water, gas, and phylogenetic analyses from sulfur springs in cueva de villa luz, tabasco, mexico...
TRANSCRIPT
Water, Gas, and Phylogenetic Analyses from Sulfur Springs in
Cueva de Villa Luz, Tabasco, Mexico
Michael N. Spilde, Tobias P. Fischer, and Diana E. NorthupUniversity of New Mexico, Albuquerque, NM
H.J. TurinLos Alamos National Laboratory, Los Alamos, NM
Penelope J. BostonNew Mexico Inst. of Mining and Technology, Socorro, NM
Villahermosa
Cueva de Villa Luz
El Chichon
Photos by Kenneth Ingham © 2004 Kenneth Ingham
Elemental sulfur on ceilingElemental sulfur on ceilingSnottites
Phlegm balls
© 2004 Kenneth Ingham
© 2004 Kenneth Ingham
Phlegm balls in hydrogen sulfide springsPhlegm balls in hydrogen sulfide springs
Nearest Relative Clone # Similarity
Lower Kane Cave Epsilonproteobacteria C4,C6,D10,D12 94.4-98.7%
Hydrothermal vent Endosymbionts D1 92.4-92.6%
Unclass Bacterioidetes Hydrothermal Vent Symbiont/SRB
C7 78.0%
© 2004 Miichael Spilde
Sulfur IsotopesH2S Hose et al. 2000 -11.7‰
So “ -23.7‰
Gypsum “ -23.5 ‰H2S (El Chichón) Taran et al. 1998 +4.6 ‰
So (El Chichón) “ +4.5 ‰ Photo by Kenneth Ingham Photo by Kenneth Ingham © 2004 Kenneth Ingham© 2004 Kenneth Ingham
Sulfur Spring in Cueva de Villa Luz
Photos by Kenneth Ingham © 2004 Kenneth
Ingham
Perched Pool
ORP(mV) -250 -222 -216
pH 7.01 7.13 7.4
ORP(mV) -250 -222 -216
pH 7.01 7.13 7.4
-193 -193 -117 -117 –82–82 7.7 7.7 7.63 7.63 7.777.77-193 -193 -117 -117 –82–82 7.7 7.7 7.63 7.63 7.777.77
Oxidation-Reduction Potential Measurements
© 2004 Kenneth Ingham
Research Question:• What is the source of the hydrogen sulfide gas?
• H2S from Campeche oil and gas fields
• Magmatic gas from El Chichon
• Sulfate reduction in Campeche platform evaporites
Map by Jim Pisarowicz & Louise Hose© 1999 National Spleleological Society
Main Entrance
MidwaySprings
SulfurSpring
Perched Pool BoulderSpring
ResurgenceCueva de Villa Luz, Tabasco, Mexico
0 30
PhlegmaPhlegmaSpringSpring
26 groundwater inlets: 200-300 l/s
Sampled spring: waterSampled spring: gasSpring
Villa Luz Gas Chemistry
El Chichon & Agua Caliente data from Taran et al. 1998
• Not atmospheric gas
© 2004 Miichael Spilde
Villa Luz Gas Chemistry
El Chichon & Agua Caliente data from Taran et al. 1998
• Not atmospheric gas• Not thermogenic (not
derived from heating of sediments by intrusive bodies)
© 2004 Miichael Spilde
Villa Luz Gas Chemistry
El Chichon & Agua Caliente data from Taran et al. 1998
• From He isotopes, calculated magmatic component = 22%
© 2004 Miichael Spilde
Villa Luz Gas Chemistry
El Chichon & Agua Caliente data from Taran et al. 1998
• From He isotopes, calculated magmatic component = 22%
• Gas derived from mixing of mantle and crustal sources
© 2004 Miichael Spilde
Perched Pool
MidwaySprings
BoulderSpring
SulfurSpring
AguaCaliente
(El Chichonspring)
El Chichon Crater
Water Sampling
X10
Water samples:• 4 springs sampled in cave
•2 with low/no H2S gas•2 exhaling H2S
• Compared to El Chichon crater & spring (from Taran et al. 1998)
© 2004 Miichael Spilde
Perched Pool
MidwaySprings
BoulderSpring
SulfurSpring
AguaCaliente
(El Chichonspring)
El Chichon Crater
Water Sampling
X10
Water samples:• 4 springs sampled in cave
•2 with low/no H2S gas•2 exhaling H2S
• Compared to El Chichon crater & spring (from Taran et al. 1998)
© 2004 Miichael Spilde
Perched Pool
MidwaySprings
BoulderSpring
SulfurSpring
AguaCaliente
(El Chichonspring)
El Chichon Crater
Water Sampling
X10
Water samples:• 4 springs sampled in cave
•2 with low/no H2S gas•2 exhaling H2S
• Compared to El Chichon crater & spring (from Taran et al. 1998)
Results:• Little variation between
cave springs• SO4 & Cl nearly equal in
cave water• Low HCO3
• El Chichon water saline, dominated by Cl, low SO4
© 2004 Miichael Spilde
Villa Luz Water Chemistry
Met
eoric
Wat
er L
ine
Li
B• Trace elements elevated in Villa Luz
water
•B & Li high
•Hg about 10x EPS standard
* data from Taran et al. 1998
Villa Luz
El Chichon*
Agua Caliente*
Cold Spring*
Rainwater*
Mixing?
© 2004 Miichael Spilde
Villa Luz Water Chemistry
Met
eoric
Wat
er L
ine
Li
B• Trace elements elevated in Villa Luz
• Fall slightly off meteoric water line
* data from Taran et al. 1998
Villa Luz
El Chichon*
Agua Caliente*
Cold Spring*
Rainwater*
Mixing?
© 2004 Miichael Spilde
Villa Luz Water Chemistry
Met
eoric
Wat
er L
ine
Li
B• Trace elements elevated in Villa Luz
• Fall slightly off meteoric water line
• Suggests mixing of magmatic and
meteoric water
•Using Cl, we calculate 6% mix
* data from Taran et al. 1998
Villa Luz
El Chichon*
Agua Caliente*
Cold Spring*
Rainwater*
Mixing?
© 2004 Miichael Spilde
Villa Luz Water Modeling
PHREEQC Program (USGS) used to calculate mixtures of solutions.
Scenario 1: Simple dilution.Mix meteoric & magmaticEquilibrate with calcite.
© 2004 Miichael Spilde
Villa Luz Water Modeling
PHREEQC Program (USGS) used to calculate mixtures of solutions.
Scenario 1: Simple dilution.Mix meteoric & magmaticEquilibrate with calcite.
Scenario 2: Mixture of equilibrated fluids.
Equil. magmatic w/ CaSO4
Mix with meteoricEquilibrate with calcite.
© 2004 Miichael Spilde
Schematic Model of Water & Gas Sources at Cueva de Villa Luz
Eq CaS
O 4
Eq CaCO3
34S=+4.6
34S=-11.7
MW=4000 mm/yr
faul
t
D
SR
Gas
Water
Degassing
Sulfate reduction
SR
D
10 km
2 km
W E
© 2004 Miichael Spilde
Gases are predominately crustal gases
• No atmospheric signature
• Slight amount of CH4 not thermogenic
• Approximately 22% magmatic gases, based on He isotopes
• Water is predominantly meteoric
• Slightly elevated trace elements indicative of hydrothermal water
• Around 6% hydrothermal water mixed with meteoric
• SO4 in water derived from middle Cretaceous evaporites underlying cave
• H2S probably derived from bacterial sulfate reduction fueled by CH4
• BSR can occur in water column anywhere below the cave
Conclusions
© 2004 Miichael Spilde
Water modeling assistance from Laura Crossey, UNM
Gas analysis by Tobias Fischer, UNM
Water analyses by Jake Turin, LANL
Phylogenetic analysis by Diana Northup, UNM
Gas sampling by Doug Soroka & Penny Boston
Photographs by Kenneth Ingham, Albuquerque, NM
Partial funding from National Geographic Society to
Penny Boston & Louse Hose
Acknowledgements