Soupy: Our favorite fruit bat!
What's new with Soupy!
Soupy learns about minerals and rocks :
Soupy asks, “Patty, what are you going to do with this rock?”
“We are going to take a look at it with a microscope to see what minerals are in it.”
“The microscope is that thing Ann was looking at the other day, right? So what’s a mineral?”
“Well, here’s a definition that you can find in a book. A mineral is a naturally occurring inorganic solid with a specific chemical composition (although sometimes the actual elements that make it up can vary a little bit) and a particular internal structure.”
“Soupy…!” Patty shouts.
“Soupy, Wake Up!!”
“Hmmmm, what part did I miss?” mumbles Soupy.
“OK, look at it this way, minerals help fruit trees to grow. They are in the soil the trees and bushes grow in and provide the plants with nutrients (food) that they need along with sunlight to grow big juicy fruit and nice succulent flowers with lots of nectar for you to eat."
“Now you’re talking!” Says Soupy with enthusiasm, “ So how do the minerals get into the dirt?”
“You live on Guam right?”
Soupy rolls his beady little eyes, “Like, duhhh!”
“Well, part of the island is volcanic and part is uplifted ancient reefs. The volcanic part is made up of lava rocks that erupted long ago and those lava rocks are actually made up of tiny mineral grains and some volcanic glass.”
“Part of the island is VOLCANIC? You mean it could blow up??!!” shrieks Soupy.
“Calm down! It’s part of an extinct volcano. It erupted millions of years ago and it’s not going to do it again.”
“How do you KNOW that?” Soupy interrupts, panic stricken.
“The volcanic centers of the Mariana region moved away from Guam a long time ago. There is a volcano on the seafloor (Tracey Seamount) not too far west of Guam, but there aren’t any active volcanoes on Guam itself.”
Soupy settles his leathery wings around himself for comfort and asks again, “So how DO the minerals get into the dirt?”
“They form in the first place when the magma (molten rock) beneath the volcano starts too cool enough for them to begin growing. Each mineral starts to grow at a particular temperature as the magma cools. They start out as tiny crystals too small to see without a microscope. The longer it takes the magma to cool the bigger the crystals grow. When the magma erupts as lava and runs down the sides of the volcano, the lava cools much faster and whatever crystals of minerals have started to grow in the lava tend to get stuck in the lava, sort of “frozen in,” and surrounded by uncrystallized lava that cools quickly. Magma that cools really fast doesn’t make mineral crystals, it makes volcanic glass.”
“OK, but how do the minerals get into the dirt??”
“Once the lava has erupted it is exposed to sun, wind, and rain and the lava “erodes.” Erosion in warm places like Guam mostly is caused by rain. Rain wears the rock away, especially if it happens to be loose volcanic cinders or ash. Rain water also combines with the minerals and volcanic glass in the lava to change them into other minerals. Basically this is how dirt is made.”
Soupy has a stray thought, “What happens if there isn’t an eruption? I mean, what if the magma stays down there under the volcano? Do we ever get the minerals in that magma for dirt?”
“When you fold yourself up in your wings they are sort of like a blanket right? They keep you warm don’t they?”
“Well, they are pretty thin, but they do cut down on the breeze, so I guess they keep me warmer than if I didn’t have them.” says Soupy.
“If magma stays underground it is better insulated, so it stays warm longer than if it erupts at the surface. All the rock above it acts like a blanket and it takes a longer time to cool. The longer a mineral has to grow in the magma, the bigger it gets. Sometimes the minerals grow large enough to bump into one another at their edges. They sort of crowd into one another and so eventually they sort of grow together like pieces of a jig-saw puzzle.”
“So,” says Soupy, his eyes bright with sudden understanding, “rocks are made up of mineral crystals and if they are lava rocks the crystals are stuck in volcanic glass and if they are magma rocks they are stuck together just because they sort of lock together as they grow?“
“You’re pretty smart, for a bat!” says Patty, “but we don’t call the rocks that form when magma cools and solidifies underground “magma rocks.” We use a different name. We call them “plutonic rocks. They are named after the ancient Greek god of the underworld, Pluto.”
“ Yeah, yeah,” sighs Soupy, obviously not interested in the fine points, “but do they ever form dirt?”
“Yes,” says Patty, “they can, but all the rocks overlying them have to be eroded and worn away before the plutonic rocks can get exposed to the sun, and wind, and rain. If they do, then yes, plutonic rocks can be eroded and form dirt too.”
“Hey!” Soupy interrupts again, “Wait a minute, if Guam is millions of years old and it has been wearing away, “eroding” you call it? …”
“Yes, eroding.” Patty assures him.
“..all this time, then,” Soupy smugly continues, “it seems to me it should have a lot more dirt.”
Patty asks Soupy, “Have you noticed that after a heavy rain storm or a typhoon the ocean water around the island looks brown and murky?” Soupy nods, “That is dirt that has been washed off the island and into the sea. That dirt, we call it sediment, settles down to the seafloor and over many millions of years it builds up into thick layers. There are other things that settle to the sea floor too. There is wind-blown dust from China, ash from volcanic eruptions in the Mariana islands, and the shells of one-celled animals that live in the ocean and fall to the seafloor after the animals die. If the layers of this stuff get thick enough, the bottom of the pile starts to get squashed. Eventually the stuff buried at the bottom of the pile gets pressed together so hard that all the water between the grains of sand, dust, ash, and shells is squeezed out and the sediment actually becomes rock-hard. We call this new sort of rock a sedimentary rock.”
“ANOTHER kind of rock?” Asks Soupy, suddenly frantic to get it all straight. “You’ve got volcanic rocks, plutonic rocks, and now sedimentary rocks! Just how many kinds of rocks are there?”
“Just one more.” Patty says, though wondering if Soupy’s tiny head can absorb all this.
“OK, I’m listening.” says Soupy, his patience just about running out.
Patty explains, “If any of the three other sorts of rocks get buried deep enough, or if a magma body oozes its way through another type of rock, the minerals in the original rock can change.”
Soupy shakes his head and a faint rattling sound fills the Main Lab “They change?“ He looks hopelessly confused. ”You mean into dirt?”
“No,” Patty coughs, trying to hide a snicker, “into other minerals.”
“One mineral changes into another mineral? How can it do that? I don’t believe it!” says Soupy and he eyes Patty, doubting that she is telling the truth.
“What it takes” explains Patty, “is enough pressure to squeeze the mineral structure so that it changes shape, or enough fluid flowing through the rock to let some of the atoms in a mineral change places with other atoms in the fluid going through the rock, or enough heat energy (like from a nearby magma) to rearrange the atoms in a mineral. Basically, the crystals of the minerals in the rocks change shape or composition, they recrystallize. This sort of thing takes place slowly, but with enough time a huge area of rock can be completely changed into a different sort of rock.”
“Let me get this straight,” says Soupy doubtfully. “You are saying there are lava rocks, plutonic rocks, sedimentary rocks, and “change” rocks?"
“Oh, dear,” sighs Patty, “no, we don’t call them “change” rocks. We have another name for them.”
“You guys just want to make this hard don’t you?” says Soupy getting angry. “Why can’t you just call them “change” rocks?”
“Well,” frowns Patty, beginning to wonder herself why it has to be difficult in the first place, “Actually we do, in a way. We call them “metamorphic” rocks, using the word that means to change (metamorphose). Like a silk worm metamorphoses into a moth or a caterpillar metamorphoses into a butterfly, a metamorphic rock is one that has changed from one type of rock into another because the minerals that make it up have changed.”
“In fact,” says Patty wondering if she is taking things a bit too far, “rocks that get buried deep enough can actually get hot enough to start melting and turn back into magma.”
“Ok, Ok, just let me ask you this,” cries Soupy, “do metamorphic rocks make dirt too?”
“Yes, sure they do. All that has to happen is that all the stuff on top of them must erode away so they can be exposed to the sun, wind, and rain. Then they can turn into dirt.”
Soupy looks at Patty for a loooooong minute. He nods his head up and down very, very slowly, “So all types of rocks can make dirt?”
“Yes!” says Patty wondering what is going on in his fuzzy skull.
“Now let me get this straight,” says Soupy rustling his wings and settling himself down to think. “Magma deep underground starts growing crystals of minerals that erupt with the magma to form lava rock. Sometimes minerals grow big and form plutonic rock if the magma does not erupt. If these rocks get up to the surface either by erupting or if the stuff over them erodes away and they get uncovered then they erode too. All this eroded stuff makes dirt that can get washed into the ocean and settles out as sediment that gets squashed into sedimentary rock and if it gets buried deep enough it can change into metamorphic rocks or maybe even melt and change into magma again. Then the whole thing starts ALL OVER AGAIN???” Says Soupy as he goes teetering around on the table in the Main Lab with his wings flapping to keep him upright and his eyes spinning.