Sibley Volcanic Regional Preserve N ORINDA O D Y
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Sibley Volcanic Regional Preserve N ORINDA O D Y . A N D O R A R 24 TO C Massive basalt was removed from this major HOW MANY VOLCANOES? Besides Round MORAGA ROAD FISH T Sibley Volcanic RANCH HURS 5 quarry pit. The north wall shows a set of thick lava Top, there are smaller ones outside the Preserve Huckleberry PINE WILDCAT CYN. ROAD Sibley Botanic Reg. Volcanic Redwood Regional Park . Preserve flows tilted on edge, nearly vertical. The well-defined to the north and southeast. Another, of rhyodacitic Tilden RegionalRK DR ParkBL. Preserve S. PA SK . Roberts Regional Preserve BOTANIC Y layers near the top of the face are jointing-units composition, underlies the Lawrence Berkeley Labo- LINE D Regional D BL. PEAK R SKYLINE GARDEN R Rec. Area E Claremont N BL. H O GRIZZLY P ratory and Little Grizzly Peak in Tilden Regional Park. Canyon Reg. Y N I . resulting from shrinkage caused by cooling. They are E N H U R D S Preserve A Q E ROAD BART R C L A L Oakland, Berkeley, Orinda O I D analogous to the basalt pillars of Devil’s Postpile in About 9.8 million years ago it was erupting beside BERKELEY J M O 13 WO CLAREMONT AV. D Temescal L E I R OXFORD AV. the southern Sierra. Round Top. Subsequently it was shifted about three N Reg.Rec. PARK SHA TELEGRAPH AV. C AV. Area Y O TTUCK AV. A L This is a sequence of basaltic tuffs (ash) lying on and one-half miles northwest by movement along N W D TERR. A OAKLAND BL. 6 35TH top of a dark lava (far left), all tilted steeply to the Wildcat Fault. That makes a total of four volcanoes. O MORAGA AV. R GR B A HIGH N BROAD WAY D FRUITVALE AV. east. The base of the tuffs was baked red, probably THIS PRESERVE is named to honor Robert Sibley, A V . ST. because the lava below was still hot and steaming AV. a founder and director of the East Bay Regional Park SAN ASHBY PA BLO AV. AV. when the ash landed. At the top of the sequence UNIVERSITY District, and president of the Board of Directors from 580 13 Lake ST. 880 there is another lava flow (far right, to the right of 1948 until his death in 1958. The original 227-acre Merritt E. 14TH McLaughlin HIGH ST. the post) that baked the underlying tuffs red. Eastshore Preserve was dedicated with Tilden Regional Park and AV. State Park 980 PARK ST. Before you is a basalt flow, massive at left, rubbly Temescal Regional Recreation Area in October 1936, 7 GRAND to the right. The lower parts, coming into contact 61 WEBSTER ALAMEDA two years after the Park District’s formation. Vari- North 880 with cold land surfaces, harden early and are often ous parcels have been added to the preserve over the 80 ENCINAL AV. 0 1 2 Miles McKAY CENTRALAV. Crown Beach jumbled by turbulence and drag. The rubbly part of years, including a 250-acre parcel in 2010. AV. & Crab Cove the flow is filled with vesicles caused by gas pockets, At the southern park boundary is 240-acre Huckle- which were later filled with chalcedony, opal, calcite, berry Botanic Regional Preserve. The Skyline National To Reach Sibley Volcanic Regional Preserve: zeolites, and sometimes green celadonite. Recreation Trail, which connects Richmond-El So- From Highway 24 just east of the Caldecott Tunnel, This huge, reddish-brown block of lava fell from the brante to Castro Valley, traverses both of these parks. take the Fish Ranch Road exit and go north, uphill, for 8 cliffs to the upper right. The lava cooled and hard- 0.8 miles to Grizzly Peak Blvd. Turn left and go 2.4 WELCOME! Please enjoy the Regional Parks safely, and ened while it was still moving, resulting in dramatic frag- miles to Skyline Boulevard. Turn left on Skyline and help us protect and preserve your parklands by complying with proceed to the park entrance, on the left. PUBLIC mentation, known as “autobrecciation” (self-broken). park rules and regulations. Photo by Michael Short See hard lava to the right and left, and soft, easily SAFETY and ETIQUETTE TRANSIT: The closest bus line is AC Transit #18, 9 eroded tuff between, all tilted eastward almost to • Stay on trails. Taking shortcuts can be dangerous and which runs to the Montclair Transit Center in Mont- vertical. The lava to the left baked the top of the tuffs causes erosion. clair. From 12th Street BART or 19th Street BART, brick red. This lava looks as if it was probably 100-150 • Wading and/or swimming in undesignated areas may be take AC Transit bus #18 to the Montclair Transit dangerous and may harm the watershed. Center. Call AC Transit to confirm transit information: feet thick. These flows were not fluid, but contained • Carry and drink plenty of water. Dehydration is a leading dial 511 (TDD/TTY: 1-800-448-9790). enough silica to be more viscous. They probably cause of injuries on the trail. moved at a slow walk, with glowing blocks of lava tum- • Be prepared for sudden changes in weather conditions. bling down a steep front and setting vegetation on fire. • Trails can be slippery, rocky and steep. Proceed carefully at your own risk. 10 The brick-red knobs in the foreground, and rug- • Wildlife may be present on the trails at any time. ged outcrops of the same color on the skyline, Feeding or approaching wildlife is dangerous and illegal. are made of cinder that flew from Round Top and • Bicycles are permitted on designated trails only. Horses have the right-of-way on trails. landed while still hot, so the pieces welded together. Photo by Jerry Ting The major valley to the north across Highway • Keep the parks beautiful. Pack out what you pack in. 11 RULES 24 is Siesta Valley. It coincides with the axis of • Dogs must be leashed 200 feet from any trail or park the Siesta Syncline, a great fold that has lifted up entrance. Dogs must be leashed in parking lots, picnic areas, thousands of feet of rocks on both sides. You are developed areas such as lawns and play fields, and on some standing on the southwest limb of the fold, which trails. They must be under voice control at all times. includes all the rocks in Sibley. • State law requires that all bicyclists under age 18 wear an approved helmet while riding on trails and roadways. East Bay Regional Park District Equestrians and bicyclists are also strongly encouraged to wear 2950 Peralta Oaks Court, helmets at all times. POLICE, FIRE, MEDICAL EMERGENCY ...............9-1-1 P.O. Box 5381 • Smoking is prohibited, except in overnight campsites. Oakland, CA 94605-0381 EBRPD HEADQUARTERS .................... 1-888-327-2757 • Drones are prohibited. PARK OFFICE ........ 1-888-327-2757, option 3, ext. 4554 1-888-327-2757 (1-888-EBPARKS) TRS RELAY FOR THE HEARING IMPAIRED ........7-1-1 Visitors are responsible for knowing and complying with park www. ebparks.org Rev. 7/17 rules, available online at www.ebparks.org/rules. California poppies. Photo by Isa Polt-Jones A B C D E F G H I J K L 24 EBMUD WATERSHED. DOGS AND HORSES ARE NOT Hiking permit required To Walnut Creek 1400 PERMITTED IN HUCKLEBERRY AREA IN YELLOW except when hiking on except passing through on the Skyline National Trail. SUBJECT TO CLOSURE 1 Skyline Trail/Bay Area 11 DOGS MUST BE UNDER VOICE See www.ebparks.org/ Ridge Trail. Call 10 sibley for status. NO ACCESS Quarry Pit 5 CONTROL AT ALL TIMES. BEYOND GATES (510) 287-0459. .11 HORSES MUST STAY 9 .11 4 ON THE SKYLINE TRAIL. 8 7 6 .04 .07 Quarry Pit .06 IC T .14 .28 3 1000 1300 .19 N RA TRAIL 2 .04 CA I VOLC .03 BICYCLES ARE NOT PERMITTED L L ANIC .131500 .11 Trail O IN HUCKLEBERRY FENCELINE V 1400 p .08 .04 .12 AIL L REGIONAL BOTANIC PRESERVE. TR I 1200 .13 .29 A o SIBLEY .03 1100 .15 Y R o .15 R T L QUAR 1300 .51 VOLCANIC P 1600 900 .08 P O .17 r OND R 1500 T .13 O O e REGIONAL R. L 1100 k Q U 1000 2 .29 s OLD TUNNEL ROAD SIBLEY P N o DOGS ARE NOT PERMITTED U .41 O D 1000 PRESERVE 1700 C A T c T In this section of parkland. R VOLCANIC O FENCELINE D P M Old Tunnel Road R Private 900 Y 1200 N L .36 FISH RANCH ROAD 1200 REGIONAL PropertyEBMUD O 1000 R Self-guided tour U Staging Area O D O P 1.36 6 parking spots R .29 miles to Fish Ranch Road. PRESERVE begins here. Round Top T NO ACCESS 900 1100 R 1.75 miles to Tilden Reg. Park 1100 See descriptions EBMUD 1,763 A BEYOND GATE I below. 1 L DOGS MUST BE ON LEASH.74 .47 Water Tank from park boundary to Sibley .03 .18 .20 p Creek .18 .08 Sibley staging area on Skyline Bl. nd To Back pack HUCKLEBERRY 800 Rou .02 Wilcox 1200 7 parking spots BA IL Camp .03 .08 BOTANIC Station 800 3 Y ARE TRA .15 1400 To Canyon Road and Moraga S A RIDGE Staging GRIZZLY KYLIN IL 1100 IL REGIONAL E TRA .87 A TERR. DR. R Area T 10 parking spots D K .24 PRESERVE ST ROA 1300 PINEHUR O .22 Separate map available.