Lower Crustal Xenoliths, Chinese Peak Lava Flow, Central Sierra Nevada

Hildreth et al. (2021) analyzed a set of table mountains near the San Joaquin River that are capped by a 9.3 Ma trachyandesite lava flow and concluded that, since the deposition of the volcanic rocks, the table mountains have been tilted 1.07° due to uplift of the central Sierra Nevada. While Gabet (2014) suggested that, under a limited set of conditions, the size of fluvial gravels under the table mountains would support the hypothesis of postdepositional uplift, the authors claimed that their evidence is more definitive. In addition, the authors proposed that the central Sierra Nevada tilted as a rigid block. However, their analyses rely on inferences and assumptions that are not supported by field evidence.

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Nd and Sr isotopic compositions of lower-crustal xenoliths from north Queensland, Australia: Implications for Nd model ages and crustal growth processes

Chemical Geology ◽

10.1016/0009-2541(90)90280-k ◽

1990 ◽

Vol 83 (3-4) ◽

pp. 195-208 ◽

Cited By ~ 58

Author(s):

R.L. Rudnick

Keyword(s):

Crustal Growth ◽

Growth Processes ◽

Isotopic Compositions ◽

Crustal Xenoliths ◽

Lower Crustal

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The petrology of lower crustal xenoliths from the Executive Committee Range, Marie Byrd Land Volcanic Province, West Antarctica

Lithos ◽

10.1016/0024-4937(95)00017-8 ◽

1995 ◽

Vol 36 (3-4) ◽

pp. 185-201 ◽

Cited By ~ 22

Author(s):

R.J. Wysoczanski ◽

J.A. Gamble ◽

P.R. Kyle ◽

M.F. Thirlwall

Keyword(s):

Executive Committee ◽

West Antarctica ◽

Volcanic Province ◽

Crustal Xenoliths ◽

Lower Crustal

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Characterization of crustal xenoliths from the Bearpaw Mountains, Montana (USA), using U-Pb geochronology, whole-rock geochemistry and thermobarometry, with implications for lower crustal processes and evolution of the Wyoming Craton

Chemical Geology ◽

10.1016/j.chemgeo.2019.05.034 ◽

2019 ◽

Vol 524 ◽

pp. 295-322 ◽

Cited By ~ 3

Author(s):

Yashirvad Thakurdin ◽

Robert Bolhar ◽

Péter Horváth ◽

Alexander Rocholl ◽

Kenneth Collerson

Keyword(s):

Wyoming Craton ◽

Crustal Xenoliths ◽

Lower Crustal

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Lower crustal zircons reveal Neogene metamorphism beneath the Pannonian Basin (Hungary)

Open Geosciences ◽

10.1515/geo-2015-0028 ◽

2015 ◽

Vol 7 (1) ◽

Cited By ~ 3

Author(s):

Hilary Downes ◽

Andrew Carter ◽

Richard Armstrong ◽

Gabor Dobosi ◽

Antal Embey-Isztin

Keyword(s):

Pannonian Basin ◽

Granulite Facies ◽

Blocking Temperature ◽

Late Devonian ◽

Alkali Basalts ◽

Volcanic Deposits ◽

Eruption Age ◽

Crustal Xenoliths ◽

Lower Crustal ◽

Variscan Basement

AbstractNeogene alkaline intraplate volcanic deposits in the Pannonian Basin (Hungary) contain many lower crustal granulite-facies xenoliths. U-Pb ages have been determined for zircons separated from a metasedimentary xenolith, using LA-ICPMS and SHRIMP techniques. The zircons show typical metamorphic characteristics and are not related to the hostmagmatism. The oldest age recorded is late Devonian, probably related to Variscan basement lithologies. Several grains yield Mesozoic dates for their cores, which may correspond to periods of orogenic activity. Most of the zircons show young ages, with some being Palaeocene-Eocene, but the majority being younger than 30Ma. The youngest zircons are Pliocene (5.1-4.2 Ma) and coincide with the age of eruptions of the host alkali basalts. Such young zircons, so close to the eruption age, are unusual in lower crustal xenoliths, and imply that the heat flow in the base of the Pannonian Basin was sufficiently high to keep many of them close to their blocking temperature. This suggests that metamorphism is continuing in the lower crust of the region at the present day.

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