1

PITON DE LA FOURNAISE

Country: France

Subregion Name: Western Indian Ocean

Volcano Type: Shield volcano

Volcano Status: Historical

Last Known Eruption: 2010 

Summit Elevation: 2632 m8,635 feet

Latitude: 21.231°S 21°13'51"S

Longitude: 55.713°E55°42'45"E

9/13/2010

Manzoni Patrick

2

Eruptive characteristic:• Central vent eruption• Radial fissure eruption• Explosive eruption• Lava flows• Debris Avalanche• Lava lake eruption• Flank (excentric) vent• Phreatic explosion

3

frequency of duration activity since 1844

020406080

100

0 1 2 3 4

duration, Years

Freq

uenc

y

• WE CAN SAY, HOWEVER THAT FOR THIS PERIOD, THE DURATION OF ERUPTIONS IS GENERALLY SHORT

• 92 ERUPTIONS TAKE PLACE WITH DURATION LESS OF 1 YEAR.

DURATION OF ERUPTI

ONS

FREQUENCY

SINCE 1844

0 92

1 12

2 1

3 1

4 0

frequency of duration activity

0

50

100

150

0 1 2 3 4 5 6

duration, Years

Freq

uenc

y

DURATION OF ERUPTI

ONFREQUEN

CY

0 132

1 25

2 4

3 5

4 2

5 3

6 0

DURATIONS OF HISTORICAL ERUPTIONS

4

DURATION ERUPTION

0

1

2

3

4

5

6

2009

2001

1981

1964

1951

1938

1925

1907

1897

1869

1849

1830

1813

1794

1772

1734

1640

2800-

years

dura

tion

year

s

Serie1

Media Mobile su 2 per.(Serie1)

DURATIONS OF HISTORICAL ERUPTIONS

• POSSIBLE CYCLE OF ERUPTION DURATION, WITH 3 PEAKS:1. 16402. 18303. 1985

• TIME INTERVAL OF 150 YEARS

5

VOLUME OF EMITTED LAVA

0

50000000

100000000

150000000

200000000

2009

2002

1991

1976

1961

1951

1943

1931

1920

1904

1897

1874

1858

1845

1824

1813

1797

1784

1766

1721

1640

-179

0

YEARS

VOLU

ME

(m3)

Serie1

ERUPTIVE CYCLES AND VOLUMES OF MAGMA EMITTED

• WE CAN DISTINGUISH 3 MAJOR CYCLES FOR THE LAST 70 YEARS:

1. 1931 WITH 0,05 m3/s OF MEAN OUTPUT2. 1985 WITH 0,1 m3/s OF MEAN OUTPUT3. 2006 WITH 1,3 m3/S OF MEAN OUTPUT

VOLUME(M3/s) CYCLES

0.04682811 1° CYCLE

0.096500644 2°CYCLE

1.290250732 3°CYCLE

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RELATION BETWEEN DURATIONS OF ERUPTIONS AND PERIODS OF INACTIVITYrelation of duration and period of inactivity

0

0.5

1

1.5

2

0.5 1

duration, years

repo

se b

efor

e, y

ears

Serie1

• THE DURATION OF AN ERUPTIONS HAS A DIRECT INFLUENCE ON THE DURATION OF THE FOLLOWING PERIODS OF INACTIVITY

1. <6 MONTHS < 1 YEARS2. >6 MONTHS > 1 YEARS

relations between time years and period of inactivity

012345

2000 1900 1800 1700

time interval, yearsre

pose

bef

ore,

ye

ars

Serie1

• THE PERIOD OF INACTIVITY DECREASE TOWARDS THE PRESENT EPOCH

• MORE FREQUENT ERUPTION

frequency of eruption

y = 0.0663x - 87.729R2 = 0.3146

0

10

20

30

40

50

60

70

1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100

YEARS

erup

tion

num

ber

Serie1

Lineare (Serie1)

7

INACTIVITY PERIODSinactivity periods

y = 139.78e0.0158x

R2 = 0.2243

1

10

100

1000

10000

100000

1000000

200920021991197619611951194319311920190418971874185818451824181317971784176617211640-179

years

repo

se b

efor

e,da

ys Serie1Espo. (Serie1)

inactivity periods

y = 139.78e0.0158x

R2 = 0.2243

0100000200000300000400000500000600000700000800000

1 12 23 34 45 56 67 78 89 100 111 122 133 144 155 166

points

days Serie1

Espo. (Serie1)

inactivity periods

y = 139.78e0.0158x

R2 = 0.2243

1

10

100

1000

10000

100000

1000000

0 10 20 30 40 50 60 70 80 90 100

110

120

130

140

150

160

170

180

points

days

Serie1Espo. (Serie1)

• THERE’S A DOWNWARD TREND OF THE REPOSE TIME

• AGREE WITH THE INCREASED FREQUENCY OF ERUPTION

• AGREE WITH THE AVERAGE VALUES OF PREVIOUS SLIDE

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"VEI" DURING ERUPTIVE HISTORY

0123456

2009

2001

1981

1964

1951

1938

1925

1907

1897

1869

1849

1830

1813

1794

1772

1734

1640

-2800

YEARS

VEI

VEI (MEAN)

YEARS

0.846154 2000

1.484375 1900

1.04 1800

1.25 1700

1.666667 1600

MEAN VEI

y = 0.1407x + 0.8354R2 = 0.4544

0

0.5

1

1.5

2

2000 1900 1800 1700 1600

years

VEI Serie1

Lineare (Serie1)

VOLCANIC EXPLOSIVITY INDEX

FREQUENCY "VEI"

0

20

40

60

80

100

0 1 2 3 4 5

VEI

FREQ

UEN

CY

• WE CAN NOTE, OVER THE YEARS, THE PREDOMINANT VALUE OF “VEI” IS 2

• PROBABLE ERUPTION CYCLE..?

• DOWNWARD TREND OF VOLCANIC EXPLOSIVITY INDEX

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CONCLUSION: FORECASTING VOLCANIC ERUPTIONS

• WE CAN DISTINGUISH THREE MAJOR VOLCANIC CYCLES DURING LAST 70 YEARS. THE THIRD IS STILL IN PROGRESS.

• EACH CYCLE BEGAN WITH A HUGE OUTPOURING OF OCEANITE MAGMA.

• THE DURATION OF AN INACTIVE PERIOD IS LINKED WITH THE DURATION OF PREVIOUS ERUPTION (AND MAYBE WITH THE VOLUME OF MAGMA EMITTED DURING PREVIOUS ERUPTION).

• WE CAN DISTINGUISH ONE MAJOR VOLCANIC CYCLE OF DURATION IN THE LAST 370 YEARS.

• A FUTURE FORECAST NEED ADDITIONAL DATA, SEISMIC DATA, INSTRUMENTS FOR MONITORING OF GAS EMISSION, ECC.