1. The Cullowhee Olistostromal Terrane

2. Blue Ridge Ultramafic Bodies
Lake Chatuge

3. Ultramafic Rock Occurrences in Subduction/Collisional Belts
--Ophiolite Complexes
--Blocks in Accretionary
Complexes
--Forearc Serpentinites

4. REU Site Research Program, 1997-2001
48 Undergraduate Participants over 4 years
Students conducted Field mapping, Petrography, Whole-rock and mineral chemistry and field geophysics
Post-Summer student efforts in petrography, mineral chemistry and geochemistry

5. Field Relations of the Buck Creek and Carroll Knob Mafic/Ultramafic Complexes
MG: Mica Gneiss
PX: Meta-Pyroxenite
PGA: Pale Green Amphibolite
AM: Amphibolite
DN: Dunite
TC: Coronal
Metatroctolite
EMS: Edenite-
Margarite Schist
DNA: Altered Dunite

6. Geochemistry of the Buck Creek and Carroll Knob Mafic/Ultramafic Complexes
Geochemically consistent with mafic and ultramafic cumulate protoliths

7. Rare-Earth Element Systematics of Buck Creek Compared to Lake Chatuge and Carroll Knob
Amphibolites
(meta-gabbros)
Light rare-earth depleted, MORB-like patterns

8. NE Cullowhee Terrane Ultramafic Bodies: Field Relations
Deformed Amphibolite Block
in metasedimentary gneiss,
Tatham’s Creek, NC
Field Relations of Mafic and
Ultramafic rock units near
Addie, NC. (REU 2001)
--Yellow: amphibolites
--Green: Ultramafic rocks
Amphibolite/ultramafic
Outcrops range from
map-scale,lenticular bodies to small lenses in the mica gneiss country rocks.

9. Webster-Addie Ultramafic Body: Structure and Deformation
The Webster-Addie body includes Pyroxenite lenses, often altered to tremolite+talc, which define the local foliation. These lenses/layers may represent deformed pyroxene pods, or original pyroxenite layers.
Orthopyroxene/Talc-Tremolite schist layers showing boudinage: Chestnut Gap quarry, NC

10. Geochemistry of the Webster-Addie and Balsam Gap Ultramafic Bodies
Amphibolites
Chemically, the mafic and ultramafic rocks from Addie and Balsam are not consistent with a related cumulate assemblage. The Amphibolites are andesitic in composition.

11. REE Comparison: NE ultramafics to the Buck Creek complex
Isotopic Characteristics:
Nd of Buck Creek and
Lake Chatuge: ~+5
Nd of Webster-Addie: ~-1
(Shaw and Wasserburg, 1984)
Webster-Addie has
higher initial Sm/Nd than Buck Creek.

12. Metasomatic Effects: Webster-Addie Ultramafic Complex
Extensive dike intrusions and associated hydrothermal veining are typical in the Webster-Addie complex

13. Implications of Blue Ridge Ultramafic Rock Units:
SW Cullowhee Terrane: Buck Creek, Carroll Knob, Lake Chatuge
--a fragmented Ophiolite Complex?
NE Cullowhee Terrane:
--Lenticular Mafic and Ultramafic bodies
--No clear cumulate characteristics
--no petrogenetic links evident between ultramafic and mafic rocks
--Suggestions of metasomatic alteration

14. Implications of Blue Ridge Ultramafic Rock Units:
Cullowhee Terrane: “Enigmatic” (Raymond et al. 1989)
Possibly:
--SW Cullowhee Terrane: A suture-zone assemblage, w/ the Hayesville Fault as the old suture.
--NE Cullowhee Terrane: extenstion of “Melange” rocks of the Ashe Metamorphic Suite, or a different structural unit within a paleo-accretionary complex.
To Test:
--Detailed Field Relations of mafic/ultramafic units
--Geochemical comparisons of amphibolites, and ultramafic bodies from Franklin, NC northeastward - do they have similar protoliths?