Photograph by Dan Phelps.
Metaconglomerate rock (commercially known as marinace; if anyone knows why, please comment below).
Mr. Phelps writes:
I originally became interested in this rock after reading this blog post. The material was hard to find in small quantities, but I found a company that sells interesting rock slabs to use as cutting boards. If you notice, my slab has handles, which I will probably remove.
The rock is actually a metaconglomerate from Brazil and may represent a metamorphosed Proterozoic glacial tillite.
It is relatively easy to construct an entire series of events that led to the formation of this interesting and beautiful rock. Specimens of this rock might be useful for educators to show basic geologic concepts, including geologic time, to both students and the public.
Note that individual cobbles and pebbles are made of quartzite, gneiss, and what is either a migmatite or a metamorphosed pinkish orthoclase feldspar-rich granite. The greenish black matrix is rich in the mineral chlorite.
I came up with the following steps to form this rock slab. Please comment below or e-mail me at edrioasteroid@msn.com if you think I have missed anything.
1. Deposition of the sediments that make up the precursors of the cobbles/pebbles.
2. Lithification of sedimentary rocks that were the precursors of the cobbles/pebbles. These include sandstone, and shales and siltstones (protoliths of the metamorphic rocks in Step 3).
3. Metamorphism of the sedimentary rocks in Step 2 by heat and pressure, resulting in quartzite and gneiss. Some of the gneiss may have partially melted then crystallized to form a pinkish orthoclase-rich migmatite.
4. Weathering of the metamorphic rocks in Step 3.
5. Erosion of these metamorphic rocks into well-rounded pebbles/cobbles.
6. Deposition of these pebbles/cobbles in a fine-grained mud.
7. Lithification of the sediment from Step 6. This results in a rock type of pebble/cobble sized fragments in a fine-grained mudstone matrix and is called a diamictite. Diamictites often represent lithified glacial till.
8. Metamorphism of the rock formed in Step 7 forming a metaconglomerate. This occurred deep enough underground to change the mudstone matrix into greenish black chlorite.
9. An orogeny (mountain building) event stretched many of the pebbles and cobbles giving the rock a foliation.
10. Pressure solution causes some of the pebbles/cobbles to erode at boundaries where they touch each other.
11. Weathering and erosion bring the metaconglomerate to the surface.
12. Human quarrying followed by cutting and polishing of the slab.
14 Comments
John Harshman · 28 March 2016
I love metaconglomerate, not least because it's a great way to confuse YECs. This is something very similar to your post that I put up on talk.origins several times in hopes that somebody would notice:
A Rock from the Snowy Range
A few years ago I found myself in Laramie, Wyoming, looking for birds, and several friends and I took a short trip to the summit of the nearby Snowy Range. And so I discovered some spectacular geology as interesting as the pine grosbeaks and western pirangas. The Snowy Range (at least what I saw of it) is mostly quartzite and greenschist, the product of continental-scale metamorphism occasioned by some ancient orogeny.
And here and there I saw a few big chunks of metaconglomerate. The rock consisted of white quartz pebbles, an inch or so in averaqe diameter, somewhat flattened, in a darker ground. The pebbles had fuzzy edges, and if the recrystalization had proceeded very much further all I would have seen would have been a purplish gray quartzite.
So I got to thinking. How would a young-earth creationist explain this rock?
I know how I would. First we need a source rock for the pebbles. For such big lumps of quartz that would be a coarse-grained granite. It would form as a pluton intruded miles under the earth, taking millions of years to cool so that the minerals would have time to grow such big crystals. Then erosion and uplift would have had to bring the granite to the surface, where the pebbles would be eroded out of it, and transported by water toward the sea, in the process giving them their rounded form. And then the pebbles would be deposited together with sand in some high-energy process that didn't allow time for sorting of particles by size -- perhaps an alluvial fan built by spring floods. Eventually this fan would be buried deep enough that the mixed sand and pebbles would be cemented together into a conglomerate. Later, that continental-scale metamorphism I mentioned before would cause the conglomerate to recrystallize, atoms migrating to form crystal bonds between sand grain and sand grain, sand grain and pebble. Pressure on the rock made plastic by heat would flatten the originally rounded pebbles too. And so the sedimentary conglomerate becomes a much harder metamorphic metaconglomerate. Finally, the buried metaconglomerate must be uplifted, exposed by erosion, and eroded itself to produce the rock I saw.
So we have a multitude of steps, which I will briefly recap here:
1. Intrusion of magma. 2. Cooling to solid granite. 3. Uplift, erosion of overburden, exposure of granite. 4. Erosion and stream transport of granite pebbles. 5. Deposition of sediment, burying the pebble strata. 6. Formation of conglomerate. 7. More deposition of sediment on top of the conglomerate. 8. Metamorphism of conglomerate. 9. Uplift, erosion of overburden, exposure of metaconglomerate. 10. Erosion of metaconglomerate.
All within a year, or what? Can any YEC enlighten me as to the geological facts?
https://me.yahoo.com/a/JxVN0eQFqtmgoY7wC1cZM44ET_iAanxHQmLgYgX_Zhn8#57cad · 28 March 2016
John Harshman said:
I love metaconglomerate, not least because it's a great way to confuse YECs. This is something very similar to your post that I put up on talk.origins several times in hopes that somebody would notice:
A Rock from the Snowy Range
A few years ago I found myself in Laramie, Wyoming, looking for birds, and several friends and I took a short trip to the summit of the nearby Snowy Range. And so I discovered some spectacular geology as interesting
as the pine grosbeaks and western pirangas. The Snowy Range (at least
what I saw of it) is mostly quartzite and greenschist, the product of
continental-scale metamorphism occasioned by some ancient orogeny.
And here and there I saw a few big chunks of metaconglomerate. The rock
consisted of white quartz pebbles, an inch or so in averaqe diameter,
somewhat flattened, in a darker ground. The pebbles had fuzzy edges, and
if the recrystalization had proceeded very much further all I would have
seen would have been a purplish gray quartzite.
So I got to thinking. How would a young-earth creationist explain this rock?
I know how I would. First we need a source rock for the pebbles. For
such big lumps of quartz that would be a coarse-grained granite. It
would form as a pluton intruded miles under the earth, taking millions
of years to cool so that the minerals would have time to grow such big
crystals. Then erosion and uplift would have had to bring the granite to
the surface, where the pebbles would be eroded out of it, and
transported by water toward the sea, in the process giving them their
rounded form. And then the pebbles would be deposited together with sand
in some high-energy process that didn't allow time for sorting of
particles by size -- perhaps an alluvial fan built by spring floods.
Eventually this fan would be buried deep enough that the mixed sand and
pebbles would be cemented together into a conglomerate. Later, that
continental-scale metamorphism I mentioned before would cause the
conglomerate to recrystallize, atoms migrating to form crystal bonds
between sand grain and sand grain, sand grain and pebble. Pressure on
the rock made plastic by heat would flatten the originally rounded
pebbles too. And so the sedimentary conglomerate becomes a much harder
metamorphic metaconglomerate. Finally, the buried metaconglomerate must
be uplifted, exposed by erosion, and eroded itself to produce the rock I
saw.
So we have a multitude of steps, which I will briefly recap here:
1. Intrusion of magma.
2. Cooling to solid granite.
3. Uplift, erosion of overburden, exposure of granite.
4. Erosion and stream transport of granite pebbles.
5. Deposition of sediment, burying the pebble strata.
6. Formation of conglomerate.
7. More deposition of sediment on top of the conglomerate.
8. Metamorphism of conglomerate.
9. Uplift, erosion of overburden, exposure of metaconglomerate.
10. Erosion of metaconglomerate.
All within a year, or what? Can any YEC enlighten me as to the
geological facts?
But how do you know it wasn't designed?
Satan, God, whoever. Teach the controversy!
Glen Davidson
John Harshman · 28 March 2016
Glen Davidson said:
But how do you know it wasnât designed?
Are you implying that this metaconglomerate was a product of Creation Week, not Fludde Year? I've actually seen a creationist or two make a similar claim. Omphalism solves every problem, no matter what it is!
John Harshman said:
So I got to thinking. How would a young-earth creationist explain this rock?
But how do you know it wasn't designed?
Satan, God, whoever. Teach the controversy!
Glen Davidson
Why think? Why not go straight to the authoritative source: https://answersingenesis.org/geology/basic-geology-disproves-creationism/
As noted here:
" Noahâs Flood is the key to explaining most of the geological record and as such it washes away millions of years."
The Creator can purchase the necessary materials for conglomeration at any local home improvement store. Well, ok, that is not exactly how the author of the article at the link explains it. But he does say:
"Hydraulic cement (available at home building supply stores) can be used underwater to fix cracks in leaky concrete walls. It sets in minutes."
"Noahâs Flood would have produced very energetic waves of water. The rising floodwaters driven by tsunamis (produced by the bursting of the fountains of the great deep: Genesis 7:11) would increasingly assault the continents. Those massive waves would have eroded rock by such processes as abrasion, hydraulic action, and cavitation and then transported the varied-size rubble (mud, sand, pebbles, cobbles and boulders), depositing them elsewhere and producing a wide variety of sedimentary layers that would eventually be hardened into stone (mudstone, limestone, sandstone, conglomerates, and so on) in weeks or months during the Flood or a few years after the Flood depending on the amount of cementing chemicals in the sediments.4 Some of the sediments formed early in the Flood year would be eroded in the recessional stage and deposited again elsewhere, thus providing the slightly older conglomerates within newer ones via successive catastrophic episodes over the course of only a few months or at most a few years, not millions of years."
A bit of fudging, day, week months or at most a few years. "Eventually". But NEVER millions upon millions.
https://me.yahoo.com/a/JxVN0eQFqtmgoY7wC1cZM44ET_iAanxHQmLgYgX_Zhn8#57cad · 28 March 2016
John Harshman said:
So I got to thinking. How would a young-earth creationist explain this rock?
But how do you know it wasn't designed?
Satan, God, whoever. Teach the controversy!
Glen Davidson
Why think? Why not go straight to the authoritative source: https://answersingenesis.org/geology/basic-geology-disproves-creationism/
As noted here:
" Noahâs Flood is the key to explaining most of the geological record and as such it washes away millions of years."
The Creator can purchase the necessary materials for conglomeration at any local home improvement store. Well, ok, that is not exactly how the author of the article at the link explains it. But he does say:
"Hydraulic cement (available at home building supply stores) can be used underwater to fix cracks in leaky concrete walls. It sets in minutes."
"Noahâs Flood would have produced very energetic waves of water. The rising floodwaters driven by tsunamis (produced by the bursting of the fountains of the great deep: Genesis 7:11) would increasingly assault the continents. Those massive waves would have eroded rock by such processes as abrasion, hydraulic action, and cavitation and then transported the varied-size rubble (mud, sand, pebbles, cobbles and boulders), depositing them elsewhere and producing a wide variety of sedimentary layers that would eventually be hardened into stone (mudstone, limestone, sandstone, conglomerates, and so on) in weeks or months during the Flood or a few years after the Flood depending on the amount of cementing chemicals in the sediments.4 Some of the sediments formed early in the Flood year would be eroded in the recessional stage and deposited again elsewhere, thus providing the slightly older conglomerates within newer ones via successive catastrophic episodes over the course of only a few months or at most a few years, not millions of years."
A bit of fudging, day, week months or at most a few years. "Eventually". But NEVER millions upon millions.
Why didn't I think of that? Oh yeah, brain.
I like how they sort of throw in everything (well, not everything, they avoided particularly troublesome issues like metamorphism) all together, writing as if it would all just be fine during an extremely violent flood--including the deposition of very fine sediments (just mention sediments, ignore how long it takes for some particles to settle out from even calm water). Just blather on, ignore the inconvenient details, and yap about how it can all happen quickly, using enough scientific terms that the rubes would think they know what they're talking about. Look at how fast hydraulic cement works. Sheez, like there's any kind of problem.
Sometimes I wish they would just say that God made it all that way, or that Satan planted the evidence. If the Designer can produce all life to work intricately together in massive complexity, even as they're designed to fit into also very complex ecologic arrangements, why couldn't God just design marinace (can be a surname--possible the source? I can't say)? Got to have something for counter surfaces, so why not?
Glen Davidson
Gaythia Weis · 28 March 2016
Complexity builds upon complexity. Now that we know that:
"âNoahâs Flood would have produced very energetic waves of water. The rising floodwaters driven by tsunamis (produced by the bursting of the fountains of the great deep: Genesis 7:11) would increasingly assault the continents."
We ought to run and ask Ken Ham if his model ark is engineered (designed) to weather the oceanic storms. Or perhaps zoom out to the open Atlantic, fast. As Noah's must have.
Dave Luckett · 29 March 2016
Yeah, that's truly weird. The Flood could cause this stone to form, through the action of "very energetic waves" and "tsunamis", which could "assault the continents", but it couldn't sink a wooden ship that couldn't have been seaworthy even when braced and tied with iron and fitted with steam pumps, as experience has shown.
Ah, but for that we invoke miracles. Miracles wherever we want them. Natural processes wherever we want, too (except that they're not really, when you talk about hardening of mud into hard rock over only a thousand years or so). Handwaving to fill the gaps.
Any or all of the above, as required, and if they contradict each other, ehh, who cares?
TomS · 29 March 2016
Dave Luckett said:
Yeah, that's truly weird. The Flood could cause this stone to form, through the action of "very energetic waves" and "tsunamis", which could "assault the continents", but it couldn't sink a wooden ship that couldn't have been seaworthy even when braced and tied with iron and fitted with steam pumps, as experience has shown.
Ah, but for that we invoke miracles. Miracles wherever we want them. Natural processes wherever we want, too (except that they're not really, when you talk about hardening of mud into hard rock over only a thousand years or so). Handwaving to fill the gaps.
And don't forget the creationist version of the second law of thermodynamics, where natural forces can't produce a complex result.
Henry J · 29 March 2016
But but but... ENTROPY!!!1111!!!eleven!!!!!
James · 29 March 2016
Well, one can see by the wheat penny concretion that this conglomerate was made after the flood (ca 1909 to 1958). Perhaps there was some intelligent design to this after all...
David MacMillan · 30 March 2016
They can stack catastrophes.
"CreationWeekDidIt."
"FallDayDidIt."
"FloodDidIt."
"PostFloodErosionDidIt."
"IceAgeDidIt."
"IceAgeMeltingDidIt."
With a few stacked catastrophes they can (pretend to) explain anything.
DS · 31 March 2016
You forgot the rupture. These are the end times, it's going to happen any day now!
Henry J · 31 March 2016
What, you mean the end times won't wait a billion years or so, for the sun to have grown ten percent bigger in surface area than it is now?
(I got that tidbit from Wiki article on Yellow Dwarf life cycles.)
Marilyn · 1 April 2016
David MacMillan said:
They can stack catastrophes.
"CreationWeekDidIt."
"FallDayDidIt."
"FloodDidIt."
"PostFloodErosionDidIt."
"IceAgeDidIt."
"IceAgeMeltingDidIt."
With a few stacked catastrophes they can (pretend to) explain anything.
It's been through all that and it's still stuck together, I'd call that a miracle.
14 Comments
John Harshman · 28 March 2016
I love metaconglomerate, not least because it's a great way to confuse YECs. This is something very similar to your post that I put up on talk.origins several times in hopes that somebody would notice:
A Rock from the Snowy Range
A few years ago I found myself in Laramie, Wyoming, looking for birds, and several friends and I took a short trip to the summit of the nearby Snowy Range. And so I discovered some spectacular geology as interesting
as the pine grosbeaks and western pirangas. The Snowy Range (at least
what I saw of it) is mostly quartzite and greenschist, the product of
continental-scale metamorphism occasioned by some ancient orogeny.
And here and there I saw a few big chunks of metaconglomerate. The rock
consisted of white quartz pebbles, an inch or so in averaqe diameter,
somewhat flattened, in a darker ground. The pebbles had fuzzy edges, and
if the recrystalization had proceeded very much further all I would have
seen would have been a purplish gray quartzite.
So I got to thinking. How would a young-earth creationist explain this rock?
I know how I would. First we need a source rock for the pebbles. For
such big lumps of quartz that would be a coarse-grained granite. It
would form as a pluton intruded miles under the earth, taking millions
of years to cool so that the minerals would have time to grow such big
crystals. Then erosion and uplift would have had to bring the granite to
the surface, where the pebbles would be eroded out of it, and
transported by water toward the sea, in the process giving them their
rounded form. And then the pebbles would be deposited together with sand
in some high-energy process that didn't allow time for sorting of
particles by size -- perhaps an alluvial fan built by spring floods.
Eventually this fan would be buried deep enough that the mixed sand and
pebbles would be cemented together into a conglomerate. Later, that
continental-scale metamorphism I mentioned before would cause the
conglomerate to recrystallize, atoms migrating to form crystal bonds
between sand grain and sand grain, sand grain and pebble. Pressure on
the rock made plastic by heat would flatten the originally rounded
pebbles too. And so the sedimentary conglomerate becomes a much harder
metamorphic metaconglomerate. Finally, the buried metaconglomerate must
be uplifted, exposed by erosion, and eroded itself to produce the rock I
saw.
So we have a multitude of steps, which I will briefly recap here:
1. Intrusion of magma.
2. Cooling to solid granite.
3. Uplift, erosion of overburden, exposure of granite.
4. Erosion and stream transport of granite pebbles.
5. Deposition of sediment, burying the pebble strata.
6. Formation of conglomerate.
7. More deposition of sediment on top of the conglomerate.
8. Metamorphism of conglomerate.
9. Uplift, erosion of overburden, exposure of metaconglomerate.
10. Erosion of metaconglomerate.
All within a year, or what? Can any YEC enlighten me as to the
geological facts?
https://me.yahoo.com/a/JxVN0eQFqtmgoY7wC1cZM44ET_iAanxHQmLgYgX_Zhn8#57cad · 28 March 2016
John Harshman · 28 March 2016
Gaythia Weis · 28 March 2016
https://me.yahoo.com/a/JxVN0eQFqtmgoY7wC1cZM44ET_iAanxHQmLgYgX_Zhn8#57cad · 28 March 2016
Gaythia Weis · 28 March 2016
Complexity builds upon complexity. Now that we know that:
"âNoahâs Flood would have produced very energetic waves of water. The rising floodwaters driven by tsunamis (produced by the bursting of the fountains of the great deep: Genesis 7:11) would increasingly assault the continents."
We ought to run and ask Ken Ham if his model ark is engineered (designed) to weather the oceanic storms. Or perhaps zoom out to the open Atlantic, fast. As Noah's must have.
Dave Luckett · 29 March 2016
Yeah, that's truly weird. The Flood could cause this stone to form, through the action of "very energetic waves" and "tsunamis", which could "assault the continents", but it couldn't sink a wooden ship that couldn't have been seaworthy even when braced and tied with iron and fitted with steam pumps, as experience has shown.
Ah, but for that we invoke miracles. Miracles wherever we want them. Natural processes wherever we want, too (except that they're not really, when you talk about hardening of mud into hard rock over only a thousand years or so). Handwaving to fill the gaps.
Any or all of the above, as required, and if they contradict each other, ehh, who cares?
TomS · 29 March 2016
Henry J · 29 March 2016
But but but... ENTROPY!!!1111!!!eleven!!!!!
James · 29 March 2016
Well, one can see by the wheat penny concretion that this conglomerate was made after the flood (ca 1909 to 1958). Perhaps there was some intelligent design to this after all...
David MacMillan · 30 March 2016
They can stack catastrophes.
"CreationWeekDidIt."
"FallDayDidIt."
"FloodDidIt."
"PostFloodErosionDidIt."
"IceAgeDidIt."
"IceAgeMeltingDidIt."
With a few stacked catastrophes they can (pretend to) explain anything.
DS · 31 March 2016
You forgot the rupture. These are the end times, it's going to happen any day now!
Henry J · 31 March 2016
What, you mean the end times won't wait a billion years or so, for the sun to have grown ten percent bigger in surface area than it is now?
(I got that tidbit from Wiki article on Yellow Dwarf life cycles.)
Marilyn · 1 April 2016