Subject: Mystery quake??? No readings???
From: zwolan@nevada.edu (EDWARD ZWOLAN)
Date: 27 Oct 1996 12:16:21 GMT
Hello everyone,
My question is: Is it possible for a properly working seismograph not to
record a small event occuring directly under the measuring equipment?
Example: Very shallow quake whose epicentre is right underneath a
seismograph.
This Wednesday many Las Vegans reported an event of extremely short
duration. Something like a sudden boom from underneath the ground.
Absolutely no waving sensation, no prolonged shaking- nothing of the usual
signs of an earhtquake. The University of Nevada, Las Vegas seismograph
registered nothing!
As I was sitting in front of my computer at the time, the monitor sudenly
jerked like if someone kicked the desk from underneath. That was it!
Nothing else, whatsoever! I am not superstitious, but for a moment I
thought this to be a devilish manifestation, of some sort.
I have a 50 inch long string hanging from the ceiling nearby (there is a
weight attached to its end, and it serves as a crude, but reliable earth
motion detector) -it didn't swing a bit.
What was this event??? Please comment.
Thanx,
S.Zwolan
Subject: Our Planet last Week (18-10 - 25-10) Weekly Journal
From: dennis.van.paassen@tip.nl (State of the Earth Website)
Date: Sun, 27 Oct 1996 18:21:26 GMT
Our planet last week is a weekly journal about natural disasters,
global pollution, and natural and environmental topics.
You can subscribe for free to receive a weekly email copy. If you are
interested just sent an email message to:
dennis.van.paassen@tip.nl
and fill in SUBSCRIBE as subject
You can also visit the State of the Earths Website at url:
http://www1.tip.nl/users/t000208/index.htm
State of the Earth Magazine --- The Creators of Awareness!!
----------------------------------------------------------------------
--Wildfires--
Wildfires started to burn out of control in Southern California
last week, stirred by the first of the seasonal Santa Ana winds
whipping over mountain passes from the Western deserts.
Since the beginning of last week, at least four fires have destroyed
more than 100 homes, forced thousands to evacuate, and scorched more
than 20,000 acres of brush land. Two fires -- one in the northern
San Diego County suburb Carlsbad and the other threatening
celebrity-laden Malibu in Los Angeles County -- burned out of control
Tuesday.
Near Malibu, some 2,500 firefighters worked overnight to
prevent a repeat of 1993's Santa Ana season, when wildfires
that began in brush surrounding the city swept through
residential areas dotted with homes of the rich and famous.
More than 260 structures were destroyed.
Santa Ana winds occur each fall in the western United States
when dry desert winds, triggered by high pressure systems,
push to the west and pick up speed as they squeeze through
narrow mountain passes and canyons.
Under dry conditions in Southern California, the winds fan
autumn wildfires and create dangerous, volatile conditions.
The region's last spate of such fires was in 1993, when 26
major fires killed four people and destroyed or damaged over
1,200 structure, causing nearly $1 billion in damage.
In 1991, a raging wildfire in the Oakland hills killed 24
people, injured 148 and destroyed 3,000 houses and
apartments.
--Tropical Storms--
Lili wich we mentioned also last week, continued, and caused
severe damage on Cuba. 5600 houses were destroyed and big
parts of the sugar-, bananas and coffee harvests are ruined. After
Cuba she went on to the Bahamas whereafter she loosened strenght.
+++
The typhoon Beth killed 4 people at the Fillipine Isle Luzon. Also
vietnam had to suffer from the storm. It brought a lot of rain to the
already flooded land.
+++
The typhoon Carlo brought a lot of rain to the Marinas Islands, after
that he loosened strenght in front of the eastern coast of Japan.
--Earthquakes--
Again Croatia was hit by an earthquake measuring 5.0 on
the Richter Scale. Since one month this area is hit by many
quakes. There were no reports on injuries or deaths. Little
material damage to some historical buildings were reported.
+++
The South-Japanese Isle of Kjoesjoe was hit by one of the
heaviest earthquakes this year. High waves were created and
the coastal areas had to suffer from floods. However there
was not much material damage reported. The earthquake
was measured at 6.6 on the Richter scale.
+++
The earth also moved in the southwestern part of Australia(4,5),
the southern part of Mexico(4,9), the southern part of Alaska(6,1),
and the southeastern part of Wyoming(4,2).
--Floods--
Up to 18 inches of rain hit parts of New England.In parts
of New England Tuesday, flooding from a powerful wee-
kend storm kept dozens of people out of their homes, closed
roads, shut businesses and schools and threatened already
swollen rivers.
The slow-moving storm began to hammer the northeastern
United States on Saturday and over the next three days resulted
in at least five deaths, forced evacuations and sent rivers over
their banks in at least five states. Flooding was expected
to continue in Maine and New Hampshire Tuesday as rivers
crested.
In Portland, Maine, rainwater runoff broke a water supply
pipe, leaving 140,000 area residents without drinking water.
The storm dumped 18 inches of rain in parts of southern
Maine, where bridges were washed out, homes and businesses
flooded and parts of the Maine Turnpike were closed. Gov.
Angus King declared a state of emergency in York, Cumberland
and Oxford counties Monday.
In Massachusetts thousands of people found their homes flooded, their
furniture floating, their cars submerged and streets and roads buried
under several feet of water.
Also New Hampshire had to suffer.The storm produced "the worst
single flooding event" since floods ravaged the state in 1987, said
Gregg
Champlin, spokesman for the New Hampshire Office of Emergency
Management.
----------------------------------------------------------------------
Help Us Get The News
Without the support of its readers, 'Our Planet Last Week' would not
excist. If you have news about earthquakes, volcanos, tropical storms,
floods, pollution etc etc., please report it to our journal.
email: dennis.van.paassen@tip.nl
STATE OF THE EARTH ---- CREATORS OF AWARENESS
http://www1.tip.nl/users/t000208
----------------------------------------------------------------------
Subject: Re: PGA and Mercalli Scale
From: Steven Jaume
Date: Mon, 28 Oct 1996 07:17:52 +1000
This is a multi-part message in MIME format.
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Hein Meidow wrote:
> For detailed information see:
>
> - Murphy, J.R. & O'Brien, L.J. (1977): The correlation of peak ground
> acceleration amplitude with seismic intensity and other physical
> parameters. - Bull.Seism.Soc.America, 67: 877-915
>
> - Trifunac, M.D. & Brady, A.G. (1975): On the correlation of seismic
> intensity scales with the peaks of recorded strong ground motion. -
> Bull.Seism.Soc.America, 65: 139-162
>
> Hein
A more recent paper comparing peak displacements, velocities, and
accelerations is:
Krinitzsky, E.L. and F. K. Chang (1988). Intensity-related earthquake
ground motions, Bull. Assoc. Engineering Geol., 25, 425-435.
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Steven C. Jaume'
Renegade Seismologist Down Under
jaume@shake2.earthsciences.uq.edu.au
The opinions above are purely my own, and do not belong to any of my
employers past, present, and future. They would have to pay me a lot
more for that.
--------------404E48D81044--
Subject: Re: What is the source of geothermal energy??
From: Harold and Lise
Date: Sun, 27 Oct 1996 21:09:57 -0500
kideys@ibm.net wrote:
>
> Hi everyone,
>
> I am fascinated with the idea of using geothermal energy as an
> alternative renewable energy source. But one thing always puzzled me
I worked a lot on this when I was doing rock mechanics in university in
'79. It has a lot of serious problems and will probably never be that
common. Some areas are naturals, and are already being exploited, but a
lot of pumping causes earthquakes (relevance here!). It was thought
that you could apply this everywhere, since from anywhere you'll find
hot, dry rock if you drill deep enough. Alas, we did lots of work on
hot dry rock heat extraction. You have to drill deep, and you have to
crack the rock, and cracks never go where you want them to, so it's
tough to intersect the holes. Then you pump a lot of water, but the
cracks clog up. I really don't think you get more energy back then you
put into it. ps. the heat comes from radioactive decay.
Harold Asmis (at home)
Subject: Re: Mystery quake??? No readings???
From: "Paul Britton Jr."
Date: 28 Oct 1996 02:35:27 GMT
Good Evening,
You a fan of The X-Files? Perhaps it was a sort of a government
experiment...or something to that effect? Anyone have a schedule of
military testings in the Desert Southwest?
Paul Britton Jr.
EDWARD ZWOLAN wrote in article
<54vjql$hl4@news.nevada.edu>...
>
> Hello everyone,
>
> My question is: Is it possible for a properly working seismograph not to
> record a small event occuring directly under the measuring equipment?
>
> Example: Very shallow quake whose epicentre is right underneath a
> seismograph.
>
>
> This Wednesday many Las Vegans reported an event of extremely short
> duration. Something like a sudden boom from underneath the ground.
> Absolutely no waving sensation, no prolonged shaking- nothing of the
usual
> signs of an earhtquake. The University of Nevada, Las Vegas seismograph
> registered nothing!
>
> As I was sitting in front of my computer at the time, the monitor sudenly
> jerked like if someone kicked the desk from underneath. That was it!
> Nothing else, whatsoever! I am not superstitious, but for a moment I
> thought this to be a devilish manifestation, of some sort.
>
> I have a 50 inch long string hanging from the ceiling nearby (there is a
> weight attached to its end, and it serves as a crude, but reliable earth
> motion detector) -it didn't swing a bit.
>
> What was this event??? Please comment.
>
> Thanx,
> S.Zwolan
>
Subject: Re: Mystery quake??? No readings???
From: Bill Oertell
Date: Sun, 27 Oct 1996 20:43:53 -0800
EDWARD ZWOLAN wrote:
>
> Hello everyone,
>
> My question is: Is it possible for a properly working seismograph not to
> record a small event occuring directly under the measuring equipment?
>
> Example: Very shallow quake whose epicentre is right underneath a
> seismograph.
>
> This Wednesday many Las Vegans reported an event of extremely short
> duration. Something like a sudden boom from underneath the ground.
> Absolutely no waving sensation, no prolonged shaking- nothing of the usual
> signs of an earhtquake. The University of Nevada, Las Vegas seismograph
> registered nothing!
>
> As I was sitting in front of my computer at the time, the monitor sudenly
> jerked like if someone kicked the desk from underneath. That was it!
> Nothing else, whatsoever! I am not superstitious, but for a moment I
> thought this to be a devilish manifestation, of some sort.
>
> I have a 50 inch long string hanging from the ceiling nearby (there is a
> weight attached to its end, and it serves as a crude, but reliable earth
> motion detector) -it didn't swing a bit.
>
> What was this event??? Please comment.
>
> Thanx,
> S.Zwolan
You probably experienced a sonic boom, the sound of an aircraft
travelling faster than the speed of sound.
Bill
Subject: Re: What is the source of geothermal energy??
From: cheshire@ridgecrest.ca.us (Dr Pepper)
Date: Mon, 28 Oct 1996 16:36:08 GMT
On Sun, 27 Oct 1996 21:09:57 -0500, Harold and Lise
wrote:
>kideys@ibm.net wrote:
>>
>> Hi everyone,
>>
>> I am fascinated with the idea of using geothermal energy as an
>> alternative renewable energy source. But one thing always puzzled me
>
>I worked a lot on this when I was doing rock mechanics in university in
>'79. It has a lot of serious problems and will probably never be that
>common. Some areas are naturals, and are already being exploited, but a
>lot of pumping causes earthquakes (relevance here!). It was thought
>that you could apply this everywhere, since from anywhere you'll find
>hot, dry rock if you drill deep enough. Alas, we did lots of work on
>hot dry rock heat extraction. You have to drill deep, and you have to
>crack the rock, and cracks never go where you want them to, so it's
>tough to intersect the holes. Then you pump a lot of water, but the
>cracks clog up. I really don't think you get more energy back then you
>put into it. ps. the heat comes from radioactive decay.
>
>Harold Asmis (at home)
Well, China Lake has had a Geothermal Co-generation plant for over
ten years now. It supplies most of the electricity for the Base,
and I understand they also sell it back to PGE (or who ever :)
Also, what about Klamath Falls, Oregon? I understand that the
whole city uses geothermal steam for heating, , ,???
Dr Pepper
10 - 2 - 4
Good Anytime
Subject: Re: What is the source of geothermal energy??
From: karish@pangea.Stanford.EDU (Chuck Karish)
Date: 28 Oct 1996 19:43:55 GMT
In article <3276e018.1304139@news.ridgecrest.ca.us>,
Dr Pepper wrote:
>Well, China Lake has had a Geothermal Co-generation plant for over
>ten years now. It supplies most of the electricity for the Base,
>and I understand they also sell it back to PGE (or who ever :)
>Also, what about Klamath Falls, Oregon? I understand that the
>whole city uses geothermal steam for heating, , ,???
You're talking about plants in active volcanic areas with
a pre-existing hot water circulation. The post you replied
to was about hot dry rock projects, which have a different set of
technical problems.
Even where there are plenty of hot springs, geothermal energy
isn't free - the stuff that comes up out of the ground is corrosive
and poisonous. The capital cost and the operating cost are high
compared to other means of energy production, offsetting much of
the savings in fuel cost. The biggest problem is one of scale -
it takes a huge geothermal field with lots of turbines to match
the output of a single gas-fired plant.
--
Chuck Karish karish@mindcraft.com
(415) 323-9000 x117 karish@pangea.stanford.edu
Subject: Re: What is the source of geothermal energy??
From: cheshire@ridgecrest.ca.us (Dr Pepper)
Date: Mon, 28 Oct 1996 22:15:11 GMT
On 28 Oct 1996 19:43:55 GMT, karish@pangea.Stanford.EDU (Chuck
Karish) wrote:
>In article <3276e018.1304139@news.ridgecrest.ca.us>,
>Dr Pepper wrote:
>>Well, China Lake has had a Geothermal Co-generation plant for over
>>ten years now. It supplies most of the electricity for the Base,
>>and I understand they also sell it back to PGE (or who ever :)
>>Also, what about Klamath Falls, Oregon? I understand that the
>>whole city uses geothermal steam for heating, , ,???
>
>You're talking about plants in active volcanic areas with
>a pre-existing hot water circulation. The post you replied
>to was about hot dry rock projects, which have a different set of
>technical problems.
>
>Even where there are plenty of hot springs, geothermal energy
>isn't free - the stuff that comes up out of the ground is corrosive
>and poisonous. The capital cost and the operating cost are high
>compared to other means of energy production, offsetting much of
>the savings in fuel cost. The biggest problem is one of scale -
>it takes a huge geothermal field with lots of turbines to match
>the output of a single gas-fired plant.
>--
>
> Chuck Karish karish@mindcraft.com
> (415) 323-9000 x117 karish@pangea.stanford.edu
Thank you for pointing out my mis-read of the thread. However,
despite what type of field it is, I must wonder why the Navy would
run this Geo T plant for so long if it is as inefficient and
costly as you say it is? Also, we have been having a bunch of
earthquake swarms in this area, and when the Navy was asked about
the plant removing the steam, they said that they were inserting
an equal volume of water so as to offset any seismic activity.
Interesting. Hhmmmmm !
Dr Pepper
10 - 2 - 4
Good Anytime
Subject: New Technology to Help Measurement and Study of Earthquakes
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Date: 28 Oct 1996 22:36 UT
Douglas Isbell
Headquarters, Washington, DC October 28, 1996
(Phone: 202/358-1753)
Mary Hardin
Jet Propulsion Laboratory, Pasadena, CA
(Phone: 818/354-5011)
Cheryl Dybas
National Science Foundation, Arlington, VA
(Phone: 703/306-1070)
Don Kelly
U.S. Geological Survey, Reston, VA
(Phone: 703/648-4466)
RELEASE: 96-218
NEW TECHNOLOGY TO HELP MEASUREMENT AND STUDY OF EARTHQUAKES
Scientists have begun installing a network of 250 Global
Positioning System (GPS) receivers that will continuously
measure the constant, yet physically imperceptible, movements
of earthquake faults throughout southern California. This
information, which in many cases will be gathered and
analyzed with the help of local students, should help
researchers forecast future earthquake hazards in the greater
Los Angeles area.
NASA Administrator Daniel S. Goldin dedicated a new site
in the Southern California Integrated GPS Network (SCIGN)
today at Rialto High School, before a demonstration of the
technology to science students from the school. Goldin was
accompanied by U.S. Representative George Brown (D-CA), the
ranking minority leader of the House Science Committee, and
representatives from the National Science Foundation and the
U.S. Geological Survey.
"This network is a tremendous example of how technology
developed for space benefits life on Earth. This interagency
project will give us detailed information never before
available to track the invisible geologic strains and
stresses that lie beneath the California landscape," Goldin
said. "Such data should give us fresh insight into the
forces that produce earthquakes, and could one day help
reduce the loss of life and property from such disasters."
GPS uses data transmitted from a constellation of 24
Earth-orbiting satellites that are jointly governed by the
departments of Defense and Transportation. The satellites
are arranged so that several of them are "visible" from any
point on the surface of the Earth at any time. A user on the
ground using a GPS receiver can determine the site's precise
location by coordinating the signals from the satellites.
"The surface of the Earth is constantly moving and
southern California is being squeezed in the process. The
GPS network will continuously measure movements of the
Earth's crust with a precision of one millimeter per year,
which will show us where strain is building up," said Dr.
Andrea Donnellan, a member of the SCIGN coordinating
committee at NASA's Jet Propulsion Laboratory (JPL),
Pasadena, CA.
"GPS is the most important new technology to emerge for
the study of earthquakes in decades. This information will
permit us to improve our estimates of the regional earthquake
hazard in southern California and to prioritize earthquake
mitigation activities, including emergency preparedness and
retrofit strategies," said Dr. Tom Henyey, director of the
USGS-NSF Southern California Earthquake Center (SCEC) in Los
Angeles. "Continuous GPS measurements also will allow for
more rapid regional damage assessment following large earthquakes."
The earthquake network began in 1990 with only four GPS
receivers as a prototype project funded by NASA. It detected
very small motions of the Earth's crust in southern
California associated with the June 1992 Landers and the
January 1994 Northridge earthquakes. "The GPS receivers
operating during the Landers earthquake were able to detect
for the first time a subtle change in the regional
deformation pattern, which is potentially of great importance
for studying the physics of earthquakes and hazards
mitigation" said Dr. Yehuda Bock, a SCIGN executive board
member from Scripps Institution of Oceanography, University
of California, San Diego.
Currently, the SCIGN has 40 GPS receivers up and
running, with the remaining receivers scheduled to be
installed over the next three years.
"With data from the 40 receivers, we have determined
that southern California has continued to move since the
Northridge quake in 1994. This may mean that stress is being
relieved in part without earthquakes, which may reduce the
overall earthquake hazard," JPL's Donnellan said. "We will
try to determine if other faults have been loaded as a result
of the earthquake."
"The survey data are particularly important for
identifying active buried faults that do not reach the ground
surface. Such faults may be common in the Los Angeles
metropolitan region," said Dr. David Jackson, science
director of SCEC.
The GPS measurements also will be useful to characterize
earthquake damage. "The network will help agencies monitor
important structures. GPS receivers placed on or near dams,
bridges and buildings would allow off-site detection of
probable damage to those structures. We are collaborating
with Los Angeles County in a pilot study of continuous GPS
monitoring of Pacoima Dam," said Dr. Ken Hudnut, SCIGN
executive board member at the U.S. Geological Survey in Pasadena.
Many of the receivers are being placed at schools so
that students can be involved in the experiment. SCEC's
"Global Science Classroom" at the University of Southern
California has formed a partnership with JPL, several school
districts and educators' groups to develop a science unit for
use in schools. The unit, titled "The Elastic Planet," will
give students access to the data being gathered by the network.
"This network is a model of interagency cooperation
between NASA, the U.S. Geological Survey and the National
Science Foundation, as well as with local governments and
schools," Goldin said. "Students will get hands-on science
experience in using real data. It should ignite their
enthusiasm for science while providing a genuine public service."
SCIGN is a consortium of institutions with a common
interest in using GPS for earthquake research and mitigation.
The consortium is coordinated by the SCEC, a National Science
Foundation Science and Technology Center headquartered at the
University of Southern California. The lead institutions in
the installation and operation of SCIGN are: JPL, the
Institute of Geophysics and Planetary Physics-Scripps
Institution of Oceanography at the University of California,
San Diego, the United States Geological Survey, the
University of California, Los Angeles and USC.
-end-
Subject: Re: What is the source of geothermal energy??
From: hatunen@netcom.com (DaveHatunen)
Date: Mon, 28 Oct 1996 22:46:26 GMT
In article <32752eaf.21423496@news.ridgecrest.ca.us>,
Dr Pepper wrote:
>On 28 Oct 1996 19:43:55 GMT, karish@pangea.Stanford.EDU (Chuck
>Karish) wrote:
[...]
>>Even where there are plenty of hot springs, geothermal energy
>>isn't free - the stuff that comes up out of the ground is corrosive
>>and poisonous. The capital cost and the operating cost are high
>>compared to other means of energy production, offsetting much of
>>the savings in fuel cost. The biggest problem is one of scale -
>>it takes a huge geothermal field with lots of turbines to match
>>the output of a single gas-fired plant.
>Thank you for pointing out my mis-read of the thread. However,
>despite what type of field it is, I must wonder why the Navy would
>run this Geo T plant for so long if it is as inefficient and
>costly as you say it is?
Are you seriously asking why a branch of the military would do
something inefficient and costly?
Back in the 1960s when I was in the Army at Fort Knox, I was on a
rotation for fire duty. The post had a number of old wooden barracks
with coal furnaces, and it was the fireman's job to go around during
a day and night and keep the furnaces going, either keeping them stoked
during cold weather or banking them during warmer weather. At one
cluster of barracks, as I was shoveling coal and breathing sulfurous
fumes from the furnace, I could clearly see just 50 yards away a couple
of natural gas wells. Why didn't the Army use the gas wells on the post
instead of buying coal from Appalachia? Because, I was told, the Army
had a long term contract with a coal company, written many, many years
before gas was discovered on the post.
--
********** DAVE HATUNEN (hatunen@netcom.com) **********
* Daly City California *
* Between San Francisco and South San Francisco *
*******************************************************
Subject: Re: What is the source of geothermal energy??
From: kideys@ibm.net
Date: 29 Oct 1996 10:59:52 GMT
In , hatunen@netcom.com (DaveHatunen) writes:
>In article <54too2$17sa$2@news-s01.ny.us.ibm.net>, wrote:
>>Hi everyone,
>>
>>I am fascinated with the idea of using geothermal energy as an
>>alternative renewable energy source. But one thing always puzzled me and
>>that is what is driving this heat engine deep within the earth. The moon
>>as far as I know is geothermally dead so there is no rule that all heavenly
>>bodies have geothermal energy.
>
>The earth's internal heat is largely created by decay of radioactive
>elements.
>
>[...]
>
>
>
>
>--
>
>
> ********** DAVE HATUNEN (hatunen@netcom.com) **********
> * Daly City California *
> * Between San Francisco and South San Francisco *
> *******************************************************
>
> The source of the earth's heat is its radioactive isotopes --
> principally 40K (potassium 40), 235U and 238U, and 232Th.
>
> Since most of these have half-lives of many billions of years
> (exception is 235U, with halflife of hundreds of millions
> of years), don't expect a *geothermal* cool-down soon.
Thank you for the reply. No doubt that this geothermal heat source
cannot be any kind of conventional chemical energy. But if this originated
from massive amounts of radioactive heavy metals and potassium deep within
the earth wouldn't there be a greater presence of radioactivity in lava and
magma coming from volcanic eruptions and submarine fissures?
Even if all of the alpha and beta particles are absorbed way below the crust
and bedrock, what about gamma radiation and neutrinos or other rays caused
by radioactivity which can penetrate all that rock? Has anyone put forward
a theory suggesting slow nuclear fusion? Under enough pressure and with
the right materials this may be a possibility. I would be very interested
in references of the latest research in this area. Thank you.
Ahmet Kideys
Subject: Re: What is the source of geothermal energy??
From: Eylon Shalev
Date: Tue, 29 Oct 1996 10:12:16 -0500
DaveHatunen wrote:
>
> In article <32752eaf.21423496@news.ridgecrest.ca.us>,
> Dr Pepper wrote:
> >On 28 Oct 1996 19:43:55 GMT, karish@pangea.Stanford.EDU (Chuck
> >Karish) wrote:
>
> [...]
>
> >>Even where there are plenty of hot springs, geothermal energy
> >>isn't free - the stuff that comes up out of the ground is corrosive
> >>and poisonous. The capital cost and the operating cost are high
> >>compared to other means of energy production, offsetting much of
> >>the savings in fuel cost. The biggest problem is one of scale -
> >>it takes a huge geothermal field with lots of turbines to match
> >>the output of a single gas-fired plant.
>
> >Thank you for pointing out my mis-read of the thread. However,
> >despite what type of field it is, I must wonder why the Navy would
> >run this Geo T plant for so long if it is as inefficient and
> >costly as you say it is?
>
> Are you seriously asking why a branch of the military would do
> something inefficient and costly?
The Navy don't run the geothermal power plant in Coso (china Lake).
The Navy owns the land and collects royalties from California
Energy (CECI), the public company (CE on the NYSE) that invested
in and is operating the geothermal power plant. Both sides, the
Navy and CECI, are making money on this "inefficient and costly"
program. I know that the military is an easy target but in this
case it's the wrong target.
Eylon
Subject: Re: loma prieta
From: hatunen@netcom.com (DaveHatunen)
Date: Tue, 29 Oct 1996 15:30:22 GMT
In article <553ppp$ns9@newsbf02.news.aol.com>, Bjarcia wrote:
>I wonder why it didnt cause as much damage here ( near where the loma
>prieta hit) than the kobe quake did to kobe when the official mag. is
>lower in kobe than in loma prieta?
You don't say where "here" is for you. But the Loma Prieta quake
occurred tens of kilometers from major population centers, while the
Kobe quake was very close to high denisty urban area. And, too, the
people in Santa Cruz and Watsonville might not agree that the Loma
Prieta quake didn't do much damage; the downtown area of Santa Cruz has
not yet been rebuilt in any substantial manner.
It didn't help that Kobe is largely built on soil like San Francisco's
Marina District and Oakland's Cypress Freeway Structure, both of which
took major hits.
Ironically, too, despite all the publicity about Japanese
quake-awareness, it appears that their construction standards weren't
what they needed to be.
--
********** DAVE HATUNEN (hatunen@netcom.com) **********
* Daly City California *
* Between San Francisco and South San Francisco *
*******************************************************
Subject: Re: What is the source of geothermal energy??
From: "H.W. Stockman"
Date: Tue, 29 Oct 1996 09:36:13 -0700
kideys@ibm.net wrote:
> > Since most of these have half-lives of many billions of years
> > (exception is 235U, with halflife of hundreds of millions
> > of years), don't expect a *geothermal* cool-down soon.
> Thank you for the reply. No doubt that this geothermal heat source
> cannot be any kind of conventional chemical energy. But if this originated
> from massive amounts of radioactive heavy metals and potassium deep within
> the earth wouldn't there be a greater presence of radioactivity in lava and
It may take "massive amounts", but it doesn't take
high concentrations. The earth had initial heat
from accretion (probably), and it is large, so it takes
a long time to lose its heat; the balance of loss and
production gives us the quasi-steady state we have now.
The speculated total amounts of K, U and Th for the
*bulk* earth are similar to the amounts in chondritic
meteorites, and lavas do have ppm amounts of U and Th,
and up to several percent K. There has always been
some debate about the amount of "missing" K in the
earth, and some speculation it is in the core.
Subject: Re: loma prieta
From: astephan@presby.edu (Andrew Stephan)
Date: Tue, 29 Oct 1996 16:29:24 GMT
In article <553ppp$ns9@newsbf02.news.aol.com>, Bjarcia wrote:
>I wonder why it didnt cause as much damage here ( near where the loma
>prieta hit) than the kobe quake did to kobe when the official mag. is
>lower in kobe than in loma prieta?
>
The Kobe quake was a lot closer to the city than Loma Prieta was to San
Fransisco. The buildings most affected were old, weakly built buildings
with masonry roofs. Kobe was fairly shallow, I think, intensifying the
shaking. The big areas of fill (ground) were much closer to the Kobe
epicenter than than the San Fransiscan areas were to Loma Prieta. San
Fransisco had a signifigantly higher percentage (I think) of solidly
built wooden houses. More people live in the Kobe-Osaka-Kyoto area (16
million) than do in the San Fransisco Bay area (6 million). Most deaths
were in the weak, traditional Japanese houses. The quake was at night
when people were asleep. Perhaps if they'd been at work in newer
buildings... (Note: people are usually safer in their homes, but this
depends on how strong local homes are relative to local non-residential
buildings, among other things.)
Andrew
>
>
>
>BJ
>
>"Lift your head to the sky
>And keep tryin'
>Believe in You
>And it will take you higher"
>-- Groove Theory
Subject: Re: What is the source of geothermal energy??
From: karish@pangea.Stanford.EDU (Chuck Karish)
Date: 30 Oct 1996 03:08:24 GMT
In article <32752eaf.21423496@news.ridgecrest.ca.us>,
Dr Pepper wrote:
>Thank you for pointing out my mis-read of the thread. However,
>despite what type of field it is, I must wonder why the Navy would
>run this Geo T plant for so long if it is as inefficient and
>costly as you say it is?
The big issue I see is that geothermal doesn't scale as readily as
other technologies do. Special-purpose small plants in remote areas
have economics that differ from more urban ones, like the Geysers
field in northern California. Too, this one is a cogeneration plant
of some sort, meaning that there's an economic use for the low-quality
waste steam from the generators.
>Also, we have been having a bunch of
>earthquake swarms in this area, and when the Navy was asked about
>the plant removing the steam, they said that they were inserting
>an equal volume of water so as to offset any seismic activity.
Bureaucratic residue of publicity from Rocky Flats. The induced
earthquakes there (caused by injection of nerve gas by-products
or some such noxious stuff) were very small.
Another reason to re-inject water is to get rid of the toxic
chemicals that come up with the steam.
--
Chuck Karish karish@mindcraft.com
(415) 323-9000 x117 karish@pangea.stanford.edu
Subject: Re: What is the source of geothermal energy??
From: davis@miphys.physics.lsa.umich.edu (Brian Davis)
Date: Tue, 29 Oct 1996 22:44:25 -0400
In an article, "kideys" wrote:
> But if this originated from massive amounts of radioactive heavy metals and
> potassium deep within the earth wouldn't there be a greater presence of
> radioactivity in lava and magma coming from volcanic eruptions and submarine
> fissures?
Good point, but most of these elements are concentrated in the crust,
not in the core or mantle of the Earth. In fact the heat per unit volume
in the crust is roughly 2 orders of magnitude greater than than in the
mantle. The heat budget of the Earth is still dominated by the mantle
because the volume is so much larger (only 1/5 of the Earth's total heat
is produced in the crust).
> Even if all of the alpha and beta particles are absorbed way below the crust
> and bedrock, what about gamma radiation and neutrinos or other rays caused
> by radioactivity which can penetrate all that rock?
The material is very dilute - essentially the rock is self-shielding,
and very little radiation gets "out", so to speak. Some of the background
radiation at the surface is due to rock, but only surface rock - very
little is due to rocks deeper than a few feet. To give an idea of the
dilute nature of the radioisotopes, for Granite, Uranium is only 4 ppm,
Potassium 3.5 ppm, and Thorium 15 ppm - their total heat output is only
about 1.0e-9 W/kg, tiny.
> Has anyone put forward a theory suggesting slow nuclear fusion? Under enough
> pressure and with the right materials this may be a possibility.
I've heard several people express this, but to my knowledge it's not
possible with any material. Fusion can occur in many materials (fusion
will result in a net release of energy for any elements up to Iron), but
the larger the atomic number, the higher temperatures and pressures
required (in general). Even for heavy isotopes of Hydrogen, this is not
even remotely attained in the Earth's core. At the sun's core, pressures
are at least 4.5e+8 Atm, and temperatures around 1.6e+7 deg-K. The
corresponding values for the Earth are around 3.6e+6 Atm and 4.0e+3 deg-K.
These are rough figures only, but clearly no where *near* that needed for
fusion.
-Brian Davis
Subject: Re: What is the source of geothermal energy??
From: karish@pangea.Stanford.EDU (Chuck Karish)
Date: 30 Oct 1996 08:18:41 GMT
In article ,
Brian Davis wrote:
>To give an idea of the
>dilute nature of the radioisotopes, for Granite, Uranium is only 4 ppm,
>Potassium 3.5 ppm, and Thorium 15 ppm - their total heat output is only
>about 1.0e-9 W/kg, tiny.
I calculate 3.8 parts per thousand of K40 in granite. Your number for
uranium strikes me as low, too. These numbers are closer to the
average values for the continental crust, which does not have a
granitic composition.
I seem to remember that the Earth's average heat flow is on the order
of a watt per square meter. If the number given above for average
heat output is accurate, enough heat is produced in the top two
kilometers of continental crust to account for the Earth's entire
heat flow.
--
Chuck Karish karish@mindcraft.com
(415) 323-9000 x117 karish@pangea.stanford.edu
Subject: The Re-birth of the Hammer
From: Harold Asmis
Date: Wed, 30 Oct 1996 10:11:52 -0500
An interesting week for me. We had funded Carlton University to do some
hammer seismic surveys around the seismometers of the Southern Ontario
Seismic Network (SOSN). The intent was to get accurate shear wave
velocities for a couple of hundred metres under the site.
For background, hammer seismics have been around since I was a kid in
university. The idea is to lay out a string of geophones and whap the
ground with a sledgehammer. You record the waves and calculate the
velocities of the layers. In the 80's it was never very successful if
you wanted to do something serious. We even resorted to using a
modified shotgun for a source. For shear waves we had to rely on very
expensive cross-hole measurements.
So when the proposal to do this came around, I was skeptical, but we
gave it a chance. It's amazing what 20 years of technological
improvement can do! We're using a very fancy stacking recorder,
generously loaned by the GSC, and horizontal geophones. The hammer is
whapped sideways against a big, partially buried I-beam, to generate
shear waves, and the different polarities (two ways to whap it) are run
for checking. The stacking recorder builds up a number of whacks to
reduce noise.
Way out in the country we got really good penetration. The real test
came when we did it in the front lawn of an operating nuclear power
station. 6 reactors put out a lot of noise. But you just had to
increase the number of whacks to 15, and it produced good results.
We should hope to have the full report on the SOSN web site soon.
--
Harold W. Asmis harold.w.asmis@hydro.on.ca
tel 416.592.7379 fax 416.592.5322
Standard Disclaimers Apply
Subject: Re: PGA and Mercalli Scale
From: e_rmwm@va.nmh.ac.uk (Roger Musson)
Date: Tue, 29 Oct 1996 11:09:41
In article <54qhme$5hm@news.unocal.com> stgprao@sugarland.unocal.COM (Richard
Ottolini) writes:>From: stgprao@sugarland.unocal.COM (Richard Ottolini)
>Subject: Re: PGA and Mercalli Scale
>Date: 25 Oct 1996 14:09:18 GMT
>In article , Andrew Stephan wrote:
>>I asked this question earlier, but didn't get a response. What is the
>>correlation between Peak Ground Acceleration (PGA) and the Mercalli
>>scale? I realize that the corelation wouldn't be exact - an earthquake
>>can be very brief with a high PGA and cause less damage than one with a
>>lower PGA but a much greater length. If someone could give me an
>>average and perhaps even a general sort of range for the different
>>Mercalli scale numbers, that would be very nice. Thanks!
>Bolt, Appendix C:
>Mercalli gravities
>IV .015-.02
>V .03-.04
>VI .06-.07
>VII .1-.15
>VIII .25-3
>IX .5-.55
>X .6+
>XI blank
>XII >1
Please be aware that the Mercalli Scale has only ten degrees (actually the
first of his two scales had only six). Sorry to be a pedant, but if you mean
the Modified Mercalli Scale you should say so (and say which version, as there
is a considerable variety, and they are not necessarily compatible).
In addition, correlations between intensity and pga are notoriously unreliable
and best avoided altogether. As has been said before, acceleration of 1g for
0.01 sec = no damage, acceleration of 0.1 g for 30 mins = wipeout.
Roger Musson
British Geological Survey
e_rmwm@va.nmh.ac.uk