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The full question is: Is it possible that the recent, successive, long droughts from Australia to the West Coast of both American continents are signs of epic crust failure?

The question is aimed specifically at the possible link between droughts at those specific areas and the weakening/loosening of lateral stress between tectonic plates.

The reasoning is based on the following observations:

  1. The crust is not rooted in the mantle, and is cut in numerous crustal plates. Tectonic plates are held in place like an arch, so the gravity and lateral stress and friction are the main forces holding them up. Mantle flow provides uneven support to continental plates and is actually the main destabilizing force according to current theories.

  2. Based on the idea above, if humans dig up too much underground materials around the fault lines, the edges of the fault lines are weakened: there is less material to keep up adequate lateral stress. Then, the soil around the softer/weaker side of the fault will deform and be compacted, or fail and result in earthquake. Deformation/compaction and fault failure do happen naturally too, but humans may have extracted too much underground resources for the natural healing process to catch up with the rate of weakening at the edges. It is known that the fault of the West Coast is lacking stress and the soil is deformed in the Amos et al. (2014) study. If this keeps up, the arch structure of the crust will crumble down catastrophically, and in chain reaction too. And it doesn't take "much" edge weakening to fail an arch.

Additional information: The Amos study says that California lost 160 KM^3 of groundwater in the past 150 years. Now, add the amount of oil extracted. Then, add the amount of oil, water, minerals that are extracted along the West Coast of North and South America, Australia, Japan, South East Asian Islands. This should give some idea of how big are the holes human dug underground.

  1. The scenario may correspond with the Pacific plates. There are numerous oil, and water extracting operations all around the Pacific. After decades of intensive and continuous resource extractions, it may be showing terminal signs of the natural healing process failing to catch up with the rate of weakening at the edges. First, there are quite a few very strong earthquakes concentrated in the last ten years (http://earthquake.usgs.gov/earthquakes/world/10_largest_world.php). This alone may be trivial since the Pacific Ring of Fire is well known to churn out earthquakes. However, combined with the recent persistent droughts of Australia, Chile, US (especially California), and this year, Canada, the situation may be really concerning.

  2. Droughts alone can be caused by weather patterns. Climate change can cause it too, but it is a global factor, as opposed to more localized factor such as weather patterns. However, I think that underground processes can also cause drought. Aquifers can store a lot of heat, so the lack of underground water means that the geothermal energy will dissipate into the surrounding soil, basically slowly baking it. Less water also means that the soil is more prone to compression. Compression, especially continuous, even if it's slow, also generates heat. Oil reservoirs are also similar, but since oil is more reactive to heat by transforming into gas, and continuously extracted by humans, their pore pressure varies more. The presence of oil reservoirs around the fault lines may serve as springs. By extracting oil/gas, humans lessen the expansion force of those liquid and gas and reduce the pore pressure, which stabilizes the fault line. But in the long term, as is the case now, the reality is that there will be not enough oil to provide adequate pore pressure/lateral stress/counter-compression force. This may be the cause of the recent frequent strong earthquakes; the plates are loosening. Eventually, all the edges of the Pacific ring will all fail in an epic catastrophe, as the arch structure of the crust crumbles. Also, by removing oil, it liberates more space for gas to form. Gas is more compressible and heated by compression; it is another source geothermal heat. It is like a bike air pump/air suspension system. The idea is that the excess of geothermal energy causes surface water to dry out faster.

  3. Another possibility is that the fault line of the West American continent is already caving in and is dipping deeper/entering into more contact with the mantle. The mantle is a way stronger source of heat, and without adequate of underground heat absorbers, the surface soil becomes baked. I think that it's also the cause of the Blob (https://en.wikipedia.org/wiki/The_Blob_%28Pacific_Ocean%29). The heat of the soil is escaping into the ocean, forming the Blob. Combined with El Nino, it worsens the drought.

In summary, humans have dug up resources around active fault lines of the Pacific for more than a century. The weakened soil/plate edges lead to excessive geothermal energy affecting the surface.

So yeah, in the end, is it possible that the recent droughts are signs of epic crust failure?

Please kindly point out if my observation/logic makes sense and/or may correspond with reality.

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closed as unclear what you're asking by arkaia, farrenthorpe, Fred, EnergyNumbers, Peter Jansson Oct 15 '15 at 15:07

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ Is this a question? I am not sure it fits the guidelines earthscience.stackexchange.com/help/dont-ask $\endgroup$ – Isopycnal Oscillation Oct 15 '15 at 2:07
  • $\begingroup$ It looks like I need to word it better. $\endgroup$ – Teki Haken Oct 15 '15 at 2:31
  • $\begingroup$ I pulled this wall of text from email, so the wording does not sound much like a question. However, I do want to know the answer. $\endgroup$ – Teki Haken Oct 15 '15 at 2:49
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    $\begingroup$ "Continental plates are held in place like an arch"... what? Aren't they held in place more like a tile in soft grout? It's not like there is a big air space underneath them. The mantle is a solid/extremely viscous fluid, not liquid... I suspect that there are lot more unsupported assumptions further down here that make this question quite difficult to deal with (e.g. the "concentrated volcanos" statement doesn't seem very well supported [low R2]). Perhaps you should split it up into separate questions? $\endgroup$ – naught101 Oct 15 '15 at 4:05
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    $\begingroup$ @TekiHaken He meant earthquakes $\endgroup$ – Isopycnal Oscillation Oct 15 '15 at 6:57
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Is it possible that the recent droughts are signs of epic crust failure?

No. Even though your 5 points do not make much sense, I'll try to answer it anyway.

  1. There are no continental plates. There are lithospheric plates, consisting of both continental crust and oceanic crust. While it is true that arches in construction (buildings and bridges) are held "up" by lateral stress and gravity, lithospheric plates are not arches. Directly below the crust there exists a mantle, made out of a ductile, yet solid, material. The crust can't just "fall down".

  2. Movements that occur along plate boundaries are controlled by tectonic forces much larger than anything that we humans can even think of affecting. While it is true that some seismic activity can be explained by extraction of resources, these are usually up/down movements. Thus, extracting oil from the Los Angeles area will not cause the movement along the San Andreas fault to move any slower or faster.

  3. So yes, there are large earthquakes, including recently, in the ring of fire. I don't understand how is this supposed to be related to droughts. There earthquakes are controlled by forces deep down in the Earth. Furthermore, the plate boundaries are under kilometres of ocean water. Whether or not there is rain on the continents is irrelevant.

  4. Gas is not formed simply by evaporation of oil. Releasing pressure does not turn oil to gas. This is a long process that takes geological time spans. Deep water that may be affected by geothermal heat has long residence times - hundreds and thousands of years. A few years of drought will not do much for it. Most of the oil and gas are being produced in sedimentary basins, far away from plate boundaries. These have nothing to do with earthquakes near these fault lines. Even the fields that are somewhat close to fault boundaries - the amount of oil or gas that's actually in the ground is negligible relative to how much rock there is. It's not like there are lakes or pools of oil and gas. It's all in between the grains of whatever sedimentary rock is there (usually sandstone).

  5. The term you are looking for is subduction. Yes, there is some subduction activity (otherwise we wouldn't have volcanoes such as Mt St Helens). This is nothing new, and again, this has nothing to do with droughts.

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    $\begingroup$ @TekiHaken the link between droughts and crust goes no deeper than the surface characteristics. The presence of surface water (oceans, lakes, rivers, soil moisture, evapotranspiration), the surface terrain (hills, mountains, valleys, etc) and general atmospheric flows affect droughts. $\endgroup$ – casey Oct 15 '15 at 17:57
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    $\begingroup$ @TekiHaken: I think there are problems with scale here. The 5 points you present above all have some basis in reality, but I think the scale required for each of them to be relevant in this context is much larger than what is actually happening. Perhaps you could ask separate questions along the lines of "How much drying would a 0.1°C rise in crust temperature cause?" (I suspect that value is many orders of magnitude larger than what you're talking about), and "How much heat has human geological activity caused?" and "How much gas is produced by oil depressurisation?" $\endgroup$ – naught101 Oct 15 '15 at 22:59
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    $\begingroup$ @TekiHaken This isn't the right platform to attempt persuasive argumentation against an answer. Stack Exchange is a question & answer site, and is not a forum or discussion venue. It also appears you might be fishing for an answer you want since you seem to be very reluctant to listen to reasoning that doesn't fit with your view on the matter. I'll echo the comment above that you should try to understand the individual factors and ask narrowly scoped questions about them to help you reach that understanding. Welcome to the site. $\endgroup$ – casey Oct 16 '15 at 2:29
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    $\begingroup$ @teki: You won't get a satisfactory answer to this question. People are asking you to split it out into separate, smaller questions so that you will get satisfactory answers. $\endgroup$ – naught101 Oct 16 '15 at 5:56
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    $\begingroup$ @TekiHaken - Your last comment "[...] to let people have an easier time understanding the theory" concerns me. Are you asking a StackExchange type Question or are you promoting a theory by attempting to disguise it as a question? $\endgroup$ – O.M.Y. Dec 18 '15 at 3:02

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