Which of the following would be an example of decreasing the lithostatic pressure under a volcano?

Lava flows stacking on top of one another to make a taller volcano.
Volcanic gas interacting with the rocks to make them weaker.
Violent shaking of the volcano due to large earthquakes.
A landslide that removes the top of a volcano.

Answer:

Lithostatic pressure, the stress exerted on a body of rock by surrounding rock, is pressure in Earth's crust somewhat analogous to hydrostatic pressure in fluids. Lithostatic pressure increases with depth below Earth's surface.

Explanation: Abstract

We use numerical models to study the mechanical stability of magma reservoirs embedded in elastic host rock. We quantify the overpressure required to open tensile fractures (the failure overpressure), as a function of the depth and the size of the reservoir, the loading by the volcanic edifice, and the pore fluid pressure in the crust. We show that the pore fluid pressure is the most important parameter controlling the magnitude of the failure overpressure rather than the reservoir depth and the edifice load. Under lithostatic pore fluid pressure conditions, the failure overpressure is on the order of the rock tensile strength (a few tens of megapascals). Under zero pore fluid pressure conditions, the failure overpressure increases linearly with depth (a few hundreds of megapascals at 5 km depth). We use our models to forecast the failure displacement (the cumulative surface displacement just before an eruption) on volcanoes showing unrest: Sinabung and Agung (Indonesia) and Okmok and Westdahl (Aleutian). By comparison between our forecast and the observation, we provide valuable constraint on the pore fluid pressure conditions on the volcanic system. At Okmok, the occurrence of the 2008 eruption can be explained with a 1,000 m reservoir embedded in high pore fluid pressure, whereas the absence of eruption at Westdahl better suggests that the pore fluid pressure is much lower than lithostatic. Our finding suggests that the pore fluid pressure conditions around the reservoir may play an important role in the triggering of an eruption by encouraging or discouraging the failure of the reservoir.

1 Introduction

The past decades have provided a wealth of observations of ground surface deformation before, during, and after volcanic eruptions using Global Positioning System (GPS), tiltmeters, strainmeters, or satellite radar interferometry (InSAR). Observed preeruption inflation ranges from a few centimeters prior to the 2006 Augustine eruption, Alaska (Cervelli et al., 2006) to several meters at Sierra Negra volcano, Galapagos Islands (Geist et al., 2008). An important question for hazard assessment is whether detected inflation is a precursor for an eruption (Biggs et al., 2014; Chaussard et al., 2013; Dzurisin, 2003; Moran et al., 2011). There are many observations of preeruptive inflation at basaltic volcanoes, for example, at Krafla and Grimsvötn in Iceland (Bjornsson et al., 1979; Ewart et al., 1991; Lengliné et al., 2008; Reverso et al., 2014; Sturkell et al., 2006), Kilauea in Hawaii (Dvorak & Dzurisin, 1993), Fernandina in the Galapagos Islands (Bagnardi & Amelung, 2012), Axial Seamount in the Pacific ridge (Nooner & Chadwick, 2009), and Okmok in Alaska (Lu et al., 1998, 2010). For several andesitic and dacitic volcanoes arc-wide, InSAR surveys have documented preeruptive inflation (Chaussard & Amelung, 2012; Chaussard et al., 2013; Lu & Dzurisin, 2014; Pritchard & Simons, 2002; 2004). In contrast, other volcanic systems can show unrest in form of ground deformation, earthquakes swarms, large heat, and gas emissions for months to decades without eruption (Acocella et al., 2015; López et al., 2012; Lowenstern et al., 2006; Martí et al., 2013; Newhall & Dzurisin, 1988). This is the case of many silicic caldera volcanoes such as Long Valley (Hill, 1984; Newman et al., 2006), Santorini (Newman et al., 2012; Parks et al., 2012), Yellowstone (Chang et al., 2007; Wicks et al., 2006), Campi Flegrei (Amoruso et al., 2007; Beauducel et al., 2004; Di Vito et al., 1999; Gottsmann et al., 2006; Lundgren et al., 2001; Orsi et al., 1999; Samsonov et al., 2014; Trasatti et al., 2008; Troise et al., 2007; Vilardo et al., 2009), or Laguna del Maule (Feigl et al., 2014; Le Mével et al., 2015).

The inflation of the ground surface in volcanic areas results from stress changes in the crust due to the accumulation of magma or the exsolution of gas inside reservoirs or due to the propagation of magma through intrusions or conduits. Such surface displacements are often modeled at first order by analytical solutions such as point pressure sources (Mogi, 1958), finite spherical sources (McTigue, 1987), or dislocations (Okada, 1985) embedded in an elastic half-space. In a case by case approach, more realistic models based on numerical techniques have been also developed to better explain volcanic ground deformation. Such models can take into account the rheology of the crust, the heterogeneities of the rock properties and the topography of the volcano (Currenti et al., 2010; Del Negro et al., 2009; De Natale et al., 1997; Geyer & Gottsmann, 2010; Ronchin et al., 2015).

need the answer please lol

Discussion Topic
Natural disasters plague all areas of the world. In North America, the western coast of the United States experiences earthquakes, while the interior of
the country is at risk for tornados. Areas of East Asia endure typhoons. Volcanic eruptions threaten places as far apart as Italy, Hawaii, Chile, and the
Congo. What causes certain disasters to occur in certain areas? Which of the physical factors that you've studied impact the development of natural
disasters the most?

Each of the following can be a result of a large population growth except __________.
A.
a decrease in taxes
B.
food shortage and famine
C.
an increased health care cost
D.
more expensive public education

China’s policy of punishing people who choose to have more than one child could be considered a violation of __________.
A.
civil law
B.
human rights
C.
property rights
D.
international law

Which event of the 1800s led to increased interest in the colonization of Africa?
A. the Industrial Revolution
B. World War I
C. World War II
D. the American Revolution

3. If the measure of angle <3= 104°, list the
measures of all other angles. (use the
diagram for #3-4)

What is most likely to be found at fracture zones?.

What causes convection currents to occur on earth?.

What plant originated in arabia and later became a major crop in brazil and columbia?.

The strongest type of opinion of the court is:
A. a concurring opinion
B. a unanimous opinion
C.a dissenting opinion
D.a split opinion

If two air masses with different temperatures or humidity levels meet, they do not immediately mix or blend. Instead, a line or boundary forms between them. This boundary is called a front. Lesson 1. 08 Question 3 options: True False.

Define social, economic and environmental factors

Why are areas along the west coast of california cooler than you would expect for their latitude?.

In the figure, AB || CD and ∠EIJ ≅ ∠GJI.



Complete the following statements to prove that ∠IKL and ∠JLD are supplementary angles.

It is given that ∠EIJ ≅ ∠GJI.

Also, ∠EIJ ≅ ∠IKL and ∠GJI ≅ ∠JLK, as they are corresponding angles for parallel lines cut by a transversal.

By the definition of congruent angles, m∠EIJ = m∠GJI, m∠EIJ = m∠IKL, and m∠GJI = m∠JLK.

So, m∠IKL = m∠JLK by the
.

Angle JLK and ∠JLD are supplementary angles by the
, so m∠JLK + m∠JLD = 180°.

By the
, m∠IKL + m∠JLD = 180°.

Therefore, ∠IKL and ∠JLD are supplementary angles by definition.

At 180 degrees longitude, the __________ represents the point at which the Eastern and Western Hemispheres experience different days. A. Equator B. Prime Meridian C. Tropic of Cancer D. International Date Line Please select the best answer from the choices provided. A B C D.

What property of the crust allowed it to form as the exterior of earth?.

What is the best example of an interaction among the biosphere atmosphere and hydrosphere.

NEED HELP NOW


Which Western European nations are unlikely to have large commercial fishing industries?

Help, please... Brainliest if right thank you :))

What is the principal advantage of a flat map over a round globe?

When tornadoes pass through regions, they can strip the land down to bare soil. Exposing this bare soil could lead to increased —.

Intrusive and extrusive igneous rocks are classified based on what criteria?.

what is the difference between an oceanic crust and oceanic plate? & what is the difference between a continental crust and a continental plate? my teacher keeps using them referring to the same thing and i get confused?

What is the name of a brazilian treat made from cheese and guava?.

what type of climate is experienced in the North Western part of Europe? what is the human response for the typical climate for this region?​

What is the best application to chart the average temperature for the year?.

It is a cold winter day in New York City. The air temperature is below freezing in and below the clouds. What is the most likely form of precipitation?.

30 POINTS PLZ PLZ PLZ HELP !!!!!!!!

1. What is a democracy ?
A) system of government in which people hold power
B) system of government in which a monarch holds power
C) system of government in which representitives hold power

2. what is the main difference between a pure democracy and a republic?
A) in a republic,people vote directly on laws, but in a democracy, people elect represenitives who make laws.
B) in a democracy, people vote directly on laws, but in a republic, people elect representitives who make laws.
C) in a republic, people have no representasion,but in a democracy, people have represenitives who act for them.

3. which is an example of a democratic republic?
A) iran
B) saudi arabia
C) united staes

4. how is britains modern parliamentary system similar to a republic?
A) desicion makers are chosen by the monarch
B) Decision makers are elected by the citizens
C) desision makers are appointed by the upper class

5. how are democracys and dictatorships different?
A) in a democracy, people have a say in government,while in dictatorship they do not.
B) in a dictatorship, people elect a leader , while in a democracy they elect representatives.
C) in a democracy , people elect their leaders , while in a dictatorship they only elect representatives.

6. how are dictatorships and totalitarian governments related ?
A) both dictatorships and totalitarian governments have kings
B) a dictatorship is the opposite of a totalitarian government
C) a totalitarian government is an extreme form of dictatorship

7. which is an example of a dictatorship?
A) south korea
B) north korea
C) iran

8. how are parliamentary monarchies and constitutional monarchies similar?
A) both have monarchs whose power is restricted some way.
B) both have a document that sets out limits to the monarchs power
C) both have monarchs who do not have to abide by any laws or polices

9.in a theocracy, which person is most likely to hold poilitical power ?
A) buisness leader
B) elected leader
C) religious leader

10. which is considered a theocracy ?
A) cuba
B) iran
C) finland

Where did Thomas Elkins go to school and do you make it to where you can put as a 5 point?

(GIVE VERY SHORT ANSWER)
Define immigration​