Results 31 to 40 of about 1,033 (170)

RAPAKIVI MAGMATISM IN THE MIDDLE INIRIDA BASIN, GUAINÍA DEPARMENT, COLOMBIA [PDF]

, 2022
In eastern Colombia, the crystalline basement is intruded by several anorogenic granites of Mesoproterozoic age. One of these anorogenic granitic intrusions outcrops in the area of the indigenous Matraca and Danta communities, at the middle ...
Frantz, José Carlos, Amaya, Zeze, Cramer, Thomas, Bonilla, Amed, Franco, José Alejandro, Charão-Marques, Juliana   +5 more
core   +4 more sources

Induced Earthquake Source Parameters, Attenuation, and Site Effects From Waveform Envelopes in the Fennoscandian Shield

Journal of Geophysical Research: Solid Earth, Volume 128, Issue 4, April 2023., 2023
Abstract We analyze envelopes of 233 and 22 ML0.0 to ML1.8 earthquakes induced by two geothermal stimulations in the Helsinki, Finland, metropolitan area. We separate source spectra and site terms and determine intrinsic attenuation and the scattering strength of shear waves in the 3–200 Hz frequency range using radiative transfer based synthetic ...
Tom Eulenfeld, Gregor Hillers, Tommi A. T. Vuorinen, Ulrich Wegler   +3 more
wiley   +1 more source

Secular Evolution of Continents and the Earth System

Reviews of Geophysics, Volume 60, Issue 4, December 2022., 2022
Abstract Understanding of secular evolution of the Earth system is based largely on the rock and mineral archive preserved in the continental lithosphere. Based on the frequency and range of accessible data preserved in this record, we divide the secular evolution into seven phases: (a) “Proto‐Earth” (ca. 4.57–4.45 Ga); (b) “Primordial Earth” (ca. 4.45–
Peter A. Cawood, Priyadarshi Chowdhury, Jacob A. Mulder, Chris J. Hawkesworth, Fabio A. Capitanio, Prasanna M. Gunawardana, Oliver Nebel   +6 more
wiley   +1 more source

Review on geology and mineralization of North Korea (I: Precambrian)

Resource Geology, Volume 71, Issue 4, Page 492-513, October 2021., 2021
The Precambrian geotectonic provinces of North Korea contain continental cores and massifs, active continental margins, and rift zones. The Precambrian strata between the eastern North China Craton (NCC) and North Korea are newly correlated considering rearranged stratigraphy in this review.
Bum Han Lee, Sang‐Mo Koh, Namhoon Kim, Byoung‐Woon You   +3 more
wiley   +1 more source

Reconstructing craton‐scale tectonic events via in situ Rb‐Sr geochronology of poly‐phased vein mineralization

Terra Nova, Volume 33, Issue 5, Page 502-510, October 2021., 2021
Abstract Fault‐ and fracture‐hosted multi‐stage mineral assemblages that formed by fracture reactivation and fluid migration, constitute archives of the tectonic evolution of Precambrian cratons. Complex intergrowth patterns of these mineral records often hinder absolute dating of mineralization events for geological models.
Mikael Tillberg, Henrik Drake, Thomas Zack, Johan Hogmalm, Ellen Kooijman, Mats Åström   +5 more
wiley   +1 more source

Evidence of crustal contamination of mafic rocks associated with rapakivi rocks: an example from the Nordingra complex, Central Sweden

, 2001
Gabbro and leucogabbro are volumetrically important rocks in the Nordingra rapakivi complex, East Central Sweden. Plagioclase, ortho- and clinopyroxenes, and olivine dominate the gabbro.
Andersson, UB, Claesson, S, Lindh, A,, Lundqvist, T   +3 more
core   +5 more sources

Crustal development in relation to granitic magmatism in regard to D/H partition between coexisting hornblende and biotite in the Svecofennian belt [PDF]

Bulletin of the Geological Society of Finland, 1993
Tie-lines in the σD-XFe diagram of hornblende and biotite in Japanese island arc granites give commonly a similar slope to that derived from the equation of Suzuoki-Epstein's experimental work (1976).
Y. Kuroda, T. Yamada, Y. Yamaguchi, H. Sato, Y. Wake, S. Matsuo   +5 more
doaj   +1 more source

The rapakivi granite plutons of Bodom and Obbnäs, southern Finland: petrography and geochemistry [PDF]

Bulletin of the Geological Society of Finland, 1999
The Obbnäs and Bodom granite plutons of southernmost Finland show the typical petrographic and geochemical features of the Proterozoic rapakivi granites in Finland and elsewhere: they cut sharply across the 1900 Ma Svecofennian metamorphic bedrock and ...
P. Kosunen
doaj   +1 more source

Paleomagnetic studies of rapakivi complexes in the Fennoscandian Shield : Implications for the origin of Proterozoic massif-type anorthosite magmatism [PDF]

, 2021
Paleomagnetic studies have been performed on five rapakivi related complexes in Sweden and Finland. Poles of varying quality have been defined and the majority of the similar to 1640-1497 Ma poles are clustering on low latitudinal positions. By combining
Elming, Sten-åke,, Mertanen, Satu, Almqvist, Bjarne,, Mertanen, Satu,, Moakhar, Mohsen Oveisy,, Salminen, Johanna,, Wang, Chong, Salminen, Johanna, Almqvist, Bjarne, Wang, Chong,, Elming, Sten-Ake, Moakhar, Mohsen Oveisy, Bjarne Almqvist, Chong Wang, Satu Mertanen, Johanna Salminen, Sten-Åke Elming, Mohsen Oveisy Moakhar   +17 more
core   +1 more source

Anorogenic granitoids of the Early Precambrian magmatism of the Ukrainian shield [PDF]

Bulletin of the Geological Society of Finland, 1993
The Early Precambrian magmatism of the Ukrainian shield evolved through regular changes in tectonic setting, composition and depth of formation of rocks of three magmatic associations: (1) granitic, (2) diorite-granitic and (3) anorthosite-granitic. They
K.I. Sveshnikov, Y.T. Sukhorukov, I.K. Pashkevich, S.S. Krasovsky   +3 more
doaj   +1 more source