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Geologic Map of the Lassen Peak, Chaos Crags, And

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U.S. DEPARTMENT OF THE INTERIOR GEOLOGIC INVESTIGATIONS SERIES I–2723 U.S. GEOLOGICAL SURVEY Pamphlet accompanies map 121°30' 121°27'30" 626200 626400 121°35' 121°32'30" 626600 626800 btb CORRELATION OF MAP UNITS 627000 627200 wf22 [Symbols on map in parentheses indicate buried units.Units indicated by magenta brackets have uncertain age relations] p22 or btb p22 or abm wv22 whe or (dlp) or or p17 ch wv22 fh wv22 atu or wv22 ch oa wf22 btb p22 pf22 or abw dlp d19 wv22 atu atu btb abm atu btb atu f19 4483400 dlp btb w19 dlp 4483400 or btb s19 wf22 (atu) wf22 p22 btb p19 dlp d14 ~0.3 ka scj btb fh lh ch (sh) or or whe rcf ccf Holocene sce arp rce cce (mrm) p1 7 scd dlp f19 rcd ccd fh fa arp rcc ccc or rcb ccb 4483200 rca pc 4483200 mrm fa ~1 ka wv22 ~8 ka whe p1 7 arp arp arp the dlp dlp p1 7 tal fr ta oa fa ch tb d14 40°35' trl dlp 40°35' or clp slp ch 27±1 ka ch pc pflp dlp dlp oa tb dlp slp tr or fr fr fa rk 4483000 d14 dlp QUATERNARY oa 35±3 ka abw pfk 35±1 ka 4483000 tr abm fk ch tb slp dlp abm abm 41±1 ka psf rsf dlp oa ch abm d19 pc slp acr fh f19 wf22 dlp dlp oa abm dcr ch tr ch ahm 25±21 ka apr oa slp tr 43±2 ka rkr arp abm atb slp abm r27 dlp tr ch tr abm fa oa ch axe tr oa abm slp tr p22 fh ta bnt re pc arp fh slp pfe 66 4 ka psf ± ta tr atu Pleistocene wv22 arp 4482800 abk bnt rsf tr meh ch sd tb clp 4482800 atb atb ta mrl d19 tb ta mrm rsf pc ch lh rsf pc 199±2 ka psf 193±11 ka rdm bec dlp bnt ch 212±5 ka dr atb abk p1 9 ta slp meh ta 244±10 ka dsh ahm 261±5 ka w19 fh abk rsf wf22 d83 dvc dpl arp 270±18 ka fa tr mrl dum trl (mrl) rsf 297 1 ka ta ± rmz dlp sd amc fr ta dlp (meh) wv22 rsf rsf fh sd ta rl av 313±8 ka dlp ta pfe (sd) pc sd pc rrp 4482600 dlp pc 40°32'30" amc 40°32'30" amc slp pfk 4482600 mrl scj tr abk amc dlp dlp amc pc ta arp (sd) scj wf22 pfe 708±21 ka abm amc amc bnt ch rsf pc atb fh amc btb ch pfe cce ccc ch ch ta av fh tr ch bec fh ta dlp fh wf22 arp pc ch ch amc tr fr scd ch rcf ch wf22 dlp amc rcc rcc sce slp ch ch fh LIST OF MAP UNITS ta rcb ccc rcc dlp rsf All units are Quaternary in age. Symbols on map in parentheses indicate buried units. Initial letter ch rcf wv22 ta rrp slp ch of each map symbol indicates dominant lithology of unit, as follows: abk fh (ch) rmz tb rce fh ta ccc ccf Volcanic units Sedimentary units ch tr ahm dlp ch pc abk b, basalt (<53% SiO ) c, colluvium, including talus dlp ch cce 2 fa pc d83 w19 ta m, mafic andesite (<57% SiO ) f, fluvial deposits, including most alluvium 4482400 tr rcd 2 ch fa ta ch rcc(?) fh tr a, andesite (<63% SiO ) l, lacustrine deposits s19 (arp) s19 2 rcb ta w19 4482400 ch d, dacite (<68% SiO2) o, glacial outwash deposits rcd d83 pfk ta rcd ccd d83 pc ta w19 (ahm) r, rhyodacite (<72% SiO ) and rhyolite s, landslide and avalanche deposits amc ccb wf22 s19 (ta) 2 ta (≥72% SiO ) t, till abk pc abk abk ta fh 2 (sh) p, pyroclastic deposits (pf, pyroclastic-flow w, mudflow and other debris-flow deposits tr d83 whe w19 ta ccb ch (sh) pf22 fh (pfk) wf22 deposits) ta r27 s19 dlp ch ch rkr ta s19 (sh) dlp (tal) HOLOCENE dlp tr rkr ta pc pflp s19 d83 ta ta (ch) w19 rcb dcr w19 p17 Pyroclastic deposit of May and June, 1917, from Lassen Peak ch 626200 rl lh ch d83 wf22 626400 626600 rkr (rkr) ta pfk w19 626800 pflp pfk wv22 Viscous debris-flow deposits of May 22, 1915, from Lassen Peak Base from U.S. Geological Survey, Branch of Astrogeology, 627000 627200 ta ta SCALE 1:2 500 pc rkr wf22 (pfk) Photogrammetry Section, 1988. Compiled on AS11-B1 tr fh 0 0.05 0.10 0.15 0.20 0.25 MILES rkr wf22 pfk p22 Pumice-fall deposit of May 22, 1915, from Lassen Peak analytical stereoplotter using U.S. Department of Agriculture tr rca fk color aerial photographs 1673-089 and 1673-090 taken August ta ta pkf 0 0.05 0.10 0.15 0.20 0.25 KILOMETERS ta wv22 28, 1973 (Project LA02-06089). Control points obtained from d83 rrk wf22 Fluid debris-flow deposits of May 22, 1915, from pyroclastic flow ch pf22 1:24,000 Lassen Peak and Reading Peak quadrangles. Grid is ta rkr (ta) ta pf22 fk CONTOUR INTERVALS 2 (ABOVE 3100) AND 5 (BELOW 3100) METERS rl pc d83 rkr tr ta UTM of zone 10. ccb pc (t r) (abk) rdm pf22 Pyroclastic-flow deposit of May 22, 1915, from Lassen Peak dcr pflp fh fh (dcr) d38 d83 wf22 (rdm) d19 Dacite flow of May 19-20, 1915, on Lassen Peak dum rkr ch GEOLOGIC MAP OF THE LASSEN PEAK SUMMIT AREA pc d83 d83 pc r2 7 pflp pf22 fh whe f19 Flood deposits of May 19-20, 1915, in Hat Creek pf22 fh rdm rl ch (ch) rkr pf22 dum (r27) r27 pc (ch) w19 Debris-flow deposits of May 19-20, 1915, from avalanche deposit acr (tal) w19 (ch) pc pfk Pyroclastic-flow deposit of Kings Creek Contact rsf rkr pc pflp —Contacts shown within unit indicate contacts between separate pc (r27) (s19) ta r27 (ch) ch (ta) s19 Avalanche deposit of May 19, 1915, from Lassen Peak volcanic domes whe pflp fk Sediments beneath pyroclastic-flow deposit of Kings Creek dum wf22 ta (pfk) p19 Pyroclastic deposit of May 19, 1915, on Lassen Peak Certain (whe) pf22 (pfk) pc (clp) pf22 psf Pyroclastic-flow and proximal fall deposits of Sunflower Flat rl clp wf22 whe ta Approximately located (whe) r27 ch d14 Dacite dome of May 14-19, 1915, on Lassen Peak dpl ch pf22 40°30' rsf Rhyodacite domes of Sunflower Flat Inferred p22 wv22 40°30' wf22 scj Avalanche deposits of Chaos Jumbles, from dome C of Chaos Crags wf22 pfk Concealed 121°30' ch wv22 whe p22 ahm Andesite flow of Hat Mountain clp wf22 pf22 wv22 p22 (tal) rcf Rhyodacite dome F of Chaos Crags Bear Wallow Butte (dlp) Fault—Bar and ball on downthrown side Chaos Jumbles avalanche deposits dlp p22 acr Andesite scoria deposit on west rim of Crescent Crater ch ccf Talus, emplaced hot from dome F of Chaos Crags Certain Lassen dacitic dome field ta wv22 clp p22 tal dr dcr Dacite dome and flow of Crescent Crater Approximately located 1915 dacitic flow and dome (historic) ch the sce Avalanche deposit from partial collapse of dome E of Chaos Crags ch fh clp rkr Rhyodacite dome and flow of Krummholz Younger prehistoric dacitic domes dlp whe Concealed clp dlp rce Rhyodacite dome E of Chaos Crags (clp) rk Twin Bridges p22 ta r27 Rhyodacite flow of Section 27 on north flank of Lassen Peak Flow direction of landslide Older dacitic domes ch e k p1 7 H a t C r e e k ch cce Talus, emplaced hot from dome E of Chaos Crags r e dlp Vent of unnamed dacitic dome C d14 Moraine crest t clp axe Andesitic mixed lava of Eagle Peak s Map Area o ch p22 clp scd Avalanche deposit from partial collapse of dome D of Chaos Crags Vent of named dacitic dome L dlp Concealed moraine crest dlp re Rhyodacite dome and flow of Eagle Peak dlp ta dvc clp p1 9 rcd Rhyodacite dome D of Chaos Crags Crater rim clp clp pfe wv22 d19 ch Pyroclastic-flow deposit of Eagle Peak ch fh ccd Talus, emplaced hot from dome D of Chaos Crags Concealed crater rim fh sd Highway 44 dlp Avalanche deposit from dacite older than pyroclastic-flow deposits of dlp wv22 dlp tal Red Lake ta rcc Rhyodacite dome C of Chaos Crags Eagle Peak Volcanic vent Badger wv22 wv22 clp Mountain Red tal Mountain Mountain fh tal atu Andesite flow of Tumble Buttes older than Bear Wallow Butte ccc Talus, emplaced hot from dome C of Chaos Crags Concealed volcanic vent fh dlp clp ch ch ch dlp meh Mafic andesite flow of Eskimo Hill Lateral limits of tree destruction by snow-laden pyroclastic flow of May Table the tal rcb Rhyodacite dome B of Chaos Crags Eskimo dlp M Mountain LASSEN VOLCANIC NATIONAL PARK ch re Hill ch 22, 1915 a n z a n i t a C h u t e tal tal dlp mrl Mafic andesite flows of Red Lake Mountain ccb Talus, emplaced hot from dome B of Chaos Crags Lateral limits of snow and hot-debris avalanche of May 19-20, 1915 Sunflower Flat ch rk mrm Mafic andesite flow of Red Mountain ch ch ch rca Rhyodacite dome A of Chaos Crags clp 122° 121° 120° Chaos tb Till of Badger Mountain ta Jumbles pc Pumiceous pyroclastic-flow and fall deposits of Chaos Crags 42° OREGON dvc Dorris Tulelake Anklin ch Meadows Raker fh CALIFORNIA C r e e k M k whe Debris-flow deposits from the northeast side of Lassen Peak a n a L Peak e MIDDLE PLEISTOCENE a n z i t a Manzanita n e M o r Lake z s dpl a t C n CENTRAL PLATEAU ch the Till or protalus-rampart debris of early Holocene age C Emigrant axe dsh rdm Rhyodacite flow of Dersch Meadows i t t r 97 395 Deep e Pass a a e Hole k H pfe fh Fluvial deposits of Holocene age bec Tholeiitic basalt flow of Eagle Canyon C A S C A D E R A N G E 139 C Chaos LOCATION OF GEOLOGIC MAP OF r e Crags THE LASSEN PEAK SUMMIT AREA MODOC e lh Hill 7241 k Crescent Hat Mountain Lacustrine deposits of Holocene age dr Dacite domes of Reading Peak Hill SISKIYOU COUNTY Crater 299 8283 Dersch COUNTY ch Colluvium and talus of Holocene age evastated Area dsh Dacite dome of Ski Heil Peak Alturas Hill 6924 D 299 40°30' Meadows Weed (sh) Landslide deposits of Holocene age—Buried unit only bnt Tholeiitic basalt flow of Nobles Trail 1915 flow Loomis Lassen B a i l e y and dome Paradise Mount Shasta C r Peak Peak e e Meadows dvc Dacite dome of Vulcans Castle McCloud k LATE PLEISTOCENE 89 Dunsmuir Eagle dpl Dacite flow of Lassen Peak Trail Parking Lot Vulcans Peak tal 5 Castle Late till of Anklin Meadows PARKING Reading d83 Dacite dome and flow of hill 8283 LOT 299 Peak 121°35' 121°32'30" 121°30' 121°27'30" INTERIOR—GEOLOGICAL SURVEY, RESTON, VA—2002 ta Till of Anklin Meadows Ski Heil Kings Creek k 16 1/ SHASTA Park Road e 2° SCALE 1:24 000 41° Mt.
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    Index [Italic page numbers indicate major references] Abajo Mountains, 382, 388 Amargosa River, 285, 309, 311, 322, Arkansas River, 443, 456, 461, 515, Abort Lake, 283 337, 341, 342 516, 521, 540, 541, 550, 556, Abies, 21, 25 Amarillo, Texas, 482 559, 560, 561 Abra, 587 Amarillo-Wichita uplift, 504, 507, Arkansas River valley, 512, 531, 540 Absaroka Range, 409 508 Arlington volcanic field, 358 Acer, 21, 23, 24 Amasas Back, 387 Aromas dune field, 181 Acoma-Zuni scction, 374, 379, 391 Ambrose tenace, 522, 523 Aromas Red Sand, 180 stream evolution patterns, 391 Ambrosia, 21, 24 Arroyo Colorado, 395 Aden Crater, 368 American Falls Lava Beds, 275, 276 Arroyo Seco unit, 176 Afton Canyon, 334, 341 American Falls Reservoir, 275, 276 Artemisia, 21, 24 Afton interglacial age, 29 American River, 36, 165, 173 Ascension Parish, Louisana, 567 aggradation, 167, 176, 182, 226, 237, amino acid ash, 81, 118, 134, 244, 430 323, 336, 355, 357, 390, 413, geochronology, 65, 68 basaltic, 85 443, 451, 552, 613 ratios, 65 beds, 127,129 glaciofluvial, 423 aminostratigraphy, 66 clays, 451 Piedmont, 345 Amity area, 162 clouds, 95 aggregate, 181 Anadara, 587 flows, 75, 121 discharge, 277 Anastasia Formation, 602, 642, 647 layer, 10, 117 Agua Fria Peak area, 489 Anastasia Island, 602 rhyolitic, 170 Agua Fria River, 357 Anchor Silt, 188, 198, 199 volcanic, 54, 85, 98, 117, 129, Airport bench, 421, 423 Anderson coal, 448 243, 276, 295, 396, 409, 412, Alabama coastal plain, 594 Anderson Pond, 617, 618 509, 520 Alamosa Basin, 366 andesite, 75, 80, 489 Ash Flat, 364 Alamosa
  • Sampling of Great Year Round Attractions Found in Redding and Shasta Cascade

    Sampling of Great Year Round Attractions Found in Redding and Shasta Cascade

    SAMPLING OF GREAT YEAR ROUND ATTRACTIONS FOUND IN REDDING AND SHASTA CASCADE Any Adventure, Any Day awaits those who visit Redding and Shasta Cascade. Whether your idea of a great vacation means extreme outdoor adventure, family-friendly activities, or cultural excursions, Redding and Shasta Cascade are filled with year-round unexpected pleasures. Land lovers can explore Redding through its expansive and nationally-recognized trails system, where visitors walk, hike, bike, or horseback ride their way to adventure. If you prefer playing in the water or floating on top, Redding’s access to several rivers and lakes allows for boating, paddle-boarding, rafting, swimming, and fishing on the Sacramento River, or at nearby Whiskeytown and Shasta Lakes. There are so many great things to do and see all year long in this breathtaking region, you’ll soon understand why visitors come back again and again. SUNDIAL BRIDGE This one-of-a-kind, glass decked pedestrian bridge serves as an incredible entrance to Redding’s Sacramento River National Recreation Trail. World-renowned Spanish architect, Santiago Calatrava, conceived the unique design of the bridge. It is the first bridge of its kind in the United States, and is the tallest working sundial in the world! The massive 217 foot pylon leans due north and functions as the gnomon of a sundial, casting its giant shadow on a garden- bordered dial plate at the bridge’s north end. The suspension, cable-stayed design of the bridge does not have any footings in the river, out of respect for the nearby salmon-spawning habitat. Receptions under the bridge are available.
  • Geologic Map of Lassen Volcanic National Park and Vicinity, California by Michael A

    Geologic Map of Lassen Volcanic National Park and Vicinity, California by Michael A

    Geologic Map of Lassen Volcanic National Park and Vicinity, California By Michael A. Clynne and L.J. Patrick Muffler Pamphlet to accompany Scientific Investigations Map 2899 Lassen Peak and the Devastated Area Aerial view of Lassen Peak and the proximal Devastated Area looking south. Area with sparse trees marks the paths of the avalanche and debris-flow deposits of May 19–20, 1915 (unitsw9 ) and the pyroclastic-flow and fluid debris-flow deposits of May 22, 1915 (unit pw2) (Clynne and others, 1999; Christiansen and others, 2002). Small dark crags just to right of the summit are remnants of the May 19–20, 1915, lava flow (unitd9 ). The composite dacite dome of Lassen Peak (unit dl, 27±1 ka) dominates the upper part of the view. Lithic pyroclastic-flow deposit (unitpfl ) from partial collapse of the dome of Lassen Peak is exposed in the canyon of the headwaters of Lost Creek in center of view. Ridges flanking central area are glacial moraines (unitQta ) thinly covered by deposits of the 1915 eruption of Lassen Peak (Christiansen and others, 2002). Small permanent snowfield is seen on the left lower slope of Lassen Peak. Area east of the snowfield is the rhyodacite lava flow of Kings Creek (unitrk , 35±1 ka, part of the Eagle Peak sequence). Dacite domes of Bumpass Mountain (unit db, 232±8 ka), Crescent Crater (unit dc, 236±1 ka), hill 8283 (unit d82, 261±5 ka), and Loomis Peak (unit rlm, ~300 ka) are part of the Bumpass sequence. Photograph by Michael A. Clynne. 2010 U.S. Department of the Interior U.S.
  • LAVO Summer Guide 2020

    LAVO Summer Guide 2020

    National Park Service U.S. Department of the Interior Lassen Volcanic Guide Lassen Volcanic National Park Summer/Fall 2020 Be Prepared for Modifications to Services and Facilities Learn more about how Lassen Volcanic National Park is responding to COVID-19 and how you can recreate responsibly on page 13. Explore Your Park in... Four Hours One Day Two or More Days Half a day is just enough to enjoy A full day gives you time to enjoy More time provides the opportunity to several Highway Highlights multiple Highway Highlights enjoy longer hikes and a full day in one (pg 3) along the 30-mile road (pg 3) and at least one hike in the of the more remote areas of the park. that connects the northwest and Southwest or Manzanita Lake areas. southwest entrances. Plan one Hike Cinder Cone (pg 8) and marvel hour drive time without stops. Take a hike (pg 8-9). The most at the Painted Dunes and lava rock- popular trails in the park offer a lined Butte Lake. Take in the sights, sounds, variety of sights and experiences: and smells of Sulphur Works Lassen Peak (5 mi), Bumpass Hell Climb to the active fire lookout Hydrothermal area (pg 3). (3 mi), Kings Creek Falls (3 mi), atop Mt. Harkness (pg 9) and take a and Manzanita Lake Loop (1.8 mi). refreshing dip in Juniper Lake. Hike the Devastated Area Parking is limited: arrive early; go Interpretive Trail (pg 8) and uncover the dramatic story of the mid-week; or choose an equally Explore a remote hydrothermal area 1914-1915 Lassen Peak eruptions.