Presented at the Norwegian Network on Impact Research workshop at Gol/Gardos, July 2-7, 2012.

1. The Boltysh crater fill sediments – a 500,000 year record of the
lower Danian
I. Gilmour1, D.W. Jolley2, R.J. Daly2, S.P. Kelley1, and M.A. Gilmour1
1. Department of Physical Sciences, The Open University, Milton Keynes MK7 6AA, UK
2. Department of Geology & Petroleum Geology, University of Aberdeen, Aberdeen AB9 2UE, UK

2. The Boltysh crater lacustrine sediments accumulated in around 600m of
accommodation space on the Ukrainian shield. The continuity of this
accommodation space post-impact would have ensured a continuous record of
deposition without the intervals of non-deposition inherent in fluvio-deltaic
depositional settings.

3. Boltysh Impact Crater
• 25km complex crater
• Ukrainian Shield – impact on
land
• Ar/Ar age 65.17 ± 0.64 Ma
(Kelley & Gurov, 2002)

4. Boltysh Impact Crater
• 25km complex crater
• Ukrainian Shield – impact on
land
• Ar/Ar age 65.17 ± 0.64 Ma
(Kelley & Gurov, 2002)
• Drilled in the 1960s & 70s
• Cores lost

5. Boltysh Impact Crater
• 25km complex crater
• Ukrainian Shield – impact on
land
• Ar/Ar age 65.17 ± 0.64 Ma
(Kelley & Gurov, 2002)
• Drilled in the 1960s & 70s
• Cores lost
• 500m crater-fill sediments central peak
Impact melt
Cross
sec(on
reconstructed
from
Russian
data

6. Boltysh Impact Crater
• 25km complex crater
• Ukrainian Shield – impact on
land
• Ar/Ar age 65.17 ± 0.64 Ma
(Kelley & Gurov, 2002)
• Drilled in the 1960s & 70s
• Cores lost
• 500m crater-fill sediments
• Paleogeography
n the North-Eastern Peri-Tethys during the Cretaceous
Baraboshkin
et
al.,
2003

9. Drilled ~12m impact breccia
at base of hole

11. • 596m
cored
borehole
west
of
central
upliA
• >95%
recovery
• 596
-­‐
582m
–
allochthonous
impact
breccia
• 390m
Cenzoic
crater
fill
• 582
–
490m
cyclic,
fining
upwards,
poorly
sorted
sands
and
sandy
muds
>
turbidity
currents
• 490
–
190m
finely
laminated
organic
rich
shales
• Lacustrine,
abundant
plant
macrofossils
• ~300m
abundant
ostracods
and
gastropods
(in
life
posi(on),
interbedded
with
gypsum
lamellae
>
shallow
evapora(ve
lake

12. Palynology Summary
• Palynomorphs – most
abundant fossil group
• Good preservation – no
thermal alteration/degradation
• Dominated by pollen and
spores but include algae
• Early Danian throughout
– Consistent with Cavagnetto and
Gaudant (2000) based on IGCP
pollen stratigraphic scheme of
Meyer (1980)
• Highly diverse palynoflora
– crater marginal
– regional vegetation
Ferns
Swamp
cypresses
Normapolles

13. Relationship between the Boltysh and Chicxulub Impacts
• Palynological Succession
– Replacement of one floral
community with another in a given
area
• Supported by δ13CTOC record
• Recovery successions
– Well documented (volcanic)
– K-Pg from Western Interior (US)
• “Fern spike” – an influx of fern spores in
post K-Pg sediments
• Phase 1 – warm temperate, subhumid,
broadleaved evergreeen
• Phase 2 – leaf, rhizome and cuticles of
ferns
• Phase 3 – early successional, high ppt
• Phase 4 – warm temperate, moderately
diverse

14. Location of K/Pg Boundary
Jolley,
D.W.,
Gilmour,
I.,
Gurov,
E.P.,
Kelley,
S.P.,
Watson,
J.,
2010.
Geology
38,
835–838.

15. Hopane
in
sediment
(biological
configura(on)
Hopane
in
sediment
(geological
configura(on)
ββ22R
βα22R
αβ22R
αβ22S
x

16. ββ
ββ
+
αβ
+
βα
Energy
Reac(on
progress
AAer
Seifert
and
Moldowan,
1980)
ββ
βα
αβ
ΔG2
ΔG3
ΔG1
ΔG4
Thermal
maturity

17. 8.5m
No
ββ
present
ββ
biological
7.1m
ββ
transi(on

18. Modelling cooling of impact hydrothermal systems
Figure 3. Results of a numerical simulation of the hydrothermal system at a 30-km crater on early
Mars. The central peak of the crater is on the left side of each figure. Surface permeability k0 is 10À2
darcies.
Solid arrows and dotted arrows indicate the water and steam fluxes, respectively. The lack of arrows in some
regions indicates that fluxes are less than 2 orders of magnitude smaller than the maximum flux. Solid lines
are isotherms, labeled in degrees Celsius. The length of the arrows scales logarithmically with the flux
magnitude, and the maximum value changes with each plot. (a) 25 years, max. water flux = 6.66 Â
E12S09 ABRAMOV AND KRING: HYDROTHERMAL ACTIVITY ON EARLY MARS E12S09
Abramov
&
Kring,
2005)

19. 8.5m
No
ββ
present
ββ
biological
7.1m
ββ
transi(on
ca.
20ka

20. Jolley,
D.W.,
Gilmour,
I.,
Gurov,
E.P.,
Kelley,
S.P.,
Watson,
J.,
2010.
Geology
38,
835–838.
<20ka

21. Boltysh
• Pre-dates Chicxulub impact
– Establishment of an early successional flora post
Boltysh impact implies 5-10ka pre-Chicxulub
• Cooling hydrothermal system
– Timescale for post-Boltysh and Post-Chicxulub
recovery
• Rest of core
– 550 C-isotope measurements
– Early Danian climate change

22. Carbon Isotopes
• algal/higher plant input
• Significant CIE 537 – 271m
• Lacustrine δ13Corg
• Selective preservation
• Maturation
• Allochthonous inputs
• Boltysh OM
• Immature sapropellic kerogen
• %C not correlated with δ13Corg
• Reliable indicator of C cycle change
K
Pg
-38 -36 -34 -32 -30 -28 -26 -24 -22 -20
δ13Corg (‰)
Δδ13C
~
-­‐3‰
Δδ13C
~
+4‰
Posi(ve
excursion

23. -38 -36 -34 -32 -30 -28 -26 -24 -22 -20
δ13Corg (‰)

24. Dan-C2 CIE
! Atlantic (Quillévéré et al. (2008)
– Benthic δ13C
– 2 excursions
! Tethys (Coccioni et al. (2010)
– Similar to Atlantic
X Pacific (Westerhold et al. 2011)
– No record at Shatsky Rise
– Restricted to Atlantic?
! Continental
– Boltysh lacustrine record
– Global CIE
Quillévéré
et
al.
(2008)
Fig. 2. Changes in δ13
C and δ18
O of bulk sediments, CaCO3 content, and magnetic susceptibility (χ) in the lowermost Danian at Contessa Highway, plotted with changes in δ13
C and δ18
O of bulk sediments, CaCO3 content, and magnetic
susceptibility from the equivalent stratigraphic interval at ODP Hole 1049C (Black Nose, NW Atlantic) and DSDP Holes 527 and 528 (Walvis Ridge, SE Atlantic), where the Dan-C2 event was first recognized by Quillévéré et al. (2008). Reliable
300R.Coccionietal./EarthandPlanetaryScienceLetters297(2010)298–3
Coccioni
et
al.
2010

25. Comparison with Toarcian and PETM CIEs
In contrast to the marine Dan-C2 records, the Boltysh record more closely
resembles other major CIEs – Isotope stages after Cohen et al. (2007)

26. CIE Mass Balance
McInerney & Wing (2011)

27. regional and even global ecosystems. A rapid larly forced, end Maastrichtian extinctions across the
Fig. 1. Present-day Deccan Trap outcrop extent. Major tectonic structures redrawn from Biswas (1991).
Main Deccan Province – from Cripps et al. (2005)
• Final
stages
of
Deccan
–
interac(on
of
basal(c
lavas
and
dykes
with
con(nental
shelf
sediments
• Evidence
of
interac(on
in
the
Mumbai
area
organic-­‐rich
shales
occur
as
intertrappean
sequences
• δ13Corg
~
-­‐26‰
• Produc(on
of
thermogenic
CH4
from
sedimentary
organic
• isotopic
frac(ona(on
=
-­‐1.4‰
and
-­‐17.5‰
(Clayton
et
al.
1991)

28. in the
vitrinit
intrusi
and M
accura
tures
900 °C
An
is that
into ho
as long
ganic m
sins w
emplac
(13) sh
geothe
thickn
and Cesare (1993) contoured for pressures ranging from 100 to 500 MPa. For
methane at $375 °C, while fluids in rocks of 5 wt.% TOC are miscible at $2
Calculated densities of the fluid(s) at 100 MPa. At this pressure the CH4-domina
while the H2O-dominated phase will have a relatively much higher density of $9
totalKarooBasin
westernKarooBasin
wt%TOC
Area intruded by 100 m thick sill [km2]
GenerationpotentialCH4[Gt]
35 000
30 000
25 000
20 000
15 000
10 000
5 000
50 000 250 000 350 000150 000
10
9
8
7
6
5
4
3
2
1
VøringandMøreBasins
Fig. 9. Calculated total methane potential in gigatons, (Gt) as a
function of area covered by a cumulative intrusion thickness of
100 m continuous sill. The generation potentials are for the western
7017
Gt
150
000
km2
Thermogenic methane from contact metamorphism
(Aarnes et al., 2010)

30. Summary – Boltysh Crater fill sediments
• 24km diameter Boltysh Impact Crater in Ukraine
– Lacustrine crater fill sequence of fine grained organic carbon-rich sediments
– Preserve a uniquely complete and detailed negative carbon isotope excursion (CIE) in
an expanded section of several hundred metres.
• Position of CIE in the early Danian, ca. 200ka above K/Pg
– Correlates with Dan-C2 CIE in marine record
– Early Danian Hyperthermal Event
• Changes in floral communities through the CIE reflect changing biomes
caused by rapidly warming climate, followed by recovery
– EDH event had a similar duration to the Toarcian and Paleocene/Eocene events
• Temporal correlation EDH event with late stages of Deccan Continental
Flood basalt province, and initiation of rifting
– Deccan province: cause of global warming and the carbon-isotope excursion
• A high resolution record that is potentially resolving the effect of
Chicxulub from the effects of Deccan
• High resolution/stratigraphically complete records have implications…