Earth rocks

The Oldest Earth and Moon Rocks

Introduction: We describe a project that could greatly alter our understanding of the environment on Earth at the time in which life originated. The approach is to systematically search for terrestrial rock and mineral samples that should be present on the lunar surface due to impacts, and in selected terrestrial localities. Project activities include studies of terrestrial materials, developme...

The Composition of Earth: Rocks and Minerals

Microorganisms in desert rocks: the edge of life on Earth.

This article reviews current knowledge on microbial communities inhabiting endolithic habitats in the arid and hyper-arid regions of our planet. In these extremely dry environments, the most common survival strategy is to colonize the interiors of rocks. This habitat provides thermal buffering, physical stability, and protection against incident UV radiation, excessive photosynthetically active...

Failure of Rocks in the Laboratory and in the Earth

Although rocks, at least some of them, are nearly as old as the Earth itself, their behavior continues to play an important role in a variety of applications and phenomena of societal interest. These include natural disasters, such as landslides, volcanic eruptions and earthquakes. Rocks are widely used for building materials, foundations, tunnels and underground facilities. Most of the world’s...

X-ray fluorescence analysis of rare earth elements in rocks using low dilution glass beads.

Major and trace elements (Na, Mg, Al, Si, P, K, Ca, Ti, Mn, Fe, Rb, Sr, Y, Zr, La, Ce, Pr, Nd, Sm, Gd, Dy, Th and U) in igneous rocks were assayed with fused lithium borate glass beads using X-ray fluorescence spectrometry. Low dilution glass beads, which had a 1:1 sample-to-flux ratio, were prepared for determination of rare earth elements. Complete vitrification of 1:1 mixture required heatin...