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Back from Texas (again) - The petrified wood of Texas
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© Pictures : MJX, except otherwise specified.


Marc Jauniaux

After a tiring week in the Deer Park's and Chocolate Bayou's factories ( 50 km in the Southeast of Houston), we took advantage of sunny Saturday of back season (hardly 85°F and 95 % of humidity) to make a field trips in the Bryan's region.

The most interesting sites are in fact at College Station, not far from Texas A and M (Agriculture and Mechanic), the University of the « Aggies». It is also the homeland of the Bushs, Father and Son….

This region is particularly known for its petrified wood.

Obviously, they are not worth the magnificent colored logs of Araucarioxylon arizonicum of Arizona, that it is for example strictly forbidden to take home in the Petrified Forest National Park :

Araucarioxylon arizonicum
Araucarioxylon arizonicum Coll MJX

Petrified Forest Photos Petrified Forest , the story behind the scenery , ©PFMA

or the belgian petrified woods of Hoegaarden.

glyptostrobus
Glyptostrobus sp - Thanetian (Upper Landenian) - Hoegaarden - (distance between lines : 5cm) - coll MJX

But the whole pleasure is to find them in the heart of the rivers and to bring them back home...

The age of formation of the petrified wood of Arizona dates from the end of the Trias, Chinle formation.

Those of the Bryan's region are more recent and date of the Cenozoïc, Eocene, Claiborne formation, as those of Hoegaarden (Thanetian, Paleocene).

In fact, all the creeks or ravines dug by the rainy waters are covered with almost perfectly preserved petrified wood.

Although fossilisation was studied for many years, it is not still well understood.

We have in this case a permineralisation. The trees of origin were submerged doubtless quickly in highly mineralised waters, that protected them from rotting and so from a complete disappearance. Only the leaves and small branches disappeared. The rest of the organic matter was slowly replaced by silica (chalcedony or agate) while preserving not only the outside form but also all the internal details, as the veins, the knots, the worm holes, the cells of the wood, so that, with a microscope, one can « easily » determine the family and the species. From the material of origin, there are only some traces. The different colorings are due to the presence of traces of other elements, like iron, carbon, manganese, …

In the region, one can find palm trees (Palmoxylon), but in small fragments of centimetric size. The beautiful slices come from the Polk's county, more in the East, from the lake Somville, more on the West, and from Louisiane.

Palmoxylon
Palmoxylon Polk County Texas Coll MJX

On trouve également des petits morceaux de « snakewood » (Mennegoxylon), dont la tranche polie ressemble à une peau de serpent.

Toutes les zones en construction sont intéressantes à parcourir après une forte pluieCe qui n'est pas argile boueux, c'est du bois pétrifié !!

Dans la White Creek et dans la Turkey Creek, que nous avons parcourues sur quelques kilomètres, on ne trouve que des troncs indéterminés parfois agatisés en gris ou noir.

petrified wood

What retains the collector, it is the weight  ! Do not forget that the whole vegetal material was replaced by quartz of a density of 2.6 …

The following day, on Sunday, a thunderstorm, that lasted the whole night, transformed the creek into a howling torrent of muddy water , totally inaccessible at the risk of drowning …

The trunks left on the spot were marked. I hope to be going to look for them during a next visit …

In spite of the very severe controls, my suitcase of 100 lbs was loaded without problem in the holds of Air France and arrived without damage in Brussels … I am looking for a container to repatriate the other logs…  

Other pictures of petrified woods...


Small petrified wooden sample from Oklahoma in a garden of Houston


Johnson's garden at Indian Springs


petrified wooden house in Bryan


extraction of a petrified log from Turkey Creek


specimen of 400 lbs

I thank the Houston Gem and Mineral Society ( HGMS  : http://www.hgms.org ) to have well wanted to organize this field trip and to have allowed me to participate as a former member.

Thank you also to Carine and Abel for their precious help for the transport (we have extracted about 600 lbs of wood from the creek ), the appropiate clothing , the cleaning and the drying (there were holes of 3 ft in the bottom of the creek, in which we fell naturally …), the jambalaya of crawfish after the effort, …


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