kscans

Chapter 204 - Episode 4: Latter Half, Varved Sediments

The layered structure created at the bottom of a lake by the annual cycles of nature, that is, seasonal variation, is called varves, or varved sediments. For example, phytoplankton flourish in a lake from spring to autumn and decrease in the winter. As a result, layers rich in phytoplankton and layers with few of them alternate on the lakebed. These two layers represent one year. The principle is the same as that of tree rings, which are created by the differing growth of trees through the seasons. You could call them the tree rings of a lake.

In my previous life in Japan, there was Lake Suigetsu in Fukui Prefecture, which was arguably the most famous example of varves in the world. Its geography, surrounded by mountains and unaffected by river inflows, produced an unusually long record of annual layers. An astounding seventy thousand years worth. What's more, not a single year was missing. It was worthy of being called, quite literally, a miracle.

It not only provided data on Japan's past climate change, but by analyzing the radioactive isotopes it contained, it even provided a standard for dating across the world.

However, what lies before me now is formed differently, though it is the same in the sense of being a varved sediment. It is what is known as glacial varved clay, a type of annual layer unique to glacial lakes, created by the pattern of glaciers melting more in the summer and very little in the winter.

"So the amount of glacial ice flowing into the lake differs with the season. That's what creates these layers. And the glacier has... ah!"

Maytyl looked up at the top of the cliff, her face suddenly struck with realization. She must be seeing the magic that is invisible to me.

"That's right. The glacier that flows into this lake passes through the magic vent up there. Along with the rock fragments scraped away by the ice. I want you to recall the cultivation of that magic catalyst. The source of the magic catalyst was a culture medium obtained from the soil. In other words, there's a high probability that elements marked by magic exist."

Ordinarily, the glacial clay itself is merely a marker for separating the years. The biological data, such as pollen trapped between the layers, might be what's truly important. But in this investigation, the clay itself is the main event.

When I first came up with the idea of a drilling survey, I was thinking of collecting an ice core. But unlike the snow that accumulates on continents like Antarctica, glaciers flow. On top of that, the samples obtained would mostly contain atmospheric data. This means this glacial varved clay could potentially be a vastly superior sample.

Of course, if there were large scale geographical or climate changes during that time, there's a chance of inconsistencies or gaps in the record. Well, I'm not hoping for anything as extravagant as Lake Suigetsu's seventy thousand years, but I at least want five hundred years of data, less than one hundredth of that. The test drilling just now gave us fifty centimeters, a hundred years worth, so there's reason to be hopeful.

"We can expect denser data spanning a longer period than tree rings."

"A five hundred year record of the magic veins!?"

Crenne, who had approached us at some point, was frozen in place.

"Honestly, the Kingdom barely has any glaciers. What do you think, Crenne. Ricardo is on a completely different level, isn't he."

"B, but then, wouldn't that make it impossible to get recent data?"

Crenne pointed at the glacier. That's right. The data from this year, of course, as well as from the past several decades, has yet to arrive in the lake.

It must be about three hundred meters from the magic vent on the glacier to here. If I remember correctly, the speed of a glacier's movement is a few meters to a few dozen meters per year. Assuming it is five meters, the most recent sixty years of data are still trapped in the ice. We could mark the glacier to figure out its annual movement, but that would take at least a year.

"For that, we'll use tree rings from the trees here. Besides, the most important thing is the record of magic vein activity from four hundred years ago."

"But we don't even know how far back the data goes, do we."

"For that part, I'm thinking of using the building materials from those ruins. By using the tree ring data from the timber used in construction, we can get a record of the several decades before that city was destroyed. We'll look for a place where that data matches up. Of course, a precise comparison is impossible, but if it's a special wavelength like the recent magic vein activity, we can ensure its uniqueness."

"I see... Even crimson is rare, so a wavelength even higher than that... Fufu, this is interesting."

"W, well, that is if everything goes well."

"Well, there's no guarantee. Also, whether or not we can get a good sample is entirely up to you..."

I scratched my head. For example, the glacial lake contains not only rock dust from the magic vent from decades ago, but also leaves and pollen from this year's red trees. In that sense, there is a lot of noise.

But, how should I put it, this whole thing is getting too big. An Imperial Princess is collecting samples while I'm supposed to be guarding a crown prince and an imperial prince. I said there was no guarantee, but if this turns up nothing, my own neck will really be on the line. Still, I can't just see the same wavelength as the crystal and ignore it.

"The cold water made me hesitate a bit, but I'm going to see this through, Crenne."

Maytyl returned to the lake, her face alight with excitement. Crenne nodded silently. Now I just have to count on them. All that's left is the analysis method...

No, I shouldn't count my chickens before they hatch. I'll increase the tree ring samples manually.

Just as I thought that and stood up, a commotion began around the bonfire. A Horse-Dragon knight who had been keeping watch over the surrounding forest galloped toward Dagobard. To my astonishment, Craig was on the back seat of that mount.

"Magic beasts approaching. Everyone, mount up!"

Dagobard's voice rang out. I instinctively looked up at the sky.

"It's from the forest. It's quite large. Crenne, we're stopping work for now. Gather at the Horse-Dragon carriage. Ricardo, you come here too."

Maytyl returned, holding her sorcery staff. I hurried toward the carriage.

"Don't let your guard down. This one's a big one."

Dagobard had skewered something like a magic wolf on the tip of his spear. Its fur was white, like a silver wolf's. Its body was large, too. Even the ones we encountered in front of the ruins were boss-class by Kingdom standards, and this was a step above that. I guess this is what you'd expect from the home turf of magic beasts, so close to the Blood Mountains.

"Dagobard, watch out for wyverns too," Craig's voice echoed. Several wyverns had appeared in the sky above, the magic crystals on their foreheads glowing ominously. Their tanks were full.

A simultaneous attack from land and air. Surely, they're not coordinating, are they.

"Something's strange. The one that just came out is injured."

Crenne, who was supporting the dragon knights with a Spiral Flame, issued a warning. A silver magic wolf had just leapt out of the forest. Its white fur was stained with red blood. The next moment...

Jagiiii!

A cracked, grating cry echoed from deep within the woods. In that instant, the magic wolves bypassed Dagobard and his men, fleeing for their lives. The wolves that raced past the Horse-Dragon carriage didn't even give us a second glance.

In the sky, the wyverns made a sharp turn and disappeared beyond the mountains. A momentary lull in the battle was created.

"What... is this feeling of magic..."

Maytyl looked back at the forest behind her, her shoulders trembling with a start.

At the same time, something burst out from the shadow of a large tree. A huge black object moved through the gaps in the trees' red leaves. It was about the size of a wyvern with its wings spread. And it was vertically long. It clung nimbly to a tree. Black armor covered in thorn-like protuberances covered its body. Yellow, spot-like patterns were visible on its sides. Its abdomen, visible between the trees, looked like a bellows.

The mysterious black magic beast held the bloody leg of a magic wolf in its mouth. Then, two more similar beasts leapt out, cutting us off from Dagobard. Something that looked like a wyvern's wing protruded from one of their mouths.

Looking closely, I could see their jagged mouths were split horizontally.

"That magic beast, its biology is completely different from the others... Maytyl."

A magic beast with a body plan I had never seen before. Both Maytyl and Crenne shook their heads. It was unknown to them as well. But that thing, no matter how you look at it, is the apex predator around here.