Calderas – a selective introduction

Slides:

Advertisements

Similar presentations

The Nature of Volcanic Eruptions

Advertisements

Volcanoes Lab 5.

By: David P. Hill, Roy A. Bailey, and Alan S. Ryall

Volcanoes: eruptive style and associated landforms

Volcanoes WHAT IS A VOLCANO? A volcano is an opening in the earth’s crust which allows molten rock from beneath the crust to reach the earth surface. The.

Unit 6-3: Types of Volcanoes. What is a volcano? A volcano is a spot in the Earth’s crust where magma can reach the surface.  It is named from the Roman.

THE LANGUAGE OF THE EARTH – PART I IGNEOUS ROCKS.

Volcanic Hazards p , web reading

Volcanoes. l Evidence that we live in an active planet l The gods of the underworld l Millions of people live near active volcanoes –The greatest geological.

Ch 12 Volcanos.

Chapter TWELEVE Volcanoes.

VOLCANOES. What is a volcano? Areas of earth’s surface through which magma and volcanic gases pass Magma flows from volcanoes transfer heat and thermal.

Volcano Types and Formation

Volcanic eruptions Factors that determine the violence of an eruption

Effects of Volcanic Eruptions. Volcanic Eruptions and Climate Change Volcanic ash and gases spread throughout the atmosphere, they can block enough sunlight.

VOLCANISM 80% of the earths crust is composed of volcanic rocks Volcanism: the process by which magma from the interior of the earth rises through the.

What happens after a supervolcano erupts and a caldera collapses ?

The term "supervolcano" implies an eruption of magnitude 8 on the Volcano Explosivity Index, meaning that more than 1,000 cubic kilometers (240 cubic miles)

Volcanic Eruptions. Mafic Lava  Dark colored  Rich in magnesium and iron  Formed from oceanic crust  Cools rapidly.

The role of impact structures in localizing explosive volcanism on a contracting planet: Mercury Rebecca J. Thomas*, Dave A. Rothery, Susan J. Conway,

Field evidence, experiments, modeling

Chapter 12: Volcanoes!. Volcanoes and Earth's Moving Plates A volcano is an opening in Earth that erupts gases, ash and lava. Volcanic mountains form.

A summary lecture on two long-lived eruptions, and how we as scientists might respond to such events.

Calderas – a selective introduction

Volcanoes By: Cody and Jennifer. When a volcano erupts, it either has a lava flow or pyroclastic flow Magma that flows onto earth’s surface is called.

Volcanoes 2. Shield Volcanoes: broad at the base with gently sloping sides Form from: quiet eruptions Example: Hawaiian Islands Types of Volcanoes.

Understanding Earth Chapter 12: VOLCANOES Grotzinger • Jordan

Supervolcanoes and calderas !. The Volcanic Explosivity Index- how big is a supereruption ? VEI- 5 Plinian, Mt St Helens VEI 3 Vulcanian Montserrat VEI.

Chapter 9 Section 2 Volcanoes. Effects of Volcanic Eruptions In 1816, Chauncey Jerome, a resident of Connecticut, wrote that the clothes his wife had.

3. Calderas Dan Barker March 2009 Ngorongoro, Tanzania.

THE NATURE OF VOLCANIC ERUPTION

Learning Objectives I can explain how volcanic eruptions can affect climate. I can explain how volcanic eruptions can affect climate. I can compare the.

Volcanoes Effect on Earth. An Explosive Impact Flows and Fallout Characteristics ◦ Can flow like an avalanche ◦ Can mix with water to form mudslides ◦

Chapter 9 Volcanoes.

Volcanoes. Ag Earth Science – Chapter 10.1 viscosity A measure of a fluid’s resistance to flow.

Volcanoes. Volcanoes Pyroclastic is a term used to describe any materials blasted out of a volcanic eruption The particles from smallest to largest are:

What is a volcano? Volcanoes are formed when magma from within the Earth's upper mantle works its way to the surface. At the surface, it erupts to form.

Volcanoes Erupting with fun!.

Intro to Volcanoes.

Unit 4 Lesson 4 Volcanoes Copyright © Houghton Mifflin Harcourt Publishing Company.

Unit 4 Lesson 4 Volcanoes.

VOLCANOES Their Products Peter Copley Feb 04.

California Standards 3.b.,c. & f.

Mrs. Gordon Earth Science Tuesday, July 03, 2018

OBJECTIVES: Types of Magma Anatomy of a Volcano Types of Volcanoes

Geology Notes Part 9 1.

Nature of Volcanic Eruptions

Earth’s Materials and Processes-Part 11 Volcanoes!

Volcanoes Ch. 9.

Unit 4 Lesson 4 Volcanoes Copyright © Houghton Mifflin Harcourt Publishing Company.

Volcanic Eruptions.

Geology Notes Part 8 1.

Ch.6, Sec.2 - Effects of Volcanic Eruptions

Unit 4 Lesson 4 Volcanoes Copyright © Houghton Mifflin Harcourt Publishing Company.

Quiz The most important factor affecting the size of crystals in an igneous rocks is the: A. Water pressure around the magma B. Rate of cooling C. Size.

Why do I always take the time to read these when all I do is wonder why I read these …. And now I’m reading this again! Geez … there I go, reading this.

Volcanic Eruptions.

Volcanoes Earth Science Chapter 10.

Locations of Volcanoes

3.3 Plates Move Apart Learn about: Different types of plate boundaries

This is a map of Long Valley caldera below

Presentation transcript:

Calderas – a selective introduction

What is a caldera? A caldera is a surface depression formed by draining a subsurface magma reservoir Once a magma chamber has drained sufficiently, its roof can no longer be supported, so it collapses into the reservoir Draining of the reservoir can occur by subsurface intrusion (basaltic systems) or by explosive venting (silicic systems) (can you think of some examples?) The structural rim and topographic rim of a caldera are different Calderas are filled with breccia and pyroclastic rocks The caldera floor can be coherent or broken up into many pieces Lipman 1997 BV

Smith and Bailey’s caldera cycle

Caldera-related magma reservoirs How are they sustained? What is their physical nature and rheology? How do they evolve over time? National Park Service

Triggers and causes of caldera eruptions Changes in the physical state of the magma Replenishment Overpressure Role of magmatic-hydrothermal fluids Any other ideas ?

Styles of caldera collapse Effects upon intracaldera ignimbrite and cooling Role of regional structures Lipman 1997 BV

Links between subsidence processes and magma chamber processes Mixing and stirring of magma Single blocks vs. multiple blocks Temporally increasing magma diversity Intensification of eruptions Kennedy et al 2008 Nature Geosci

Calderas at stratovolcanoes Crater Lake Pinatubo

Basaltic calderas Miyakejima 2000 Sandbox experiments - Roche et al 2000 JGR

Miyakejima 2000 degassing caldera formation complete Kazahaya et al Geology

Restless silicic calderas Long Valley (USA) Yellowstone (USA) Rabaul (Papua New Guinea) Campi Flegrei (Italy) Maule (Chile) Role of regional structure Calderas as pull-apart basins USGS

Resurgence and associated activity Styles Mechanisms Timing of collapse and resurgence Hydrothermal systems Ore deposits Smith and Bailey 1968

Global impact of caldera-related super-eruptions Atmosphere Land surface Sea surface Vegetation