Emplacement and fabric-forming conditions of plutons from structural and magnetic fabric analysis: A case study of the Plana pluton (Central Bulgaria)

Crystal Mush Flow in Small Concentrically Expanded Pluton (Castle Crags Pluton; Klamath Mountains, CA, USA)

“…Two distinct types of correlation between the high P values and magnetic susceptibility were recorded (Figures c and a). (1) The linear correlation with a high slope represents samples from fine‐grained granodiorite affected by subsolidus overprint, which is in agreement with observation of subsolidus overprint of the original magmatic fabric made by Georgiev et al (). (2) Majority of the high P samples from porphyritic and fine‐grained granodiorite exhibits nonlinear distribution trend in the P versus K m plot (Figures c and a) typical for fabrics resulting from magmatic flow.…”

“…Geochemistry, Geophysics, Geosystems magnetic susceptibility were recorded (Figures 6c and 9a). (1) The linear correlation with a high slope represents samples from fine-grained granodiorite affected by subsolidus overprint, which is in agreement with observation of subsolidus overprint of the original magmatic fabric made by Georgiev et al (2014).…”

“…The present data set revealed rimward increase of the AMS degree to anomalously high P ‐values carried by magnetite in a substantial part of the porphyritic granodiorite and marginal fine‐grained granodiorite. These high‐values are not typical for magmatic fabrics defined by alignment of noninteracting magnetite particles during the magmatic flow in ferromagnetic granites (Georgiev et al, ; Ježek et al, ; Tarling & Hrouda, ). Such anomalously high values have been previously explained either by (1) hematite content (Tarling & Hrouda, ), (2) magnetostatic interactions between adjacent magnetite grains (Cañón‐Tapia, ; Fanjat et al, ; Gaillot et al, ; Gregoire et al, ; Hargraves et al, ), or (3) subsolidus overprint of magmatic fabric (Georgiev et al, ; Henry et al, ; Hrouda & Lanza, ; Nouar et al, ).…”

Tectonic, magmatic, and metallogenic evolution of the Late Cretaceous arc in the Carpathian‐Balkan orogen

“…Hence, pluton emplacement partly overlaps with the age span of the volcano‐sedimentary parts of the Panagyurishte and Timok Basins. This suggests opening of the Panagyurishte and Timok Basins in a scenario of crustal‐scale dextral strike‐slip motion, interpreted in terms of dextral transpression by previous authors [ N. Georgiev et al , ; Naydenov et al , ; Georgiev et al , ]. However, a transtensional rather than transpressional setting is indicated for two reasons: (1) the Iskar‐Yavoritsa shear zone is contemporaneous with the opening of comagmatic transtensional basins [ Naydenov et al , ] and (2) the Iskar‐Yavoritsa shear zone is confined to the area of deposition of the Panagyurishte and Timok Basins and has no further continuation to the east.…”

“…The fact that the southeastern end of this linear array abuts the dextral Iskar‐Yavoritsa shear zone (which itself contains synkinematic intrusions of Late Cretaceous age) [ N. Georgiev et al , ] suggests that the linear Panagyurishte array may follow a tensional fault oriented parallel to the σ1/σ2 plane. First‐rank shear zones parallel to the WNW‐ESE trending Iskar‐Yavoritsa shear zone and NNW‐SSE tensional faults paralleling σ1 probably focused magma ascent and fluid flow to the sites of ore deposit formation, as ore deposits in the Panagyurishte segment are primarily found along these secondary oblique and cross‐arc faults [ Drew , ; Georgiev et al , ]. Relationships between fault zones and ore deposit formation are less evident in the Timok segment but may be obscured by more intense later tectonic overprint and poor exposure.…”