Microgranular enclaves as evidence of rapid cooling in granitoid rocks: the case of the Los Pedroches granodiorite, Iberian Massif, Spain

Donaire, Teodosio; Pascual, Emilio Soler; Pin, Christian; Duthou, Jean-Louis

doi:10.1007/s00410-005-0652-0

Cited by 211 publications

(99 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The similar mineral assemblages and isotopic compositions of the MMEs and host granitoids in both plutons, which are considered further in Section 6.2, are commonly used to indicate that the microgranular enclaves crystallized from coeval, cognate host magmas via accumulation (Dahlquist, 2002;Dodge and Kistler, 1990) or chilled margins processes (Donaire et al, 2005;Esna-Ashari et al, 2011;Pascual et al, 2008). The cumulate model has been criticized because it would not be compatible with the small grain size and the fine-grained margins of many enclaves (Donaire et al, 2005;Esna-Ashari et al, 2011).…”

Section: Magma Mixing For Generating the Mafic Microgranular Enclavesmentioning

confidence: 99%

“…The cumulate model has been criticized because it would not be compatible with the small grain size and the fine-grained margins of many enclaves (Donaire et al, 2005;Esna-Ashari et al, 2011). In the chilled margin scenario, microgranular enclaves have high SiO 2 contents (commonly N58 wt.%) (Donaire et al, 2005;Esna-Ashari et al, 2011;Pascual et al, 2008), can be classified as intermediate-felsic microgranular enclaves (Didier and Barbarin, 1991) and the major mafic mineral is biotite (Donaire et al, 2005;Esna-Ashari et al, 2011;Pascual et al, 2008).…”

Section: Magma Mixing For Generating the Mafic Microgranular Enclavesmentioning

confidence: 99%

“…Two other proposals suggest that they are: (1) fragments of recrystallized, refractory metamorphic rocks or of melt residues from the granite source (e.g., Chappell and White, 1991;Chappell and Wyborn, 2012;Chappell et al, 1987); or (2) cumulates of early-formed crystals or chilled margins (e.g., Bonin, 1991;Collins et al, 2006;Donaire et al, 2005;Shellnutt et al, 2010;Tindle and Pearce, 1983). Distinguishing between these scenarios requires the ability to characterize the primary source of both the microgranular enclaves and their host granitoids.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Overlapping Sr–Nd–Hf–O isotopic compositions in Permian mafic enclaves and host granitoids in Alxa Block, NW China: Evidence for crust–mantle interaction and implications for the generation of silicic igneous provinces

Wei

Wang

et al. 2015

Lithos

View full text Add to dashboard Cite

Section: Magma Mixing For Generating the Mafic Microgranular Enclavesmentioning

confidence: 99%

Section: Magma Mixing For Generating the Mafic Microgranular Enclavesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Overlapping Sr–Nd–Hf–O isotopic compositions in Permian mafic enclaves and host granitoids in Alxa Block, NW China: Evidence for crust–mantle interaction and implications for the generation of silicic igneous provinces

Wei

Wang

et al. 2015

Lithos

View full text Add to dashboard Cite

“…Poli, Tommasini & Halliday, 1996;Janousek et al 2004), or cognate enclaves, suggesting that they represent accumulations of fractionated phases (e.g. Nitoi et al 2002;Donaire et al 2005). Structures found in the field are important for deciphering the true genesis of enclaves.…”

Section: A Qmzdmentioning

confidence: 99%

Petrogenetic and tectonic inferences from the study of the Mt Cer pluton (West Serbia)

et al. 2010

View full text Add to dashboard Cite

-The Mt Cer Pluton, Serbia, is a complex laccolith-like intrusion (∼ 60 km 2 ), situated along the junction between the southern Pannonian Basin and northern Dinarides. It intrudes Palaeozoic metamorphic rocks causing weak to strong thermal effects. Based on modal and chemical compositions, four rock-types can be distinguished: (1) metaluminous I-type quartz monzonite/quartz monzodiorite (QMZD); (2) peraluminous S-type two-mica granite (TMG), which intrudes QMZD; (3) Stražanica granodiorite/quartz monzonite (GDS); and (4) isolated mafic enclaves (ME), found only in QMZD. 40 K-39 Ar dating and geological constraints indicate that the main quartz monzonite/quartz monzodiorite body of Mt Cer was emplaced not later than 21 Ma, whereas the emplacement ages of the Stražanica granodiorite/quartz monzonite and two-mica granites are estimated at around 18 and 16 Ma, respectively. The Mt Cer pluton is similar to the Mt Bukulja pluton, some 80 km southwestwards. Genesis of QMZD cannot be interpreted by fractional crystallization coupled with mixing or assimilation. It is best explained by a convection-diffusion process between mantle-derived minette/leucominette magmas and GDS-like magmas followed by two end-member magma mixing. The composition of GDS rocks suggests that GDS-like magmas could have formed by melting of lower crustal lithologies similar to amphibolite/metabasalts. The geochemistry of TMG is reproduced by an Assimilation/Fractional Crystallization model with a ratio of rate of assimilation to rate of fractional crystallization of 0.4, using the compositions of the least evolved TMG of the Bukulja pluton and adjacent metamorphic rocks as proxies for the parental magma and contaminant, respectively. The origin and evolution of the Mt Cer and adjacent Mt Bukulja plutons provide new constraints on the Tertiary geodynamics of the northern Dinarides-southern Pannonian region. The quartz monzonite/quartz monzodiorite is interpreted as a result of the Oligocene post-collisional Dinaride orogen-collapse, which included a limited lithosphere delamination, small-scale mantle upwelling, and melting of the lower crust. By contrast, the two-mica granite magmas formed through melting in shallower crustal levels during the extensional collapse in the Pannonian area.

show abstract

“…An estimated emplacement age of 312 Ma, consistent with geological evidence and approximating several LPB and LPM dates, has been assumed for calculations, in this work and in previous ones (Donaire et al, 1999(Donaire et al, , 2005. In any case, the ca.…”

Section: Fig 1 Sketch Geological Map Of the Los Pedroches Batholithmentioning

confidence: 96%

The significance of microgranular enclaves in assessing the magmatic evolution of a high-level composite batholith: A case on the Los Pedroches Batholith, Iberian Massif, Spain

Pascual

Donaire

2008

Geochem. J.

Self Cite

View full text Add to dashboard Cite

are partly a consequence of the heterogeneities of the Earth's crust, in most cases requiring a case-by-case study of granitoid genesis. In other instances, however, uncertainties are a consequence of an insufficient integration of geochemical information with other geological data (field, petrographic, geophysical, etc.), either by scarcity or ambiguousness.We present here the case of the Los Pedroches batholith (LPB), one of the largest Variscan batholiths in Spain, as an example in which a number of the usual uncertainties in granite genesis can be overcome by a careful integration of geochemical and isotopic data with field and petrographic evidence.There are several reasons making the LPB of particular interest. The geological setting is very well constrained, as there is both compelling evidence and a wide consensus on its intrusion age, its emplacement style, and its main subdivision in two plutonic suites (Larrea et al., 2004). Also, the LPB is very suitable for a mineralogical and geochemical study, as all of the LPB units contain very fresh rocks. In addition, the LPB rocks are remarkably homogeneous at a large scale, particularly in the case of the granodioritic rocks (LPG). For these reasons, we consider the LPB as a good target to build up a model, which could be of major interest, not only at a regional scale, but also with regard to the general role of microgranular enclaves as indicators of magma genesis (Received May 15, 2007; Accepted October 6, 2007) To evaluate the origin and significance of microgranular enclaves hosted by granites, we present new data on two granitoid series belonging to the Los Pedroches Batholith (LPB), SW Iberian Massif, Spain. The two series in the LPB show a distinct contrast in terms of field, petrographic, mineralogical and geochemical data. This contrast also extends to the enclaves, differing in abundance and other features in each of the series considered. Isotopic measurements, however, including 87 Sr/ 86 Sr, ε Nd and δ 18 O data, show no significant, inter-or intra-series contrast throughout the LPB. These data lend additional support to an origin of all the granitoid rocks in the LPB from a single, isotopically homogeneous, lower crustal source. We also suggest that differences between microgranular enclaves in the two LPB granitoid series cannot be related to a different degree of participation of mafic rocks in the genesis of the respective groups: in both cases, microgranular enclaves are better interpreted as autoliths.

show abstract

Microgranular enclaves as evidence of rapid cooling in granitoid rocks: the case of the Los Pedroches granodiorite, Iberian Massif, Spain

Cited by 211 publications

References 37 publications

Overlapping Sr–Nd–Hf–O isotopic compositions in Permian mafic enclaves and host granitoids in Alxa Block, NW China: Evidence for crust–mantle interaction and implications for the generation of silicic igneous provinces

Overlapping Sr–Nd–Hf–O isotopic compositions in Permian mafic enclaves and host granitoids in Alxa Block, NW China: Evidence for crust–mantle interaction and implications for the generation of silicic igneous provinces

Petrogenetic and tectonic inferences from the study of the Mt Cer pluton (West Serbia)

The significance of microgranular enclaves in assessing the magmatic evolution of a high-level composite batholith: A case on the Los Pedroches Batholith, Iberian Massif, Spain

Contact Info

Product

Resources

About