We departed the alpaca ranch on a chilly morning. Our hosts had suggested where we could get the best deal on gasoline – not that there was much choice in the thinly populated border area near the New Mexico – Arizona state line. The grocery store in Quemado also sells fuel.
Because of the cold Bill was wearing a hat; a black, knitted affair with “New Zealand” embroidered on it. “You've been to New Zealand?” a young man asked. “I live there.” Turned out the questioner was another Kiwi.
The Petrified Forest is a national park with fossilised trees. Before we got there, that was all we knew. In fact there are vast numbers of fossilised trees and parts of trees, and quite a bit more besides. To begin our education we went directly to the Visitor Center. A white board announced a Ranger-led wild flower walk, starting in half an hour. We accepted a free map and set off for the wild flowers.
Most of the park is dry and apparently without vegetation, but if you look closely …
Tiny but very pretty flowers
A desert Evening Primrose.
The strap-like leaves belong to another plant
Another tiny but pretty little flower.
Note the hairy leaves designed to trap dew and protect the plant too.
Another Evening Primrose
This plant has slightly succulent leaves, once again with tiny hairs
to protect it from the heat and giving it a greyish colour.
No name again but close-up the flowers are pretty.
Same as above.
A Vicious Vetch! This plant is covered with tiny spines
that transfer to your fingers if you touch it.
Daisies of an unknown variety
Pretty Pink
The ranger was a highly qualified academic (her planned retirement project is to get a PhD), but Eve's knowledge was ample for discussion of the plants we were seeing. And her camera was busy. However, Bill's camera is better for close-ups so the above are from both photographers.
Some time on the first afternoon we came across these layered, multicoloured rocks. At the time these were quite a novelty. We've since learned that the USA has a great variety of layered, multicoloured rocks; some of them even more spectacular.
Around the visitor center and scattered around the park are, of course, fossilised trees. Almost all of them are sliced neatly into short lengths. Bill developed a hypothesis that the ancient Arizona forests were inhabited by the terrible Chainosaurus Rex that cut through fallen tree trunks.
The key information board. To save you hunting round for a magnifying glass we have transcribed it for you:
What happened to the trees?
Approximately 218 million years ago, during the Triassic Period, this spot was the edge of a river channel. Fallen trees crisscrossed the channel and adjacent floodplain. Periodic flooding buried some of those logs beneath layers of silt. Through time, silica enriched groundwater percolated through the logs, replacing the organic molecules in the wood, and creating a replica in quartz. Continuing erosion brings the quartz logs back to the surface.
How long does it take a tree to petrify?
It depends. Environmental conditions, like burial rate and amount of silica in groundwater, affect speed of petrification. The initial stages may take only decades, but it takes millions of years for the silica's molecular changes to result in colourful crystalline quartz. The logs buried here during the Triassic Period had become solid crystalline quartz by the time T. Rex walked the land some 135 million years later.
What do the colours mean?
Contamination. Mineral impurities within the quartz give the wood its various colours.
Iron oxides: Red, yellow, orange and purple.
Manganese oxides: Black and grey.
Pure quartz: White.
Who cut the wood?
No one. Settling of a heavy quartz log causes cracks and eventually breaks. Because it is the shortest distance for the crack to grow, the logs breaks perpendicular to their length, like a length of brittle chalk. The repeating perpendicular breaks make the logs look like they were sawed or cut.
So the Chainosaurus notion is not supported by the scientists, but we think their theory is much less exciting. ;-)
We got into conversation with another couple in an RV. They had found campsites outside the South Entrance to the park. On the East side of the road one could park for nothing, but all you got was level gravel to park on. To the West the levy was $10, but power was provided. Recent nights had been cold and our furnace did not run on the on-board 12-volt system. So we elected to pay.
Our new friends invited us to join them for the evening. We played a board game. It was something they had invented, based on Ludo. The board was quite thick and the players use pegs rather than counters. It was a surprisingly appealing game.
It was another cold night and we were grateful for a working furnace.
The first afternoon in the park had allowed us to get our bearings, as well as be shown the wild flowers. The park is quite large and fossilised logs are found over a wide area. They are found outside the national park as well, so souvenir logs and fragments are easily obtained.
Many of the fossils are substantial lengths from a single tree:
Others are smaller portions:
How did these get so widely scattered?
A stump.
Knots still clearly visible.
It looks as though you can count the growth rings.
And on this one.
As with 'ordinary' rocks, lichens sometimes colonise.
A close up.
The fossil trees are revealed as the softer rock around them is eroded. This one became a bridge when the rock below it was washed away. The concrete support was added before the fossil split.
Occasionally cavities in the petrified wood grow crystals:
A panorama of the terrain.
There's more to the park than wildflowers and fossilised trees.
A hoodoo forming in the layered rocks.
Petroglyphs
.More petroglyphs.
The remains of a Puebloan settlement. The lack of doorways is because the buildings were entered through the roof.
Like many civilisations, the Puebloans studied the skies. This board explains how a split rock was aligned to identify the solstice.
There didn't seem to be much wildlife, but there were some birds out in the open.
An unidentified little bird. Probably a kind of sparrow.
Few birds are found in more diverse habitats and have more self-confidence than ravens.
Historic Route 66, made famous by the song, passes through the North of the park. We had travelled a part of it earlier between Moriarty and Albuqurque. Someone decided that it needed a marker.
A 1932 Studebaker is part of the Route 66 Monument.
North of Route 66, at the edge of the park, the topography was quite different.
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