Taxonomy term

may 2015

Geologic Column: On the Summer Solstice

Today, we can only speculate on the significance that the summer solstice had for our ancestors, but we do know its scientific meaning. The author ruminates on the longest day of the year in the Northern Hemisphere, and its place in our annual journey around the sun.
21 Jun 2015

Counting 'tree' rings in fish skulls provides climate clues

Most fish have little structures in their skulls that record growth patterns — periods of feast and famine — just like tree rings. Now, scientists are using these structures, called otoliths, to show how fish size may decrease as a result of a changing ocean. 

16 Jun 2015

Pre-settlement erosion rates illuminated

Humans are one of the most powerful erosive agents on Earth, moving copious amounts of sediment to and fro, mainly through agriculture and development. But quantifying how much we actually move — often a necessary step for developing sustainable land management practices — hinges on determining erosion rates in an area before humans intervened. A new study using surface exposure dating to estimate pre-colonial erosion rates in the southeastern U.S. has now clarified the natural background rate in more detail than ever before, revealing the dramatic human impact on the regional landscape.

 
31 May 2015

Mineral Resource of the Month: Iron oxide pigments

Iron oxide pigments, natural or synthetic, are inorganic materials commonly used as coloring agents. They are valued for their resistance to color-change (especially from exposure to sunlight), chemical resistance, stability under ambient environmental conditions, nontoxicity and relatively low cost.

 
29 May 2015

California's big trees dying of thirst

From the days of John Muir’s treks through the valleys and peaks of the Sierra Nevada, California’s majestic forests have attracted nature lovers from around the world. Since Muir’s death in 1914, though, dramatic changes have taken hold. Across the state’s forests, small trees are more common while large trees have declined in number, and oaks seem to be taking over where pines once ruled. A new study cites drought due to warming as a major driving force behind these changes.

29 May 2015

Geomedia: On the web: Personalizing drought data with digital tools

With drought, people feel the heat while it’s happening, but understanding how current droughts fit into past trends — and what they mean for the future — is harder to grasp. Several online tools are available to help the public and decision-makers make sense of drought data. Viewers can see current and historical droughts superimposed on maps, focusing in on specific locations or broadening the view to larger regional, national or global droughts. 
28 May 2015

Rock stars: Geologists on the silver screen

Good guys or bad guys? A team of geologists investigates how their profession is portrayed on film.

26 May 2015

And best picture goes to...'Dante's Peak'

Our favorite cult geologist movie is “Dante’s Peak,” released in 1997. It is a good representation of the last few decades of disaster movies, and it is arguably the best and most realistic geologist movie to date.

26 May 2015

Comment: The new frontier: Homesteading on Mars

Once relegated to science fiction, the idea of humans colonizing Mars could become a reality. But the lack of an international agreement governing the colonization of other planets challenges us to think about how to use the resources of space fairly, efficiently and ethically.
25 May 2015

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