
Geological Insights from Malaysia Airlines Flight MH370 Search - car
https://eos.org/project-updates/geological-insights-from-malaysia-airlines-flight-mh370-search
======
avar
I wondered what it would cost to get this detail for the entirety of the
ocean. They say they mapped an area the size of New Zealand, which is around
250k km^2. According to a quick Google search the total area of the oceans is
360 million km^2, and according to a Guardian article I found[1] the
subsurface search cost 180 million AU$.

    
    
        (360/0.25)*180 =~ 250 billion AU$
    

That's around 190 billion USD, not even 0.1 Iraq wars, and that's before
considering any economies of scale.

1\. [https://www.theguardian.com/world/2017/jan/17/malaysia-
airli...](https://www.theguardian.com/world/2017/jan/17/malaysia-airlines-
flight-mh370-search-called-off)

~~~
LeifCarrotson
It's futile to attempt to value things as fractions of a war. While typically
the dollar is a useful metric for the worth that society ascribes to
something, public opinion on the importance of the Iraq war and the federal
budget for the military are radically different.

The annual budget for the entire USGS is $1.2 billion. NOAA has a budget of
$5.6 billion. NASA has a budget of $19.5 billion. The NSF has a budget of
about $2 billion. If these agencies dropped everything else and invested
purely in this map, it would take about 5 years to create it.

Or, yeah, you could buy not even 0.1 Iraq wars with those 5 years, if that
sounded better...

~~~
stdbrouw
I'm not sure I understand: why is it futile to attempt to value things as
fractions of a war given that public opinion on that particular war is
divided?

~~~
krona
Because it's poor accounting. Given the scale of the US military and it's
annual expenditure just existing, to make a fair comparison you should at
least take account of the marginal cost of the war, not the total cost.

There is also the opportunity cost to take account of, but that's much harder
(impossible?) to put an accurate figure on.

~~~
xapata
I thought the figure provided was the marginal cost.

~~~
mikeash
It is, of course. Nobody is calculating the cost of the war as the defense
budget multiplied by the time. The cost includes about $750 billion in direct
appropriations for the war itself (separate from the overall defense budget),
plus numerous indirect costs such as additional medical care and disability
payments to veterans, replacement of destroyed equipment, and interest
payments due to increasing the national debt.

------
astrodust
That's an exponential increase in resolution, but it's also amazing how the
_gravity_ -derived maps fit in so well with the sonar-derived ones. That's
some serious validation of the gravity approach, as limited as it is.

~~~
wiredfool
Given that about 10% of the ocean has been mapped like this, I'd bet that
portion has been used as a calibration for the gravity based dataset.

~~~
jofer
The gravity-based methods require the ship track data as well -- they're not
fully independent methods. (i.e. not only are they calibrated to it, ship-
track bathymetry is actually half of the input data for gravity-derived
bathymetry.)

It's still really quite amazing how well it matches in an area that's pretty
far from dense ship-track bathymetry data.

------
daleroberts
Really nice article, my mind is always blown by all the cool shit we keep on
learning about our Earth.

And then the article became all the more sweeter when I realised that it all
this work was done by people I know at Geoscience Australia. Very cool.

~~~
aynsof
Hello from GA! If this sort of stuff is interesting to you, keep an eye out
at: [http://eos.ga.gov.au](http://eos.ga.gov.au)

And we've just started an engineering blog which might be of interest to the
HN crowd: [https://tech.ga.gov.au](https://tech.ga.gov.au)

~~~
daleroberts
Hello from ANU! I've actually been collaborating on a number of projects with
GA the last couple of years :-)

------
speps
Is the raw data available somewhere?

EDIT: found a lot more info (and videos) here :
[http://www.ga.gov.au/about/projects/marine/mh370-bathymetric...](http://www.ga.gov.au/about/projects/marine/mh370-bathymetric-
survey)

------
car
In light of how little we know, it's great to see that there are
philanthropists supporting oceanographic research, specifically a shout out to
Eric & Wendy Schmidt, [https://schmidtocean.org](https://schmidtocean.org).

------
qeternity
I am always amazed at how relatively little we know about the ocean floor.

------
Baeocystin
Fascinating. The reason for the mapping is tragic, but I hope some of the
families so affected can take some degree of solace from the knowledge gained
thus.

~~~
DaiPlusPlus
Cynically I imagine this data will be invaluable to energy companies looking
for potential new oil drilling sites - I'm not sure if I'd want my legacy to
be the continuation of fossil-fuels...

~~~
jofer
As a former exploration geologist on the petroleum side and marine
geophysicist on the academic side - No, this data isn't very useful for
petroleum exploration at all.

Most of the deep ocean basins have absolutely zero oil.

To create thermogenic hydrocarbons, you need thick sediments. You can make
methane biogenically without significant sediment cover, and that's important
sometimes, but you cannot make oil that way. Oil is what drives exploration
far away from population centers.

The abyssal plain you're seeing in that data is mostly exposed oceanic crust.
There's almost no sediment cover. No sediments --> no exploration potential.

There's one narrow continental fragment that could have significant sediment
cover. However, it's highly unlikely that that's prospective. (If you're
curious, I'm happy to elaborate, but it will take a bit of explanation.)

There is one way this data will be used for petroleum exploration. It aids our
understanding of the tectonic evolution of the area, which in turn aids
petroleum exploration. However, if you're going to take a moral stance against
that, you also need to a moral stance against every scientific advance in
every field. They all aid the oil industry indirectly. (Ditto for software.)

~~~
mikeash
Great comment, thanks for the information. I suspected that the deep ocean
wouldn't be good for oil, but only because it would be logistically difficult.

Why isn't there sediment cover in these areas? I would naively think that
you'd get some raining down as plants and animals die in the shallower depths.
Clearly that must not be the case, but why not?

~~~
jofer
In a nutshell, you're a long way from a sediment source. Most sediments by
volume come from erosion of the continents or other landmasses. There's a much
higher rate of deposition if you're near a continent (e.g. river deltas).

Additionally, oceanic crust is always very young geologically. It's
continually formed and destroyed (subducted). The ocean basins haven't had
much time to fill up with sediment, because oceanic crust is essentially a
conveyor belt.

\-----

So the short answer is: You're depositing things very slowly on something that
doesn't have much time for sediments to build up.

\-----

In a bit more detail, the sediments you get in the middle of the ocean are
either the initial volcanic-related sediments that were deposited as the
oceanic crust formed, or they're limited to "pelagic rain" (things near the
surface dying and very fine particles of clay) and some chemical sediments
(things that precipitate directly out of water).

Not only that, but a lot of the things that die and sink will dissolve below
about 2 Km water depth (see Carbonate Compensation Depth).

Therefore, deepwater depositional rates are very, very slow.

There's a very important exception, though -- Carbonates. If you start in
shallow water (say, due to a small sliver of continental crust), organisms in
the photosynthetic zone can produce huge amounts of carbonate sediments just
from their shells (e.g. coral reefs).

Under the right conditions, carbonates can keep growing and keep pace with the
subsiding crust. A good example of this is the Bahamas. You have several
kilometers of sediment made of nothing but what grew there and died. There are
some very significant oil fields in these sorts of "isolated platforms".

However, you need fairly unique conditions to get oil in the sort of isolate
carbonate platforms that develop far away from land. In most cases you'd find
out in the ocean basins, you won't have a source rock capable of generating
hydrocarbons beneath the pile of sediments that the carbonates produce.
Instead, the source rock is conveniently sitting out there in the deep water
where it's not buried deep enough to produce oil.

There's one other exception, and that's when you're near a volcano. Volcanoes
will happily produce lots of volcanic-related sediments. However,
volcaniclastic sediments almost never make good reservoirs (there are
exceptions) or seals, so even if you did generate oil in a narrow band around
a seamount, it would either leak out (no seal) or be trapped in something that
you can't get it out of (bad reservoir).

And there's the longer answer :)

~~~
mikeash
Delightful. Thanks so much for taking the time to write out the longer answer.
I think that "pelagic rain" is what I was referring to before, but I didn't
realize that the quantity was so low, or that subduction would keep it from
building up in most cases. Nor, of course, did I realize all of this other
great stuff.

------
darknoon
Does anyone know if the dataset is available publicly?

~~~
ajdlinux
According to
[http://www.ga.gov.au/about/projects/marine/mh370-bathymetric...](http://www.ga.gov.au/about/projects/marine/mh370-bathymetric-
survey/mh370-bathymetric-survey) "Data collected as part of the bathymetric
survey will be publicly released by Geoscience Australia in due course."

