Photo Gallery

South of Sarmiento, one comes across a petrified forest known as “Bosque José Ormachea”. It consists of araucaria trunks that are around 70 million years old. Around it stretches the desert, dominated by washed-out, strangely coloured hills. - 1973

South of Sarmiento, one comes across a petrified forest known as “Bosque José Ormachea”. It consists of araucaria trunks that are around 70 million years old. Around it stretches the desert, dominated by washed-out, strangely coloured hills. - Province of Chubut - 1973

South of Sarmiento, one comes across a petrified forest known as “Bosque José Ormachea”. It consists of araucaria trunks that are around 70 million years old. Around it stretches the desert, dominated by washed-out, strangely coloured hills. - Province of Chubut - 1973

South of Sarmiento, one comes across a petrified forest known as “Bosque José Ormachea”. It consists of araucaria trunks that are around 70 million years old. Around it stretches the desert, dominated by washed-out, strangely coloured hills. - Province of Chubut - 1973

Fossil wood is found in various places in the Sahara, especially in the Tidikelt. This is a piece of an old Araucaria. In itself, this once vegetable but now entirely mineral material has nothing to do with prehistory; but it was highly sought after by all the civilisations that followed where it occurred, because it can be worked extraordinarily well. Moreover, it impressively demonstrates that the face of today's Sahara is only a temporary aspect of a landscape that had several times had large forest stands. A few thousand years ago, one could still find large hackberry trees, firs and oaks there ... Much has changed since then. - Algeria - 1966

Fossil wood is found in various places in the Sahara, especially in the Tidikelt. This is a piece of an old Araucaria. In itself, this once vegetable but now entirely mineral material has nothing to do with prehistory; but it was highly sought after by all the civilisations that followed where it occurred, because it can be worked extraordinarily well. Moreover, it impressively demonstrates that the face of today's Sahara is only a temporary aspect of a landscape that had several times had large forest stands. A few thousand years ago, one could still find large hackberry trees, firs and oaks there ... Much has changed since then. - Algeria - 1966

The stone forest of Tin Alkoum, Tassili n' Ajjer (Algeria), is a sight to behold in the Sahara. It is the result of erosion, which is not unusual in itself. Here, however, the factors determining the attack on the minerals are quite peculiar. First of all, there is the abrasion caused by the Saharan storms, which hurl the sand against every obstacle in a manner comparable to a sandblaster. Then there is the difference between the daily temperature maxima and the nightly minima of such magnitude that it causes veritable rock explosions. And finally, although this has practically ceased, the attack by water at a time when the rains fell mainly in the form of thundery and heavy downpours. Witnesses to the violent thunderstorms are the numerous fulgurites or thunderbolts that formed in the sand as a result of lightning strikes by melting it around the impact hole. These hardened tubes were then exposed by erosion. - Algeria - 1969