Sunday, March 18, 2007

Predicting Earthquakes

Scientists believe they have some encouraging news about how and when to predict earthquakes:

Paris - Geophysicists poring over an earthquake hotspot beneath southern Japan believe massive temblors may be preceded by slow, barely perceptible quakes that can last for days or weeks.

In a new paper published in the British journal Nature, the scientists say the warning signs are buried in tiny seismic signals caused by a slip deep within a fault.

Their focus is on phenomena that lie far below the threshold of human sensation called low-frequency earthquakes (LFEs) and non-volcanic tremor.

Seismologists have until now mainly viewed non-volcanic tremor as a weak shaking of the Earth, and LFEs as a swarm of small temblors, with a magnitude of just one or two, that can last for weeks or even months at a time.

These low rumblings are typically found in subduction zones - the regions on the Pacific's "Ring of Fire" that have unleashed the mightiest quakes on record, say the US-Japanese team, led by David Shelly of Stanford University, California.

As someone who has lived in two earthquake prone areas, I say this can only be good news (although, oddly, the only one I've ever felt was in hte UK).

More Google Tools for Webmasters

Google has made some changes to it's reporting tools making life a lot easier for webmasters:

Google has enhanced the reporting capabilities in its Webmaster Tools to show full phrases being used in anchor text, instead of just keywords within the anchor text of links to a site, the company said on its Webmaster Central Blog last night.

Webmaster Tools previously had reports showing the top terms were included in the anchor text other sites are using to link to them. So the list would include the terms "Search," "Engine," and "Watch" when it assesed this link: Search Engine Watch.

With the new reports, the entire phrase will be shown on the list, so the previous link would show up in reports as "Search Engine Watch," which is a much more useful bit of information.

The report is available to verified webmasters who have logged into Google's Webmaster Tools, under the "Statistics" tab, in the "Page Analysis" section. The list of top 100 anchor text phrases can be viewed as a table or downloaded as a csv file.

It's useful to see what anchor text is being used to link to your site, as it provides some insight into what people think of your site, or why they are linking. The anchor text also affects Google's ranking algorithm, so since lots of other sites link to our blog with the term "SEW blog" as anchor text, that affects results for a search on [SEW blog], causing this site to show up at the top of those results.

Now, if only I understood what any of that meant.