Margaritifer Basin (Margaritifer Trilogy Book 1) (107 page)

“Uh huh.”

Jeff glanced at his watch.
“Alright, it’s a quarter to three and we’ve been in these suits for over seven
hours. What say we climb inside, get some lunch, and call it a day? We can
resume our sightseeing in the morning.”

“I was hoping you’d say that.”

Wednesday, February
1, 2017

MSD 50865.370 (Sol
115)

In the morning they again suited
up, detached
Amos
from the Genesis trailer, and began exploring the
hills, valleys, mesas, and buttes of the chaos.

“Gabe, why is this so… chaotic?”

“Uh, because it’s a chaos?”

He chuckled. “That’s not what I
mean. The Aram Chaos, for example, has a certain symmetry to it. In some places
it almost looks as though it was laid out with a ruler and cut with a knife.
But this is a mess. There’s no geometry at all to it.”

“Aram is a crater. When the
groundwater release event occurred, the water in Aram had no place to go; it
just ponded. Here the water could flow downstream, so some erosion probably
took place.”

“Aram has an outflow channel.”

“Yes, and the chaos around that channel
is about like this.”

“Not on the south side. There’s
still a large area of symmetrical blocks there.”

“Jeff, it’s Mars. Who knows what
went on here?”

“Well, besides being space
travelers we’re also scientists. Aren’t we supposed to try to figure this stuff
out?”

“I suppose, but I’m a mathematician
and physicist, not a geologist. I had one semester of geology in college, and
Mars was never even mentioned.”

“Right. But, what did this?”

“Subsurface ice, and perhaps liquid
water, instantly evaporated, probably as a result of a giant meteorite strike,
and the overlaying regolith collapsed.”

“Yeah, okay, I understand that
part, but why is it so… chaotic. Why didn’t it collapse uniformly? Why isn’t it
just a big flat sinkhole? This doesn’t look like a riverbed. Water takes the
path of least resistance. The Samara Valles looks like a riverbed. This is
chaos.”

“Probably because this geologic
formation was here before the ice and water. Water flowed down the Loire Valles
from the eastern highlands, and when it reached the volcano it ponded, then
froze. And over who knows how many hundreds of millions of years, atmospheric
dust formed a crust over it. Then when it was vaporized, the surface material
collapsed between the monolithic structures that we’re looking at now.”

“So all this was here before the
initial outflow from the Parana-Loire valley systems?”

“That would be my guess.”

“Okay, so again I ask, what caused
it?”

“I dunno. But most of the bedrock
on Mars that has been sampled so far is basaltic. So, volcanic activity during
planetary formation as the crust cooled? The other possibility is that it’s
ejecta from an impact. The Ladon Valles lowlands could very well be an ancient
impact crater, and over 400 kilometers in diameter, and not that far away. If
it is a crater, the impact almost certainly spewed city-sized rocks hundreds if
not thousands of kilometers. In fact it probably spewed stuff into space.”

“Mind boggling.”

Gabe chuckled. “Yes, well, over the
years that I have known you I have empirically determined that your mind is
easily boggled.”

He laughed. “Ouch. Alright,
wise-ass, why are all the valleys between this jumble of mesas and buttes sand
dunes? Why sand dunes? Why not the remnants of the bedrock that covered the ice
or water when it was evaporated?”

“I don’t know. Maybe because it’s
been sitting here gathering dust for two or three billion years?”

“If that’s so, then the remains
should be somewhere under this sand. Right?”

“Maybe.”

“Well, let’s see.”

“Huh?”

He pulled to a stop in a dune
valley. “Grab a shovel.”

“Jeff, it could be tens or even
hundreds of feet deep.”

“Yeah. Or it may only be a few
inches. Let’s do a little digging and see.”

She sighed. “Oh, alright.”

Three feet down they struck rock.
“That look basaltic to you?”

“Yes.”

“Well, there’s an extinct volcano
about 15 klicks from here.”

“That doesn’t mean anything. This
could be original bedrock that predates the chaos formation event.”

“True. Let’s get some samples.
Maybe the geologists on Earth can make something of it.”

“Okay.”

For two sols they traversed as much
of the chaos as they could, taking numerous samples and photos, and standing in
awe at both the beauty and destruction nature had wrought on the planet.

On the morning of the third day
they packed up and headed west, out of the chaos and down the Loire Valles
toward the confluence of the Loire and Samara. As dusk began to set in, Jeff
rubbed his eyes. “I’m tired.”

“Yeah, me too.”

“I’m gonna tell
Amos
to find
a level spot and we’ll stop for the night.”

“Sounds good to me.”

Jeff stared at the video screen at
the front of the Genesis module. “Wait a minute. What’s that?”

“What’s what?”

“Hang on.” He instructed
Amos
to stop, then zoomed in on a rock formation. “There. See that dark line running
vertically through that rock formation?”

“Yeah.”

He zoomed in further. “Does that
look like a crevice?”

“Hard to say in the shadow, but
could be.”

“Hmmm. If it is, it would be
interesting to see what’s inside one of these rocks.”

“Uh huh. But I really don’t feel
like getting suited up right now.”

“Me neither. This looks like a
pretty level spot. Let’s stop here for the night and go have a look in the
morning.”

Saturday, February 4,
2017

MSD 50868.368 (Sol
118)

“Huh, it is a crevice,” said Jeff.
“And it’s big enough to walk in.”

Gabe stopped at the mouth of the
three-meter wide, thirty-meter high crevice.

“What?”

“It’s dark in there.”

“So switch on your helmet lights.”

“Are you sure there’s nothing
living in there?”

He laughed. “Pretty sure. Come on.”
He switched on his helmet lights and entered the crevice. About ten meters in
Jeff checked his external temperature gauge. “Hey, it’s not only dark in here,
it’s cold. It’s nearly 35ºF out in the valley, but it’s only 17ºF in here. I’ll
bet sunlight never reaches down in here.”

“If it does, it’s only for a couple
minutes a day, and even then only in mid-summer.”

Another twenty meters in and the
crevice began to narrow. “Looks like we won’t be going too much farther. Look
at these walls. They’re much rougher than anything we’ve seen out in the open.”

“Limited erosion.”

“Uh huh. Get some samples from the
walls. Look for any kind of interesting veins. I’m gonna dig a hole in this
sand and see if I can find bedrock. Let’s see if the bedrock and the walls are
the same thing.”

“Okay.”

Jeff started digging. A couple feet
down he hit something hard. “Pay dirt.” He dug out a bit more sand, then got
down on his knees, reached down, and swiped sand off the surface. He stared at
the hard glossy white substance for a moment, then gasped. “Oh my god!”

“What?”

“Come here.”

Gabe got down on her knees beside
him. “What is it?”

“Ice.”

“It can’t be. Not at this
latitude.”

He picked up the rock hammer,
chipped out a chunk, and held it out in the palm of his glove. “Sure looks like
ice.”

“Carbon dioxide?”

“No. Water.”

“How do you know?”

“If it was CO
₂
, at this
temperature it’d be sublimating in my hand. This is water ice.”

“Good god.”

“Yeah. Jackpot.”

“How much do you think there is?”

“No way of knowing. Could be a
couple cubic meters, or a couple cubic miles.”

“Jesus.”

“Go get half a dozen of those
gallon-sized sample bags from
Amos
. I’ll chip out some ice cubes.”

“Roger that.”

A few minutes later Gabe returned.
“Here.”

“Hold one open.” Jeff dropped
chunks of ice in until the bag was full. “Okay, squeeze as much air out as you
can, then double bag it. It’ll probably melt by the time we get back, but at
least we will have captured the essence of it. Then get another bag.”

Gabe sealed the last bag. “Alright,
that’s it”

“Okay, grab the other shovel and
help me bury this.”

“Why?”

“Oh, let’s be environmentally
responsible, and do what we can to see that it doesn’t sublimate. Who knows? We
may want to come back for more.”

After they stowed their samples and
equipment, they returned to the Genesis and got out of their suits. Then Jeff
got on the radio. “Abby, Sue, somebody there?”

A moment later Abby got on the
radio. “Hi, how’s it going? What’s up?”

“You are never going to believe
what we just found?”

“What?”

“Water ice.”

“You’re kidding?!”

“Nope.”

“How much?”

“A couple gallons worth, and
there’s no way of telling how much is still there underground.”

“Oh my god, hydrogen.”

“Yeah.”

“Are you on your way back?”

“No, not yet. We still have a few
more stops to make. Probably be another three days, but we’ll keep in touch.
We’re gonna head on over to the confluence and check that out. We’ll call you
again tomorrow.”

“Roger that.”

Late in the afternoon Jeff pulled
to a stop in a large plain south of two peaks, about 35 kilometers southwest of
the station. “That slope’s too steep. Let’s stop here for the night, then take
Amos
and go down there in the morning. It’s only three or four kilometers.”

Gabe smiled. “Alright.”

Sunday, February 5,
2017

MSD 50869.341 (Sol
119)

Jeff delicately negotiated his way
down the 500-meter slope into the 5-kilometer wide notch carved in the
mountainside at the confluence of the Loire and Samara valles. “Good god, the
west face at its apex has to be the better part of half a mile high. That’s
like Yosemite.”

“Yes, but it’s not. Yosemite Valley
was cut by a glacier, this wasn’t. Yosemite’s faces are sheer and mostly
vertical; this looks more like it was scooped out. This was cut by water, and
whole lot of it.”

“Uh huh. Well, let’s get out and
have a look around. See if we can find anything that was brought down from the
highlands and deposited here. That would pretty much prove the water theory.”

“Okay.”

They climbed out, grabbed a couple
small folding shovels, and began poking around. Jeff dug a hole about a foot
deep, extracted a small sample from the bottom, put it in a plastic bag, and
labeled it. “Hey Gabe, this isn’t dust atop bedrock, and it’s not sand. This
is… for lack of a better word, dirt. And it’s easy to dig in.”

“Uh huh, it’s a flood plain. This
is alluvium, with a thin layer of dust on top.”

“Wish we had
Big Jake
down
here and could dig eight or ten feet into this stuff. See what it’s really made
of.” He heard Gabe gasp softly. “What?”

She walked over to him and held out
her hand. “Look.”

He took the rock and slowly turned
it over in his hand, staring at it in disbelief. “This isn’t iron pyrite.”

“No.”

“It’s gold.”

“Uh huh. A nugget.”

“I’ll be damned. Let’s look around,
see if we can find some more.” After a minute of searching, Jeff found one.
“Found another.”

“So did I.”

He slowly looked around. “Good god,
Gabe, this is a placer deposit; a five square mile placer deposit. Including
what’s buried, there could be hundreds of tons of the stuff in here.”

“Yeah. And that doesn’t include
what’s upstream and further downstream to the west. This is unbelievable. Can
we take some home?”

“Uh, sure, that would be a good
idea. But remember, the sample return MAV has a load limit of 1,500 pounds. If
we take back nothing more than three-quarters of a ton of gold, JPL may be
interested, but a little disappointed.”

“You think?”

“On the other hand, 1,500 pounds of
Martian gold nuggets on eBay might pay for the trip.”

For three hours they walked around
the area picking up nuggets and taking samples. While Gabe hiked over to the
west wall of the notch and took some drill tailing samples, Jeff returned to
Amos
,
pulled out one of their signboards and, with a broad marker, made up a sign.

Gabriel Mine

Trespassers

will be shot.

He attached the sign to a plastic stake, and drove
it into the ground. When Gabe returned he gave her a handful of nuggets and
said, “Go stand by the sign.”

She turned around, looked, and laughed. “You think
we’ll have many trespassers?”

“No, not for a while. But someday they’ll come.”

Jeff took some pictures of her and the sign, then
had
Amos
take pictures of both of them with his MastCam. “Alright, let’s
make sure we’ve got all this stuff tagged and bagged, and head on back. I don’t
know about you, but I’m hungry.”

Tuesday, February 7,
2017

MSD 50871.686 (Sol
121)

The four of them stood silently in the lab, staring
at the pile of plastic-bagged gold nuggets.

Abby picked one up and eyed it carefully. “You’re
sure this is really gold.”

Jeff nodded. “That’s what
Amos
’ laser
spectrometer says, alloyed with about 8% silver and a few trace elements. Roughly
22 carat.”

“And it’s just lying around on the ground?”

“Uh huh.”