Diorite-pegmatite mixing, Serrapilheira

There are two outcrops that show unusual hybridization relationships between pegmatite intrusions and diorites causing hybridization of both: NE26 and NE28.

NE26 outcrop with several facies of intrusive rocks from a fine mafic diorite >3m wide, medium granite with smal Kfs phenocrysts, blocks of diatexite 3 x 3 m inside fine, grey homogeneous Bt granite with well-defined foliation. -8.72416 -36.76608.

Figure 1a) NE26. Pegmatite intruding diorite and hybridizing.
Figure 1b) NE26. Detail of (a), irregular boundary between pegmatite and diorite with transfer of pegmatitic biotite and K-feldspar to the diorite.

Figure 1c) NE26. Detail of (a) where hybridization gives rise to a heterogeneous diorite..
Figure 1d) NE26. Mantled K-feldspar transferred from the pegmatite into the diorite.

Figure 1e) NE26. Irregular dykelets in diorite coming from a pegmatite intrusion.
Figure 1f) NE26. Hybrids.

Figure 1g) NE26. Pegmatitic K-feldspar in diorite.
Figure 1g) NE26. Strain shadow filled in by felsic magmatic segregation around a mimgatite xenolith in granite. This is a result of magma solidification and segregation of the felsic magma into the strain shadow.

Figure 1h) NE28. Pegmatite intrusion hybridizing diorite
Figure 1i) NE28. Pegmatite intrusion hybridizing diorite.

Figure 1j) NE28. Pegmatite intrusion hybridizing diorite
Figure 1k) NE28. Pegmatite intrusion hybridizing diorite.

Figure 1j) NE28. Intrusion of a composite dyke into diorite. Dyke has an outer margin of felsic, coarse grained granite which is in irregular contact with a more mafic granitoid that is heterogeneous and plucks K-feldspar grains from the irregular contact. One interpretation is that this heterogeneous granitoid is a diorite more thoroughly hybridized with granitic-pegmatitic magmas.

Disaggregation and assimilation of a migmatite by intrusion of pink granite: mingling of two mushes? Outcrop NE08 between Cruzeiro and Sertania along the road. -8.32522 -37.27190 553m. This is a sequence of gneiss and amphibolite that was undergoing partial melting as evidenced by leucosomes with peritectic, coarser hornblende, resulting from the influx of water. This migmatitic sequence was disrupted and assimilated by an intrusive pink granite. The relationships suggest fluidity of the migmatite at the time of granite intrusion. The intensity of the assimilation process is revealed by final product where only schlieren of the coarser peritectic hornblende grains are left within the granite as they are pulled away from the migmatite.

Figure 2a) .	Figure 2b).
Figure 2c) .	Figure 2d).
Figure 2e) .	Figure 2f) Note irregular lighter patches within the homogeneous granite that are linked to the contact with the amphibolite/gneiss block.

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Figure 1a) NE26. Pegmatite intruding diorite and hybridizing.	Figure 1b) NE26. Detail of (a), irregular boundary between pegmatite and diorite with transfer of pegmatitic biotite and K-feldspar to the diorite.
Figure 1c) NE26. Detail of (a) where hybridization gives rise to a heterogeneous diorite..	Figure 1d) NE26. Mantled K-feldspar transferred from the pegmatite into the diorite.
Figure 1e) NE26. Irregular dykelets in diorite coming from a pegmatite intrusion.	Figure 1f) NE26. Hybrids.
Figure 1g) NE26. Pegmatitic K-feldspar in diorite.	Figure 1g) NE26. Strain shadow filled in by felsic magmatic segregation around a mimgatite xenolith in granite. This is a result of magma solidification and segregation of the felsic magma into the strain shadow.
Figure 1h) NE28. Pegmatite intrusion hybridizing diorite	Figure 1i) NE28. Pegmatite intrusion hybridizing diorite.
Figure 1j) NE28. Pegmatite intrusion hybridizing diorite	Figure 1k) NE28. Pegmatite intrusion hybridizing diorite.

Diorite-pegmatite mixing, Borborema Province