The Dishman Hills: Or How We The Dishman Hills: Or How We Learned to Stop Worrying and Love Learned to Stop Worrying and Love the Rocksthe Rocks

Taylor DeWittTaylor DeWitt

Ryan PointerRyan Pointer

Janae KaschmitterJanae Kaschmitter

Kaelynne ByersKaelynne Byers

Introduction & PurposeIntroduction & Purpose

In this presentation we will discuss the rocks and In this presentation we will discuss the rocks and geological features of the Dishman-Mica geological features of the Dishman-Mica conservation area, as well as its history and conservation area, as well as its history and recreation activities available.recreation activities available.

Our purpose was to research and identify the Our purpose was to research and identify the geological makeup of the Dishman Hills.geological makeup of the Dishman Hills.

Project LocationProject Location Location: Spokane Valley along Appleway Blvd and Sargent Location: Spokane Valley along Appleway Blvd and Sargent

Rd.Rd. Directions: Take I90 E, take the Sprague exit (exit 285), Directions: Take I90 E, take the Sprague exit (exit 285),

onto Appleway Blvd. Keep going east on Appleway until onto Appleway Blvd. Keep going east on Appleway until Sargent Rd. Turn right on Sargent Rd. the Dishman Hills Sargent Rd. Turn right on Sargent Rd. the Dishman Hills parking lot is the first turn on your right.parking lot is the first turn on your right.

Fig. 1 Map displaying route to Dishman Hills when going east in I-90. Satellite image courtesy of Google Maps.Fig. 1 Map displaying route to Dishman Hills when going east in I-90. Satellite image courtesy of Google Maps.

General boundary General boundary of the Dishman of the Dishman Hills Natural AreaHills Natural Area.

Fig. 2 Google Map zoomout Fig. 2 Google Map zoomout showing size and scale of showing size and scale of Dishman Hills Natural AreaDishman Hills Natural Area

Site 1Site 1Site 2Site 2Site 3Site 3

Fig. 3 Satellite zoom-in showing placement of site locationsFig. 3 Satellite zoom-in showing placement of site locations

Parking Parking SpotSpot

Site GeologySite Geology Based on geological maps by R. E. Derkey et al. Based on geological maps by R. E. Derkey et al. Area consists of pre-Tertiary quartz-feldspar-mica Area consists of pre-Tertiary quartz-feldspar-mica

orthogneiss (pTog).orthogneiss (pTog). Intrusions of Tertiary-Cretaceous fine grained, biotite-Intrusions of Tertiary-Cretaceous fine grained, biotite-

muscovite granite (Tki).muscovite granite (Tki). According to S. Babcock and B. Carson, the Dishman According to S. Babcock and B. Carson, the Dishman

Hills were formed when magma crept its way up to the Hills were formed when magma crept its way up to the Belt-Purcell Supergroup and cooled into a granite.Belt-Purcell Supergroup and cooled into a granite.

Granite was buried by Columbia River Basalts; and all Granite was buried by Columbia River Basalts; and all was eroded by the Missoula Floods.was eroded by the Missoula Floods.

Site Location: Spokane NE 7.5’ QuadrangleSite Location: Spokane NE 7.5’ QuadrangleR 44 E, T 25 N, S 19R 44 E, T 25 N, S 19

Site 1

Site 3Site 2

Fig. 4 Site locations on Spokane NE 7.5’ Quadrangle geological Map (Derkey, et al.,1999)Fig. 4 Site locations on Spokane NE 7.5’ Quadrangle geological Map (Derkey, et al.,1999)

Parking Spot

At this site we found a subcrop of weakly metamorphosed felsic At this site we found a subcrop of weakly metamorphosed felsic orthogneiss. Veins of lighter colored quartz & feldspar are seen in the orthogneiss. Veins of lighter colored quartz & feldspar are seen in the rock averaging about half-inch to an inch in thickness with properties rock averaging about half-inch to an inch in thickness with properties consistent with pegmatite.consistent with pegmatite.

Fig.5 Pegmatite veins in subcrop embedded in Fig.5 Pegmatite veins in subcrop embedded in the ground. The lighter bands are majority the ground. The lighter bands are majority quartz & feldspar.quartz & feldspar.

Site 1Site 1

This site also consists heavily of orthogneiss and This site also consists heavily of orthogneiss and pegmatite. It has a well defined foliation as compared to pegmatite. It has a well defined foliation as compared to what was seen at site 1 (Fig. 6). The bands of quartz-what was seen at site 1 (Fig. 6). The bands of quartz-feldspar-pegmatite are also thicker ranging 1-5 inches feldspar-pegmatite are also thicker ranging 1-5 inches thick (Fig. 7).thick (Fig. 7).

Fig. 6 Outcrop displaying the high grade foliation of Fig. 6 Outcrop displaying the high grade foliation of pegmatite and feldspar.pegmatite and feldspar.

Fig. 7 Bands of quartz feldspar inside the pegmatite with Fig. 7 Bands of quartz feldspar inside the pegmatite with mechanical pencil for scale.mechanical pencil for scale.

Site 2Site 2

Site 3Site 3This location of orthogneiss was cream colored due to sediment erosion from This location of orthogneiss was cream colored due to sediment erosion from the top of the outcrop (Fig. 8). Facing east from the outcrop, a subcrop of the top of the outcrop (Fig. 8). Facing east from the outcrop, a subcrop of orthogneiss and pegmatite can be seen where the pegmatite bands range orthogneiss and pegmatite can be seen where the pegmatite bands range from several inches up to several feet wide (Fig. 9).from several inches up to several feet wide (Fig. 9).

Fig. 8: Hillside of orthogneiss.Fig. 8: Hillside of orthogneiss. Fig. 9: Subcrop of pegmatite & orthogneiss (standard Fig. 9: Subcrop of pegmatite & orthogneiss (standard notebook for scale).notebook for scale).

Area HistoryArea History The Dishman Hills is a 530 acre area that was set aside The Dishman Hills is a 530 acre area that was set aside

as a conservancy in 1966 due to the development around as a conservancy in 1966 due to the development around the area. Residents wanted a place set aside that would the area. Residents wanted a place set aside that would not be disrupted for the wildlife. It is protected by both not be disrupted for the wildlife. It is protected by both profit and non profit organizations.profit and non profit organizations.

In July 2008, a wildfire broke out over the Dishman Hills In July 2008, a wildfire broke out over the Dishman Hills and destroyed 1200 acres of land and 13 homes. The and destroyed 1200 acres of land and 13 homes. The area has since recovered.area has since recovered.

Recreation, Wildlife, Recreation, Wildlife, Plants, etc.Plants, etc. The Dishman Hills boasts numerous trails for people to The Dishman Hills boasts numerous trails for people to

wander and adventure along. wander and adventure along.

Fig. 10: Map of Dishman Hills Trails.Fig. 10: Map of Dishman Hills Trails.

Recreation, Wildlife, Recreation, Wildlife, Plants, etc. (cont.)Plants, etc. (cont.)

Dishman Hills has a wide variety of plant and animal Dishman Hills has a wide variety of plant and animal lifelife

Animal species include coyotes, weasels, squirrels, Animal species include coyotes, weasels, squirrels, chipmunks, marmots, porcupines, cottontail rabbits, chipmunks, marmots, porcupines, cottontail rabbits, and white-tailed deer. Raptors, ruffed tailed grouse, and white-tailed deer. Raptors, ruffed tailed grouse, pheasants, and more than 50 species of butterfliespheasants, and more than 50 species of butterflies

Flora includes grass widows and arrowleaf balsamroot Flora includes grass widows and arrowleaf balsamroot serviceberry, wild rose, ocean spray, glacier lilies (Fig. serviceberry, wild rose, ocean spray, glacier lilies (Fig. 11) and bearded iris (Fig. 12).11) and bearded iris (Fig. 12).

Fig. 11: Field of Glacier LiliesFig. 11: Field of Glacier Lilies(Image Courtesy of Dishman Hills Conservancy)(Image Courtesy of Dishman Hills Conservancy)

Fig 12: A sample of Bearded Iris.Fig 12: A sample of Bearded Iris.

ConclusionConclusion In conclusion we learned that the Spokane area is In conclusion we learned that the Spokane area is

rich in geological history and natural beauty. And rich in geological history and natural beauty. And fortunately for us, the Dishman Hills allows us to fortunately for us, the Dishman Hills allows us to explore that history and beauty without leaving the explore that history and beauty without leaving the city.city.

ReferencesReferences Babcock, S., Carson, B. Hiking Washington’s Geology. Seattle: The Babcock, S., Carson, B. Hiking Washington’s Geology. Seattle: The

Mountaineers, 2000Mountaineers, 2000 Derkey, R.E., Hamilton, M.M., and Stradling, D.F., 1999 Priliminary Geologic Derkey, R.E., Hamilton, M.M., and Stradling, D.F., 1999 Priliminary Geologic

Map of the Spokane NE 7.5-Minute Quadrangle, Spokane County, Washington: Map of the Spokane NE 7.5-Minute Quadrangle, Spokane County, Washington: Washington Division of Geology and Earth Resources, Open File Report 1999-6Washington Division of Geology and Earth Resources, Open File Report 1999-6

Dishman Hills Conservancy. http://www.dishmanhills.org/Dishman Hills Conservancy. http://www.dishmanhills.org/ Dishman Hills NRCA. Dishman Hills NRCA.

http://www.dnr.wa.gov/AboutDNR/ManagedLands/Pages/amp_na_dishman.asphttp://www.dnr.wa.gov/AboutDNR/ManagedLands/Pages/amp_na_dishman.aspxx

Dishman Hills Loop. Trails.com. http://www.trails.com/tcatalog_trail.aspx?Dishman Hills Loop. Trails.com. http://www.trails.com/tcatalog_trail.aspx?trailid=HGW036-019trailid=HGW036-019

Google MapsGoogle Maps Geranios, N. K. 2008 Wildfire Destroys 13 Homes in Spokane Area; 200 Geranios, N. K. 2008 Wildfire Destroys 13 Homes in Spokane Area; 200

Evacuated. http://www.komonews.com/news/local/24385459.htmlEvacuated. http://www.komonews.com/news/local/24385459.html