On Hawaii, lava fields fall into two camps – pahoehoe and a’a. This week’s Imageo on Mondays puts the two into perspective… Pahoehoe fields are created when the lava is well insulated at the surface. The cooled rock on top prevents a lot of heat escaping and lets the lava flow beneath a tough skin of basalt. This skin is pulled and distorted by the moving lava, creating ripples and wrinkles that r ...[Read More]
Imaggeo on Mondays: A rolling stone gathers no moss
Philippe Leloup brings us this week’s Imaggeo on Mondays, with tales from a mountain trail that show a geologist can never resist a good rock! This image is that of a polished slab of a rock composed of interlayered marbles and amphibolites. The sample was once part of a small dry-stone wall bordering an outdoor kitchen along a trail along the Ailao Mountain Range in China (or Ailao Shan in Chines ...[Read More]
Imaggeo on Mondays: Rockscape
A geologist out in the field is often the one doing the mapping, but sometimes you might just find a map while you’re out there. Martin Reiser shares how he stumbled one such stunning feature… The picture shows colourful marly layers in a Triassic limestone of northwest Albania (Lezhe region). The marly layers have developed intense reddish and greenish colours due to exposure to reduction and oxi ...[Read More]
Imaggeo on Mondays: Winter waterfalls reveal their secrets
Cyril Mayaud is kicking of this week’s Imaggeo on Mondays with an insight into what waterfalls in winter can tell us about their local hydrology… The picture below shows the lower Peričnik waterfall during winter season. This cascade system is composed of two successive waterfalls that stretch some 16 metres (upper fall) and 52 metres (lower fall) high and is one of the most beautiful natur ...[Read More]