Site Location and geology of the Washington Creek site.

The site is located 400 m north of Washington creek. It lies within a region of highland and low mountains. Near by summits reach 2500 feet in elevation; according to data obtained by the Alaska Department and Transportation (DOT) bedrock found at the site corresponds to the Fairbanks Schist unit of Paleozoic age that includes mica schist, quartz-mica schist and schistose quartzite (Wilson and others, 1998). Samples collected at the site by the UAF geophysics team indicate an organic layer from 0.0 to 0.1 m depth; from 0.1 to 0.25 a brown fine-grained silty- clay with medium-grained micas; there is another layer from 0.25 to 08 m depth of frozen fine-grained brown ice reach silty clay with visible ice lenses. Vegetation around the site consists of moss, labrador tea and spruce trees, which are indicators of permafrost in the area. The Washington creek site lies between two large strike-slip faults systems. The Denali fault which is 110 miles to the south and the Tintina fault about 35 to 40 m north. There are several northeast trending faults in the area of study. The area is a region of continuous permafrost; the active layer or seasonal frost penetration depth may exceed 3.5 m. In undisturbed areas with snow accumulation, seasonal frost penetration may be less than 3 feet (Rowland, 2006). For a better description of the soil, the next tables summarize properties of the soil collected at the site.

Mass properties of the Washington creek site samples.

Sample	MASS (g)
	can	can +wet soil	can +dry soil	water	dry soil	moisture content
1	44.71	295.48	151.00	144.48	106.29	135.93
2	44.68	129.64	79.14	50.50	34.46	146.55
3	44.67	262.83	170.80	92.03	126.13	72.96
4	44.68	101.11	70.20	30.91	25.52	121.12

Volumetric properties of the Washington Creek site Samples.

Volume Calculation
Vw	Vt	Vs	Vv	Satur	n	ϴ Volumetric water cont	ɣ d of soil	Dry w of soil	Weight of water
144.48	191.50	40.11	151.40	95.43	79.06	75.44	0.56	0.56	1.31
50.50	74.61	13.00	61.61	81.97	82.57	67.68	0.46	0.46	1.14
92.03	137.54	47.60	89.95	102.31	65.40	66.91	0.92	0.92	1.59
30.91	48.86	9.63	39.23	78.78	80.29	63.26	0.52	0.52	1.15

The samples were collected during our resistivity survey on the past October 27, 2009, along our survey line.

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