Date File Created	Name of Creator
7/24/09	Sheryl Singerling
GeoRef Data	2007-075911
DN	GeoRef
TI	"Thermal evolution and exhumation of deep-level batholithic exposures,southernmost Sierra Nevada, California"
AU	"Saleeby, J; Farley, K A; Kistler, R W; Fleck, R J"
AF	"California Institute of Technology, Division of Geological andPlanetary Sciences, Pasadena, CA, United States (USA)"
AF	"University of Oklahoma, United States (USA); Stanford University,United States (USA); National Museum of Natural History, United States(USA); U. S. Geological Survey, United States (USA)"
MT	Convergent margin terranes and associated regions; a tribute to W. G.Ernst
ED	"Cloos, M; Carlson, W D; Gilbert, M C; Liou, Juhn G; Sorensen, S S"
AF	"University of Texas at Austin, Geological Sciences Department, Austin,TX, United States (USA)"
CF	"Geological Society of America, 2003 annual meeting, symposium on Phaserelations, high P-T-ometry, and plate pushing, Seattle, WA, UnitedStates, Nov. 2-5, 2003"
SP	"USGSOP, Non-USGS publications with USGS authors"
SO	"Special Paper - Geological Society of America, vol.419, pp.39-66,2007"
IS	0072-1077
CD	GSAPAZ
PB	"Geological Society of America (GSA), Boulder, CO, United States (USA)"
DE	(U-Th)/He; absolute age; batholiths; California; cooling; Cretaceous;crust; dates; exhumation; geologic barometry; geologic thermometry;intrusions; Kern County California; magmatism; Mesozoic; metamorphicrocks; metamorphism; nesosilicates; orthosilicates; Paleozoic;protoliths; Rand Schist; rates; retrograde metamorphism; schists;Sierra Nevada; Sierra Nevada Batholith; silicates; tectonics;Tehachapi Mountains; thermal history; thermochronology; U/Pb; UnitedStates; zircon; zircon group
AB	"The Tehachapi complex lies at the southern end of the Sierra Nevadabatholith adjacent to the Neogene-Quaternary Garlock fault. Thecomplex is composed principally of high-pressure (8-10 kbar)Cretaceous batholithic rocks, and it represents the deepest exposedlevels of a continuous oblique crustal section through the southernSierra Nevada batholith. Over the southern approximately 100 km ofthis section, structural/petrologic continuity and geochronologicaldata indicate that > or =35 km of felsic tointermediate-composition crust was generated by copious arc magmatismprimarily between 105 and 99 Ma. In the Tehachapi complex, thesebatholithic rocks intrude and are bounded to the west bysimilar-composition gneissic-textured high-pressure batholithic rocksemplaced at ca. 115-110 Ma. This lower crustal complex is boundedbelow by a regional thrust system, which in Late Cretaceous timetectonically eroded the underlying mantle lithosphere, and in seriesdisplaced and underplated the Rand Schist subduction assemblage bylow-angle slip from the outboard Franciscan trench. Geophysical andmantle xenolith studies indicate that the remnants of this shallowsubduction thrust descend northward through the crust and into themantle, leaving the mantle lithosphere intact beneath the greaterSierra Nevada batholith. This north-dipping regional structure recordsan inflection in the Farallon plate, which was segmented into ashallow subduction trajectory to the south and a normal steepertrajectory to the north. We combine new and published data from abroad spectrum of thermochronometers that together form a coherentdata array constraining the thermal evolution of the complex.Integration of these data with published thermobarometric andpetrogenetic data also constrains the tectonically drivendecompression and exhumation history of the complex. The timing of arcmagmatic construction of the complex, as denoted above, is resolved bya large body of U/Pb zircon ages. High-confidence thermochronometricdata track a single retrogressing path commencing from widelyestablished solidus conditions at ca. 100 Ma, and traversing throughtime-temperature space as follows: (1) Sm/Nd garnet approximately770-680 degrees C at ca. 102-95 Ma, (2) U/Pb titanite approximately750-600 degrees C at ca. 102-95 Ma, (3) Ar/Ar hornblende approximately570-490 degrees C at ca. 94-91 Ma, (4) Rb/Sr biotite approximately390-260 degrees C at ca. 90-86 Ma, (5) Ar/Ar biotite approximately320-240 degrees C at ca. 88-85 Ma, and (6) (U-Th)/He zirconapproximately 230-170 degrees C at ca. 88-83 Ma. Additionalstratigraphic constraints place the complex at surface conditions inPaleocene-early Eocene time (ca. 66-55 Ma). Integration of theseresults with thermobarometric and structural data, including publisheddata on the underlying Rand Schist, reveals a profound tectonic eventwhereby rapid cooling and exhumation at rates potentially as high as100s degrees C/m.y. and >5 mm/yr initiated at ca. 98 Ma and peakedbetween 96 and 94 Ma. Between 93 and 85 Ma, cooling rates remainedhigh, but decelerated with or without significant exhumation.Subsequent cooling and exhumation rates are poorly constrained butwere much slower and ultimately resulted in Paleocene-Eocene surfaceexposure. Initial rapid exhumation and cooling are hypothesized tohave been driven by abrupt flattening in the corresponding segment ofthe Farallon plate and the resulting tectonic erosion of theunderlying mantle lithosphere. Protolith as well as metamorphicpressure-temperature and age constraints on the Rand Schist indicateits rapid low-angle subduction between 93 and 88 Ma. Comparison of theRand Schist and Tehachapi complex pressure-temperature-time paths inconjunction with structural relations strongly suggest that the schistascended the equivalent of approximately 4 kbar relative to theTehachapi complex by low-angle normal displacement along the Randfault between 88 and 80 Ma to attain its current underplatedstructural position. Such extensional tectonism is hypothesiz ed tohave been driven by slab rollback during the demise of the southernCalifornia region shallow slab segment."
LA	English
FE	"References: 100; illus. incl. 6 tables, geol. sketch map"
PY	2007
PT	Serial; Conference document; Analytic
CP	United States (USA)
LL	"Latitude:N344500,N351500 Longitude:W1181500,W1185000"
CL	16 Structural geology; 03 Geochronology
CY	"GeoRef, Copyright 2007, American Geological Institute."
UD	200717
DO	10.1130/2007.2419
AN	2007-075911
JV	419
JP	39-66
Sample Data																																														
Item	Age	Max_age	Min_age	Age	Max_age	Min_age	Age	Max_age	Min_age	Age	Max_age	Min_age	Age	Max_age	Min_age	Age	Max_age	Min_age	Age	Max_age	Min_age	Age	LatDD	LongDD	Loc_prec	Sm	Nd	143_144Nd	143_144Nd	Rb	Sr	87_86Sr	87_86Sr	87_86Sr	U	Th	U	Pb	Location_Name	Rock_Class	Rock_Type	Sample_Description	Sample_Comment	Collected_by	Material	State
Units	Ma	Ma 	Ma	Ma	Ma 	Ma	Ma	Ma 	Ma	Ma	Ma 	Ma 	Ma	Ma 	Ma	Ma	Ma 	Ma	Ma	Ma 	Ma	Ma	DD	DD	DD	ppm	ppm			ppm	ppm				ppm	ppm	ppm	ppm								
Method	1	1	1	2	2	2	3	3	3	4	4	4	5	5	5	6	6	6	7	7	7	8	9	9		10	10	11	12	13	13	14	15	16	10	10	17	17								
Sample Name																																														
4	99.2	100.1	98.3	113.5	115	112																	34.9273	-118.9144	0.001												113	1.78	Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss		Saleeby and others	mineral	California
4	98.9	99.9	97.9	113.5	115	112																	34.9273	-118.9144	0.001												151	2.02	Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss		Saleeby and others	mineral	California
7	102.1	103.2	101	112	113.5	110.5																	34.9279	-118.8278	0.001												101	1.4	Tehachapi Mts	granodiorite	metamorphic	hornblende biotite granodiorite gneiss		Saleeby and others	mineral	California
12	96.5	97.8	95.2	110.5	111.5	109.5																	35.0106	-118.7602	0.001												143	1.87	Tehachapi Mts	tonalite	metamorphic	hornblende biotite tonalite gneiss		Saleeby and others	mineral	California
12	95.9	96.8	95	110.5	111.5	109.5																	35.0106	-118.7602	0.001												178	2.31	Tehachapi Mts	tonalite	metamorphic	hornblende biotite tonalite gneiss		Saleeby and others	mineral	California
13	97	98	96	116.5	118	115																	35.024	-118.6987	0.001												222	2.91	Tehachapi Mts	tonalite	metamorphic	hypersthene biotite tonalite gneiss		Saleeby and others	mineral	California
16	95.1	96	94.2	111.5	113	110																	35.0184	-118.6556	0.001												298	3.83	Tehachapi Mts	granodiorite	metamorphic	biotite granodiorite gneiss		Saleeby and others	mineral	California
1							96.8	99.7	93.9														34.9043	-118.9178	0.001	2.54	1.21		0.513361										Bear Valley 	gabbro	plutonic	migmatitic hornblende gabbro	"The Sm/Nd ages were performed on garnet, not on whole rock.  Navdat would not accept the garnet designation in the method section.  The 143_144Nd data was obtained by MC-ICP-MS on garnet."	Saleeby and others	mineral	California
2							99	102.1	95.9														34.9256	-118.9279	0.001	2.09	1.55		0.51324										Bear Valley	tonalite	plutonic	garnet biotite tonalite	"The Sm/Nd ages were performed on garnet, not on whole rock.  Navdat would not accept the garnet designation in the method section.  The 143_144Nd data was obtained by MC-ICP-MS on garnet."	Saleeby and others	mineral	California
5							95.9	98.9	92.9														34.9266	-118.8651	0.001	3.11	1.8		0.513431										Bear Valley	diorite	plutonic	migmatitic hornblende diorite	"The Sm/Nd ages were performed on garnet, not on whole rock.  Navdat would not accept the garnet designation in the method section.  The 143_144Nd data was obtained by MC-ICP-MS on garnet."	Saleeby and others	mineral	California
6b							102.2	105.1	99.3														34.9204	-118.8269	0.001	2.93	1.94		0.51327										Tehachapi Mts	gabbro	plutonic	amphibolitic gabbro layer	"The Sm/Nd ages were performed on garnet, not on whole rock.  Navdat would not accept the garnet designation in the method section.  The 143_144Nd data was obtained by MC-ICP-MS on garnet."	Saleeby and others	mineral	California
15							94.8	97.5	92.1														34.9857	-118.7291	0.001	2.21	1.02		0.513374										Bear Valley	gabbro	plutonic	migmatitic hornblende gabbro	"The Sm/Nd ages were performed on garnet, not on whole rock.  Navdat would not accept the garnet designation in the method section.  The 143_144Nd data was obtained by MC-ICP-MS on garnet."	Saleeby and others	mineral	California
3										87.64	88.74	86.54				86.75	86.99	86.51					34.9226	-118.9292	0.001					314.69	8.69	0.8395							Tehachapi Mts	migmatite	metamorphic	migmatitc paragneiss		Saleeby and others	mineral	California
4										87.5	88.6	86.4											34.9273	-118.9144	0.001					199	31.07	0.72913							Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss		Saleeby and others	mineral	California
6										89.1	90.3	87.9											34.9204	-118.8269	0.001					295.1	39.14	0.73228							Tehachapi Mts	tonalite	metamorphic	garnet hornblende tonalite gneiss		Saleeby and others	mineral	California
6																			91.35	92.02	90.68		34.9204	-118.8269	0.001														Tehachapi Mts	tonalite	metamorphic	garnet hornblende tonalite gneiss		Saleeby and others	mineral	California
6b																			93.67	94.45	92.89		34.9204	-118.8269	0.001					3.34	61.19		0.70434						Tehachapi Mts	gabbro	plutonic	amphibolitic gabbro layer		Saleeby and others	mineral	California
7																			94.68	95.32	94.04		34.9279	-118.8278	0.001					2.94	41.47		0.70481						Tehachapi Mts	granodiorite	metamorphic	hornblende biotite granodiorite gneiss		Saleeby and others	mineral	California
7										87	88.1	85.9				85.13	85.61	84.65					34.9279	-118.8278	0.001					321.4	28.69	0.74513							Tehachapi Mts	granodiorite	metamorphic	hornblende biotite granodiorite gneiss		Saleeby and others	mineral	California
9										89.2	90.3	88.1											34.9285	-118.7994	0.001					93.4	25.74	0.71834							Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss		Saleeby and others	mineral	California
11										86.9	88.2	85.6				88.5	89.6	87.4					35.0036	-118.7663	0.001					376.97	18.62	0.77783							Bear Valley	tonalite	plutonic	hornblende biotite tonalite		Saleeby and others	mineral	California
12										84.1	85.4	82.8				88.02	88.29	87.75					35.0106	-118.7602	0.001					390.69	26.32	0.75718							Tehachapi Mts	tonalite	metamorphic	hornblende biotite tonalite gneiss		Saleeby and others	mineral	California
12																			93.81	94.67	92.95		35.0106	-118.7602	0.001														Tehachapi Mts	tonalite	metamorphic	hornblende biotite tonalite gneiss		Saleeby and others	mineral	California
13										86.6	87.7	85.5											35.024	-118.6987	0.001					121	29.22	0.72001							Tehachapi Mts	tonalite	metamorphic	hypersthene biotite tonalite gneiss		Saleeby and others	mineral	California
16										84	85.3	82.7				80.5	80.77	80.23					35.0184	-118.6556	0.001					698.1	12.22	0.90637							Tehachapi Mts	granodiorite	metamorphic	biotite granodiorite gneiss		Saleeby and others	mineral	California
17a										86.5	87.7	85.3				85.13	85.61	84.65					34.9569	-118.6785	0.001					425.2	27.12	0.76012							Tehachapi Mts	tonalite	metamorphic	hornblende biotite tonalite gneiss		Saleeby and others	mineral	California
17b																			93.02	93.59	92.45		34.9569	-118.6785	0.001					6.09	57.01		0.70471						Tehachapi Mts	diorite	metamorphic	hornblende diorite gneiss layer		Saleeby and others	mineral	California
18										84.2	85.3	83.1											34.9598	-118.6728	0.001					96.1	15.99	0.72581							Tehachapi Mts	tonalite	metamorphic	two-pyroxene biotite hornblende tonalite gneiss		Saleeby and others	mineral	California
19										82.4	83.4	81.4											34.9856	-118.5898	0.001					349	21.32	0.76024							Bear Valley	tonalite	plutonic	hypersthene biotite tonalite		Saleeby and others	mineral	California
20										84.9	86.4	83.4											35.0414	-118.5849	0.001					215	21.02	0.74267							Tehachapi Mts	tonalite	plutonic	biotite tonalite		Saleeby and others	mineral	California
21													88.1	89.6	86.6				85.21	85.65	84.77		35.1342	-118.5484	0.001					15.34	14.74		0.70908						Tehachapi Mts	tonalite	plutonic	hornblende biotite tonalite		Saleeby and others	mineral	California
21										75.2	76.3	74.1				81.64	81.95	81.33					35.1342	-118.5484	0.001					513.47	17.22	0.79872							Tehachapi Mts	tonalite	plutonic	hornblende biotite tonalite		Saleeby and others	mineral	California
4																						89.11578	34.9273	-118.9144	0.001										227.2123	32.17508			Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
4																						86.58508	34.9273	-118.9144	0.001										315.2301	59.66178			Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
4																						82.49177	34.9273	-118.9144	0.001										213.7395	48.45461			Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
4																						86.25581	34.9273	-118.9144	0.001										330.6318	76.84918			Tehachapi Mts	tonalite	metamorphic	garnet biotite tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						64.77759	34.9391	-118.8239	0.001										1053.867	1163.323			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						87.79203	34.9391	-118.8239	0.001										981.6888	276.4141			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						81.12016	34.9391	-118.8239	0.001										1410.743	179.2173			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						87.05732	34.9391	-118.8239	0.001										989.89	214.5463			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						93.39998	34.9391	-118.8239	0.001										1554.803	88.88688			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						86.17686	34.9391	-118.8239	0.001										305.1595	64.49503			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
8																						90.28484	34.9391	-118.8239	0.001										1629.731	145.2439			Tehachapi Mts	granite	metamorphic	biotite granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						77.04646	34.9285	-118.7994	0.001										670.218	80.83152			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						79.08343	34.9285	-118.7994	0.001										494.1944	121.1419			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						91.05411	34.9285	-118.7994	0.001										509.0096	133.5293			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						93.4392	34.9285	-118.7994	0.001										509.4136	163.672			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						95.66454	34.9285	-118.7994	0.001										710.1119	153.2446			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						97.18071	34.9285	-118.7994	0.001										494.7477	86.09419			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
9																						105.1566	34.9285	-118.7994	0.001										450.0234	124.2753			Tehachapi Mts	tonalite	metamorphic	epidote garnet tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
10																						94.03737	34.919	-118.7967	0.001										725.2795	141.8892			Tehachapi Mts	granite	metamorphic	granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
10																						102.7316	34.919	-118.7967	0.001										537.9345	143.6547			Tehachapi Mts	granite	metamorphic	granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
10																						87.12724	34.919	-118.7967	0.001										526.013	146.6714			Tehachapi Mts	granite	metamorphic	granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
10																						83.88723	34.919	-118.7967	0.001										358.4952	28.60761			Tehachapi Mts	granite	metamorphic	granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
10																						80.15028	34.919	-118.7967	0.001										317.3455	55.63947			Tehachapi Mts	granite	metamorphic	granite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
14																						92.79486	34.9804	-118.7533	0.001										703.9958	67.37327			Tehachapi Mts	gabbro	plutonic	two-pyroxene hornblende gabbro	U-Th age performed on zircon.	Saleeby and others	mineral	California
14																						83.95101	34.9804	-118.7533	0.001										413.4325	59.77054			Tehachapi Mts	gabbro	plutonic	two-pyroxene hornblende gabbro	U-Th age performed on zircon.	Saleeby and others	mineral	California
14																						82.66252	34.9804	-118.7533	0.001										763.1294	172.2376			Tehachapi Mts	gabbro	plutonic	two-pyroxene hornblende gabbro	U-Th age performed on zircon.	Saleeby and others	mineral	California
14																						86.62948	34.9804	-118.7533	0.001										435.7494	71.71893			Tehachapi Mts	gabbro	plutonic	two-pyroxene hornblende gabbro	U-Th age performed on zircon.	Saleeby and others	mineral	California
14																						80.53261	34.9804	-118.7533	0.001										336.0777	48.74379			Tehachapi Mts	gabbro	plutonic	two-pyroxene hornblende gabbro	U-Th age performed on zircon.	Saleeby and others	mineral	California
18																						78.58032	34.9598	-118.6728	0.001										150.0283	40.96633			Tehachapi Mts	tonalite	metamorphic	two-pyroxene biotite hornblende tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
18																						73.69325	34.9598	-118.6728	0.001										40.4532	13.03194			Tehachapi Mts	tonalite	metamorphic	two-pyroxene biotite hornblende tonalite gneiss	U-Th age performed on zircon.	Saleeby and others	mineral	California
19																						74.7153	34.9856	-118.5898	0.001										289.5867	22.11804			Bear Valley	tonalite	plutonic	hypersthene biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
19																						75.17251	34.9856	-118.5898	0.001										100.0072	22.32668			Bear Valley	tonalite	plutonic	hypersthene biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
19																						70.30939	34.9856	-118.5898	0.001										145.5559	22.91059			Bear Valley	tonalite	plutonic	hypersthene biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
20																						75.38772	35.0414	-118.5849	0.001										244.275	76.58532			Tehachapi Mts	tonalite	plutonic	biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
20																						81.06873	35.0414	-118.5849	0.001										434.1333	125.6954			Tehachapi Mts	tonalite	plutonic	biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
20																						75.20905	35.0414	-118.5849	0.001										298.6783	104.0468			Tehachapi Mts	tonalite	plutonic	biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
20																						85.47001	35.0414	-118.5849	0.001										309.043	70.94722			Tehachapi Mts	tonalite	plutonic	biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
20																						93.46009	35.0414	-118.5849	0.001										221.3544	70.18708			Tehachapi Mts	tonalite	plutonic	biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
20																						95.37998	35.0414	-118.5849	0.001										216.996	68.14307			Tehachapi Mts	tonalite	plutonic	biotite tonalite	U-Th age performed on zircon.	Saleeby and others	mineral	California
Method Data																																														
1	U-PB6:SPHENE	77																																												
2	U-PB6:ZIRC	77																																												
3	SM-ND:WR	77																																												
4	RB-SR:BIO	56
5	RB-SR:HB	56
6	AR-AR:BIO	56
7	AR-AR:HB	56
8	U-TH	77
9	MAP	2007-075911
10	ICPMS	77
11	MC_ICP_MS	77
12	MS	77
13	XRF-EDS	56
14	MS	56
15	MS	56
16	MS	56
17	MC_ICP_MS	77