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We thank S.H. Büttner for the opportunity to clarify our work and the evolution we proposed for the shear zones of Sierra de Quilmes. Büttner et al. (2005) was the first comprehensive study of the Tolombon complex. Their map, photographs, and petrography were helpful and although we cited their work more than any other, we apologise that S.H. Büttner felt the work was under referenced. We have worked throughout the Tolombon complex (as first named in Toselli et al., 1978) covering much of the area described in Büttner et al. (2005) and far beyond, in numerous transects across the Sierra de Quilmes. This was the first of several papers that we aim to publish on the area and our intent was to present our data on the El Pichao shear zone (PSZ). Our next paper is on the high-grade Tolombon complex and makes full use of the comprehensive geochronology data set in Büttner et al. (2005). In Finch et al. (2015) we contend that the shear zones of the Tolombon complex are part of the same shortening event that formed the PSZ. We came to that conclusion by combining the following observations:a) W-directed movement in high-grade regions was contemporaneous with partial melting, to judge from the relationships between leucosomes and thrust planes and folds (Fig. 4d,e in Finch et al., 2015 and 4c in Büttner et al., 2005).b) W-directed movement in high-grade and low-grade rocks alike in the Divisadero region is the same as in the mylonitic rocks of PSZ (compare Fig. 6 in Büttner, 2009 with stereonets in Fig. 2 of Finch et al., 2015). From (a) and (b) we conclude movement continuity through time and space and suggested that movementon the PSZ remained constant as it cooled.c) Most significantly, we find in Divisadero and at the PSZ, thrust planes that place hotter rocks above colder rocks. We will publish a full description of the major Divisadero shear zone in our next paper. In summary, we find no support for the interpretation of Büttner et al. (2005) and Büttner (2009) of an extensional terrane. The main argument for extension in Büttner (2009) is evidence for thinning of metamorphic packages in the Migmatitic zones so that pressures recorded by the rocks are less than that indicated by the current distance between samples. Although thinned isograds are typical of extensional terranes, they alone should not be used as evidence forextension because the final distribution of isograds depends on the relative timing of paragenesis development and deformation. Furthermore, thinning of layers or metamorphic packages does not require extension. This may also occur during shortening when there is a component of shortening orthogonal or at a high angle to the isograds, bedding or foliation (pure or general shear).Numerous studies (PinÑan-Llamas, 2007; Büttner, 2009) have determined that the Tolombon complex underwent general shear, as indicated by symmetric folding with axial surfaces parallel to the shear plane. Therefore, evidence for thinning in the Tolombon complex is not inconsistent with thrusting.We hope this response provides clarity. Once again, we thank S.H. Büttner for the opportunity to clear up inconsistencies between his work and our own and we acknowledge the rich source of data and inspiration his papers have provided.