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<p>When they tested in our area using explosives my brother
collected the wire they used to detonate the charge down the
holes. We spent hours untangling and winding it up on rolls. He
was going to make a telegraph line to the neighbors house a mile
away. Didn't happen but did have a line between our bedrooms. <br>
</p>
<p>Brian CO<br>
</p>
<div class="moz-cite-prefix">On 7/25/2020 9:47 PM, Phil Auten wrote:<br>
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cite="mid:6b797331-e777-50d7-4a28-f501217c210a@basicisp.net">
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<p>The thumpers, or as Geophysical Services Inc. called them,
stompers, replaced the use of explosives for taking readings of
what was down below the surface, particularly oil, and possibly
natural gas. GSI was a division of Texas Instruments where I
worked from 1968 until 1987. We occasionally had articles about
what they were doing in our company newsletter.</p>
<p>Phil in TX<br>
</p>
<br>
<div class="moz-cite-prefix">On 7/25/2020 7:44 PM, Howard Pletcher
wrote:<br>
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<blockquote type="cite"
cite="mid:CANEFi4axGuwtCj0aHwSGGhDP8jj3CjRQUoY=zCXG1XpiiDB6xQ@mail.gmail.com">
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<div class="gmail_default"
style="font-family:tahoma,sans-serif">Very interesting.
Thanks for your info. When I was at IH/Navistar, I know
some trucks were used as thumpers, but had no idea just
what they did--and after a little searching, now see what
is being done, but still don't begin to understand how it
tells the geologists anything. </div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif">Where are the trucks
you worked with built? What engine powers them?</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif">I am continually
amazed by the wide variety of expertise accumulated by us
"dumb farmers that play with old tractors", haven't seen
any brain surgeons on here yet, but I wouldn't be
surprised if one pops up. Very interesting group.</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif">Howard</div>
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<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Sat, Jul 25, 2020 at
1:08 PM ustonThomas Mehrkam <<a
href="mailto:tmehrkam@sbcglobal.net" target="_blank"
moz-do-not-send="true">tmehrkam@sbcglobal.net</a>>
wrote:<br>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div style="font-family:"Helvetica
Neue",Helvetica,Arial,sans-serif;font-size:16px">
<div dir="ltr">The ones we used in the vibrator trucks
were rated for over 300 hp and cost only $32,000
each. We used them to make it easyier to control the
spacing between trucks. Had ultrasonic sensors to
measure the distance between the trucks. They
operated as an array and spacing was important. Some
array designs had different spacing between each
truck.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">The hydrstatic transmission was much
easier to precisely control spacing between trucks.
Three to five trucks in an array was common and there
would be multiple fleets of trucks that would stop
shake the ground then pull up the pad and move forward
to the next shot point. While they were moving
another fleet would shake the ground. Speed things
things up a bit. </div>
<div dir="ltr"><br>
</div>
<div dir="ltr">The older trucks were built on Mac Truck
chases with normal transmissions. Not having a drive
shaft from the front and rear drive allowed putting a
bigger vibrator in the middle to get more signal. </div>
<div dir="ltr"><br>
</div>
<div dir="ltr">In the US the wheeled version is common.
Some places use the tracked version.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">This is the company I use to work for.
The name changed many times. When I joined the name
changed to Geosource that was the name it was know by
for many years.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr"><span><a
href="https://www.inovageo.com/products/category/source-products/vibrators"
rel="nofollow" target="_blank"
moz-do-not-send="true">https://www.inovageo.com/products/category/source-products/vibrators</a></span><br>
</div>
<div dir="ltr"><br>
</div>
<div dir="ltr"><span><a
href="https://www.youtube.com/watch?v=8EVilzqcggk"
rel="nofollow" target="_blank"
moz-do-not-send="true">Seismic Vibrator truck</a></span>
<div><br>
</div>
<div
id="m_-4842885578549511306m_1472968588542696885gmail-m_4105975687844552525ydp799752a1enhancr_card_5974204822"
style="max-width:400px;font-family:YahooSans,"Helvetica
Neue","Segoe
UI",Helvetica,Arial,sans-serif"><a
href="https://www.youtube.com/watch?v=8EVilzqcggk"
style="text-decoration:none;color:rgb(0,0,0)"
rel="nofollow" target="_blank"
moz-do-not-send="true">
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2px 0px 0px;min-height:175px"
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cellspacing="0" cellpadding="0"
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style="background-color:transparent;border-radius:2px
2px 0px
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style="width:100%;min-height:175px"
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<table
style="background:rgb(255,255,255);width:100%;max-width:400px;border-radius:0px
0px 2px 2px;border-top:1px solid
rgb(224,228,233)"
cellspacing="0" cellpadding="0"
border="0" align="center">
<tbody>
<tr>
<td
style="background-color:rgb(255,255,255);padding:16px
0px 16px
12px;vertical-align:top;border-radius:0px
0px 0px 2px"><img
src="https://s.yimg.com/nq/storm/assets/enhancrV2/23/logos/youtube.png"
style="min-width:36px;margin-top:3px" moz-do-not-send="true" height="36"></td>
<td
style="vertical-align:middle;padding:12px
24px 16px
12px;width:99%;font-family:YahooSans,"Helvetica
Neue","Segoe
UI",Helvetica,Arial,sans-serif;border-radius:0px
0px 2px">
<h2
style="font-size:14px;line-height:19px;margin:0px
0px
6px;font-family:YahooSans,"Helvetica
Neue","Segoe
UI",Helvetica,Arial,sans-serif;color:rgb(38,40,42);max-width:314px">Seismic
Vibrator truck</h2>
</td>
</tr>
</tbody>
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</tr>
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</td>
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</tbody>
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</a></div>
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