UNITED STATES DEPARTMENT OF THE INTERIOR

GEOLOGICAL SURVEY

156° 156°

59°00

BULLETIN 1058 PLATE 29
153°07'

AM ih

59°00"

ee
9
Ss
—| 30"
v
|
EXPLANATION
—_t
i eo
a Qa = ee
~ - = Contact
Tuff Undifferentiated Gi Dashed where approximately located; queried
Deposited during early phase of surficial deposits E where inferred
oa 1912 Mount Katmai eruption Predominantly abevialand | 3 ——
glacial gravel; locally 2
includes ash and pumice Se ae
deposits and beach depos- . F
ite Pleistocene and. Re- Fault, showing relative movement
ey Dashed a eaten located; queried
rn where doubtful. U, upth ide; D,
Voleanic rocks | leon pthrown side,
Chiefly andesite and basalt !
i hee
| —— 74
Igneous rocks, Apple: +15
WEA undifferentiated Sans ‘al
Berita) Locally includes silicie and iiioa tra axial plane and plunge of
Intrusive rocks mafic intrusive rocks amis. Dashed where approximately located;
: 4 queried where inferred
and Kenai formation
equivalent al
Syncline
Showing trace of axial plane. Dashed where
> approximately located; queried where
A & doubtful
=| Coal-bearing rocks Voleanic rocks =
& Probably equivalent to Chiefly andesite and ba- = Vn
Kenai formation salt; locally interfingers sl
with continental sedi- - A
aaah dan or ie Strike and dip of beds
clude some Paleocene Based on field measurement
rocks
We
UNCONFORMITY ) . .
e Strike and approximate dip of beds
< re} Based on interpretation of photographs
8 iS)
<x
: K k formation J if ®
roy aguyal ie Horizontal beds
UNCONFORMITY
2 aaa
: [Ack] Lateral, terminal, and recessional
eS i moraines
Naknek formation
Includes Chisik conglomerate member, Jnch, re)
58° S) at base B J A [58°
2 Location of measured section
LOCATION INDEX . UNCONFORMITY x
156° 154° g a 25283
/ Gs : E 2
: wh e os Location of fossil collection
a ee aes DILLINGHAM LIAMNA e Rs
BS} sys ar .
eee an ie ree 3 Silicic and mafic intrusive rocks
2000
NAKNEK ‘SFOGNAK Reported gas seeps
MT KATMAI
58° 58°
Sedimentary and (or)metamorphic eee a
UGASHIK KARLUK KODIAK rocks, undifferentiated ae
Older than Middle Jurassic
Path of glacier
156" 154°
e
Camp 4
Campsite (1954
57750'e | is Vi : | ) —157°50°
156°15° nas | | i Ba 153°07'
30 155° 30° 154°
$
= :
§ 3 &
t 2 4 i238 '
A FS 6 = a a8 ba 3s 3 Snowy Mountain r
7algeo} . & Mt Ikagluik Knife Peak Volcano Mt Katmai 3 Fy 10.000" 10,000' Be a2 2 10,000'
3 iS ci gz §& s
Een? Bay of Islands = 3 atu El fesriot cena g 5,000! 5,000! £23 Jn & 5,000"
= 5 oe 2 a Ji vt |
Sea level = : Sea level Sea level
: Jnch
5,000" 5,000' 5,000'
10,000" 10,000" 10,000"
i i Unconsolidated deposits not shown
aa Unconsolidated deposits not shown Pee — pe i
2
°
5) < 2
a BS 5 e
Ei 5 3 3 § EB
2 s Fa = 2 2 Fy
¥ 3 = 2 & $
Cc < = s g aC D = & 3 D’
10,000". Fi 2 Z “= [-10,000' 10,000' 3 3 Annee
a
r i = : g : ; s Jn : é Kk :
5,000" 1B x s & 7 5.000 5,000' Jn B S 5,000'

Unconsolidated deposits not shown

20,000°-

Base map by Topographic Division
U.S. Geological Survey, 1951
(with modifications)

GEOLOGIC
Seale 1:250000

5 0) 5 10 15

Unconsolidated deposits not shown

20 Miles

Contour interval 200 feet
Dotted lines represent half-interval contours
Areas not surveyed in detail indicated by broken lines
Datum is mean sea level

1958 magnetic declination at south edge of map area varies from 21° to 22°E

MAP AND STRUCTURE SECTIONS IN THE MOUNT KATMAI AREA, ALASKA

INTERIOR—GEOLOGICAL SURVEY, WASHINGTON. D.C.,

Geology mapped by A. S. Keller and H.N. Reiser,

1954, W. Juhle and R. Kistler, 1953, W. R. Smith,
1923, K. F. Mather, 1923, and R. W. Stone (in W.
W. Atwood, 1911).

Photogeology by A. S. Keller

and H.N. Reiser, 1955

20,000'