10 cm. 5 cm. 10 cm. glacial striae. glacial striae

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Collin Walsh
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$te how the vein refracts across a quartzitic layer of relative higher competence.$ $Leucocratic vein refracted across layered metavocanites and a distinct boudinaged competent calc-silicate layer.$

1 GSA DATA REPOSITORY Druguet et al. Supplementary Photographs All photographs are vertical shots of sub-horizontal outcrops. All contacts are sub-vertical except for DR7 (dips indicated on picture). quartzitic layer Figure DR1. Leucocratic vein cutting across heterogeneous schists. te how the vein refracts across a quartzitic layer of relative higher competence. The vein suffered little or no deformation, as indicated by the absence of both, buckle folds and associated deflectional structures in the host. S D glacial striae calc-silicate layer glacial striae Q S Figure DR2. Leucocratic vein refracted across layered metavocanites and a distinct boudinaged competent calc-silicate layer. te the incipient folding of the vein segment on the left of the coin. Figure DR3. Leucogranite vein cutting across heterogeneous host rocks. S = schists; Q = quartz-rich layers; D = diorite dike (early intrusion). Relative competence: D>Q>S. te the sharp jogs of the vein within and at the margins of the diorite, indicative of intrusion refraction.

2 coarse-grained granitoid fine-grained mafic dike Figure DR4. Stepped aplite vein developed by intrusion refraction as the vein cuts across relatively competent granitoid and incompetent mafic dike. metadiabase banded metavolcanic rocks metadiabase Figure DR5. Leucogranite vein across banded metavolcanic rocks and more competent metadiabase lenses. Main deflections are attributed to intrusion refraction, although some minor folds seem to be developed along the vein where it is hosted by banded metavolcanic rocks.

3 banded metavolcanic rocks massive amphibolite (metagabbro) Figure DR6. Intrusion refraction of leucocratic veins across the contact between massive amphibolite (competent) and banded metavolcanic rocks (alternating competent and incompetent layers). te the zigzagging shape of veins in the banded metavolcanics, compared to their more planar shape in the massive amphibolite. Also notice the likely superposed, dextral slip along the main interface between host rocks.

4 63 Tur-rich rims Tur-rich rim 70 Tur-rich rims Figure DR7. Irregular contorted pegmatite dikes cutting across metapelitic and metapsammitic host rocks. Left: general view. Right: detail photograph of the dike marked with a dashed box. te the sharp intrusive jogs, well preserved where the dikes crosscut the darker metapelitic layers. This is due to the presence of strong tourmaline(tur)-rich rims developed along the vein margins in contact with the metapelitic schists. In contrast, ptygmatic folds are present in the vein segments hosted by incompetent layers (untourmalinized schists). Mas de la Birba zone in the Variscan Cap de Creus belt (NE Spain).

5 Sharp jogs or deflections DIKE (or VEIN) across heterogeneous and/or anisotropic rocks Sinusoidal deflections n-matching dike walls Is the original fracture restorable by matching the dike walls? 3 Dike is deformed 3 Initial non-planar geometry 3 Dike is not deformed DR1, upper part of DR3, DR4, part of DR7 3 Dike has superposed deformation DR5 l Likely initial non-planar geometry Are there any deflectional (cuspate/fanning) structures in the adjacent host rocks? 3 Dike is little or not deformed DR2, lower part of DR3, DR6 l Dike could be initially non-planar 3 Primary structures are transposed part of DR7 Are there any deflectional (cuspate/fanning) structures in the adjacent host rocks? l Dike was likely planar initially 3 Dike is deformed in a small amount Figure DR8. Interpretation of Figures DR1 to DR7 according to the schematic flow chart of Druguet et al. (Fig. 5).

lecture 7 Foliations & lineations

Kristallingeologie lecture 7 Foliations & lineations 28 participants Results test A, 2008 Maximum 70 points Pass!35 points (!50%) Best result 67 points Average result 54 points ("2.3) Worst result 30 points