Field Guide Figure Captions
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Figure 1: Regional extent of the Independence Dike Swarm, eastern California. Dike orientations shown are representative of the dominant dike trend for each area (Moore, 1963; Rhinehart and Ross, 1964; Nelson, 1966; Chen and Moore, 1979; Karish et al., 1987; James, 1989; Davis et al., 1994). PC = Pine Creek Canyon, TP = Taboose Pass, WL = Woods Lake, AH = Alabama Hills, CR = Coso Range, AR = Argus Range, SH = Spangler Hills, GM = Granite Mountains, OM = Ord Mountains, FM = Fry Mountains, PM = Providence Mountains, ETR = Eastern Transverse Range, EM = Eagle Mountains, CM = Chuckwalla Mountains.

Figure 2: Photo and schematic illustration of sinistral oblique fabric found within a mafic Independence dike near Taboose Pass, eastern Sierra.

Figure 3: Oblique anisotropy fabric in a 3 km mafic dike in Poison Canyon, southern Argus range (STOP 3; D.A. Dinter, unpublished). Data shown are similar to that of four other traverses across the dike.

Figure 4: Strike patterns of Independence dikes for several regions north of the Garlock Fault. Dikes dominantly strike counterclockwise (¸15·) to the overall trend of the swarm (Glazner et al., in review).

Figure 5: Two proposed origins for IDS intrusion; (left) dikes intruded along tension fractures formed during extension (e.g., Chen and Moore, 1979) or, alternatively, (right) dikes may have intruded oblique fractures formed within a crustal-scale sinistral shear zone.

Figure 6: Proposed stress regime for latest Jurassic, based on field relationships found in the eastern Sierra. See Factors controlling dike injection and STOP 6 for discussion of this model.

Figure 7: Roadmap of eastern California with locations of planned stops.

Figure 8: Roadmap of area around Barstow and directions to STOP 1.

Figure 9: Geologic map of the Fry Mountains

Figure 10: Road map of area near Ridgecrest and locations of STOP 2 and 3.

Figure 11: Topographic map of Poison Canyon, southern Argus range, and location of STOP 3. The mafic dike to the west was drilled extensively for anisotropic magnetic susceptibility.

Figure 12: Roadmap of area near Aberdeen and directions to STOP 4, 5.

Figure 13: Map of the area around STOP 4, from Bradford (1995). Suggested traverse is shown by dashed line with arrows. Heavy dashed lines indicate northwest-striking diorite dikes, one of which cuts the Cretaceous(?) Spook pluton. Dikes are extremely abundant in the metamorphic rocks. Qal = Quaternary alluvium; Qb = Pleistocene basalt; Kg = granite of Goodale Mountain (92 Ma); Kad = Aberdeen mafic sill complex (92 Ma); Ksp = granite of Spook Canyon (undated, probably Cretaceous); Jtb = Jurassic quartz monzonite of Taboose Creek; Jd = quartz diorite (154 Ma: Frost and Mattinson, 1993); Jv = Jurassic(?) dacite; Pzm = Paleozoic metamorphic complex of Armstrong Canyon.

Figure 14: Sketch geologic map of the Woods Lake area, eastern Sierra, with locations of dated Cretaceous and Jurassic Independence dikes (Coleman et al., 1994, 1998).

Figure 15: Photo (oblique view) and sketch (plan view) of a mafic Independence dike in the Woods Lake area, eastern Sierra, cutting northwest-striking mylonite zones. The mafic dike is, in turn, deformed along a mylonite zone immediately to the east. We interpret this example and several others like it to indicate dike intrusion occurred closely in time with mylonitization (Carl et al., 1996a; STOP 6).

Figure 16: Equal-area stereonet plot of poles to mylonitic foliations measured in the Woods Lake area, eastern Sierra. The mylonite zones dominantly strike north-south and dip moderately eastward.

Figure 17: A mafic dike in Woods Lake area, eastern Sierra, may have filled conjugate fractures. Oblique foliations differ in northwest- and northeast-striking portions of the dikes which we interpret to have formed when the dikes opened obliquely to their margins.

Figure 18: Photomicrographs of (top) the undeformed portion of a 148±1 Ma Jurassic mafic dike (WL95-19) and (bottom) 94±1 Ma Cretaceous mafic dike (WLT94-10) in the Woods Lake area (see Fig. 14 for sample locations); U-Pb zircon age data from Coleman et al. (1998).
Figure 19: Foliation observed in dated Cretaceous mafic dike in the Woods Lake area, eastern Sierra (WLT94-10; see Fig. 14 for sample location). Compare with Fig. 2.
Figure 20: Roadmap of Alabama Hills northwest of Lone Pine and location of STOP 7.