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Interview :09 - 25:35 Play :09 - More
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Tony Coates, Jeremy Jackson  

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Geology; Paleobiology  

Environmental Recording 25:35 - 31:00 Play 25:35 - More
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Walking through river  

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Interview 32:30 - 48:30 Play 32:30 - More
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Tony Coates, Jeremy Jackson  

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Geology; Paleoecology  

NPR/NGS Radio Expeditions
25 Mar 1995

    Geography
  • Panama
    Darién
    Locality
  • Rio Yape
    Latitude/Longitude
  • 8.06841   -77.31982
    Habitats
  • River
    Channels
  • Stereo
    Sampling Rate
  • 48kHz
    Bit Depth
  • 16-bit
    Recorders
  • SONY TCD-D7
    Microphones
  • Sennheiser MKH 30
  • Sennheiser MKH 40
    Accessories
    Equipment Note
  • Stereo=1; Decoded MS stereo; Sennheiser MKH40 Cardioid Mid Mic and MKH30 Bidirectional Side Mic

NPR/National Geographic RADIO EXPEDITIONS
"Oceans of Life"
PANAMA Logs Darien DAT # 3
MS -stereo -Sennheiser 40 & 30

Day Hike: Tony and Jeremy at work by the river -very hot good tape of Tony Coates digging and talking about fossil work. Work is right by the river so it's quite a prominent sound in the background.
0:00:51 -FX -River Ambi plus walking along in the rocks .... ** 0:01:32 TC -Clear off the top of the bed and I need a surface on which I can place my board. Then I get out my brunt and compass, and the way a geologist figures out which way the rocks are dipping is to measure first of all a line across the board that is horizontal and then by definition the line that is at right angles going down hill from that horizontal line will be the direction in which the stratum is dipping most steeply....and that's by convention the direction and then the inclination that you measure to orient the bed in space.....so here the bed is dipping downhill at its maximum in the direction of 160 degrees... and then when I put my compass over that, it's dipping at 15 degrees ..... so I write on my map 15 over 160, and that will tell any other geologist looking at the map the orientation in space of the rocks that we're dealing with here.......so in fact I was wrong, the rocks are young to the east and getting older to the west .....Let me have a look at one of these *FX....hammering..... *Now you can see when I knock a piece off the color is quite different inside the rock than out, and you can in fact see that there are lots of little fossils in there, little white specks that turn out to be small pieces of shell, which is encouraging because we can out of here some microscopic plankton....and these are the things we can use to date the rocks (3:52)
And this looks a volcanic sandstone... So I'm going to note down the kind of rock I have and the orientation in space, and then we'll just consistently do this as we go down the river.....Now because these rivers are very poorly mapped..... so what I will do now as well as recording the kind of rock and its orientation, I will now measurethe direction of the river for the next couple of hundred meters, and I'll start to make my own map, so I can plot it out from my notebook and overlay it on the original map, and that way I will have a more precise understanding of where our individual samples are coming from ....... {more re specifics of mapping). start moving down the section, see how the rocks change and seeing whether any of the other beds in the sequence have more and better preserved fossils. (5:45)
FX -5:46 -more walking through rocks and hammering............... TC: .................the coarseness of these sands and the inter-bedded nature of these conglomerates tells us that we're in an environment lying very closely offshore from a volcanic arc...........walking on....back into sands again..................walk about 40 yards to next bed that will underly these..........
FX -walking -TC and JJ off mic
FX 11:16 -Walking, Indians talking......
**JJ: There's little bits of curly shell allover in it. **TC: Do you think it's worth getting a micro?
Oh that's quite a bit finer..... ***Oh it's got plankton in it. The planktic foraminifera, these are the ones that when they were alive floated near the surface, and they are the ones that are the most useful for telling the age of the rocks.... so this is a very encouraging sign that we've got the planktic foraminifera. It means we have a very good possibility of dating this particular spot here....Usually the people who work with these fossils need about a 100 grams of sediment in a bag and from that 100 grams they can wash out hundreds -maybe thousands of specimens .... and that's more than enough to identify the different species that give you the age of the rock. 12:48
TC: Let's start off with CJ -9560 .....
TC: Alex: This is very encouraging sign, because Jeremy has pulled out a much finer grained piece of sediment and as I look over it I can see these globular planktic foraminifera that are the ones very useful for dating.... You put the lens close to your eye and you can see some little chambered organisms, they're like little globes stuck together. When they've broken this down...will get hundreds of specimens. If you can actually see planktic foraminifera in the hand lens in the field, it means there are going to be hundreds of them in the rock when they process it. It's encouraging because we're going to be able to date the rock, but doesn't necessarily mean Jeremy will find what he wants ....but if he does, he'll know how old it is. (15:03)
15:39 -FX Hammering
JJ: This is important for the dating
TC: Which is why you just can't go walking down the river looking for the fancy shells....Oh,there's a penshell, that is a pinner. You have to do the grunge work on just dirty looking rocks like this to get the sequence and the dates that you need to orient yourself in space and then you hope that at some frequency you find these very diverse faunas.
JJ: ........... .
AC: Now this isn't old......
TC: yes....it's almost certainly 7 million years....
AC: That little piece of shell that I'm holding in my hand....
TC: That perfect piece of mother of pearl is comfortably preserved for 7 million years, because we've gotten into much tighter, finer-grained sediment, and that essentially locks everything into a closed chemical system....and don't get leaching, weathering, alteration.....
JJ: ....they're very fragile, so to take them out whole is a labor of love. [17:44]

SS: 15:39 -17:44
17:44-ff JJ and TC; examining more sediment plus good chipping abbreviated logs: a "dip" is described; first step is to orient these in space; then Tony's role; geological hammer = pick; this is 15 over 250 degrees; inclined at 15 degrees... then I put this on the map -dip measurements; how rocks are conformed, then can reconstruct the stratigraphy = the sequence of beds; TC and JJ talking in Spanish re. Biff

00:25:36-31:00 FX -Walking through the river

00:37:30 -00:42:00 -scientists digging
[AC says Tony, can you briefly say what you like about this site?]
00:42:00 -00:43:53 -Well, we've worked our way downstream to the next exposure.....what's interesting about this exposure compared to the previous one is that the previous one was rich in the planktic foraminifera; those are the ones are the former plankton and float in the upper layers of the sea...they're the ones that are extremely valuable for time measurement. What we have in this exposure is a wide variety of the same kind of animal that lived in the bottom of the ocean in the mud; and while they're not nearly as useful for telling time, they're very sensitive to the conditions that exist at the bottom of the sea.....Laurie Collins, specialist on benthic (bottom) of the sea.....in my handlens, can see many diffferent species of sub-microscopic, benthic animals that will tell us about conditions at which these sediments were formed ....what depth, what kind of water energy ....like to get both because one gives you biological information....and the other chronological info.... [43:53]
44:20 -47:34 --JJ: Absolutely full of foraminifera (off mic); as abundant as I have ever seen them...... look at this....think that will do...fabulous; pointing out to Alex; Oh, tony, look at This: TC: maybe you want to have a look at it, Alex; have a look at this through your lens; and everyone of the tiny white dots.....AC: coooh, look at that, yeah; it's a coiled up shell, those are by the myriad; TC: This is absolutely loaded; I've rarely seen a rock that is more foraminiferal; every single fleck on that rock is a planktic foraminfera; we're quite grateful if see one....
47:37 (end with hammering)
48:50 -50:10 FX River Water
53:00 -54:00 FX Quiet Ambi -Birds, hammering, river

56:17 END

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