Several processes have been proposed as triggering mechanisms for the large sector collapses that affect most volcanoes, and which may occur several times in volcano's lifetime. Here we present discuss case of Tutupaca volcano, located southern Peru part Central Volcanic Zone Andes. is composed an old, hydrothermally altered highly eroded Basal edifice, well younger twin peaks northern complex ...

The basalts within Oceanus Procellarum have been named the Oceanus Procellarum Group and subdivided into four major geologic units on the basis of morphology, spectral reflectance, and other remote sensing information in order to develop a framework of regional stratigraphy for the largest lunar mare. The oldest mare basalt unit identified, the Repsold Formation (blue color, low albedo, high cr...

The lunar regolith records both the geological history and processes of the Moon and also that of particles from the Sun and galaxy. Such a record extends back to the age of the rock unit upon which the regolith is developed, but complex impact gardening and processing makes this record difficult to recover and interpret. Ancient rock units, such as lava flows, begin to have regolith developed ...