by ETH Zurich, June 28, 2018 in ScienceDaily
The valley networks of Mars bear a strong resemblance to those found in arid landscapes on Earth. Researchers have been able to demonstrate this using the branching angles of river valley confluences. Based on these observations, they infer that Mars once had a primeval climate in which sporadic heavy precipitation eroded valleys.
by Mark Sagoff, June 29, 2018 in WUWT
In view of the glacial pace of geologic events and the time it takes for things to turn into rock or become encased in it, you might think there would be no hurry to name a new geologic epoch, especially because the current one, the Holocene, started only about 11,500 years ago. You would be wrong. In 2002, Crutzen published an article in Nature magazine, “Geology of Mankind,” which called on geologists “to assign the term ‘Anthropocene’ to the present, in many ways human-dominated, geological epoch, supplementing the Holocene — the warm period of the past 10–12 millennia” and the beginning of which roughly coincided with the advent of human agriculture.The idea of the Anthropocene, which Earth system scientists initiated and advocated, landed like a meteor, setting off a stampede among academics. Nature followed with an editorial that urged that the Anthropocene be added to the geologic timescale. “The first step is to recognize,” Nature editorialized, “that we are in the driver’s seat.”
La géologie, une science plus que passionnante … et diverse