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periodicities in the Middle and Late effects that try to explain long-wavelength Föllmi, K., 2012, Early Cretaceous life, climate and
Triassic (~5-m.y./cycle on average for third- and long-term tectonic warping (see, e.g., anoxia: Cretaceous Research, v. 35, p. 230–257,
https://doi.org/10.1016/j.cretres.2011.12.005.
order sequences) and no evidence of wide- Gurnis, 1993; Flament et al., 2013). On Glørstad-Clark, E., Faleide J-I., Lunschien, B. and
spread glaciation. However, the relatively these longer scales subducting slabs under- Nystuen, J., 2010, Triassic sequence stratigraphy
moderate variations in third-order sea lev- neath continents dramatically influence and paleogeography of the western Barents
els make it tempting to consider the surface topography that in turn could drive Sea: Marine and Petroleum Geology, v. 27,
possibility of changes driven by the transfer local eurybathic sea-level changes. Thus, p. 1448–1475, https://doi.org/10.1016/j.marpetgeo
of water to and from land aquifers as a dynamic topography-driven variations seem .2010.02.008.
potential cause. Since the early suggestion to be a promising avenue to follow to Gorter, J.D., 1994, Triassic sequence stratigraphy
of the Carnarvon Basin, Western Australia
by Hay and Leslie (1990) and Jacobs and explain the relatively small amplitude but in Purcell, P.G., and Purcell, R.R., eds., The
Sahagian (1993) there has been consider- long duration highs and lows (within the Sedimentary Basins of Western Australia:
able recent interest in this mechanism as a range of –50 m to +50 m of pdmsl) of the Perth, Proceedings of the Petroleum Exploration
potential cause for eustatic changes (e.g., long-term eustatic sea level in the Triassic. Society Australia Symposium p. 397–413.
Föllmi, 2012; Wagreich et al., 2014; So far such modeling for the Triassic super- Gurnis, M., 1993, Phanerozoic marine inundation
Wendler and Wendler, 2016; Sames et al., continent and its margins has not been of continents driven by dynamic topography
above subducting slabs: Nature, v. 364, p. 589–
2016). Nevertheless, this process is more attempted and is obviously an area of 593, https://doi.org/10.1038/364589a0.
attuned to explaining modest (20–30 m) important future investigation. Haas, J., and Budai, T., 1999, Triassic sequence
input/sequestration of water from/to land stratigraphy of the Transdanubian Range
groundwater aquifers (and to a much lesser ACKNOWLEDGMENTS (Hungary): Geologica Carpathica, v. 50, no. 6,
extent, the lakes that contribute only a The author is indebted to professors James Ogg, p. 459–475.
minute, almost unmeasurable, amount to William Hay, Jerry Dickens, and an anonymous Hallam, A., and Wignall, P.B., 1997, Mass
extinctions and their aftermath: New York,
the total) to the ocean on Milankovitch reviewer for detailed reviews of the paper and Oxford University Press, 330 p.
time scales (Hay and Leslie, 1990). In the many useful suggestions that improved the quality Haq, B.U., 2014, Cretaceous eustasy revisited:
of the paper. Christopher Scotese provided the
Triassic the process seems counterintuitive reconstructions on which Figure S1 is based. Global and Planetary Change, v. 113, p. 44–58,
as very dry periods on land coincide with Alexandre Lethier (Sorbonne, ISTEP) assiduously https://doi.org/10.1016/j.gloplacha.2013.12.007.
lowstands of sea level when presumably drafted the Triassic cycle chart presented in this Haq, B.U., 2017, Jurassic sea level variations: A
continental interiors would tend toward paper and the figures in the GSA data repository reappraisal: GSA Today, v. 28, no. 1, doi:10.1130/
GSATG359A.1.
depleted aquifers (and also lack large that accompanies the paper. Haq, B.U., and Al-Qahtani, A.M., 2005, Phanerozo-
lakes). The reverse also seems to be the REFERENCES CITED ic cycles of sea-level change on the Arabian
case; i.e., during the late Carnian Pluvial Platform: GeoArabia, v. 10, no. 2, p. 127–160.
Episode, when the climates were wetter and Aigner, T., and Bachmann, G., 1992, Sequence Haq, B.U., and Schutter, S.R., 2008, A chronology
stratigraphic framework of the German Triassic:
characterized by a single third-order event, Sedimentary Geology, v. 80, p. 115–135, https:// of Paleozoic sea-level changes: Science, v. 322,
p. 64–68, https://doi.org/10.1126/science.1161648.
the long-term sea level was also relatively doi.org/10.1016/0037-0738(92)90035-P. Haq, B.U., Hardenbol, J., and Vail, P.R., 1987,
higher. Thus, if the process has to work in Bhargava, O., Krystyn, L., Balini, M., Lein, R., and Chronology of fluctuating sea level since the
the Triassic, it would have to have been on Nicora, A., 2004, Revised Litho- and Sequence Triassic: Science, v. 235, p. 1156–1167, https://
the shorter, Milankovitch, time scales. Stratigraphy of the Spitin Triassic: Albertiana, doi.org/10.1126/science.235.4793.1156.
v. 30, p. 21–39.
What solid-Earth tectonic controls could Bourquin, S., Peron, S., and Durand, M., 2006, Haq, B.U., Hardenbol, J., and Vail, P.R., 1988,
have potentially influenced the sea-level Lower Triassic sequence stratigraphy of the Mesozoic and Cenozoic chronostratigraphy and
changes in the Triassic when the planet was western part of the Germanic Basin (west Black cycles of sea-level change: Society of Economic
Paleontologists and Mineralogists Special Publi-
characterized by a large supercontinent Forest): Fluvial system evolution through time cation, v. 42, p. 71–108.
with no apparent major ice accumulations and space: Sedimentary Geology, v. 186, p. 187– Hardenbol, J., Thierry, J., Farley, M.B., Jacquin,
211, https://doi.org/10.1016/j.sedgeo.2005.11.018.
on land? Most of the recent insights into the Budai, T., and Haas, J., 1997, Triassic sequence T., De Graciansky, P.C., and Vail, P.R., 1998,
understanding of tectonic influences on sea stratigraphy of the Balaton Highland, Hungary: Mesozoic and Cenozoic sequence chronostrati-
level (as measured locally) either try to Acta Geologica Hungarica, v. 40, no. 3, p. graphic framework of European basins: Society
explain it on very short time scales (isostatic 307–335. of Economic Paleontologists and Mineralogists
Special Publication 60, p. 3–13 (Chart 8, Triassic
response to elastic and viscous loading and Cloetingh, S., and Haq, B.U., 2015, Inherited Chronostratigraphy).
unloading) or on the very long time scales landscapes and sea level change: Science, v. Hay, W.W., and Leslie, M.A., 1990, Could possible
347, https://doi.org/10.1126/science.1258375.
of multiple millions of years (see discus- Davies, J.H., Marzoli, A., Bertrand, H., Youbi, N., changes in global groundwater reservoir cause
sions in Haq, 2014, 2017, and Cloetingh and Ernesto, M., and Schaltegger, U., 2017, End- eustatic sea level fluctuations?, in Geophysics
Haq, 2015). These influences cannot Triassic mass extinction started by intrusive Study Committee, Mathematics and Resources,
account for the third-order cyclicity in the CAMP activity: Nature Communications, National Research Council, eds., Sea Level
Change: Studies in Geophysics: Washington
https://doi.org/10.1038/ncomms15596.
Early and Middle Triassic (average duration Embry, A.F., 1997, Global sequence boundaries D.C., National Academy Press, p. 161–170.
of ~1 m.y./cycle in the Early and ~1.4 m.y./ of the Triassic and their identification in the Jacobs, D.K., and Sahagian, D.L., 1993, Climate
cycle in the Middle Triassic). However, for Western Canada Sedimentary Basin: Bulletin induced fluctuations in sea level during nongla-
the multiple million-year cycles of the Late of Canadian Petroleum Geology, v. 45, no. 4, cial times: Nature, v. 361, p. 710–712, https://
Triassic (average of ~3.6 m.y./cycle, but as p. 415–433. doi.org/10.1038/361710a0.
large as ~7 m.y. for the longest Triassic Flament, N., Gurnis, M., and Mueller, R. D., 2013, Krystyn, L., Balini, M., and Nicora, A., 2005, Low-
er and Middle Triassic Stage and Substage
A review of observations and models of dynamic
cycle in late Norian), we may want to look topography: Lithosphere, v. 5, p. 189–210, https:// Boundaries in Spiti, in Raju, D.S.D., Peters, J.,
for explanations in dynamic topographic doi.org/10.1130/L245.1. Shanker, R., and Kumar, G., eds., An overview
8 GSA Today | December 2018