1
00:00:12,090 --> 00:00:09,360
hi everyone my name is Johan Fong I'm a

2
00:00:14,190 --> 00:00:12,100
first-year med student in Geoscience

3
00:00:16,650 --> 00:00:14,200
department of university of wisconsin

4
00:00:19,380 --> 00:00:16,660
and today i'm gonna talk about more than

5
00:00:23,010 --> 00:00:19,390
damai from a needle a great playing and

6
00:00:25,470 --> 00:00:23,020
its implications so first of all why do

7
00:00:28,050 --> 00:00:25,480
i understudied oh my because dalam is a

8
00:00:30,870 --> 00:00:28,060
major component of the carbon named

9
00:00:32,819 --> 00:00:30,880
reservoir and also because dolomite is

10
00:00:35,790 --> 00:00:32,829
kind of weird you find tons of them in

11
00:00:39,930 --> 00:00:35,800
the Asian record but it's kind of rare

12
00:00:41,970 --> 00:00:39,940
in the morning setting out and there's a

13
00:00:44,670 --> 00:00:41,980
famous tola my problem because it's

14
00:00:48,240 --> 00:00:44,680
hardest emphasizing labs on their

15
00:00:51,240 --> 00:00:48,250
surface condition and one group tried to

16
00:00:54,720 --> 00:00:51,250
synthesize damai under using

17
00:00:57,960 --> 00:00:54,730
supersaturated solution with within 32

18
00:00:59,370 --> 00:00:57,970
years and they failed and some people

19
00:01:02,700 --> 00:00:59,380
provoke think that all of my information

20
00:01:07,139 --> 00:01:02,710
is largely related to the pile microbial

21
00:01:10,410 --> 00:01:07,149
activity so we think that might be true

22
00:01:13,170 --> 00:01:10,420
and first of all I want to show you guys

23
00:01:18,180 --> 00:01:13,180
Wallace dolomite so you have calcite

24
00:01:20,219 --> 00:01:18,190
here so is caco3 very simple and then if

25
00:01:22,260 --> 00:01:20,229
you replace have the calcium with

26
00:01:24,990 --> 00:01:22,270
magnesium and then they become older you

27
00:01:27,060 --> 00:01:25,000
got this ordered over mine and then so

28
00:01:29,130 --> 00:01:27,070
you got one layer of calcium that's the

29
00:01:31,740 --> 00:01:29,140
blue one and you got one layer of the

30
00:01:33,600 --> 00:01:31,750
magnesium that's a yellow one and if you

31
00:01:35,580 --> 00:01:33,610
just get out of my sometimes they're

32
00:01:37,320 --> 00:01:35,590
disorder and if they're like fifty

33
00:01:40,500 --> 00:01:37,330
percent magnesium in the crystal lattice

34
00:01:43,380 --> 00:01:40,510
then you have they would be random into

35
00:01:45,149 --> 00:01:43,390
circular so like this atom have fifty

36
00:01:49,530 --> 00:01:45,159
percent chance to be calcium nor fifty

37
00:01:53,429 --> 00:01:49,540
percent chance to be magnesium so how

38
00:01:56,609 --> 00:01:53,439
did it form our lab our research group

39
00:01:58,880 --> 00:01:56,619
try to synthesize over my lap so because

40
00:02:01,219 --> 00:01:58,890
we think is really to microbial activity

41
00:02:03,330 --> 00:02:01,229
first of all they try to use

42
00:02:05,030 --> 00:02:03,340
polysaccharides so sugar try to

43
00:02:07,590 --> 00:02:05,040
sympathize don't mind the lab and

44
00:02:09,779 --> 00:02:07,600
because the hard part for don't my to

45
00:02:11,729 --> 00:02:09,789
form is because the magnesium will bound

46
00:02:15,890 --> 00:02:11,739
with the water and so hard to get into

47
00:02:18,569 --> 00:02:15,900
the crystal lattice and they think

48
00:02:19,350 --> 00:02:18,579
polysaccharide can help to weaken the

49
00:02:21,990 --> 00:02:19,360
bounce between

50
00:02:23,790 --> 00:02:22,000
water and magnesium and then they

51
00:02:26,430 --> 00:02:23,800
successfully synthesized all of my

52
00:02:30,750 --> 00:02:26,440
disorder to a life you can't see in that

53
00:02:33,270 --> 00:02:30,760
deck tardy didn't hear this and so

54
00:02:36,510 --> 00:02:33,280
polysaccharide works well L what's the

55
00:02:39,480 --> 00:02:36,520
next step then so they use eps so

56
00:02:43,260 --> 00:02:39,490
polysaccharide is a major component of

57
00:02:46,110 --> 00:02:43,270
the EPS and they also Susilo synthesized

58
00:02:48,890 --> 00:02:46,120
all of my using eps adding to the

59
00:02:52,920 --> 00:02:48,900
solution in reasonably short time and

60
00:02:55,980 --> 00:02:52,930
but how is it exactly work so one of our

61
00:03:00,210 --> 00:02:55,990
peers student tried to use molecular

62
00:03:02,210 --> 00:03:00,220
dynamics to simulate the try manos

63
00:03:07,260 --> 00:03:02,220
that's the only one we work on right now

64
00:03:10,260 --> 00:03:07,270
to try to run the modeling on how much

65
00:03:12,750 --> 00:03:10,270
the sugar help the to weaken the bond

66
00:03:15,870 --> 00:03:12,760
between water and magnesium and it turns

67
00:03:17,670 --> 00:03:15,880
out that a lower the funding energy user

68
00:03:20,670 --> 00:03:17,680
like about point seven two point eight

69
00:03:23,910 --> 00:03:20,680
kilo child promote that's pretty sick so

70
00:03:26,580 --> 00:03:23,920
it turns out that like sugar is really

71
00:03:29,430 --> 00:03:26,590
helping the main easy to get into the

72
00:03:33,840 --> 00:03:29,440
crystal lattice to form don't mine so

73
00:03:36,180 --> 00:03:33,850
now we move to my study so I was working

74
00:03:39,390 --> 00:03:36,190
on natural sample so where can you find

75
00:03:41,550 --> 00:03:39,400
more than total mind L don't mind mostly

76
00:03:44,580 --> 00:03:41,560
finds from LA right now and they're

77
00:03:46,259 --> 00:03:44,590
mostly in tropic setting I don't talk we

78
00:03:49,080 --> 00:03:46,269
heard this morning they're from like a

79
00:03:51,090 --> 00:03:49,090
Bahamas those area marine setting really

80
00:03:54,750 --> 00:03:51,100
warm temperature this one's the mini

81
00:03:56,699 --> 00:03:54,760
lake is in Saskatchewan Canada is really

82
00:03:59,729 --> 00:03:56,709
in a really co setting is even colder

83
00:04:03,330 --> 00:03:59,739
than medicine and the water level drops

84
00:04:06,210 --> 00:04:03,340
significantly from 1911 to now so you

85
00:04:09,300 --> 00:04:06,220
can see the block the light blue is the

86
00:04:12,449 --> 00:04:09,310
original size of the lake and it dropped

87
00:04:16,110 --> 00:04:12,459
to only about this much no and because

88
00:04:19,140 --> 00:04:16,120
the water is a they evaporate a lot of

89
00:04:22,770 --> 00:04:19,150
water the pH increase from 9.3 to close

90
00:04:26,700 --> 00:04:22,780
to 10 now and also the magnesium content

91
00:04:30,870 --> 00:04:26,710
in the lake also increase so this is

92
00:04:32,730 --> 00:04:30,880
what the future looks like surprisingly

93
00:04:33,239 --> 00:04:32,740
we found most of the carbonates are in

94
00:04:35,069 --> 00:04:33,249
the form

95
00:04:38,609 --> 00:04:35,079
of Cody bouldery rather than the stroma

96
00:04:41,189 --> 00:04:38,619
you expect to see and there most of them

97
00:04:43,949 --> 00:04:41,199
are found in like a really may fake

98
00:04:47,489 --> 00:04:43,959
rocks and even in the same location some

99
00:04:49,889 --> 00:04:47,499
are felsic rather than have any color

100
00:04:52,529 --> 00:04:49,899
border to company growing on top of them

101
00:04:54,719 --> 00:04:52,539
and only on the east side of the lake we

102
00:04:57,299 --> 00:04:54,729
found this pinnacle extra man like

103
00:04:59,189 --> 00:04:57,309
growing and then if you cut it open the

104
00:05:02,099 --> 00:04:59,199
middle is really black and it's loose

105
00:05:03,779 --> 00:05:02,109
and it smells that probably indicates it

106
00:05:06,419 --> 00:05:03,789
has tons of getting material inside of

107
00:05:10,049 --> 00:05:06,429
it and then this is the hand sample you

108
00:05:12,109 --> 00:05:10,059
can see the outer outside like with

109
00:05:15,929 --> 00:05:12,119
respect to see in a stromatolite is

110
00:05:18,029 --> 00:05:15,939
porous and the rock is very young from

111
00:05:21,359 --> 00:05:18,039
previous study this show that late

112
00:05:27,119 --> 00:05:21,369
holocene so maybe less than 500 years

113
00:05:29,429 --> 00:05:27,129
old and so this is the optical images

114
00:05:31,409 --> 00:05:29,439
you can see more clearly now there is a

115
00:05:33,449 --> 00:05:31,419
really bright layer and there's a dark

116
00:05:36,139 --> 00:05:33,459
layer and then we think the dark layers

117
00:05:39,989 --> 00:05:36,149
are any bridge in the organic material

118
00:05:42,419 --> 00:05:39,999
but how we gonna test that uh-huh what

119
00:05:46,709 --> 00:05:42,429
if there is no my inside of it so we use

120
00:05:49,109 --> 00:05:46,719
x-ray diffraction xrd ah so you have the

121
00:05:50,999 --> 00:05:49,119
x-ray source here and the heat sample

122
00:05:53,069 --> 00:05:51,009
and then scatter based on practice law

123
00:05:56,219 --> 00:05:53,079
in different angle and then we collect

124
00:05:57,659 --> 00:05:56,229
that in the detector for a 2d

125
00:05:59,879 --> 00:05:57,669
diffraction pattern and view software to

126
00:06:02,639 --> 00:05:59,889
convert back to what D so it's easier to

127
00:06:06,329 --> 00:06:02,649
analyze so because this machine can do

128
00:06:09,479 --> 00:06:06,339
institute xrd so we can actually pick

129
00:06:13,079 --> 00:06:09,489
individual points from the rock and then

130
00:06:17,639 --> 00:06:13,089
examine the minerals inside of it so we

131
00:06:22,579 --> 00:06:17,649
can see one two and five is like this

132
00:06:26,699 --> 00:06:22,589
and it has tons of oregano calcite and

133
00:06:29,249 --> 00:06:26,709
though my pecan bit but in the dark area

134
00:06:31,559 --> 00:06:29,259
the free and for all you can see was

135
00:06:34,379 --> 00:06:31,569
just on my you can find a rag night and

136
00:06:37,769 --> 00:06:34,389
calcite it probably some high magnesium

137
00:06:40,859 --> 00:06:37,779
chance at but mostly total mine and take

138
00:06:43,679 --> 00:06:40,869
a closer look at the dolomite here this

139
00:06:46,199 --> 00:06:43,689
is the dolomite we got from the lake and

140
00:06:46,950 --> 00:06:46,209
this is a standard over my x-ray

141
00:06:50,040 --> 00:06:46,960
diffraction

142
00:06:53,219 --> 00:06:50,050
and you can see that we is missing a pig

143
00:06:55,860 --> 00:06:53,229
here that's the 015 pic that's depict

144
00:06:57,689 --> 00:06:55,870
indicating the ordinance of the goal of

145
00:07:01,409 --> 00:06:57,699
mine so that helps us our dough in my

146
00:07:04,050 --> 00:07:01,419
history young and is really disorder but

147
00:07:06,689 --> 00:07:04,060
xrd cannot tell how much disorder that

148
00:07:11,760 --> 00:07:06,699
oh my is that she is so we need leave it

149
00:07:18,990 --> 00:07:11,770
yeah for that and then this is the fee

150
00:07:21,990 --> 00:07:19,000
104 and magnesium percentage so we think

151
00:07:23,850 --> 00:07:22,000
previous think that are you can use the

152
00:07:27,510 --> 00:07:23,860
composition to tell the tale spacing of

153
00:07:29,640 --> 00:07:27,520
them all right but this is the complete

154
00:07:32,700 --> 00:07:29,650
orders olamide this is the complete

155
00:07:35,999 --> 00:07:32,710
disorder tore my our sample falls into

156
00:07:39,180 --> 00:07:36,009
this little red circle around here so

157
00:07:41,189 --> 00:07:39,190
now not just a conversation are

158
00:07:45,240 --> 00:07:41,199
controlling the size of the crystal

159
00:07:47,040 --> 00:07:45,250
lattice is also be the ordinance is also

160
00:07:50,550 --> 00:07:47,050
controlling that so we were thinking

161
00:07:53,040 --> 00:07:50,560
about running Ward keeps ah experiment

162
00:08:00,600 --> 00:07:53,050
to find out where they said leave this

163
00:08:03,689 --> 00:08:00,610
line with falls on and then so it turns

164
00:08:05,760 --> 00:08:03,699
out though might because only the really

165
00:08:07,830 --> 00:08:05,770
organic rich part of the rock dust

166
00:08:10,920 --> 00:08:07,840
Ramallah I we found all my constraint in

167
00:08:12,749 --> 00:08:10,930
them so we think on my distribution are

168
00:08:15,719 --> 00:08:12,759
controlled by the organic material

169
00:08:18,290 --> 00:08:15,729
distribution and they're also don't my

170
00:08:21,390 --> 00:08:18,300
might be able to use the indicator for

171
00:08:24,029 --> 00:08:21,400
microorganism so that if you ever find

172
00:08:26,730 --> 00:08:24,039
out doe my on Mars for example there

173
00:08:29,310 --> 00:08:26,740
might be probably from a fair chance to

174
00:08:31,290 --> 00:08:29,320
say that it's a biogenic and then it

175
00:08:33,959 --> 00:08:31,300
might indicate there's microorganism

176
00:08:36,719 --> 00:08:33,969
once living on Mars and then for the

177
00:08:40,649 --> 00:08:36,729
next that we're thinking about using gas

178
00:08:43,290 --> 00:08:40,659
chromatog in a stronger GCMs for organic

179
00:08:46,410 --> 00:08:43,300
content so we get a better quantitive

180
00:08:49,550 --> 00:08:46,420
relation between the X double my

181
00:08:53,310 --> 00:08:49,560
percentage and organic materials and

182
00:08:57,689 --> 00:08:53,320
then also using more xrd to get more

183
00:09:00,390 --> 00:08:57,699
data points for the dolomite and then

184
00:09:02,910 --> 00:09:00,400
also using scanning electron microscope

185
00:09:05,940 --> 00:09:02,920
cm to get a me fall detail mythology up

186
00:09:08,820 --> 00:09:05,950
the rock for the minerals and then using

187
00:09:11,070 --> 00:09:08,830
epma the electron probe microanalysis to

188
00:09:14,940 --> 00:09:11,080
get exact composition because xrq can

189
00:09:19,890 --> 00:09:14,950
now provide you with a really ah really

190
00:09:22,500 --> 00:09:19,900
good reliable also we're because the 015

191
00:09:24,840 --> 00:09:22,510
pick is really really low we cannot tell

192
00:09:27,060 --> 00:09:24,850
you're just using SRD and the refinement

193
00:09:30,990 --> 00:09:27,070
so we need to use transmission electron

194
00:09:33,870 --> 00:09:31,000
microscope to get the exactly was the

195
00:09:36,780 --> 00:09:33,880
ordinance of the dolomite so we can have

196
00:09:39,600 --> 00:09:36,790
more correlation between them and also

197
00:09:42,380 --> 00:09:39,610
because TN has ed as attached to it so

198
00:09:45,630 --> 00:09:42,390
we can use in ds2 get a much better

199
00:10:07,509 --> 00:09:45,640
accurate composition information through

200
00:10:11,630 --> 00:10:10,670
yeah I have a kind of a weird one good

201
00:10:14,449 --> 00:10:11,640
talk by the way that was a lot was

202
00:10:16,190 --> 00:10:14,459
awesome some years ago and one of my

203
00:10:19,370 --> 00:10:16,200
cultures of software reducing

204
00:10:21,769 --> 00:10:19,380
microorganisms I saw these really weird

205
00:10:23,060 --> 00:10:21,779
structures that I've never gone down the

206
00:10:26,019 --> 00:10:23,070
path of trying to figure out what they

207
00:10:29,210 --> 00:10:26,029
really are but I know that they're there

208
00:10:31,519 --> 00:10:29,220
magnesium and there's carbonate and

209
00:10:33,380 --> 00:10:31,529
there's calcium in these structures and

210
00:10:35,960 --> 00:10:33,390
they look like dumbbells little

211
00:10:38,210 --> 00:10:35,970
microbial dumbbells and I've seen in the

212
00:10:40,100 --> 00:10:38,220
literature that it's been claimed some

213
00:10:41,329 --> 00:10:40,110
years ago that when you see these things

214
00:10:43,970 --> 00:10:41,339
that they are actually dolemite being

215
00:10:45,949 --> 00:10:43,980
formed by microorganisms in the lab but

216
00:10:48,259 --> 00:10:45,959
I have what I have two small amount of

217
00:10:50,810 --> 00:10:48,269
material to really figure out with xrd

218
00:10:52,069 --> 00:10:50,820
that it's dolomite so what would you

219
00:10:53,360 --> 00:10:52,079
suggest you could do for something like

220
00:10:54,800 --> 00:10:53,370
that and do you think that even could be

221
00:10:55,940 --> 00:10:54,810
Donell my do you think that there's kind

222
00:10:57,500 --> 00:10:55,950
of papers where they suggest that

223
00:11:00,290 --> 00:10:57,510
microbes make these little dumbbell

224
00:11:01,639 --> 00:11:00,300
structures and unique forms that that

225
00:11:03,470 --> 00:11:01,649
would be dolemite yeah I'm not sure

226
00:11:05,960 --> 00:11:03,480
about it dumbbell structured but I think

227
00:11:09,230 --> 00:11:05,970
their lives are suggesting like South by

228
00:11:11,630 --> 00:11:09,240
reducing bacteria can promote rope don't

229
00:11:14,389 --> 00:11:11,640
mind if you have really small amount on

230
00:11:17,540 --> 00:11:14,399
my not enough for xrd probably you can

231
00:11:23,420 --> 00:11:17,550
use TM to determine that okay awesome

232
00:11:26,420 --> 00:11:23,430
hey cool um I was just a little confused

233
00:11:28,670 --> 00:11:26,430
about how with xrd you can only really

234
00:11:31,009 --> 00:11:28,680
look at crystal and mineral so confused

235
00:11:33,980 --> 00:11:31,019
how you were saying it was disordered

236
00:11:35,329 --> 00:11:33,990
but based on the absence of a peak but

237
00:11:37,250 --> 00:11:35,339
like why would it give you such a nice

238
00:11:40,400 --> 00:11:37,260
xrd pattern to begin with if it was that

239
00:11:42,939 --> 00:11:40,410
disordered oh because the space group

240
00:11:46,639 --> 00:11:42,949
for a causa and alumni are different so

241
00:11:49,130 --> 00:11:46,649
callous I was our free art bar 3c and

242
00:11:52,460 --> 00:11:49,140
then don't my was our part 3 so they're

243
00:11:54,350 --> 00:11:52,470
like slightly different because if you

244
00:11:56,509 --> 00:11:54,360
get a disorder dolomite then would be

245
00:11:59,120 --> 00:11:56,519
more closer to the calcite and they were

246
00:12:04,460 --> 00:11:59,130
missing one peak if you only get that

247
00:12:06,350 --> 00:12:04,470
pic if you ordered online so because

248
00:12:10,250 --> 00:12:06,360
once you have order dolomite you have

249
00:12:12,319 --> 00:12:10,260
one layer sorry if you could go back to

250
00:12:13,550 --> 00:12:12,329
that disordered slider be awesome

251
00:12:14,900 --> 00:12:13,560
because I guess I just wasn't really

252
00:12:16,120 --> 00:12:14,910
understanding what you meant by

253
00:12:18,970 --> 00:12:16,130
disordered in this console

254
00:12:21,310 --> 00:12:18,980
sent so if you get ordered all my you

255
00:12:27,940 --> 00:12:21,320
actually a wonder your calcium in one

256
00:12:30,610 --> 00:12:27,950
video ok distributed randomly ok handing

257
00:12:33,700 --> 00:12:30,620
on the ordinance of the UH of the

258
00:12:36,430 --> 00:12:33,710
crystal so if you have this you actually

259
00:12:42,310 --> 00:12:36,440
adding more information to it so thank

260
00:12:44,830 --> 00:12:42,320
you I just a quick comment like a

261
00:12:47,260 --> 00:12:44,840
student is asked question have fun is a

262
00:12:49,140 --> 00:12:47,270
weekend whatever can run exactly how

263
00:12:52,630 --> 00:12:49,150
could it because we can do micro x-ray

264
00:12:55,090 --> 00:12:52,640
diffraction no problem but I just let

265
00:12:57,580 --> 00:12:55,100
you know okay most published papers a

266
00:13:01,270 --> 00:12:57,590
cook or a microbial dolomite are not a

267
00:13:02,500 --> 00:13:01,280
dollar mad so most of them I phosphated

268
00:13:04,780 --> 00:13:02,510
because they put a fulfilling their

269
00:13:06,610 --> 00:13:04,790
fourth Vader and a magnesium calcium

270
00:13:09,280 --> 00:13:06,620
they love each other very much so

271
00:13:11,140 --> 00:13:09,290
they're from 1st to the precipitates so

272
00:13:13,270 --> 00:13:11,150
and even some people even people

273
00:13:17,070 --> 00:13:13,280
purposely destroyed to the data okay

274
00:13:20,770 --> 00:13:17,080
fabricated data to cream dollar mad and

275
00:13:23,620 --> 00:13:20,780
student took a my course okay they have

276
00:13:26,590 --> 00:13:23,630
a project to read the papers and I found

277
00:13:29,320 --> 00:13:26,600
out what's wrong with the epic papers so

278
00:13:33,490 --> 00:13:29,330
because dollar matters is so important

279
00:13:35,680 --> 00:13:33,500
okay it's a challenging problem so I and

280
00:13:38,130 --> 00:13:35,690
also very recently last month the other

281
00:13:41,950 --> 00:13:38,140
paper thing that you know of a sediment

282
00:13:46,210 --> 00:13:41,960
sedimentary research paper by Professor

283
00:13:49,240 --> 00:13:46,220
J and aqueous at all from Oklahoma State

284
00:13:53,620 --> 00:13:49,250
University so they they just hope tablet

285
00:13:55,930 --> 00:13:53,630
although the papers okay they they they

286
00:13:58,390 --> 00:13:55,940
are being the ability and automata

287
00:14:00,970 --> 00:13:58,400
little right but what are you know some

288
00:14:03,040 --> 00:14:00,980
of my students paper they Kremlin much

289
00:14:06,100 --> 00:14:03,050
is the dollar matter whatever real stuff

290
00:14:09,940 --> 00:14:06,110
in there so dumb bear down the mean like