أنواع الثورات البركانية

Mosaic of some eruptive structures formed during volcanic activity: An eruption column from a Plinian eruption, Pahoehoe lava flow from a Hawaiian eruption, and a lava arc from a Strombolian eruption.

آليات الثورات البركانية

Diagram showing the scale of VEI correlation with total ejecta volume.

مؤشر انفجارية البرجان

Volcanic eruptions by VEI index

VEI	Plume height	Eruptive volume *	Eruption type	Frequency **	Example
0	<100 m (330 ft)	1,000 m³ (35,300 قدم³)	Hawaiian	Continuous	Kilauea
1	100–1,000 m (300–3,300 ft)	10,000 m³ (353,000 قدم³)	Hawaiian/Strombolian	Months	Stromboli
2	1–5 km (1–3 mi)	1,000,000 m³ (35,300,000 قدم³) ^†	Strombolian/Vulcanian	Months	Galeras (1992)
3	3–15 km (2–9 mi)	10,000,000 m³ (353,000,000 قدم³)	Vulcanian	Yearly	Nevado del Ruiz (1985)
4	10–25 km (6–16 mi)	100,000,000 m³ (3.53×10⁹ قدم³)	Vulcanian/Peléan	Few years	Galunggung (1982)
5	>25 km (16 mi)	1 km³ (0.24 ميل³)	Plinian	5–10 years	Mount St. Helens (1980)
6	>25 km (16 mi)	10 km³ (2 ميل³)	Plinian/Ultra Plinian	1,000 years	Krakatoa (1883)
7	>25 km (16 mi)	100 km³ (20 ميل³)	Ultra Plinian	10,000 years	Tambora (1815)
8	>25 km (16 mi)	1,000 km³ (200 ميل³)	Ultra Plinian	100,000 years	Lake Toba (74 ka)
* This is the minimum eruptive volume neccessary for the eruption to be considered within the category. ** Values are a rough estimate. Exceptions occur. † There is a discontinuity between the 2nd and 3rd VEI level; instead of increasing by a magnitude of 10, the value increases by a magnitude of 100 (from 10,000 to 1,000,000).

ثورات الصخور المنصهرة

Magmatic eruptions produce juvenile clasts during explosive decompression from gas release. They range in intensity from the relatively small lava fountains on Hawaii to catastrophic Ultra Plinian eruption columns more than 30 km (19 mi) high, bigger than the AD 79 eruption that buried Pompeii.

Hawaiian

Diagram of a Hawaiian eruption. (key: 1. Ash plume 2. Lava fountain 3. Crater 4. Lava lake 5. Fumaroles 6. Lava flow 7. Layers of lava and ash 8. Stratum 9. Sill 10. Magma conduit 11. Magma chamber 12. Dike) Click for larger version.

Ropey pahoehoe lava from Kilauea, i.

Strombolian

Diagram of a Strombolian eruption. (key: 1. Ash plume 2. Lapilli 3. Volcanic ash rain 4. Lava fountain 5. Volcanic bomb 6. Lava flow 7. Layers of lava and ash 8. Stratum 9. Sill 10. Magma conduit 11. Magma chamber 12. Dike) Click for larger version.

An example of the lava arcs formed during Strombolian activity. This image is of Stromboli itself.

Vulcanian

Diagram of a Vulcanian eruption. (key: 1. Ash plume 2. Lapilli 3. Lava fountain 4. Volcanic ash rain 5. Volcanic bomb 6. Lava flow 7. Layers of lava and ash 8. Stratum 9. Sill 10. Magma conduit 11. Magma chamber 12. Dike) Click for larger version.

Tavurvur in Papua New Guinea erupting.

Peléan

Diagram of Peléan eruption. (key: 1. Ash plume 2. Volcanic ash rain 3. Lava dome 4. Volcanic bomb 5. Pyroclastic flow 6. Layers of lava and ash 7. Stratum 8. Magma conduit 9. Magma chamber 10. Dike) Click for larger version.

Pyroclastic flows at Mayon Volcano, Philippines, 1984.
The lava spine that developed before the 1902 eruption of Mount Pelée
Mount Lamington following the devestating 1951 eruption.

Plinian

Diagram of a Plinian eruption. (key: 1. Ash plume 2. Magma conduit 3. Volcanic ash rain 4. Layers of lava and ash 5. Stratum 6. Magma chamber) Click for larger version.

21 April 1990 eruptive column from Redoubt Volcano, as viewed to the west from the Kenai Peninsula.

Phreatomagmatic eruptions

Surtseyan

Diagram of a Surtseyan eruption. (key: 1. Water vapor cloud 2. Compressed ash 3. Crater 4. Water 5. Layers of lava and ash 6. Stratum 7. Magma conduit 8. Magma chamber 9. Dike) Click for larger version.

Surtsey, erupting 13 days after breaching the water. A tuff ring surrounds the vent.
The fissure formed by the 1886 eruption of Mount Tarawera, an example of a fracture zone eruption.
Hole-in-the-Ground, a large maar in Oregon.

Submarine

Diagram of a Submarine eruption. (key: 1. Water vapor cloud 2. Water 3. Stratum 4. Lava flow 5. Magma conduit 6. Magma chamber 7. Dike 8. Pillow lava) Click to enlarge.

Subglacial

A diagram of a Subglacial eruption. (key: 1. Water vapor cloud 2. Crater lake 3. Ice 4. Layers of lava and ash 5. Stratum 6. Pillow lava 7. Magma conduit 8. Magma chamber 9. Dike) Click for larger version.

Herðubreið, a tuya in Iceland.

Phreatic eruptions

انظر أيضا

قائمة البراكين الثائرة الحالية
أنواع البراكين
أكبر الثورات البركانية في العالم

المصادر

^ خطأ استشهاد: وسم <ref> غير سليم؛ لا نص تم توفيره للمراجع المسماة hvw-vei
^ خطأ استشهاد: وسم <ref> غير سليم؛ لا نص تم توفيره للمراجع المسماة volcash

قراءات إضافية

. University of California Press. 1985. p. 258. ISBN . Retrieved 5 August 2010. Unknown parameter |coauthors= ignored (|author= suggested) (help)
"A transient model for explosive and phreatomagmatic eruptions". Journal of Volcanology and Geothermal Research. Volcanic Eruption Mechanisms - Insights from intercomparison of models of conduit processes. 143 (1–3): 133–151. May 2005. doi:10.1016/j.jvolgeores.2004.09.014. Retrieved 5 August 2010. Unknown parameter |coauthors= ignored (|author= suggested) (help)
Pyle, D. M. (January 1989). "The thickness, volume and grainsize of tephra fall deposits". Bulletin of Volcanology. 51 (1): 1–15. doi:10.1007/BF01086757.
"Quantitative shape measurements of distal volcanic ash" (PDF). Journal of Geophysical Research. 108 (B10). 28 October 2003. doi:10.1029/2001JB000818. Unknown parameter |coauthors= ignored (|author= suggested) (help)
William Henry Mathews (September 1947). Tuyas," flat-topped volcanoes in northern British Columbia". American Journal of Science. 245: 560–570.. This is the original landmark paper by William Henry Mathews that first described tuyas and subglacial eruptions.