Volcanoes on Mercury Solve 30-year Mystery (Via Volcano World)
A NASA spacecraft's first flyby of Mercury has yielded a wealth of information about the inner-most planet, some of which confirms volcanism occurred there, settling a longstanding debate.
Information about such planetary mysteries as Mercury's magnetic field and geological history also has flooded in.
"We're really pleased," said Sean C. Solomon of the Carnegie Institution of Washington, principal investigator for the MESSENGER probe. "[The data] gives us a lot to chew on."
MESSENGER (short for MErcury Surface, Space ENvironment, GEochemistry, and Ranging) made its debut flyby of Mercury on Jan. 14, passing about 124 miles (200 kilometers) over the planet's surface. The spacecraft's instruments took a closer look at the areas seen by the Mariner 10 mission in 1974 and 1975, which imaged about 45 percent of the planet's surface, as well as an additional 21 percent of the surface never before seen by a spacecraft.
In a collection of 11 papers detailed in the July 4 issue of the journal Science, mission scientists presented the preliminary findings of the initial flyby.
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3 comments:
That is very cool! I don't think there is an atmosphere on Mercury (stripped by solar wind), so I'll make the following prediction.
The gases must be getting launched into the vacuum of space where it is stripped away by solar wind, and the fluids must be mostly drizzling down forming alluvial-type sediments but some of it ought to be sputtered into unstable orbits, solidifying, and then reimpacting the planet somewhere else as small pebbles.
APOLOGY TO CAMERON SNOW
I owe an apology to Cameron Snow. After reviewing the below cited paper, it seems there are regions "[i]n areas such as the deepwater GOM, the geothermal gradient is quite low."
I was wrong to state catagorically that all "oceanic crust" has a high geothermal gradient.
This is the document that supports Cameron Snow's statement (conclusions provided below)
Geothermal Gradients and Subsurface Temperatures in the Northern Gulf of Mexico*
By
Joseph Forrest1, Ettore Marcucci1 and Paul Scott2
Conclusions
Equilibrium bottom-hole temperature data in the northern Gulf of Mexico is difficult to obtain, but the use of the large set of field-based sand data from the MMS supplemented by wells gives a valid regional picture of thermal trends in the basin. The interpreted pattern of BMLD300 (below-mudline depth to 300oF) values derived from geothermal gradients allows us to divide the northern Gulf into six temperature domains. Three domains on the shallow-water shelf areas have generally higher geothermal gradients and shallower BMLD300 values than those in the three deep-water domains. The shallowest BMLD300 values (and thus highest heat flow values) occur in the Texas shelf domain and appear to be related to the northeast-trending Corsair fault and possibly the extension of the San Marcos arch. The deepest BMLD300 values (and therefore the lowest heat flow values) occur in the Walker Ridge and Mississippi fan domains. The Mississippi fan pattern can be explained by rapid, thick sedimentation that has suppressed regional isotherms resulting in low surface heat flow.
Cameron Snow stated: "In areas such as the deepwater GOM, the geothermal gradient is quite low."
I relied on the follwoing paper and statement therein:
Tulane University Prof. of Petrology Stephen A. Nelson's paper, Structure of the Earth and the Origin of Magmas, where he says:
"The normal geothermal gradient is somewhat higher beneath the oceans than beneath the continents..."
So, in conclusion, I over-generalized and was wrong to cast aspersions on Cameron Snow's statement.
On a related note I stated "nowhere in the literature is there mention of a P-T cracking table for the "oil window."
The oil industry, as far as I'm aware, doesn't keep "P-T cracking table[s]" per se, but does keep track of the geothermal gradient for purposes related to the "oil window" theory.
My apology for my inacurrate assertions.
I hold others to the standard of the scientific method in discussion. I have to hold myself to the same standard as well.
The standard of the scientific method is to admit errors when conscious they have been made.
So, if I'm aware I was in error on some part of a discussion, it's up to me to acknowledge my error and apologize.
Thank you for your patience.
SQUARE ONE FOR OIL GEOLOGISTS IS THE "OIL WINDOW"
In recent debates with oil geologists on the scientific merits of the two competing theories of petroleum's origin, it's apparent that the "starting line" for oil geologists is to state the "oil window" corollary to fossil theory:
An oil geologist states: "...[The] principle that biogenic oil forms over several thousands of years during slow heating of temperatures up to 275 F. This heating process is what drives cracking."
Oil geologists will give various analogous descriptions.
Okay. So?
It's important to know that the "oil window" has two parts: "diagenesis" is the first half, and "catagenesis" is the second half.
The above description covers the catagenesis "second half" of the "oil window" corollary. That is, after organic detritus supposedly is converted into "kerogen," which generally consists of atomic weight and chemical structure as follows: C215H330, only then does "catagenesis" start.
"Diagenesis" is the label attached to the supposed "first half" of the process that converts organic detritus into "kerogen."
Which requires the conversion of relatively short-chain molecules into the above long-chain molecules.
But this "first half" rarely gets described in the course of the debate.
Why?
Let me suggest that to the layperson listening to an oil geologist, the "second half," catagenesis, or the "cracking" part of the oil window is more palatable to the mind and oil geolgists know it.
After all, it's a scientific fact that long-chain hydrocarbons can be cracked by heat; and the idea of heat breaking things apart is more agreeable and accessible to "common sense."
After all, people "get it" that heat breaks down chemical bonds.
In contrast, oil geologists "know" that the "first half," diagenesis is a much harder sell, both in terms of supporting scientific evidence and more important, "common sense."
Why?
Because so-called diagenesis goes against "common sense."
People know that "cooking" breaks chemical bonds, it doesn't build them.
Also, in terms of scientific proof, there is NOT ONE EXPERIMENT WITH ANY chemical molecule where low heat in a low pressure environment "builds" chemical bonds.
So, oil geologists know the "first half," of the oil window, diagenesis, doesn't pass the smell test with the average joe on the street.
And the average joe is really their target audience.
Because oil geologists understand people with advanced knowledge of chemistry and physics won't buy "diagenesis."
The key is to play to the people (most of us) that have been conditioned since childhood to believe "fossil" theory.
Because with folks that are conditioned to believe fossil theory (again, almost all of us)all you need is a plausible explanation.
So the next time an oil geologist explains the "oil window," listen closely and see if he fails to explain "diagenesis," and if he doesn't, ask him about diagenesis.
Ask him what the scientific proof is for chemical bonds being "built up" by heat.
See what kind of reaction you get.
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