Peter Molnar
 |
Professor of Geological Sciences, University of
Colorado at Boulder
Fellow, Cooperative Institute for Research in Environmental Sciences
Ph.D., Geology (Seismology), 1970, Columbia University
A.B., Physics, 1965, Oberlin College |
Research Interests:
My current research focuses largely on aspects of how mountain ranges form and continental
lithosphere deforms, two other topics challenge me at present: relationships between the
tectonic evolution of the Earth and climate change, and the impact of climate change on
erosion and the creation of relief. My work on the first includes three broad directions:
(a) the kinematics of continental deformation, for which I rely largely on geophysical
methods; (b) the structure of the crust and upper mantle: and (c) numerical
experimentation on simple systems to understand how mass and heat are transferred in the
continental lithosphere.
1. Deformation of continental lithosphere and mountain
building:
(a) Kinematics of continental deformation. I am currently involved in
studies using GPS measurements to quantify active deformation in parts of Asia and across
the Southern Alps of New Zealand. Though temporarily at present, my work does not include
geologic study of Quaternary faulting and average rates of slip on faults, I keep abreast
of such data as it accumulates. Philip England and I continue to assimilate and synthesize
such data to construct internally consistent velocity and strain-rate fields as keys to
constraining the dynamics of continental deformation. Finally, I remain involved in the
application of leaf-margin analysis to paleoaltimetry, in order to use past mean
elevations of high terrain to place a tight constraint on deeper processes (geological
methodology is otherwise nearly blind to paleoaltimetry).
Some relevant publications:
| Zhang, P.-Z., P. Molnar, and X.-w. Xu (2007), Late Quaternary and present-day
rates of slip along |
|
the Altyn Tagh Fault, northern margin of the Tibetan Plateau, Tectonics, 26,
TC5010, doi:10.1029/2006TC002014. |
| Garzione, C. N.,
P. Molnar, J. C. Libarkin, and B, MacFadden (2006), Rapid Late Miocene rise |
|
of the Bolivian Altiplano: Evidence for removal of
mantle lithosphere, Earth Planet. Sci. Lett, 241, 543-556. |
| Garzione, C. N., P. Molnar, J. C. Libarkin, and B. J. MacFadden (2007), Reply
to Comment on |
|
"Rapid late Miocene rise of the Bolivian Altiplano: Evidence for removal
of mantle lithosphere" by Garzione et al. (2006), Earth Planet. Sci. Lett. 241 (2006)
543-556, Earth and Planetary Science Letters, 259, 630-633. |
| Molnar, P., G. A. Houseman, and P. C. England (2006), Palaeo-altimetry of
Tibet, Nature, 444, E4. |
| England, P.,
and P. Molnar (2005), Late Quaternary to decadal velocity fields in Asia, J. Geophys.
|
|
Res., 110, B12401, doi:10.1029/2004JB003541. |
| Brown, E. T., P.
Molnar, and D. L. Bourlès (2005), Technical comment on "Slip-rate measurements |
|
on the Karakorum Fault may imply secular variations in
fault motion," Science, 309, 1326b. |
| Beavan, J., D. Matheson, P. Denys, M. Denham, T. Herring, B. Hager, and P.
Molnar (2004), |
|
A vertical deformation profile across the Southern Alps, New Zealand, from
3.5 years of continuous GPS data, Proceedings of the Workshop: The state of GPS vertical
positioning precision: Separation of earth processes by space geodesy, ed. by T. van Dam
and O. Francis, Cahiers de Centre Européen de Géodynamique et Séismologie, vol. 23,
Luxembourg, 111-123. |
| Jade, S., B. C. Bhatt, R. Bendick, V. K. Gaur, P. Molnar, M. B. Anand, and
D. Kumar (2004), |
|
GPS measurements from the Ladakh Himalaya, India: Preliminary tests of
plate-like or continuous deformation in Tibet, Geol. Soc. Amer. Bull., 116,
1385-1391. |
| Zhang,
P.-Z., Z.-k. Shen, M. Wang, W.-j. Gan, R. Bürgmann, P. Molnar, Q. Wang, Z.-j. Niu, J.-z.
Sun, |
|
J.-c.
Wu, Sun Hanrong, and You Xinzhao (2004), Continuous deformation of the Tibetan Plateau
from global positioning system data, Geology, 32, 809-812. |
| Thompson,
S. C., R. J. Weldon, C. M. Rubin, K. Abdrakhmatov, P. Molnar, and G. W. Berger, Late |
|
Quaternary
slip rates across the central Tien Shan, Kyrgyzstan, central Asia, J. Geophys. Res., 107,
10.1029/2001JB000596, 2002. |
| Brown,
E. T., R. Bendick, D. L. Bourlès, V. K. Gaur, P. Molnar, G. M. Raisbeck, and F. Yiou,
Slip |
|
rates
of the Karakorum fault, Ladakh, India, determined using cosmic ray exposure dating of
debris flows and moraines, J. Geophys. Res., 107, 10.1029/2000JB000100, 2002. |
| Abdrakhmatov,
K. E., R. Weldon, S. Thompson, D. Burbank, Ch. Rubin, M. Miller, and P. Molnar, |
|
Origin,
direction, and rate of modern compression in the central Tien Shan, Kyrgyzstan, GEOLOGIYA
I GEOFIZIKA (RUSSIAN GEOLOGY & GEOPHYSICS), 42, 1585-1609, 2001. |
| Hallet,
B., and P. Molnar, Distorted drainage basins as markers of crustal strain east of the
Himalaya, |
|
J.
Geophys. Res., 106, 13,697-13,709, 2001. |
| Forest,
C. E., J. A. Wolfe, P. Molnar, and K. A. Emanuel, Paleoaltimetry incorporating atmospheric
|
|
physics
and botanical estimates of paleoclimate, Geol. Soc. Amer. Bull., 111, 497-511, 1999. |
| Wolfe,
J. A., C. E. Forest, and P. Molnar, Paleobotanical evidence of Eocene and Oligocene |
|
paleoaltitudes
in midlatitude western North America, Geol. Soc. Am. Bull., 110, 664-678, 1998. |
| Brown,
E. T., D. L. Bourlès, B. C. Burchfiel, Deng Qidong, Li Jun, P. Molnar, G. M. Raisbeck,
and F. |
|
Yiou,
Estimation of slip rates in the southern Tien Shan using cosmic ray exposure dates of
abandoned alluvial fans, Geol. Soc. Amer. Bull., 110, 377-386, 1998. |
| Wolfe, J. A., H. E. Schorn, C. E. Forest, and P. Molnar, Paleobotanical
evidence for high altitudes in |
|
Nevada during the Miocene, Science, 276, 1672-1675, 1997. |
| England, P., and P. Molnar, The field of crustal velocity in Asia calculated
from Quaternary rates of |
|
slip on faults, Geophys. J. Int.,
130, 551-582, 1997. |
| Abdrakhmatov,
K. Ye., S. A. Aldazhanov, B. H. Hager, M. W. Hamburger, T. A. Herring, K. B. |
|
Kalabaev,
V. I. Makarov, P. Molnar, S. V. Panasyuk, M. T. Prilepin, R. E. Reilinger, I. S.
Sadybakasov, B. J. Souter, Yu. A. Trapeznikov, V. Ye. Tsurkov, and A. V. Zubovich,
Relatively recent construction of the Tien Shan inferred from GPS measurements of
present-day crustal deformation rates, Nature, 384, 450-453, 1996. |
| Burtman,
V. S., S. F. Skobelev, and P. Molnar, Late Cenozoic slip on the Talas-Ferghana fault, the |
|
Tien
Shan, central Asia, Geol. Soc. Amer. Bull., 108, 1004-1021, 1996. |
| Bayarsayhan,
Ch., A. Bayasgalan , B. Enhtuvshin, K. W. Hudnut, R. A. Kurushin, P. Molnar, and M. |
|
Ölziybat,
1957 Gobi-Altay, Mongolia earthquake as a prototype for southern California's most
devastating earthquake, Geology, 24, 579-582, 1996. |
| Molnar, P. and J. M. Gipson, A bound on the rheology of continental
lithosphere using very long |
|
baseline interferometry: The velocity of South China with respect to Eurasia,
J. Geophys. Res., 101, 545-553, 1996. |
| Forest,
C. E., P. Molnar, and K. A. Emanuel, Palaeoaltimetry from energy conservation principles, |
|
Nature,
374, 347-350, 1995. |
| Molnar, P., and J. M. Gipson, Very long baseline interferometry and active
rotations of crustal blocks |
|
in the Western Transverse Ranges, California, Geol. Soc. Amer. Bull., 106,
594-606, 1994. |
| Zhang
Peizhen, B. C. Burchfiel, P. Molnar, Zhang Weiqi, Jiao Dechen, Deng Qidong, Wang Yipeng, |
|
L.
Royden, and Song Fangmin, Amount and style of late Cenozoic deformation in the Liupan Shan
area, Ningxia Autonomous Region, China, Tectonics, 10, 1111-1129, 1991. |
| Burchfiel,
B. C., Zhang Peizhen, Wang Yipeng, Zhang Weiqi, Song Fangmin, Deng Qidong, P. |
|
Molnar,
and L. Royden, Geology of the Haiyuan fault zone, Ningxia-Hui Autonomous Region, China,
and its relation to the evolution of the northeastern margin of the Tibetan plateau,
Tectonics, 10, 1091-1110, 1991. |
| Ménard,
G., P. Molnar, and J. P. Platt, Budget of crustal shortening and subduction of continental
|
|
crust
in the Alps, Tectonics, 10, 231-244, 1991. |
| Jackson, J., and P. Molnar, Active faulting and block rotations in the
western Transverse Ranges, |
|
California, J. Geophys. Res., 95, 22,073-22,087, 1990. |
| Chen, W.-P., and P. Molnar, Source parameters of earthquakes and intraplate
deformation beneath |
|
the Shillong Plateau and northern Indoburman Ranges, J. Geophys. Res., 95,
12,527-12,552, 1990. |
| England, P., and P. Molnar, Surface uplift, uplift of rocks, and exhumation
of rocks, Geology, 18, |
|
1173-1177, 1990. |
| England,
P., and P. Molnar, Right-lateral shear and rotation as the explanation for strike-slip
faulting |
|
in
eastern Tibet, Nature, 344,140-142, 1990. |
| Zhang
Peizhen, B. C. Burchfiel, P. Molnar, Zhang Weiqi, Jiao Decheng, Deng Qidong, Wang Yipeng, |
|
L.
Royden, and Song Fangmin, Late Cenozoic tectonic evolution of the Ningxia-Hui Autonomous
Region, China, Geol. Soc. Amer. Bull., 102, 1484-1498, 1990. |
| Molnar, P., and H. Lyon-Caen, Fault plane solutions of earthquakes and active
tectonics of the |
|
Tibetan Plateau and its margins,
Geophys. J. Int., 99, 123-153, 1989. |
| Kidd,
W. S. F., and P. Molnar, Quaternary and active faulting observed on the 1985 Academia |
|
Sinica-Royal
Society geotraverse of Tibet, Phil. Trans. Roy. Soc. Lond., Ser. A, 327, 337-363, 1988. |
| Zhang
Peizhen, P. Molnar, Zhang Weiqi, Deng Qidong, Wang Yipeng, B. C. Burchfiel, Song |
|
Fangmin,
L. Royden, and Jiao Decheng, Bounds on the recurrence interval of major earthquakes along
the Haiyuan fault in north-central China, Seismol. Res. Lett., 59, 81-89, 1988. |
| Zhang
Peizhen, P. Molnar, B. C. Burchfiel, L. Royden, Wang Yipeng, Deng Qidong, Song Fangmin, |
|
Zhang
Weiqi, and Jiao Decheng, Bounds on the Holocene slip rate of the Haiyuan fault,
north-central China, Quaternary Research, 30, 151-164, 1988. |
| Pandey, M. R., and P. Molnar, The distribution of intensity of the
Bihar-Nepal earthquake of 15 |
|
January 1934 and bounds on the extent of the rupture zone, J. Geol. Soc.
Nepal, 5, 22-44, 1988. |
| Ménard,
G., and P. Molnar, Collapse of a Hercynian Tibetan Plateau into a late Palaeozoic Basin
and |
|
Range
Province in southern Europe, Nature, 334, 235-237, 1988. |
| Molnar,
P., Inversion of profiles of uplift rates for the geometry of dip-slip faults at depth,
with |
|
examples
from the Alps and the Himalaya, Annales Geophysicae, 5B, 663-670, 1987. |
| Nelson,
M. R., R. McCaffrey, and P. Molnar, Source parameters for 11 earthquakes in the Tien Shan,
|
|
Central
Asia, determined by P and SH waveform inversion, J. Geophys. Res., 92, 12,629-12,648,
1987. |
| Zhang
Weiqi, Jiao Decheng, Zhang Peizhen, P. Molnar, B. C. Burchfiel, Deng Qidong, and Wang |
|
Yipeng,
Displacement along the Haiyuan fault associated with the great 1920 Haiyuan, China,
earthquake, Bull. Seismo. Soc. Amer. 77, 117-181, 1987. |
| Molnar,
P., B. C. Burchfiel, Zhao Ziyun, Liang K'uangyi, Wang Shuji, and Huang Minmin, The
geologic |
|
evolution
of northern Tibet: Results from an expedition to Ulugh Muztagh, Science, 235, 299-304,
1987. |
| Chang
Chengfa, Chen Nansheng, M. P. Coward, Deng Wanming, J. F. Dewey, A. Gansser, N. B. W. |
|
Harris,
Jin Chengwei, W. S. F. Kidd, M. R. Leeder, Li Huan, Lin Jinlu, Liu Chengjie, Mei Houjun,
P. Molnar, Pan Yun, Pan Yusheng, J. A. Pearce, R. M. Shackleton, A. B. Smith, Sun Yiyin,
M. Ward, D. Watts, Xu Juntao, Xu Ronghua, Yin Jixiang, and Zhang Yuquan, Preliminary
conclusions of the Royal Society and Academia Sinica 1985 geotraverse of Tibet, Nature,
323, 501-507, 1986. |
| Baranowski,
J., J. Armbruster, L. Seeber, and P. Molnar, Focal depths and fault plane solutions of |
|
earthquakes
and active tectonics of the Himalaya, J. Geophys. Res., 89, 6918-6928, 1984. |
| Molnar, P. and Deng Qidong, Faulting associated with large earthquakes and
the average rate of |
|
deformation in central and eastern Asia, J. Geophys. Res., 89, 6203-6227,
1984. |
| Deng
Qidong, Song Fangmin, Zhu Shilong, Li Mengluan, Wang Tielin, Zhang Weiqi, B. C. Burchfiel,
|
|
P.
Molnar, and Zhang Peizhen, Active faulting and tectonics of the Ningxia-Hui Autonomous
Region, China, J. Geophys. Res., 89, 4427-4445, 1984. |
| Le
Dain, A. Y., P. Tapponnier, and P. Molnar, Active faulting and tectonics of Burma and
surrounding |
|
regions,
J. Geophys. Res., 89, 453-472, 1984. |
| Suárez,
G., P. Molnar and B. C. Burchfiel, Seismicity, fault plane solutions, depth of faulting
and |
|
active
tectonics of the Andes of Peru, Ecuador and southern Colombia, J. Geophys. Res., 88,
10,403-10,428, 1983. |
| Molnar, P. and W.-P Chen, Focal depths and fault plane solutions of
earthquakes under the Tibetan |
|
plateau, J. Geophys. Res., 88,
1180-1196, 1983. |
| Molnar,
P., Average regional strain due to slip on numerous faults of different orientations, J. |
|
Geophys.
Res., 88, 6430-6432, 1983. |
| Molnar, P. and W.-P. Chen, Seismicity and Mountain Building, in Mountain
Building Processes, K. |
|
Hsu, ed., Academic Press, London, 41-57, 1982. |
| Chen,
W.-P., J. L. Nábelek, T. J. Fitch, and P. Molnar, An intermediate depth earthquake
beneath |
|
Tibet:
Source characteristics of the event of September 14, 1976, J. Geophys. Res., 86,
2863-2876, 1981. |
| Chatelain,
J.-L., S. W. Roecker, D. Hatzfeld, and P. Molnar, Microearthquake seismicity and fault |
|
plane
solutions in the Hindu-Kush region and their tectonic implications, J. Geophys. Res., 85,
1365-1387, 1980. |
| Jackson,
J., P. Molnar, H. Patton, T. J. Fitch, Seismotectonic aspects of the Markansu Valley, |
|
Tadjikstan,
earthquake of August 11, 1974, J. Geophys. Res., 84, 6157-6167, 1979. |
| Tapponnier, P. and P. Molnar, Active faulting and Cenozoic tectonics of the
Tien Shan, Mongolia and |
|
Baykal Regions, J. Geophys. Res.,
84, 3425-3459, 1979. |
| Molnar, P. and P. Tapponnier, Active tectonics of Tibet, J. Geophys. Res.,
83, 5361-5375, 1978. |
|
|
| Chen, W.-P. and P. Molnar, Seismic moments of major earthquakes and the
average rate of slip in |
|
Central Asia, J. Geophys. Res., 82, 2945-2969, 1977. |
| Tapponnier, P. and P. Molnar, Active faulting and tectonics of China, J.
Geophys. Res., 82, |
|
2905-2930, 1977. |
| Molnar, P. and P. Tapponnier, Cenozoic tectonics of Asia: Effects of a
continental collision, Science, |
|
189, 419-426, 1975. |
| Molnar,
P., T. J. Fitch, and F. T. Wu, Fault plane solutions of shallow earthquakes and
contemporary |
|
tectonics
in Asia, Earth Planet. Sci. Lett., 19, 101-112, 1973. |
(b) Deep structure of mountain belts. My
interests include constraining the extent to which faults penetrate the Moho and extend
into the mantle, the degree to which flow within the crust might occur, the role of the
mantle lithosphere and in particular how we might quantify its deformation. Toward the
first, I have been involved with a study (by Charles Wilson as part of his PhD work at CU)
using receiver functions to determine whether the Moho beneath the Marlborough faults in
New Zealand offset the Moho or diffuse into broad shears zones within the crust.
Currently, I work with Nikolai Shapiro and Mike Ritzwoller (Physics Department, CU) on
anisotropy within the crust of Tibet. Finally, I will be involved in a study of anisotropy
beneath New Zealand to quantify the extent to which it can be used as a strain gauge for
mantle deformation. My role in these seismological studies is modest, but as my initial
graduate training was in seismology, and seismology offers the highest resolution of
crustal and mantle structure, I stay as involved as I can in such work.
Some relevant publications:
| Wilson, C. K., C. H. Jones, P. Molnar, A. F. Sheehan, and O. S. Boyd
(2004), Distributed |
|
deformation in the lower crust and upper mantle beneath a continental
strike-slip fault zone: Marlborough fault system, South Island, New Zealand, Geology,
32, 837-840. |
| Shapiro,
N. M., M. H. Ritzwoller, P. Molnar, and V. Levin (2004), Thinning and flow of Tibetan
crust |
|
constrained
by the seismic anisotropy, Science, 305, 233-236. |
| Gilbert,
H. J., A. F. Sheehan, K. G. Dueker, and P. Molnar, Receiver functions in the western
United |
|
States,
with implications for upper mantle structure and dynamics, J. Geophys. Res., 108(B5),
2229, doi:10.1029/2001JB001194, 2003. |
| Scherwath,
M., A. Melhuish, T. Stern, and P. Molnar, Pn anisotropy and distributed upper mantle |
|
deformation
associated with a continental transform fault, Geophys. Res. Lett., 29(8),
10.1029/2001GL014179, 2002. |
| Stern,
T., P. Molnar, D. Okaya, and D. Eberhart-Philips, Teleseismic P wave delays and modes of |
|
shortening
the mantle lithosphere beneath South Island, New Zealand, J. Geophys. Res., 105,
21,615-21,632, 2000. |
| Burov,
E. B., and P. Molnar, Gravity anomalies over the Ferghana Valley (central Asia) and |
|
intracontinental
deformation, J. Geophys. Res., 103, 18,137-18,152, 1998. |
| Woodward,
R. L., and P. Molnar, Lateral heterogeneity in the upper mantle and SS-S traveltime |
|
intervals
for SS rays reflected from the Tibetan Plateau and its surroundings, Earth Planet. Sci.
Lett., 135, 139-148, 1995. |
| Pandey,
M. R., S. W. Roecker, and P. Molnar, P-wave residuals at stations in Nepal: evidence for a
|
|
high
velocity region beneath the Karakorum, Geophys. Res. Lett., 18, 1909-1912, 1991. |
| Molnar,
P., S-wave residuals from earthquakes in the Tibetan region and lateral variations in the |
|
upper
mantle, Earth Planet. Sci. Lett., 101, 68-77, 1990. |
| Burov,
E. V., M. G. Kogan, H. Lyon-Caen and P. Molnar, Gravity anomalies, the deep structure, and
|
|
dynamic
processes beneath the Tien Shan, Earth Planet. Sci. Lett, 96, 367-383, 1990. |
| Lyon-Caen, H., and P. Molnar, Constraints on the deep structure and dynamic
processes beneath the |
|
Alps and adjacent regions from an
analysis of gravity anomalies, Geophys. J. Int., 99, 19-32, 1989. |
| M.I.T.
1985 Field Geophysics Course and Shawn Biehler, A geophysical investigation of the
northern |
|
Panamint
Valley, Inyo County, California: Evidence for possible low angle normal faulting at
shallow depth in the crust, J. Geophys. Res., 92, 10,427-10,441, 1987. |
| Lyon-Caen,
H. and P. Molnar, Gravity anomalies, flexure of the Indian plate, and the structure,
support |
|
and
evolution of the Himalaya and Ganga Basin, Tectonics, 4, 513-538, 1985. |
| Lyon-Caen,
H. and P. Molnar, Gravity anomalies and the structure of western Tibet and the southern |
|
Tarim
Basin, Geophys. Res. Lett., 11, 1251-1254, 1984. |
| Molnar, P. and W.-P. Chen, S-P wave travel time residuals and lateral
inhomogeneity in the mantle |
|
beneath Tibet and the Himalaya, J. Geophys. Res., 89, 6911-6917, 1984. |
| Grange,
F., D. Hatzfeld, P. Cunningham, P. Molnar, S. W. Roecker, G. Suárez, A. Rodriques, and L.
|
|
Ocola,
Microearthquake seismicity and fault plane solutions in southern Peru, J. Geophys. Res.,
89, 6139-6152, 1984. |
| Lyon-Caen, H. and P. Molnar, Constraints on the structure of the Himalaya
from an analysis of gravity |
|
anomalies and a flexural model of the lithosphere, J. Geophys. Res., 88,
8171-8191, 1983. |
| Chen,
W.-P. and P. Molnar, Constraints on the seismic wave velocity structure beneath the
Tibetan |
|
Plateau
and their tectonic implications, J. Geophys. Res., 86, 5937-5962, 1981. |
| Khalturin,
V. I., T. G. Rautian, and P. Molnar, The spectral content of Pamir-Hindu Kush intermediate
|
|
depth
earthquakes: Evidence for a high-Q zone in the upper mantle, J. Geophys. Res., 82,
2931-2943, 1977. |
| Ruzaikin,
A. I., I. L. Nersesov, V. I. Khalturin, and P. Molnar, Propagation of Lg and lateral
variations in |
|
crustal
structure in Asia, J. Geophys. Res., 82, 307-316, 1977. |
| Molnar,
P., W.-P. Chen, T. J. Fitch, P. Tapponnier, W. E. K. Warsi, and F. T. Wu, Structure and |
|
tectonics
of the Himalaya: A brief summary of relevant geophysical observations, Collogue
Internationaux du CNRS, No. 268, Himalaya: Sciences de la Terre, Editions du Centre
National de la Recherche Scientifique, Paris, 269-294, 1977. |
(c) The mechanics of continental deformation. My
current work exploits simplified aspects of large-scale deformation. Katherine Dayem (CU
graduate student), Gregory Houseman (Leeds University), and I are carrying out numerical
experiments on a thin viscous sheet to understand the role of strong regions embedded in a
viscously deforming lithosphere, with the goals of understanding how localized strain
(faulting) might develop. Houseman and I use Rayleigh-Taylor instability to understand how
both non-Newtonian viscosity and the low-density, buoyant overlying crust affects
gravitational instability of thickened mantle lithosphere, as should occur beneath
mountain belts. One goal is constrain the plausible viscosity structure for continental
lithosphere, and an application of scaling laws developed by Houseman and others allowed
Craig Jones and me to test flow laws for olivine, measured in the laboratory.
Some relevant publications:
| Jaupart, C., P. Molnar, and E. Cottrell (2007),
Instability of a chemically dense layer heated from |
|
below and overlain by a deep less viscous fluid, J.
Fluid Mech., 572, 433-469. |
| Molnar, P., and C. N. Garzione (2007), Bounds on the
viscosity coefficient of continental lithosphere |
|
from removal of mantle lithosphere beneath the
Altiplano and Eastern Cordillera, Tectonics, 26, TC2013, doi:10.1029/2006TC001964. |
| Hilley, G. E., R.
Bürgmann, P.-Z. Zhang, and P. Molnar (2005), Bayesian inference of plastosphere |
|
viscosities near
the Kunlun Fault, northern Tibet, Geophys. Res. Lett., 32, L01302, doi:10.1029/
2004GL021658. |
| Cottrell, E., C. Jaupart, and P. Molnar (2004), Marginal stability of thick
continental lithosphere, |
|
Geophys. Res. Lett., 31, L18612, doi:10.1029/2004GL020332. |
| Molnar, P., and G. A. Houseman (2004), Effects of buoyant crust on the
gravitational instability of |
|
thickened mantle lithosphere at
zones of intracontinental convergence, Geophys. J. Int., 158, 1134-1150. |
| Molnar,
P., and C. H. Jones (2004), A test of laboratory based rheological parameters of olivine
from |
|
an
analysis of late Cenozoic convective removal of mantle lithosphere beneath the Sierra
Nevada, California, USA, Geophys. J. Int., 156, 555-564. |
| Von
Herzen, R., C. Ruppel, P. Molnar, M. Nettles, S. Nagihara, and G. Ekström, A Constraint
on the |
|
shear
stress at the Pacific-Australia plate boundary from heat flow and seismicity at the
Kermadec forearc, J. Geophys. Res., 106, 6817-6833, 2001. |
| Molnar,
P., H. J. Anderson, E. Audoine, D. Eberhart-Phillips, K. R. Gledhill, E. R. Klosko, T. V. |
|
McEvilly,
D. Okaya, M. K. Savage, T. Stern, and F. T. Wu, Continuous Deformation Versus Faulting
through the Continental Lithosphere of New Zealand, Science, 286, 516-519, 1999. |
| Conrad, C. P., and P. Molnar, Convective instability of a boundary layer with
temperature- and |
|
strain-rate-dependent viscosity in terms of 'available buoyancy,' Geophys. J.
Int., 139, 51-68, 1999. |
| Molnar,
P., G. A. Houseman, and C. P. Conrad, Rayleigh-Taylor instability and convective thinning
of |
|
mechanically
thickened lithosphere: effects of non-linear viscosity decreasing exponentially with depth
and of horizontal shortening of the layer, Geophys. J. Int., 133, 568-584, 1998. |
| England,
P., and P. Molnar, Active deformation of Asia: from kinematics to dynamics, Science, 278, |
|
647-650,
1997. |
| Houseman,
G. A., and P. Molnar, Gravitational (Rayleigh-Taylor) instability of a layer with
non-linear |
|
viscosity
and convective thinning of continental lithosphere, Geophys. J. Int., 128, 125-150, 1997. |
| Conrad, C. P., and P. Molnar, The growth of Rayleigh-Taylor-type
instabilities in the lithosphere for |
|
various rheological and density structures, Geophys. J. Int., 129, 95-112,
1997. |
| Martinod, J., and P. Molnar, Lithospheric folding in the Indian Ocean and the
rheology of the oceanic |
|
plate, Bull. Soc. géol. France, 166, 813-821, 1995. |
| Molnar, P., and P. England, Temperatures in zones of steady-state
underthrusting of young oceanic |
|
lithosphere, Earth Planet. Sci.
Lett, 131, 57-70, 1995. |
| England, P., and P. Molnar, Cause and effect among thrust and normal
faulting, anatectic melting and |
|
exhumation in the Himalaya, in Himalayan Tectonics, Geol. Soc. (of London)
Spec. Pub., 74, ed. by P. J. Treloar and M. P. Searle, 401-411, 1993. |
| England, P., and P. Molnar, The interpretation of inverted metamorphic
isograds using simple |
|
physical calculations, Tectonics, 12, 145-157, 1993. |
| Molnar,
P., Crust in mantle overdrive, Nature, 358, 105-106, 1992. |
|
|
| Molnar,
P., Brace-Goetze strength profiles, the partitioning of strike-slip and thrust faulting at
zones of |
|
oblique
convergence, and the stress-heat flow paradox of the San Andreas fault, Fault Mechanics
and Transport Properties in Rocks: A Festschrift in Honor of W. F. Brace, ed. by B. Evans
and T.-f. Wong, Academic Press, London, 435-459, 1992. |
| Chatelain,
J. L., P. Molnar, R. Prévot, and B. L. Isacks, Detachment of part of the downgoing slab
and |
|
uplift
of the New Hebrides (Vanuatu) Islands, Geophys. Res. Lett., 19(14), 1507-1510, 1992. |
| England,
P., P. Le Fort, P. Molnar, and A. Pêcher, Heat sources for Tertiary metamorphism and |
|
anatexis
in the Annapurna-Manaslu region central Nepal, J. Geophys. Res., 97, 2107-2128, 1992. |
| England, P., and P. Molnar, Inferences of deviatoric stress in actively
deforming belts from simple |
|
physical models, Phil. Trans. Roy. Soc. Lond. A, 337, 151-164, 1991. |
| Molnar, P., and P. England, Temperatures, heat flux, and frictional stress
near major thrust faults, J. |
|
Geophys. Res., 95, 4833-4856, 1990. |
| Molnar,
P., and H. Lyon-Caen, Some simple physical aspects of the support, structure, and
evolution |
|
of
mountain belts, in Processes in Continental Lithospheric Deformation, Geol. Soc. Amer.
Spec. Pap. 218, 179-207, 1988. |
| Chen, W.-P. and P. Molnar, Focal depths of intracontinental and intraplate
earthquakes and their |
|
implications for the thermal and mechanical properties of the lithosphere, J.
Geophys. Res., 88, 4183-4214, 1983. |
| Dalmayrac, B. and P. Molnar, Parallel thrust and normal faulting in Peru and
constraints on the state |
|
of stress, Earth Planet. Sci. Lett., 55, 473-481, 1981. |
| Molnar, P. and P. Tapponnier, A possible dependence of tectonic strength on
the age of the crust in |
|
Asia, Earth Planet. Sci. Lett., 52, 107-114, 1981. |
| Houseman,
G. A., D. P. McKenzie, and P. Molnar, Convective instability of a thickened boundary |
|
layer
and its relevance for the thermal evolution of continental convergent belts, J. Geophys.
Res., 86, 6115-6132, 1981. |
| Molnar,
P. and D. Gray, Subduction of continental lithosphere: Some constraints and uncertainties,
|
|
Geology,
7, 58-62, 1979. |
| Molnar,
P., D. Freedman, and J. S. F. Shih, Lengths of intermediate and deep seismic zones and |
|
temperatures
in downgoing slabs of lithosphere, Geophys. J. Roy. Astr. Soc., 56, 41-54, 1979. |
| Molnar,
P. and T. Atwater, Interarc spreading and cordilleran tectonics as alternates related to
the |
|
age
of subducted oceanic lithosphere, Earth Planet. Sci. Lett., 41, 330-340, 1979. |
| Molnar, P. and P. Tapponnier, Relation of the tectonics of eastern China to
the India-Eurasia |
|
collision: Application of slip-line field theory to large-scale continental
tectonics, Geology, 5, 212-216, 1977. |
| Tapponnier,
P. and P. Molnar, Slip-line field theory and large-scale continental tectonics, Nature,
264, |
|
319-324,
1976. |
In addition, I have written some review papers on large-scale continental deformation,
both for technical and for more general audiences:
| England, P., P. Molnar, and F. Richter (2007), John
Perry's neglected critique of Kelvin's age for |
|
the Earth: A missed opportunity in geodynamics, GSA
Today, 17(1), 4-9. |
| Molnar,
P. (2005), Mio-Pliocene Growth of the Tibetan Plateau and Evolution of East Asian Climate,
|
|
Palaeontologia
Electronica, 8, 8.1.2A, 23p, 625KB; http://palaeo-electronica.org/paleo/2005_1/molnar2/issue1_05.htm. |
| Molnar,
P., P. England, and J. Martinod, Mantle dynamics, the uplift of the Tibetan Plateau, and
the |
|
Indian
monsoon, Reviews of Geophysics, 31, 357-396, 1993. |
| Molnar,
P., A review of seismicity, recent faulting, and active deformation of the Tibetan
Plateau, J. |
|
Himalayan
Geology, 3 (1), 43-78, 1992. |
| Molnar,
P., A review of the seismicity and the rates of underthrusting and deformation at the |
|
Himalaya,
J. Himalayan Geology 1(2), 131-154, 1990. |
| Molnar,
P., The geologic evolution of the Tibetan Plateau, Amer. Sci., 77, 350-360, 1989. |
|
|
| Molnar,
P., Continental tectonics in the aftermath of plate tectonics, Nature, 335, 131-137, 1988. |
|
|
| Molnar,
P., A review of geophysical constraints on the deep structure of the Tibetan Plateau, the |
|
Himalaya,
and the Karakorum and their tectonic implications, Phil. Trans. Roy. Soc. Lond., Ser. A,
326, 33-88, 1988. |
| Molnar,
P., Ulugh Muztagh: The highest peak on the northern Tibetan Plateau, Alpine J., 92,
104-116, |
|
1987.
|
| Molnar,
P., The Structure of mountain ranges, Sci. Amer., 254, 70-79, July, 1986. |
|
|
| Molnar,
P., The geologic history and structure of the Himalaya, Amer. Sci., 74, 144-154, 1986.
|
|
|
| Molnar,
P., Structure and tectonics of the Himalaya: Constraints and implications of geophysical
data, |
|
Annual
Reviews of Earth and Planetary Sciences, 12, 489-518, 1984. |
| Molnar, P., and P. Tapponnier, The collision between India and Eurasia, Sci.
Amer., 236(4), 30-41, |
|
1977. |
2. Tectonics and Climate:
Large-scale tectonics affects the circulation of the oceans and
atmosphere in two obvious ways: (a) gateways between oceans with different properties can
open or close and thus alter the composition and temperature structure of the oceans, and
(b) the growth of mountain ranges can alter atmospheric circulation. Both attract me. Mark
Cane (Columbia University) and I have argued that the closing of the Indonesian Seaway may
have altered the temperature structure of both the Indian and Pacific Oceans so that East
Africa became wetter over the approximate period when humans evolved, and the present-day
tropical Pacific moved from what was effectively a permanent El Niño condition to the
present, for which El Niño occurs only rarely. My current focus, however, again is toward
determining when the Tibetan Plateau grew to its present-day height and lateral extent,
and how that growth affected both the Indian and the east Asian Monsoons. I hope to become
involved with paleoclimatologists in the drilling of Qinghai, a large lake on the NE edge
of Tibet, among a number of ventures into this field and geographic region.
Some relevant publications:
| Dayem, K. E., D. C. Noone, and P. Molnar (2007), Tropical western Pacific
warm pool and |
|
maritime continent precipitation rates and their contrasting relationships
with the Walker Circulation, J. Geophys. Res., 112, D06101, doi:10.1029/2006JD007870. |
| Molnar, P., and M. A. Cane (2007), Early Pliocene (Pre-Ice Age) El Niño-like
Global Climate: |
|
Which El Niño?, Geosphere, 3(5), 337-365. |
| Huybers, P., and P. Molnar (2007), Tropical cooling and the onset of North
American glaciation, |
|
Clim. Past, 3, 549-557, 2007. |
| Brown,
E. T., R. Bendick, D. L. Bourlès, V. Gaur, P. Molnar, G. M. Raisbeck, and F. Yiou, Early |
|
Holocene
climate recorded in geomorphological features in Western Tibet, Palaeogeography,
Palaeoclimatology, Palaeoecology, 199, 141-151, 2003. |
| Molnar,
P., and M. A. Cane, El Niño's tropical climate and teleconnections as a blueprint for
pre-Ice |
|
Age
climates, Paleoceanography, 17 (2), 10.1029/2001PA000663, 2002. |
| Cane, M.
A., and P. Molnar, Closing of the Indonesian seaway as a precursor to east African |
|
aridification
around 3–4 million years ago, Nature, 411, 157-162, 2001. |
| Molnar, P., and K. A. Emanuel, Temperature profiles in radiative-convective
equilibrium above |
|
surfaces of different heights, J. Geophys. Res., 104, 24,265-24,271, 1999. |
| Gillespie,
A., and P. Molnar, Asynchronous maximum advances of mountain and continental glaciers,
|
|
Rev.
Geophys., 33, 311-364, 1995. |
| Molnar,
P., and P. England, Late Cenozoic uplift of mountain ranges and global climate change: |
|
chicken
or egg?, Nature, 346, 29-34, 1990. |
3. Climate change and the geomorphology of mountain ranges.
Collaborative work with Zhang Pei-zhen (National Earthquake
Administration, China) suggests that erosion rates increased abruptly approximately when
climate change 3-4 million years ago toward a cooler global climate. This poses the
question of how has such a change affected erosion rates. My working hypotheses are that
the job of rivers is not to erode, but to transport sediment, and that rivers are most
effective is rare large floods. Thus, my foci concern how other processes might convert
bedrock to bedload (such as topographically induced stress in valley floors fracturing
rock by static fatigue), trying to quantify aspects of floods, and measuring erosion rates
in steep terrain (like the Himalaya). With little training in this and without a clearly
articulated strategy, I merely grope forward following hunches that others seem to have
discarded or ignored, mostly for the fun of working in a field with so many pleasant
people.
Some relevant publications:
| Champagnac, J. D., P. Molnar, R. S. Anderson, C. Sue,
and B. Delacou (2007), Quaternary |
|
erosion-induced isostatic rebound in the Western Alps,
Geology, 35, 195-198. |
| Molnar, P., R. S. Anderson, and S. P. Anderson (2007), Tectonics, fracturing
of rock, and erosion, |
|
J. Geophys. Res., 112, F03014, doi:10.1029/2005JF000433. |
| Molnar, P., R. S. Anderson, G. Kier, and J. Rose (2006), Relationships
among probability |
|
distributions of stream discharges in floods, climate, bed load transport,
and river incision, J. Geophys. Res., 111, F02001, doi:10.1029/2005JF000310. |
| Anderson,
R. S., P. Molnar, and M. A. Kessler (2006), Features of glacial valley profiles simply
|
|
explained, J. Geophys Res., 111, F01004,
doi:10.1029/2005JF000344. |
| Molnar,
P. (2004), Interactions among topographically induced elastic stress, static fatigue, and
valley |
|
incision,
J. Geophys. Res., 109, F02010, doi:10.1029/2003JF000097. |
| Molnar,
P. (2004), Late Cenozoic increase in accumulation rates of terrestrial sediment: How might
|
|
climate
change have affected erosion rates?, Ann. Rev. Earth Planet. Sci., 32, 67-89. |
| Molnar,
P., Nature, nurture and landscape, Nature, 426, 612-614, 2003. |
|
|
| Molnar, P., Climate change, flooding in arid environments, and erosion rates,
Geology, 29, |
|
1071-1074, 2001. |
| Zhang
Peizhen, P. Molnar, and W. R. Downs, Increased sedimentation rates and grain sizes
2–4 Myr |
|
ago
due to the influence of climate change on erosion rates, Nature, 410, 891-897, 2001. |
| Molnar,
P., E. T. Brown, B. C. Burchfiel, Deng Qidong, Feng Xianyue, Li Jun, G. M. Raisbeck, Shi |
|
Jianbang,
Wu Zhangming, F. Yiou, and You Huichuan, Quaternary climate change and the formation of
river terraces across growing anticlines on the north flank of the Tien Shan, China, J.
Geol., 102, 583-602, 1994. |
Dormant pursuits. Much of my work when I was a graduate student and for many years alter
focused on aspects of plate tectonics and on earthquakes as mechanic processes. Although I
no longer pursue these vigorously, I list some relevant papers below.
Plate tectonics: Some publications:
| Stock, J., and P. Molnar, Uncertainties and implications of the late
Cretaceous and Tertiary position |
|
of North America relative to the
Farallon, Kula, and Pacific plates, Tectonics, 7, 1339-1384, 1988. |
| Molnar,
P., F. Pardo-Casas, and J. Stock, The Cenozoic and late Cretaceous evolution of the Indian
|
|
Ocean
basin: Uncertainties in the reconstructed positions of the Indian, African, and Antarctic
plates, Basin Res., 1, 23-40, 1988. |
| Rosa, J. W. C., and P. Molnar, Uncertainties in reconstructions of the
Pacific, Farallon, Vancouver, |
|
and Kula plates and constraints
on the rigidity of the Pacific and Farallon (and Vancouver) plates between 72 and 35 Ma,
J. Geophys. Res., 93, 2997-3008, 1988. |
| Molnar,
P. and J. Stock, Relative motions of hotspots in the Pacific, Atlantic, and Indian Oceans
since |
|
late
Cretaceous time, Nature, 327, 587-591, 1987. |
| Pardo-Casas, F. and P. Molnar, Relative motion of the Nazca (Farallon) and
South American plates |
|
since Late Cretaceous time, Tectonics, 6, 233-248, 1987. |
| Stock,
J., and P. Molnar, Revised history of early Tertiary plate motion in the south-west
Pacific, |
|
Nature,
325, 495-499, 1987. |
| Molnar, P. and J. M. Stock, A method for bounding uncertainties in combined
plate reconstructions, J. |
|
Geophys. Res., 90, 12,537-12,544, 1985. |
| Stock, J. M. and P. Molnar, Some geometrical aspects of uncertainties in
combined plate |
|
reconstructions, Geology, 11,
697-701, 1983. |
| Suárez, G. and P. Molnar, Paleomagnetic data and pelagic sediment facies and
the motion of the |
|
Pacific plate relative to the
spin axis since the late Cretaceous, J. Geophys. Res., 85, 5257-5280, 1980. |
| Molnar,
P., Earthquake Recurrence intervals and plate tectonics, Bull. Seismo. Soc. Amer., 69, |
|
115-133,
1979. |
| Bunce,
E. T., and P. Molnar, Seismic reflection profiling and basement topography in the Somali |
|
Basin:
Possible fracture zones between Madagascar and Africa, J. Geophys. Res., 82, 5305-5311,
1977. |
| Shih,
J. and P. Molnar, Analysis and implications of the sequence of ridge jumps that eliminated
the |
|
Surveyor
transform fault, J. Geophys. Res., 80, 4815-4822, 1975. |
| Molnar, P. and J. Francheteau, The relative motion of "hot spots"
in the Atlantic and Indian Oceans |
|
During the Cenozoic, Geophys. J. Roy. Astronom. Soc., 43, 763-774, 1975. |
| Minster,
J. B., T. H. Jordan, P. Molnar, and E. Haines, Numerical modelling of instantaneous plate |
|
tectonics,
Geophys. J. Roy. Astr. Soc., 36, 541-576, 1974. |
| Atwater, T. and P. Molnar, Relative motion of the Pacific and North American
plates deduced from |
|
sea-floor spreading in the
Atlantic, Indian, and South Pacific Oceans, Proc. Conf. on Tectonic Problems of the San
Andreas Fault System, Geological Sciences XIII, School of Earth Sciences, Stanford Univ.
Publications, 136-148, 1973. |
| Molnar,
P. and T. Atwater, Relative motion of hot spots in the mantle, Nature, 246, 288-291, 1973.
|
|
|
| Isacks,
B. and P. Molnar, Distribution of stresses in the descending lithosphere from a global
survey |
|
of
focal-mechanism solutions of mantle earthquakes, Rev. Geophys. Space Phys., 9, 103-174,
1971. |
| Isacks,
B. and P. Molnar, Mantle earthquake mechanisms and the sinking of the lithosphere, Nature,
|
|
223,
1121-1124, 1969. |
| Molnar,
P. and L. R. Sykes, Tectonics of the Caribbean and Middle America regions from focal |
|
mechanisms
and seismicity, Geol. Soc. Am. Bull., 80, 1639-1684, 1969. |
| Molnar,
P. and J. Oliver, Lateral variations of attenuation in the upper mantle and
discontinuities in the |
|
lithosphere,
J. Geophys. Res., 74, 2648-2682, 1969. |
Earthquake mechanics: Some publications:
| Bilham,
R., V. K. Gaur, and P. Molnar, Himalayan seismic hazard, Science, 293, 1442-1444, 2001. |
|
|
| Jones,
L. M., and P. Molnar, Some characteristics of foreshocks and their possible relationship
to |
|
earthquake
prediction and premonitory slip faults, J. Geophys. Res., 84, 3596-3608, 1979. |
| Jones, L. and P. Molnar, Frequency of foreshocks, Nature, 262, 677-679, 1976.
|
|
|
| Molnar,
P., B. E. Tucker, and J. N. Brune, Corner frequencies of P and S waves and models of |
|
earthquake
sources, Bull. Seism. Soc. Am., 63, 2091-2104, 1973. |
| Scholz,
C., P. Molnar, and T. Johnson, Detailed studies of frictional sliding of granite and
implications |
|
for
the earthquake mechanism, J. Geophys. Res., 77, 6392-6406, 1972. |
Finally, conceivably an autobiographical report and a spoof might interest someone:
| Molnar,
P., From Plate Tectonics to Continental Tectonics: An Evolving Perspective of Important |
|
Research,
from a Graduate Student to an Established Curmudgeon, in Plate tectonics: An
Insider’s History of the Modern Theory of the Earth, ed. by N. Oreskes, Westview
Press, Boulder, Colorado, 288-328, 2001. |
| Molnar,
P., The rise of mountain ranges and the evolution of humans: a causal relation?, Irish J.
Earth |
|
Sci.,
10, 199-207, 1990. |
Courses Offered:
Graduate seminar on Geodynamics and Climate: The Tibetan Plateau (Spring, 2001);
“Uplift and Erosion” (Spring, 2002);
The Himalaya and New Zealand (Spring, 2003);
Physics of crust-mantle interactions (Spring, 2004)
Email address: molnar@cires.colorado.edu
Phone: (303)492-4936 / FAX: (303)492-2606
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