ADVENTURES WITH ROCKS (TM): Deserts, Plankton and Bighorn Sheep

From the top of the next hill we had a gorgeous view of the desert, spreading out in all directions away from us. The tiny town of Beatty was only 6 miles away, nestled in a little valley along the Amargosa River, but we couldn’t see it from our vantage point. The only way we could tell there was a town there is because of the huge “B” drawn in rocks on a peak above the town. People like to draw things with rocks out in the desert, it seems. There’s a big “Q” drawn in rocks on a mountain above Quartzsite, too. “Q” Mountain they call it…real creative.

Anyway, we could see Beatty’s “B” from where we were standing, so that was our directional reference point. Other than that, we were in the middle of nowhere. We had left Mud Mound and followed a 4-wheel drive road through some steep desert terrain until we got to a gravel road that appeared out of nowhere and headed up to the top of the hill we were now standing on. It was actually more like a small mountain, with steep gorges on one side. And it was from there that we were looking out at the immense desert landscape. It was beautiful, awe-inspiring, and a little intimidating. I have been exploring deserts since 2007, and I am still captivated by them. They are studies in contrasts: intense and subtle, harsh and delicate, colorful and drab, enticing and foreboding, comfortable, yet intimidating. Here, with a 360 degree view, I was experiencing all of those things at once.

“Hey,” Al said. “What are you doin’?” “Looking at the desert”, I said. “It’s so beautiful from up here.” He had bounded out of the car and was searching for fossils already, and now he came over to look at the view. We spent a few minutes taking pictures and then…we saw them. Fossils. And the more we looked, the more we saw. They were everywhere at the top of this hill. “Jackpot!” we giggled- like little kids. And these were not like the Mud Mound fossils at all. These were little squiggly worm-looking pale lines in flat chunks of shale called graptolites- fossilized plankton colonies-again from the Ordovician era.

Graptolites are found in shales made of sediment deposited in relatively deep water with poor bottom circulation and very little oxygen. Because of the lack of oxygen, there would have been no scavengers to eat the plankton as it settled on the bottom, where it would become entombed as layers of sediments accumulated. Graptolites are typically preserved as a light grey clay film on the surface of the shale- almost resembling a hieroglyphic or a pictograph. In fact, when I saw the first one, I thought it was a pottery shard with a pale design on it. But then we realized that we were looking at fossils scattered on the ground all over the top of this hill.

There were bunches of them on the surface, but even more were underneath and in pockets of other rocks. “Wow!“ “Look at this!” Al yelled from across the hill. I grabbed my backpack – the old one I use to put rocks in- and ran over to him. He was sitting on the side of the hill with piles of plankton fossils all around him. Shale has lots of cleavages, so it would peel apart in layers exposing more fossils inside. “They’re everywhere over here!” and he pointed to a rock he’d been peeling layers off of. We started loading up the backpack. “These are amazing!” He picked up a little hunk of shale, and said, “Watch.” He pushed on a crack in the edge and a slice popped off. Inside were a dozen or so of those squiggly, wormlike, hieroglyphic-looking pale imprints on the darker rock. He popped off another layer and there were more in that one- on both sides. The whole chunk was full of layers of them. “How cool is that!” We giggled again.

We spent the next couple hours gathering up graptolite fossils. The shale was different colors depending on where you found it. Most of it was gray in some shade or other, but there were reds and purples and browns, too. We tried to collect as many of the different colors as we could. Just the sheer fact that the shale was in so many different colors was amazing to me. I’d only ever seen gray shale up to that point.

The backpack had reached capacity a while ago. We emptied it in the back of the Samurai and now it was almost full again. The sun was starting to get low. Besides, there were still some old mines and cabins to see on the way back. It was time to go. We peeled ourselves away from the side of the hill. Leaving is always hard. There is always one more to pick up. So we walked the perimeter very slowly one more time, circling back to the car. We found more as we went, and now the backpack was full. Only two choices were left. Empty it and stay long enough to fill it a third time, or call it a day and head back. The time and the weather made our choice easier. “Come on.” Al said. “We found alot. Let’s go explore some of those mines before it gets dark.” I took one last long look and reached down to pick up just one more. Rocks are so addictive.

Some of the Graptolites we collected.

“Besides, we might see some of the burros or bighorn sheep if we head out now,” he said. A spring near here was a known watering hole for herds of bighorn sheep. That did it. Animals trump rocks. For me, anyway. They’re harder to find, so the reward is even sweeter. We jumped into the car and headed back down the hill. And we were off to the spring with a load of fossilized plankton and algae bumping around behind us. We were tired and it was starting to get cold. But the spring was only a mile or so from where we were, and the chance to see Bighorns was calling, so we headed toward the next peak on the map. Our day’s Adventure wasn’t over yet!