HomeMy WebLinkAboutm2168 finalDOUGLAS E. MORAN, INC.
ENGINEERING GEOLOGY
CIVIL ENGINEERING
March 8, 1978
Job No.: 76-81
S. E. Medall & Associates f G
2168 South Hathaway Street
Santa Ana, California 92705
Subject: Supplementary subsurface Exploration /
Tracts Numbered 29053, 34160, and 34161
Diamond Bar Boulevard
Los Angeles, County, California
Gentlemen:
Subsequent to our review of the reported results of your preliminary
investigation of the subject tracts (the subject of our letter dated
February 7, 1978), seven supplementary borings have been made in the
vicinity. The borings have been made to allow for additional obser-
londitions beneath the surface. The purpose of this
tn evaluate the hypothesis that the investi-
de mass so extensive and so much
en recognized in the course
been performed. This
engineering Geology
cends
n9S
r
2-
S. E. Medall & Associates March 8, 1978
Job No.: 76-81
dated March 6, 1978. The other- five borings (numbered 11 through 15)
were made on ridges and slopes within the area that was the subject of
your preliminary investigation. All but one of the borings were entered
and logged in detail by the undersigned engineering geologist. One boring
Numbered 13) was not safe to enter.
A description of the materials and the structural features observed in
each boring was recorded, and a graphic log was prepared to illustrate the
conditions observed. The graphic logs of Borings Numbered 11 through 15
except 13) are submitted with this letter.
All seven of the supplementary borings that were nude encountered firm and
apparently undistrubed bedrock. Only one (Boring Number 12) penetrated
material that could be identified as disturbed bedrock material or landslide
debris. That boring was made in an area that had been recognized as an
ancient landslide during your preliminary investigation. The topography
had suggested sliding, and disturbance of the bedrock material had been
noted in the exploratory excavations made in the area during the preliminary
investigations.
Residual soil and badly weathered rock was present at or near the natural
surface at each boring location. However, the rock became less weatherer
and increasingly hard with depth. The transition from residual soil to
unweathered and hard bedrock at depth was typical and appeared to be a
normal transition. Some of the badly weathered rock material near the
surface showed evidence of having been disturbed by soil creep.
The harder rock encountered at depth was somewhat fractured and jointed, and
a few fractures were open by a fraction of an inch. However, most of the
fractures and joints were widely spaced and 'tightly closed. The hard rock
was essentially intact, and the structure was consistent with recognized
regional trends. The angle of bedding plane dip was generally low.
DOUGLAS E. MORAN, INC. 0 TUSTIN, CALIFORNIA
3_
S. F. Medall & Associates March f3, 'I978
Job No.: 76-81
it is our opinion that the Firm rock that has been encountered at depth in
each of the seven supplementary borings is intact bedrock and that the
structural variations and fractures or joints that have been noted in the
rock are of tectonic origin. No evidence that would tend -to support the
massive landslide hypothesis has been recognized.
Very truly yours,
DOUG AS E. MORAN, INC.
74
Douglas E. Moran
DEM:aa
Encl.: Logs of Borings 11, 12, 14 & 15
DOUGLAS E. MORAN, INC. a TUSTIN, CALIFORNIA
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25
IZE-51DIJAL SOIL: TAN To B124WN SILTY CLAY
Z4 1
Z'5 Z
ZZ 3
SILTSTONE,WEAT1-IERED, RU5T`/ TAN TO LIGHT BROWN, IMINL`/ BEDDED WITH OCCASIONAL
a T"IN SAND BEDS. BEDDING M (oO"E, 32" SE.
z1 4
4" MTi4ICKt,RUST STAINED, TAN 51LTY SAND BEDS OFF SET By S/AALL F2ACT1SRE5.
IS R••IdRi Zc7 NTA L.
w5
SE G
1 INTERBEDDED TAN TO RUSTY BROWN,T€IIN SANDSTONE E 5UALE WITH CALICItE ALONG
r—
FRACTURES FRACTURES
19 b
18 7
BADLY FRACTULZED, DEEPLY HWEATERED ZONE OF /AOTTLED OLIVE GRAY TO RUST`/ TAN
1 I SILTSTONE SAND5TONE. FRAGJAEMTS SURROUNDED BY CAUCNE UP Tr7 VZ" TNICIL,
pApER_IN 'To 3/4' TIAIC14, OLIVE GREEN, TI-IOR000IALY SiIFI RED SLICKEt I51DED SILTY CLAY:
16 9 N fo511E, 10b AIW. MARKED B'Y CALIC"E. SANDSTONE,
LIGHT C A`I, IIIITEKBEDDED lu1TN TNINL`/ LAMINATED GRAY TO R'JSTY BROtVIti! SILTSTz?NE , 15
10 BEDDING: N 30rE, 70 NW. -ME BED IS OFFSET BY A OtGH AMGLE FAULT THAT DIPS 50UT14 "o.
L01V
RNGL.E 5F1EAR ZDNE IAARKED BY CALICIAE : N 800W, 1205. 14
11 f SILT5TONE,
OLIVE TO RUST`! BROWN, INTERBEDDED WIT1•I 3"TO C'TRICK LIG14TGRAY TO TAN VE[Ky FINE RAIALED
SANDSTONE, SAKIDSTONES ARE THORDUGI-ILY l2ACTilRED. TiIE SILTSTnNES Af2E CRUSHED i3
12 J
SLICI
El1I5I DED. 2"
BED OF GRAY BENTONITE- BEDDING' MG50E, leMW SILTSTOi%
LE,TIjIMLY LAIAIMATED GRAY TD TAN IAITERBEDDED WIT" THIN SED5 OF CRO55-SEDDED SAPLDS.
FRf CTURED : AI -100E, 12Q NW. 11
14 SAND5TONE,
LIGHT GRAY, FIAIE GRAINED 600E, 140 NW- 10
q
16 LEN5 OF TRIM" LAMINATED SILTSTONE IIARU,
WELL CEIAE14TED SANDSTONE, RUST-
5TAIMED JOINT: N 45*E, 71'5E OPEEAI
FPACTORE E-kV, SZOS 7
18 1
SIL.TSTONE THINLY LAMINATED WITH INTERBEDDED T"IN SAMOSTONIE BEDS. FIRM TO IdARD. BEDDING AT
THE BASE OF THIS SECTION UNDULATES VE9Y GENTLY, BEDDING' N60'*E, 110W. 6
i9 r• f T"IN, DARL4 GRAY SANDSTONE BED SURROUNDED By •T'NOROUGL101 514c PLED f SUCVUNSIDED BEDS
OF MOTTLE-] GRAY TD RUSH BROWN 51LTSTONE. ATTITUDE
OF PLANE XT BASE OF 514EAR ZOAIE ' N GO"E, 8"TO 90 NW. 520 _ r
DIRECTION OF STRIATION ON TiIE PLANAR SURFACE: N 500W. 4
Z1 J
GRADED BEDS OF T141KILY LAMINATED SILTSTONE 4 SANDSTONE BEDS 3f4" 7O 1 TiISCil,, T1•
IE GRADED BEDS CONSt5T OF T141N ( Yp TO YLI") TTIICK OARV, GRA`/ FINE -GRAINED SAND f
THAT
GRADES RAPIDLY UPWARD IMTD BROWN, RUST-STAIIIIED Tll1NLY LAMINATED SILTSTOIUE, J
HARD VELZY DIFFICULT i0 D0.ILL. BEDDING.
N 55Q E, 12" NW, 2
23 2a
o
z5 2b
27
DOUGLAS
E. MORAN— ' 12791
NEWPORT AV., SUITE - G TUSTIN,
CA., 92580 (714) 544-2215 LOG
OF BORING his 11 SCALE:
1" = 2` jjdhJJOB N° 7b-81 2-24-78
W
W
d
40 p
39 1
38 2
37 3
3b 4
35 5
34 6
33 '1
32 8
3 9
30 10
29 91
Z8 12
17 13
zb 14 -- --
25 15
24 v6
23 17
ZZ 1b
Z1 19
2A w
19 21
18 ZZ
17 Z3
16 2,4
15 Z5
14 Up
13 Z7
12 Z8
11 Z9
10 30
9 31
8 32
7 33
34
5 35
4 36
3 37
Z 38
1 39
0 40
41
RESI DUAL SOIL, DARK BROWN SILTY CLAM.
BECOMING LIGHTER. 12-U5TY BROWN WIT14 DAItK BROWN SPOT5 I CAPILLARY ROOT
OPENImcs.
BECOMES SAND`/ IAICLUDES SMALL FRAGMENTS OF SILT5TONIE c SANDSTOIUE.
FRAGMENtS OF 51LTSTOME j SAN05TOI1IE IN A MATRIX of MOTTL.ED BgOWN TO
W14ITE CRUMBLED SILTSToNIE t CALtcµE.
5TEEPL-I DIPPING TRINLy BEDDED SANDSTONE
BADLY FRACTURED SILTSTONE COATED WITH CALICHE
MOILED, RU5T-STAIMF-D GOUGE ZONE, MARKED By PODS OF CNALK71 VNITE CALI CNE
AND SMALL FRAGMEIUTS OF RUSTY TAN SAWDsroNE i SILT5TONE.
SLIC14ENSIDED FI;ZACTURE : N-5, 3eW; WITH STRIATIONS BEARING N 50'W.
LARGE FRAG/AEAITS OF SANDSTONE f SILTSTONE IIJ A /AATRIX OF GRAY CLAY GOUGE.
GRAY CLAY GOUGE WITH NUMERAUS SHEAR5. ALTITUDE OF 514EARIISG= M 45-*W, 55*KI\V
TO N 75- W, 17 - N.
BROKEN i RE-C.E(AENTED W3STY 51LTSTONE I SANDSTONE FQAGIAEI,ITS IN A MAT -Rix
OF GOUGE.
SOFT GREE*I CLAY GOUGE (SLIDE PLANE AT 3S'
THINL`! LA/AINATED GRADED 5ILT5T0AIE SAMD5TONE 9E135, T14SN( ' TO 8"
TgtCA4,) FIDE-GRA NED,GIZAY 'SANDS GRArDINIC-, QUICKLY UPWARD INTO MI1VLY
LAMINATED GIZAY TO G2AY stZOWN 54LTSTOKLE.,
FRACTURES = N'75'0VV, 72-
6-
5, MIO°E, 83'W
SE001 k,IG AT 38' - N'40° E, 5" MVJ.
BOTTOM OF BORING AT 41'
DOUGLAS E. MORAN
12791 NEWPORT AV. SUITE - G
TUSTI N , CA. , 92680 (714) 544-2215
LOG OF BORING N° 12
SCALE 1= 2' 3dh JOB N°T(o-81 1 2-24-78
I-
Z W
Q0
W
Lu
CL a
r Q
so 0
SANDSTONE, IIIEATMERED FRACTURED %VITH SOIAE INTERBEDDED 514ALE
49 i
48 Z FAULT ZONE: N150E, WSW. ROCK 50=40IJKIDING FAULT NAS BEEM CEMENTING
AND IS HARD. ROOTS ALOMG THE FAULT FRACTURES.
47 3
46 4 SAN05TONE, RUSTY TAN
45 5 FAULT, N-5, 40cE
ti
44 6 J r 51LT'STOME, OLIVE TAN TO BROWN, STAINED WIT" RUST T141NL`/ BEDDED HARD.
INTERBEDDED WITH Tt}IN SAND570NES. THE 5EQUENCE 15 BADLY WEATHERED, QUST-
43 7 STAINED i FRACTURED WITH ROOTS ALOMG FRACTURES.
BEDDING AT 5' . N ZO-W, G' \V; AT :o.5' : %I 40°\V, 140SW. 4Z
S 41
9 SANOSTON E, FIIUE TD MEDIUM -GRAINED, WET li 5EEPI NC6 SFIEARED
CLAY, SEAR SURFACE IS WAVY IKITEaSECT1NG BEDDING AT A LOW ANGLE 40
10 N 40Q W, 14* 5W. TLIINLY
BEDDED SILTSTONE : N 30"W, 14"SW, 34
i SHEAR
ZONE, OLIVE GRAY TO BLUE GIZEEN,TH01Z0UGNLY 5LICKENSIDED WET CLA-/ SURROUNDING
FIZACTURED € BRUkEAI SILTSTONE WITH R0015 FOLLOWIMC, THE FRACTURES 38
12 SHEARS AT TF1E BASE OF THE ZONE, WATER 15 SEEPIP4E. FROM !NE FRACTURES ABOVE. SI1EAiZ
SURFACE, N 1TOW, W NE_ 3
13 SILTSTONE, GRAY TO TAN, T"INLY LAMINATED, FRACTURED. FRACTUIZE5 AV_E VtDI- LY SPACED lr
Tun' tVITN P.USTY STAIIU11116. BEDDING AT IZ' : N-5, 50W. 3(a
14 SILTSTORE. SILT`!, FINE-GRAINED, MA55IVE,M0DEIZATELy CEMENTED HARD. 35 15
SILTSTOMF-, GRAY TD RUSTV BRD VN, T141KILY BEDDED 34 16
33 17
32 1s
4" TRICK, SAND BED, DARK. GRAY. BEDDI AIG: N 550W, 4'0 N. THINLY BEDDED,
GRAY TO DUST`/ BROWN SHALE. SLIGHTLY NAVY, NEAIZLy i-IOR1ZOTAL 31 19 BEDDI
MEY 30 A 29
21 28
ZZ 2'
7 Z3
ZG 24 IEQY
14AP-D,
WELL CEMENTED. ZS Z5 Z4
Z6 r
SILTSTONE BECOMES
MASSIVE
IAARD 2-3 27
22 Z8 21
29 WELL
CEMF ttED)
51 LTSTO NE BED. BED01 AIG IS NAVY N 45 `W, 1 d S\V, 20 30 f
T"I"
LY LAMINATED, 8wowKI siLTSTONE, 1=IZM 6" TLIiCK,GRAy
5A1liD5TONE BED, UlELL C&MEKTED, HARD THINL`/ LAMINATED BR0\\
Kl SILTSTONE IS 3Z 1'
1 33
K 4" _MlC,
CALCAREOUSGRAY5AKIDSTONE 16 34 1
BEDDING: hI-S,
7QW 15 35 -- FIZACTLleE5 :
N BOoW,
82" N il N 150 E, 900 i N SD` W, 58" N 14 3- • SAKDGMNE,
6RAY, FINE TO MEDIUM-GRg1NED 13 37 5ILT5TOKiE,
GRA`l, FINE TD MEDIUM-GRAIA}ED s 4" TUICK
GRA`
I 5ANDSTONE. ' BED 12 38 0=
14, GRAY,
UNWEATIIEIZED, IKJTEQ9EDDED TWN SILTSTOME_ SANDSTONE 11 39 VERYDENSEHARD10Ao9
at s
42 7
43 5
45 4
46 BEDDING :
N 5'D TO 10o
E, GP\V. 3 47 Z
48 44
a So
BOTTOM
OF BORING
AT 50' DOUGLAS E. MORAN .
12791 NEWPORT AV.
SUITE - G TUSTIN, CA., 92680 (
714)'544-2215 LOG of BORING
N° 14. SCALE= 1"=Z'
idh IJOB No76-81 1 2--Z6778
z w
a
a
L
o
460 O
59
S8 2
57 3
5XW 4 r
95 5
54 G •, - !
f-
T .. 53
51 9
so 10 — - -
49 11 -
48 12 `•~
4-1 13
4fo 14
1
4s 1S
44 16 —
43 17
41 19
40 ZO — —
I
39 21 -J
38 zz
3'7 Z3
3G Z4
3s zy
34 Aa
33 ZT
3Z —
3t Z9
30 30 r
Z9 31
r
Z8 32
Z7 33 --
ZG 34 ---
Z.5 3'5
r
Z4 3(o
23
Z2 38
Z1 3q
z0 1)
t9 41
18 42
t
1v 44
15 45
14 4&
13 47
1Z 48
11 49
10 50
4 51
52 =
7 S3
b 54
S SS
3 ^
2 Sg
D (00
5AWD, FINE-Gt?,A1MF-0 IMIEMPEQSED WITH BADLY WEATtlIE -ED SILTSTOAIE BEDS.
51LtSl01Ui<, IHIIULY LAMINAlt-V,GKA`I 10 GKAY-t3RD\VlU WITH RU5T-5TAl&lllUG AL.DAIG J61NT5
FRACTURES. PATE2SPER-SE.D WITH THIN BEDS OF FIMF- SOJO OR SILTY SANDS . THE
5"UEMCE 15 SOMEWNAT WC-ATlAF-ZED, SOFT i MOIST BUT 01JOISTUIZBEQ, 50ME of
TF}E J6tKLT5 AQF- DPELl SLIGPIT12-1 t COUTAIN ROOTS,
BED01 A1G : N 2010 E, 100 mw.
5ANDSTONE, FIIJE TO MEDIUM-GRAI UED, DUSTY 61Z0\VtU.
SILTSTDNI=, T141PJLY LAMINATED, RUSTY TAN, FIRM,
J01Il1Tl A1CG = W 30"W. 90"
SHEAZ Z01JE: AI GOOE, 63" IUW
BF-00tA1G: 140IZIZ0AITAL B13T NAVY_
4!'-MIC-K SANDSTOME BED, WELL CElAF-kFTED, Ft2.ACTURED.
1141NLY LAMlr*)AltV 10 MASSIVE, [ai.Ay ZO GIZAy-SKOWN CLAYEY SIL-TSTOME WIT14 IMTEP--
QEDDED -MIN TAW TO Min, GRAY F1 NE SALAD BED5. BEDDIMC, IS WAVY.
BEDDI MG: Al 15* E, 3"To 40 W. FRACTURE : N 116W, 78'E, N 5"kV, W, 4 N 900E, -1i
0 A1.
FEACTWZES CONTAIN 54VAE GYPSU/A t 5041E Ax2E OPEN SLIGHTLY.
1
SAU05TONE, LIGI"ITGRAY, WELL CFJAENTED.
BEDDIM& IS LIGWTLY FRACTURED € JOIWTE:D, -10ItUT5 i F2ACT012ES Al?E TtG14-F 4 IZU5T
5TA I tV ED,
SA"DSTOME, CWSS-F3EDDE.0, GeAY, VIA F- TD MEDIUM-GOAINEZ, CEMEUTr-D BQIT1-LE.
FR-ACTtJRED, UPACTUI-ES AP_E bPE-M OP- FILLED WITH GYPSU/A.
BI DD! NG Is NAVY BUT NORtZOM VA L
F IZACT1f 2E AI S5",W, 90 p
BED D! MG : 10156 W, 4' TO 5- N
M00E12ATEly CEMEUTFD SANOSTDNE 13MS, FRACTUR-ED, FeQCTUQE5 AM V--ILLE-0
W I TtA GyPS0M.
I 5AU0 TOME, CQ0SS-BF-00E0, $AGE OF TUE SAND t5 A SCOUMD SUtZPACE.
S4NDSTDtUE, WELL LEIA -KITED.
5AWDSTOME, WITU GYPSU/A SEAVA ALOk3G Br-DDtA]G,
FIZACTU 2ES _ M 10'ONV, '77 ° E .
3Fc)nt G-- AI650E, 3"AlE.
Z" TNI CK W 1-M I TE SANID BED.
o" TUIC14 SAk)D t3E0.
19EDD1 MG IS wAvY BUT N0t-IZ0lJTAL.
BOTrC)" OF 6OtztMG Al- 60'
DOUGLAS E. MORAN
12791 NEWPORT AV. SUITE - G
TUSTI N , CA., 92680 (714) 544 -2215
LOG OF 130RANG KIS 15
SCALE; 1"= Z` 1 !ill I JOB N°71--54 1 Z-f-6-79