On 07/14/2012 12:38 AM, Thomas Dick wrote:
> On 7/13/2012 5:55 PM, Dave Nelson wrote:
>> The number of possible seismic instrument configurations which will 
>> provide some response  to seismic motions is vast. The question is 
>> the practicality/utility of a given configuration.
>> The key figure of merit for any instrument configuration  is the 
>> instrument self noise and response as a function of frequency. This 
>> directly determines the minimum seismic motion the instrument is 
>> capable of detecting and then providing useful data for analysis.
>> If one is willing to wait for that rare magnitude 7 or 8 event the 
>> simplest / noisiest instrument may do the job in some contexts, such 
>> as classroom demonstrations .
>> The amateur astronomer community has evolved to the point where it 
>> provides useful  ( if not essential) information to the astronomy 
>> scientific community. I believe the amateur seismology community 
>> could do a similar service but not with inadequate instrumentation.
>>  The goal should be to develop amateur instruments with 
>> characteristics near the performance of professional instruments and 
>> then operating  them in reasonably low noise sites. (An instrument in 
>> a residential basement  will work reassembly well if carefully done.)
>> Larry Cochrane has  already provided us with  excellent equipment to 
>> handle the sensor data and connect it to a network. Some work needs 
>> to be done in this area but we have a good start.
>> _*My challenge is to include instrument self noise and generator 
>> constant, both as a function of frequency, as a FIRST PRIORITY when 
>> evaluating  the utility of an instrument concept. *_
>> Just another gadget that will respond if you shake it is not where we 
>> want to spend our efforts and resources.
>> I do  NOT  mean to imply there are not some truly innovative and 
>> possibly revolutionary ideas out there but we should  look at each of 
>> them  carefully to determine early whether they justify significant 
>> effort or belong in the "that was interesting" stack.
>> Just where determination is made is a personal choice but it should 
>> be based on some form of analysis and/or test.
>> Comments Please.
>> Dave Nelson
>> Rolling Hills Estates, California
> My impression is that most academia and professional seismologists 
> hold the amateur in very low esteem.

Yes, they do hold us in low esteem and this is our own fault.

We have noisy instruments
We do not calibrate
We do not have accurate time
We do not use a standard format for data exchange
We do not use standard naming conventions

The academic and professional seismologists can already locate and 
characterize (within a few minutes) all events over about 4.2 Mb, They 
don't need us for that.  Where we could excel and make a meaningful 
contribution is in the seismicity of our own backyards, the small events 
less than one degree from our instruments. Recording those is a bit 
harder than picking up the squiggles from a 6.5 Mb 10 degrees away.

These are just a few things we do and do not do and until we do we will 
just be amateurs.

Just my two cents

Angel




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