Bisti Badlands

27 Mar 2016

  ... the Bisti Badlands are located in New Mexico. At www.smithsonianmagazine.com/travel/these-massive-rock-formations-look-ju... ... we learn the Badlands have pillars of eroded sandstone rock and weird formations that look as so fragile that a blustery wind might blow them over. The giant cracked eggs are on the ground - but they are also entirely geological in origin. They are said to go back 73 million years ago, within the Late Cretaceous period (the last bit of the dinosaur age). At this time New Mexico was submerged benath the Western Interior Seaway and when the waters receded they left behind a strata of sandstone, mudstone, shale and various other sedimentary rocks with a watery origin. The interior seaway is interesting - and so is the asteroid strike that closed the Cretaceous a few million years later. Was the seaway contemporary with a Cretaceous period that lasted millions of years or was the seaway a geological phenomenon created by the end of Cretaceous K/T boundary event? In other words, a giant tsunami wave that struck out from the Gulf - not too far from the impact site on the other side of the Caribbean. It depends on how you look at the geological record I suppose. Is it a record of continuous laying down of strata one on top of the other, somewhat like a layer cake, or is the geological record simply the catastrophic incidents that have punctuated the past? If so the Cretaceous period may have been much shorter than geochronology allows - and the Jurassic possibly even more extensive than geochronology allows.

   When the waters receded and the sediments were left high and dry the process of erosion began, and braided streams of rivers are blamed for many of the features, a quite telling explanation as a giant tsunami wave that receded gradually could have produced a similar effect. Later, when the climate dried out wind erosion contributed to the decimation of the sandstone and weathering of the mudstone sedimentary layers. It was in particular the erosion of the mudstone that left behind the strange egg formations. The colours in the eggs are due to mineral deposits in the braided streams of water.

The Bisti Badlands are a 3 hour drive from Alburquerque.