1965

06 samples - M.C. Ulbrich – 1989-1999

12 samples - U.G. Cordani – 2003

06 samples - L. Kogarko – 2007

MAPA GEOLÓGICO de FERNANDO DE NORONHA

1955 - F.F.M. de Almeida

Stratigraphic column of the volcanic units

Quixaba Formation - basic to ultrabasic lava flows

(melanephelinites with OL, PY, MEL, intercalated with pyroclastic

levels and basanites).

AGE: 6.2 to 1.3 Ma (duration of volcanism = 5 Ma)

São José Formation – basanite and alkali basalt flows carrying

abundant mantle xenoliths (dunite, lherzolites, harzburgites) from

the source area of the parental magma.

AGE: 9.0 – 9.5 Ma, coeval to the Remedios volcanism

Remedios Formation – Pyroclastic deposits (agglomeraetes,

breccias, tuffs) intruded by a series of subvolcanic domes, plugs and

dikes (phonolites, essexites, trachytes, alkali basalts).


Fernando de Noronha - radiometric ages of

shallow intrusives - Remedios Formation

K-Ar Ar-ArSão Paulo laboratory

Fernando de Noronha – Remedios Formation

São Paulo laboratory - K-Ar ages of phonolitic domes

Melanefelinito da Formação Quixaba - Ilha Rata, derrame basal

UC-FN-37 / Whole Rock

0

50

100 % R a d

40Ar/39Ar Step-Heating Spectra for Runs 1417-01, and 1417-02 1417-03

0

1

2

3

C a / K

0 10 20 30 40 50 60 70 80 90 100

Cumulative %39Ar Released

0

2

4

6

8

10

A p p a r e n t A g e M a

A

B

C

D

E F

G

H

I

2.8 0.3 Ma*

Integrated Age = 2.12 0.14 Ma

A

B

C

D

E

3.2 0.2 Ma


A

B

C

D

E

2.91 0.19 Ma


2.8 to 3.2 Ma

Sample UC FN-37

Melanephelinite

Ilha Rata, derrame basal

Ar-Ar ages made in two

WR fragments

Brisbane laboratory

Perlingeiro et al, 2013

Basanites from São José Island

Sample: MN-FN-807 - K-Ar WR - 8.13 ± 0.36 Ma

MN-FN-809 - K-Ar WR - 21.9 ± 0.8 Ma

Sample UC-FN-17

Alkali-basalt, São José Island

K-Ar WR – 9.49 ± 0.33 Ma

K-Ar WR - 9.38 ± 0.94 Ma

São Paulo laboratory

Cordani, 1970

ASSUMPTION vs. ASSESSMENTBrisbane laboratory – Perlingeiro et al. (2013)

Enseada da Caieira – Pyroclastic rocks of the Remedios

Formation, with a mafic dike in the forefront.

Enseada da Caieira

Enseada da Caieira

Pyroclastic deposits of the

Remedios Formation, with

abundant block and lapilli

of magmatic rocks, cut by a

trachyte dike

Morro do Pico - Phonolite dome, view from the South.

Morro do Pico

Quarry at Morro da Boa Vista – Porphyritic phonolite with columnar joints

Arquipélago de Fernando de NoronhaIlhas da parte setentrional

Morro Branco

Atalaia Beach

São José and Cuzcuz islands. – Basanite flow of the São

José Formation capped by the Caracas calcarenite.

Nepheline basanite with columnar joint systems

São José

Formation

Detail of the hexagonal section of the columnar joints

São José island

Northern plateau of

Quixaba Formation

Quarry – Transito Hotel

CAPIM AÇU - Superposed lava flows of the Quixaba Formation separated

by pyroclastic levels (indicated by white lines). - Melilite melanephelinite,

pyroxene melanephelinite and two olivine melanephelinite flows.

Dois Irmãos islets – Basanites of the Quixaba Formation.

Perlingeiro el al. (2013) – História geológica do vulcão de

Fernando de Noronha

Main hypotheses on the origin of the

Fernando de Noronha volcano

Oceanic fractures F.F.M. de Almeida ( 1955) - Geologia e Petrologia do Arquipélago de

Fernando de Noronha. - DNPM, Divisão Geologia e Mineralogia,

Monografia 13, 181p.

Hot spot and plume along the Fernando de Noronha RidgeU.G. Cordani et al. (2004) – Novas determinações de idade pelos

métodos K-Ar e Ar-Ar para o Arquipélago de Fernando de Noronha –

Revista da Fac. Ciencias, Maputo , Moçambique .

Regional magmatic anomaly in the lithospheric mantle G. Perlingeiro et al. (2012) - 40Ar/39Ar geochronology of the Fernando

de Noronha Archipelago and implications for the origin of alkaline

volcanism in the NE Brazil – Journal of Volcanology and Geothermal

Research.

Zonas de fratura no Atlântico equatorial

The convective cells are produced by instabilities in the limit between the thick

continental lithospheric (lithosphere depth of 160 km for Borborema Province)

and of 50 km for Fernando de Noronha Archipelago; Oliveira, 2008).

Illustration of the idea for a convective flux in small scale

(modified after EDS; Demidjuk et al., 2007).

FRACTURES

Branner, 1903

Almeida, 1955

Cordani, 1970

Gorini, 1981

LITHOSPHERIC MANTLE

Fodor et al., 2002

Galindo et al., 2006

Perlingeiro. 2010

Knesel et al., 2011

Perlingeiro et al., 2012

Lopes & Ulbrich, 2006, 2015

PLUMES

Morgan, 1983

Gerlach et al., 1987

Weaver, 1990

Ulbrich, 1993

Ulbrich et al., 1994

Maringolo, 1995

Lopes, 1997; 2002

Ulbrich & Lopes, 2000

Misuzaki et al., 2002

Rivalenti et al., 2000; 2007

Kogarko et al., 2001; 2007

Buikin et al., 2010

Cordani et al., 2003; 2004

Thank you!

Fernando de Noronha Umberto G. Cordani - Acquacon · F.F.M. de Almeida ( 1955) - Geologia e...

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