B1: L-VERSES S-TECTONITE FABRIC VARIATIONS WITHIN THE SOUTHERN ADIRONDACK SHEAR ZONE SYSTEM: PROGRESSIVE DEFORMATION ASSOCIATED WITH A SINISTRAL CONJUGATE TO A GRENVILLE SYNTAXIS
David W. Valentino, Dept. of Earth Sciences, SUNY Oswego, Oswego, NY 13126
Gary S. Solar, Dept. of Earth Sciences, SUNY Buffalo, Buffalo, NY 14222
Jeffrey R. Chiarenzelli, Dept. of Geology, SUNY Potsdam, Potsdam, NY 13676
Alexander E. Gates, Dept. of Geological Sciences, Rutgers University, Newark, NJ 07102
Paul Freyer, Dept. of Earth Sciences, SUNY Oswego, Oswego, NY 13126
Rachel E. Price, Dept. of Geological Sciences, Rutgers University, Newark, NJ 07102
INTRODUCTION
This field guide was prepared in tandem with a field guide for the 73th and 75th NYSGA field conferences, and synchronously with an article written for the Memorial Volume to Nicholas Rast, recently published in the Journal of Geodynamics (Gates et al., 2004). Therefore, some parts of this guide are directly related to work presented in the earlier field guides and some parts were prepared for multiple projects; however, the emphasis here is exclusively on new findings in the Adirondacks. We encourage the reader to examine our data presented in the earlier field guides (Gates et al., 2001; Gorring et al., 2003) and summarized in Gates et al. (2004) for further details.
Transpressional strain is found to be related to a variety of tectonic environments. Transcurrent faults with restraining bends produce structures such as thrusts and conjugate faults (Woodcock, 1986). Oblique motion vectors between two tectonic plates result in oblique collision that produces zones of transpressional strike-slip deformation in the hinterland, and belts of thrusting in the foreland (e.g., Woodcock, 1986; Tappionier and Molnar, 1976). As well, zones of transcurrent strain can develop syntaxes in regions of the crust experiencing horizontal escape as the result of rigid indentors in the colliding lithosphere (Tappionier and Molnar, 1977). These structures have been almost exclusively described for rocks that were exhumed from intermediate to shallow levels of the crust. The distribution of strain and the location of faults can be controlled by the presence of pre-existing structures (Dewey and Burke, 1973), or by the juxtaposition of rock bodies with ductility contrasts such as decoupling of cover rocks over deforming crystalline basement (Gates et al., 1999; Valentino et al., 2004).
Dewey and Burke (1973) and Windley (1986) proposed a model for tectonism recorded in the Grenville Province rocks based upon the deep structure of Himalayas and the intensity of tectonism recorded there. Tapponnier and Molnar (1977) proposed that the rigid indentation of India formed a syntaxis (abrupt bend in the general attitude of the orogen) containing conjugate strike-slip faults in the Eurasian continent during the Himalayan Orogeny. Northeast-striking sinistral, transcurrent shear systems accommodate tectonic escape (Tapponnier et al., 1982) in China and southeast Asia, and these fault systems record hundreds to thousands of kilometers of offset over tens of millions of years. There are also smaller, northwest-striking, dextral systems that have been synchronously active with the sinistral zones that form the conjugate pairs to the larger sinistral zones of tectonic escape within the Himalayan syntaxis.
The Grenville Province forms one of the longest and most deeply exhumed areas of continental crust on Earth, extending from Scandinavia, through eastern Canada and inliers in the Appalachian chain, to Texas and Mexico, and perhaps beyond. Grenvillian basement massifs in the northeastern United States form a series of unconnected inliers along the Appalachian orogen (Figure 1). Because of the great spacing and high degree of tectonism associated with the Appalachian tectonic events, correlation of Grenvillian rocks among the massifs are difficult. In addition to widespread granulite-facies metamorphic conditions at about 1.0 Ga, these basement massifs all contain vast volumes of 'A-type' granite bodies whose magma had intruded (ca. 1150 Ma) into older supracrustal rocks (ca. 1250 Ma) of varied character prior to Ottawan deformation (ca. 1040 Ma; e.g., McLelland and Isachsen, 1986). The Grenville Province exposes the deep crustal roots of an ancient mountain range of immense portions, and records the assembly of one of the Earth's few recognized supercontinents, Rodinia. Consequently the Ottawan Orogeny (ca. 1070-1000 Ma) is often cited as a classic example of continent-continent collision and compressive thickening of the crust, with invocation of the Himalayas as a modern tectonic reference frame (Dewey and Burke, 1973; Windley, 1986; McLelland et al. 2001). However, refinement and testing of such a model must address many important components of the orogeny. One of the most significant components in the Himalayas is the massive amount of strike-slip faulting expressed in tectonic escape and the syntaxis (Tapponnier and Molnar, 1977). Whereas compressive tectonics is universally documented in the Grenville orogen, few workers have recognized analogous, large-scale, orogen-parallel deformation (cf. Baer, 1977). Some of the evidence for strike-parallel deformation is described herein, and is much of the basis for the sequence of outcrops listed in this guide.

B1: L-VERSES S-TECTONITE FABRIC VARIATIONS WITHIN THE SOUTHERN ADIRONDACK SHEAR ZONE SYSTEM: PROGRESSIVE DEFORMATION ASSOCIATED WITH A SINISTRAL CONJUGATE TO A GRENVILLE SYNTAXIS
D.W.Valentino, G.S.Solar, J.R.Chiarenzelli, A.E.Gates, P.Freyer, R.E.Price

STOP 1. Calc-silicate gneiss on the north side of the Snowy Mountain Dome (SMD).
Turn left into the overlook parking lot, and walk south on Rt. 30 approximately 0.2 miles to the first roadcut on the west (right) side of the road.
Calc-silicate gneiss with penetrative foliation and folds occurs in outcrops on the west side of Route 30. The foliation is defined by planar aggregates of recrystallized plagioclase, quartz and diopside (Figure 13). Locally the calc-silicate gneiss contains quartzofeldspathic layers that define isoclinal folds, and locally there are recrystallized masses of diopside (some 10 cm in diameter).
The dominant foliation in the outcrop in most places is structurally continuous with penetrative foliation (S2) in the Snowy Mountain dome, and dips moderately northward at this location. Portions of the exposure reveal an earlier foliation (S1) preserved mostly in the hinges of the isoclinal folds (F2) (Figure 13). The S1 foliation does not occur in the rocks of the Snowy Mountain suite, and the S2 foliation dies out away from the Snowy Mountain dome. In a relative sense, the S1 foliation either predates or is synchronous with the intrusion of the Snowy Mountain suite, and the S2 foliation is superimposed on the suite.
D.W.Valentino, G.S.Solar, J.R.Chiarenzelli, A.E.Gates, P.Freyer, R.E.Price

Roadcuts of charnockitic gneiss.
D.W.Valentino, G.S.Solar, J.R.Chiarenzelli, A.E.Gates, P.Freyer, R.E.Price

STOP 2: Charnockitic gneiss on the north side of the SMD.
Park on the right side of Rt. 30 and cross the road to the roadcut on the east (left) side (at the "Southwinds" sign).
The contact between the calc-silicate gneiss of STOP 1 and charnockitic gneiss of the Snowy Mountain suite occurs approximately 1 km northeast of this location, and is concordant with the S2 foliation. Here there is exposure of highly deformed charnockitic gneiss on both sides of the road. The foliation (S2) is defined by planar aggregates of dynamically recrystallized plagioclase and broken grains of hypersthene and augite. The foliation dips moderately northeastward and weak mineral lineations trend shallowly toward the east. Many of the outcrop surfaces reveal augen of plagioclase with core-mantle structure. Dynamically recrystallized tails developed on porphyroclasts of plagioclase merge with the penetrative foliation. The plagioclase augen are interpreted to be relict igneous crystals, possibly original megacrysts. When viewed on outcrop surfaces that are parallel to the lineation and perpendicular to the foliation, the augen appear to be asymmetric defining both σ- and β-porphyroclasts. Additionally, domino structures and Type I S-C fabrics can be viewed on some optimum surfaces. The kinematic indicators are consistent with top toward to the west ductile shearing, or low-angle sinistral considering the shallow plunge of the lineations.
Proceeding south across the Snowy Mountain dome, the penetrative foliation in the charnockitic gneiss progressively dips toward the east and then toward the southeast. There are numerous outcrops along Route 30 that can easily be viewed. Where the southeastern spur of Squaw Mountain intersects Route 30, there is exposure of gabbroic gneiss and megacrystic anorthosite. We will not be stopping at this outcrop during this trip due to time constraints. However, this is a good place to view the transitional compositions and deformation fabrics. The megacrystic anorthosite lacks penetrative deformation at this location, but some parts of the outcrop contain dynamically recrystallized anorthosite with well developed S2 foliation. The gabbroic gneiss contains penetrative foliation and well developed lineations at this location.
The transition from gabbroic- to charnockitic-gneiss occurs approximately 1000 meters northeast along the Squaw Mountain spur. This transition was documented by DeWaard and Romey (1969). Within the charnockitic gneiss branching high-strain zones can be seen (Figure 14). In places, the high-strain zones merge and have tapered terminations, and close inspection will reveal the penetrative foliation. Compositionally, the rocks in the high-strain zones are identical to the bounding charnockitic gneiss, except for the occurrence of minor quartz veins. The high-strain zones have the same general strike as the location foliation, but typically dip steeper northward in this area. Mineral lineations are better developed in the high-strain zones. Shear sense indicators are consistent with the shear sense indicators observed in the charnockitic gneiss with top toward the west ductile flow, or low-angle sinistral. The high-strain zones contain the same metamorphic minerals as the lower-strain charnockitic gneiss.

Roadcuts of metanorthosite.
Roadcuts of gabbroic metanorthosite and megacrystic metanorthosite.

STOP 3: "Underview" of the Snowy Mountain Dome
From this location, the entire structure of the Snowy Mountain dome can be viewed. Numerous slide faces expose the shallowly dipping foliation that occurs at the top of the dome (Figure 15). The exposures at the top of Snowy Mountain can be accessed by a popular hiking trail that occurs about 2 km north of this location. The top of Snowy Mountain is underlain by gabbroic gneiss with penetrative S2 foliation. The foliation dips shallowly toward the north and sub-horizontal mineral lineations trend nearly due east. A near vertical outcrop near the top of the mountain reveals abundant shear sense fabrics. Detailed kinematic analysis using porphyroclasts, S-C fabrics and shear bands resulted in dominant shear of top toward the west. However, some domains upward of a few meters thick showed conflicting shear sense of top toward the east. These exposures are the structurally highest part of the dome.

STOP 4: Charnockitic gneiss on the SE side of the Snowy Mountain Dome.
Turn right onto access road for campsites. Drive this road until just into the woods, and park in the wide flat area just before the bridge over Falls Brook. Walk across the bridge and past the metal gate, then plunge into the woods on the right of the access road about 10 meters to the outcrops in the brook that form the falls.
Stop 4 is of highly deformed charnockitic gneiss, the same lithology as Stop 2. However, the penetrative foliation dips moderately toward the southeast due to the position on the Snowy Mountain dome. At this location, and as before, the foliation (S2) is defined by planar aggregates of dynamically recrystallized plagioclase and broken grains of hypersthene and augite, and weak mineral lineations trend shallowly toward the east. Augen of plagioclase have dynamically recrystallized tails, often forming asymmetric kinematic indicators. As well, Type I S-C fabrics are well developed in some domains (Figure 16). Unlike Stop 2, the shear sense determined at this location is top toward the east. But, considering the dip is southerly, and mineral lineations trend easterly, the shear sense can be considered low-angle sinistral.

Jessup River

Roadcuts of quartzo-feldspathic gneiss with granite dikes
Roadcuts of quartzo-feldspathic gneiss with granite dikes on both sides of the road.

Calcite-garnet rock on right, rock painted as a pig on the left.
Roadcut of calcite-garnet rock on the right, with a rock painted as a pig on the left.

Roadcut of steeply-dipping dextrally sheared rocks on the right.

STOP 5A. Garnet amphibolite, calc-silicate rock and quartzo-feldspathic gneiss.
Here, these three rock types and their contacts are seen. The northern portion of the outcrop consists of garnet amphibolite, the next section of the outcrop is calc-silicate rock and the southern portion is fine-grained quartzofeldspathic gneiss. Complex sheath folds with sub-horizontal tight, isoclinal and sheath folds of foliation and compositional layers dominate the rock, particularly in the gneiss (trend to 110°) (Figure 17). Excellent views of the folds are seen on top of the southern part of the outcrop. The contacts between the rock types are also folded in similar fashion. Matrix minerals define lineations that are E-W and subhorizontal, but are variable in orientation due to folding.

STOP 5B. Garnet amphibolite and quartzo-feldspathic gneiss.
Park on the right, just after the guard rail, as you ascend the north slope of Burgess Hill (see location map). The outcrop is a roadcut on the east (opposite) side ofRt. 30 just north of the sign for Lake Pleasant.
Here the garnet amphibolite and garnet-bearing quartzo-feldspathic rock are in sheared contact. The amphibolite has a distinct foliation and lineation that is folded into shallowly inclined tight folds (N dipping axial planes) whose axes are shallowly E-W plunging. The lineation in the amphibolite is shallowly plunging to 112°. The fabric in the quartzo-feldspathic rock is distinct in contrast to the amphibolite, showing a penetrative L>>S tectonite fabric whose lineation plunges shallowly to 112°. The L>>S fabric is defined by both rods of quartz and quartz aggregates, and by tails around garnet. The highly fractured nature of the outcrop offers excellent views of this fabric. The contact between the rock types is distinct due to the color difference, but also because the amphibolite is boudinaged (foliation boudinage) due to apparent contact-parallel shear. The interboudin partitions are in-filled by plagioclase and amphibole (Figure 17).

Top of the hill (garnet amphibolite roadcuts on both sides).

STOP 5C: Overlook of Speculator Mountain, and the PLSZ.
Park on the right side of the road just south of the intersection, and walk to the top of the large roadcut for southerly views of Lake Pleasant and Speculator Mountain, and the PLSZ.
The rock here is sub-horizontally stratified, with the rock at the top of the hill to the north (garnet amphibolite) the lowest stratum, and the base of the outcrop is interlayered amphibolite and granitic gneiss, followed by granitic gneiss with mica 'mats' at the top (at the viewing area). Foliation is subhorizontal here, but, again, the mineral lineation is shallowly E- and W-plunging. The view to Speculator Mountain illustrates the structure of the late history of the PLSZ. The bench on the east side of the mountain is the top of the hanging wall block of a moderately W -dipping normal fault, and the peak of Speculator Mountain is the hanging wall block. This normal fault is defined by fabric with a distinct top-down fabric trajectory (see Figure 10), and defines the zone to be about 100 m thick. This is one of many normal shear zones that cut the E-W fabric that defines the PLSZ, but this one is perhaps the thickest. Most identified are a few centimeters thick (as in Figure 10).

STOP 6: L-S and L>S fabrics in the PLSZ.
The Piseco Lake shear zone is developed in rocks of granitic composition. Dynamically recrystallized feldspars and quartz form spectacular ribbon- and rod-shaped mineral lineations (McLelland, 1984), in addition to mafic phases such as biotite, chlorite and accessory magnetite. In many places, the alignment of ribbons forms the foliation in this outcrop (Figure 18). Individual quartz ribbons have aspect ratios upward of 60: 1. The foliation dips gently southward and the lineations trend about 110°(Figure 18). This location occurs on the southern flank of the map-scale antiform defined by the foliation in the Piseco Lake shear zone. At the western end of the outcrop there are rods of amphibolite (10-30 cm diameter) within the granitic gneiss. In the granitic gneiss, both biotite and chlorite blades form microscopic lineations and foliation parallel to the macroscopic structure. Rare grains of hypersthene have been found, but they always have well developed overgrowth textures that include biotite and chlorite. The biotite and chlorite are the most abundant index minerals in the granitic gneiss, and suggest the deformation was last active under low-grade metamorphic conditions, although probably began at much higher conditions to account for the relict grains of hypersthene.

TOP 7: Shear fabrics of the southern PLSZ.
Park as far off the road as possible. The outcrop for Stop 7 is pavement exposures located within the bed and the gutter on the east side of the road.
This stop consists of a sub-continuous series of pavement exposures located in the road bed, and in the gutter on the east (northeast-bound) side of the road. Due to the nature of this location, the extent of the exposed rock at this stop changes daily, so some or all of the rock described here may be viewable depending upon the time of the season in which the stop is visited (best later in the season).
Here, quartzo-feldspathic gneiss has intense shallowly WSW-plunging lineation and steeply S dipping foliation, both defined by ribbons (generally 1-5 cm long depending upon grain size). Locally, the gneiss has layers (up to 50 cm wide) of coarser-grained fabrics (grains up to 1 cm in diameter). Within the gneiss is lens- to block-shaped, and blunt-ended amphibolite bodies, also with a distinct mineral fabric that is sub-parallel to that of the gneiss. In general, the long dimension of lens-shaped amphibolite bodies are sub-parallel to the host gneiss fabric. The lengths of these bodies are not quantified due to the fact that the outcrop is composed of meter-scale windows through road gravel, but short dimensions are usually exposed showing bodies 10 to 30 cm wide. Fabric in the amphibolite is generally terminated at the boundary of the body, whereas the fabric in the quartzo-feldspathic gneiss drape the amphibolite bodies, showing fabric tails at the blunt ends of the bodies, sub-parallel to the mineral lineation (as porphyroclasts draped by matrix minerals; Figure 19).

STOP 8: Variations of L-S, L>S and L»S fabrics of the PLSZ.
Park along the side of the road in "the notch" between East and West Notch Mountains (see location map). The notch is Stop 8, featuring 0.2 miles of continuous exposure on both sides of Powley Road. The exposure on the northwest side (left) is the subject of the stop.
Due to the continuous nature of the exposure in an across-strike direction, the fabrics within the quartzo-feldspathic gneiss may be examined for their variations at about the meter scale. In general, the rock fabrics vary between L-S to L»S tectonite. Foliation intensity is variable, but mostly weak here. Foliation dip varies greatly across strike (moderately to steeply south-dipping), whereas the intensity and orientation of the lineation is consistently sub-horizontally E- and ESE-plunging. Of particular note in this outcrop, in addition to the matrix fabrics, is the pervasive feldspar porphyroclasts. Fabrics drape the porphyroclasts to form tails that are elongate sub-parallel to the matrix mineral lineation (sub-horizontal). Perhaps the cleanest views of the fabrics along the lineation may be seen at the very end (northeast end) of the exposure. We suggest that it is best to leave this spot for last in order to best appreciate the nature of the fabric in these rocks.

STOP 9: Fabric variations in gneiss in the PLSZ
Park along the side of the road avoiding the blind curve. The outcrops for Stop 9 are along the side and gutter of the northwest side of the road just before and at the left-hand curve in the road.
Fabric variations in garnet-bearing quartzo-feldspathic gneiss in the PLSZ. Here the quartzo-feldspathic gneiss fabrics vary from LS to L»S tectonite, whose lineation is shallowly E- to ESE-plunging, and the relatively weak foliation is moderately to steeply S-dipping. Feldspar porphyroclasts are present as at Stop 8. The southwest end of the exposure shows a high density of garnet porphyroclasts within foliation. Locally, garnet is concentrated into 2-3 cm-wide bladed bands, or is apparently flattened. Also locally, garnet occurs in patches or 'clots' 3-5 cm wide and up to 20 cm long.

STOP 10: Mylonitic augen gneiss of the PLSZ.
Park on the side of the road for a set of small low pavement exposures on the left (northwest) side of the road as the top of the hill is approached.
Best views of the fabrics in the quartzo-feldspathic gneiss are seen in the approximately 1.5 meter-long, beautifully polished pavement at the top of the hill. Here the rock has meter-scale mineralogical layers where the northern part is relatively more leucocratic, dominated by feldspar (up to 1 cm wide) and quartz ribbons (up to 3 mm wide). The fabric is intensely strong L-S tectonite throughout the exposure, with a steeply S-dipping foliation, and a sub-horizontal shallowly E-plunging lineation. The fabric may be considered 'textbook' mylonite, with spectacularly grain-size reduced texture in the less leucocratic layer. The mylonitic fabric transects the sharp contact between mineralogical layers at a low angle where it transitions into a more ribbon texture in the leucocratic layer. Of particular note here, besides the intense matrix fabrics, is the penetrative augen (generally 1 to 4 cm long) composed exclusively of aggregates of millimeter-grain-size quartz + feldspar, not single crystals. In every case, augen are draped by the matrix fabric, elongate sub-parallel to the lineation. There are a few much larger of these augen in this rock composed of rounded single feldspar crystals (up to 4 cm long) that are surrounded by aggregate quartz and feldspar (Figure 20).

STOP 11. Ultramylonite of the PLSZ.
Park on the side of the road to view the two small pavement exposures in the bed of the road for Stop 11.
These outcrops are very small (about 1 m or so long each) and isolated, so whether or not these rocks are viewable depends upon many factors including whether or not the road has been re-graded recently. As with STOP 7, the exposure of these rocks is better later in the season. The quartzo-feldspathic gneiss here shows spectacular mylonitic fabrics, as at Stop 10, where foliation and lineation are penetratively parallel across the small exposures (E-W fabrics with steep south dips and sub-horizontal E-plunges). Centimeter-scale textural layers are the highlight of this exposure where 1 to 5 cm wide bands of quartz + feldspar aggregate. Relatively thin layers of these aggregates are seen 'pinched and swelled' lenses. Individual augen of the aggregate are in the less leucocratic layers. We envision these textural variations to illustrate a progression of mylonitization where larger bands progressively become augen. Further, we suggest that the augen are seen kinematically combined, and as they interfered, they may form new aggregate bands. In a manner of speaking, one could say that the fabrics in this rock are snapshots of the progression, and that this rock is mylonite that has been multiply reworked as deformation continued.

STOP 12: L-S tectonite of the PLSZ.
Park on the right side of the road for the road cuts just over the top of the hill.
The quartzo-feldspathic gneiss here is spectacular L-S tectonite, whose foliation is moderately SSW-dipping, and whose lineation is shallowly W-plunging. As at Stop 10, augens are aggregates of fine-grained feldspar + quartz, and some here have asymmetric delta tails that show sinistral offset (see Figure 9B). Pavement outcrop at the top of the western roadcut show excellent three-dimensional views of the fabric.

STOP 13A: East of the gorge.
Turn left onto Gray Wilmurt Road just after a sharp right-hand curve in Rt. 8. Cross a bridge over the West Canada Creek and park at the intersection with Jones Road. Walk back toward the bridge over West Canada Creek and down the hill to the outcrop just east (upstream) of the bridge (see location map). The outcrop forms a small water fall on the creek.
The Piseco Lake shear zone traces westward through the West Canada Creek basin. Some of the best continuous exposures occur in the Ohio Gorge near Wulmurt. The last stops for this field trip are in highly deformed granitic gneiss in the gorge. During periods of high water, the exposures at the eastern and western end of the gorge may be covered or not easily accessed. Permission is needed from the landowner at Stop 13A.
The West Canada Creek forms a small waterfall at the upstream part of this outcrop. Pavement exposures reveal the L-S and LS deformation fabric in granitic gneiss (Figure 21). Foliation is gently dipping and the lineations are subhorizontal. In the region immediately down-stream of the falls, the foliation is defined by planar aggregates of recrystallized K-feldspar and quartz that alternate with dark layers containing abundant chlorite and minor biotite. The dominant fabrics are cross cut by at least three small high-strain zones. Two are steeply dipping and strike about east-west, and the third strikes south and dips moderately westward. One of the steeply dipping high-strain zones occurs in the vertical face at the southern side of the outcrop. Another occurs at the western limit of the outcrop close to the water. The north-south striking zone occurs in the low ledge near the falls. This small shear zone contains deformed pegmatite, and cross cuts the PLSZ foliation and lineation (Figure 10). Shear sense is top down to the west or normal. The other high strain zones both contain evidence for oblique sinistral shear.

STOP 13B: Western limit of the outcrop belt in the Ohio Gorge.
Park on the right shoulder just after a steep downhill drive. Walk upstream along West Canada Creek to the first bedrock exposures for the westernmost outcrops in the Ohio Gorge, and Stop 13B.
At this location the north dipping foliation of the Piseco antiform can be viewed in addition to the typical variation in L-S and LS fabrics at the outcrop scale. Again, the foliation is defined by planar aggregates of dynamically recrystallized feldspars and quartz. Quartz also occurs in greatly attenuated ribbons, as seen at other locations during this field trip. Of particular interest at this location, are abundant kinematic indicators that are easily observed. Outcrop surfaces that are perpendicular to the foliation and parallel to the lineation reveal asymmetric augen of K-feldspar and plagioclase forming both σ- and β-type shear sense indicators with most showing top toward the west displacement (Figure 9A). Since the mineral lineations are subhorizontal, the shear sense is considered to be low-angle sinistral at this location. The abundant large (cm-size) porphyroclasts of feldspar provide some information about the protolith for the PLSZ rocks in this region. The relict grains are most likely the remains of megacrysts from an original granite.