INDEX
A
Abbot, C., 14
Acknowledgments, VII
Aerosols, sulfur dioxide, 14 , 16 , 19
Agung:
cold wave preceding, 21 ;
floods, record tornadoes, and unusual storms following, 21
Alligator Head, collapse of arch at, 134 –135
Alluvial cliffs, 5 ;
periodic erosion of, 120 –127;
recent construction of concrete seawall along, 125 ;
renewed erosion of, 122 –127;
some unusual methods to stop erosion of, 122 –125
Anderson, Andy, 114
Arch, 10 ;
change in, 150 , 152 –153;
collapse of, 134 –135;
collapse of Cathedral Rock, 138 –139;
collapse of Windansea Rock, 139 –141;
little change in, 118 , 132
Arizona, destructive floods during February 1891 in, 34 , 36
Atcheson, Topeka and Santa Fe Company:
relocation of coastal route at Del Mar by, 102 –103, 105 ;
trains crashing to the beach during storms, 103
Averaged lowest volcanic periods, tables showing comparison with posteruptive periods and, 25
B
Bada, J., 127
Ballast Point (Punta de los Guijarros; Cobblestone Point), 155 ;
first smog in San Diego at, 155
Bandai San volcano, 22
Barrier beaches, 5 , 127 , 143
Bathtub Rock, 110 –111
Batiquitos Lagoon, artificial opening of, 4
Bear Valley, north of San Diego, record rainfall of February 1891 at, 36
Berggreen, R., 43
Big cone spruce trees, tree rings from, 12
Bird Rock, cliff collapse of, 141
Blacks Beach:
landslides along, 112 –113;
removal of talus debris by storms in December 1940 at, 112
Boomer Beach, seasonal changes at, 136 –137
Brewer, W., 31
C
California, destructive floods during February 1891 in, 34 ;
great 1862 flood in, 32
California Coastal Commission, 121
California Southern Railroad:
bankruptcy in 1884 of, 3 ;
1889 mining of cobbles at barrier across Penasquitos Lagoon by, 109 ;
surveys between 1880–1891 along, 70
Campo, east of San Diego, world record rainfall 12 August 1891 at, 36
Camp Pendleton, 5 ;
construction of military harbor at, 55
Cape Horn, comparison of severe storm with those reported along Southern California with, 29
Cardiff-by-the-Sea:
collapse of highway 101 at, 92 –93;
location of, 68 ;
1983 damage to restaurants by waves, cobbles and riprap at, 94 –95;
precarious existence of restaurant row at, 94 –95;
riprap rock scattered by waves at, 92 –93
Cardiff State Park, erosion of cliff around stairways at, 85
Carlsbad:
failure of sand to return to beach during summer of 1980 at, 62 ;
location of, 50 ;
1983 destruction of restroom facilities by waves at, 67 ;
1983 rapid beach erosion at, 66 –67;
nonmarine terrace at, 51 ;
storm drain collapse and erosion of bluffs at, 64 –65
Carlsbad Submarine Canyon, 41 ;
interception of sand by, 63
Casa Pool (Childrens Pool), La Jolla, inadequate jetty construction at, 137 ;
recent storm effects at, 137
Cathedral Rock, collapse of, 138 –139
Catholic Missions, records of, 14
Caves:
collapse of, 150 ;
deep reentry, 118 –119;
recent, 10
Caves and Sea Arches, formation and collapse of, 71 –81
Chile, El Niño along, 19 ;
abnormally warm water along, 20
China, great flood during 1982 in, 18
Christianitos Fault, near the San Onofre nuclear power plant, 43
Chubascos, windstorms largely centered along northwest Mexico called, 29
Climate change, 13
Coastal area description, 3
Coastal cliffs and canyon erosion, nature of, 44 –46
Coastal history, description of in geographical sequence, 39 –164
Cobble abrasion:
damage to buildings as a result of, 94 –95;
damage to highway by, 108 –109;
1983 erosion of bluffs at Scripps Institution of Oceanography by, 125 ;
observed enlargement and collapse by, 78 –79;
rapid erosion of sea caves by, 76 –78;
recent damage at Oceanside by, 59 –61
Cobble barrier:
description of, 109 ;
mining of, 109 ;
1983 destruction of coastal highway by, 108 –109
Cobble Beaches, 56 –57;
movement of, 59 –62, 76 –78, 94 –95
Collapse of Highway 101 at Cardiff-by-the-Sea, 92 –93
Colorado, record snowstorm of 1982 in, 19
Conclusions, 165 –168
Conclusions concerning characteristics of pre-volcanic, post-volcanic, and low-volcanic periods, 28
Concretionary rock forming a dike, 127
Construction of bluff tops, 71 –76
Converse, Davis and Associates, 43
Coronado and Imperial Beach, 156 –164;
location of, 156
Coronado Islands, U.S., 5 ;
location of, 156 ;
longshore currents of, 6 ;
history of, 157
Coroner reports, county, 10
Cottonwood Creek, Encinitas (Moonlight Beach), erosion at mouth of, 34
County tax assessor, records of, 10 , 34
Cove beaches, coarse sand derived from local sandstones as source of, 119
Crown Point, 143
Cuyamaca, record rainfall of February 1891 at, 36
D
Dana Point, 41
Dana, R., 29
Dangerous location of U.S. Fisheries and Wildlife building and Scripps IGPP building, 114 –115
Data Analysis, 24
Dead Dog Canyon, Camp Pendleton, rapid canyon cutting at, 49
Del Mar:
alteration of bluff by railroad at, 102 –103;
coastal canyon erosion and lagoon siltation at, 102 –103;
destruction of sand-filled tube on the beach at, 101 ;
extensive erosion of beach in 1978 and 1980 at, 100 –101;
glass-enclosed wading pool constructed at foot of 10th Street in, 100 –101;
iron oxide surface cementation of terrace sands at, 97 ;
location of, 97 ;
1983 storm damage along, 101 ;
1979 summer cliff failures as a result of groundwater at, 104 –105;
relocation of railroad at, 101 –102, 105 ;
replenishment of beach sand at, 101 ;
sand transport direction change at, 101
Derby, G., 147
E
Earthquakes, documentation of, 11
Earth's temperature, lowering of, 14
Eastern Pacific Ocean, abnormally warm water along, 20
Ehlig, P., 43
El Capitan Dam, 147
El Chichon:
cold wave preceding, 20 ;
eruption of Mexican volcano, 16 ;
record tornadoes following eruption of, 21
Ellen Scripps, 111
El Niños, fish fauna changes during, 20 ;
great ones following major volcanic eruptions, 20
Emery, K., IX , 10 , 12 , 57 , 127
Encinitas, California:
attempt to reprovision settlers at, 33 ;
coastal changes at, 35 ;
destruction along old Cottonwood Creek (Moonlight Beach) at, 70 ;
flooding near, 33 ;
location of, 68 ;
purchase of land at, 70 ;
record rain on 12 October 1889 at, 34 , 70 ;
stairway collapse in 1978 at, 82 –85
Erosion acceleration caused by man, 46 –49
Explosive volcanic eruptions, weather alterations from, 14 –28
F
False Bay. See Mission Bay
Fish Fauna changes due to El Niños, 20
Flood Period:
of 1884–1891, 32 –37;
of 1916, 37 –38;
1862, 31 –32
Floods, documentation of, 11 , 31 –38
Frautschy, J., 115
French Polynesia, great hurricanes of 1982 in, 19
Fugro, Inc., 43
G
Goldfish Point, arch at, 118 , 132
Great flood period of 1862, 31 –32
Great floods of nineteenth century, 31 –37
Great waves off Southern California in 1830's compared with those off Cape Horn, 29
Great windstorms of the nineteenth century, 29
Greene, G., 43
Griggs, R., 14
Groundwater table:
blockfalls caused by rise in, 72 ;
causes of rise in, 71 ;
importance of, 71 ;
landslide caused by rise in, 72 ;
rise in, 71 , 87
Gulf of Alaska, abnormally warm water along, 20
H
Hales, L., 52 , 55
Hanna, M., 115 , 121
Hannan, D., 127
Hardy, W., 21
Hatfield, C., extraordinary rainmaker, 38
Hayes, B., 109
Hayes, J., 31 , 145
Hidden Valley, old lagoon at mouth of, 117 , 126
Highway 101, alteration of drainage patterns due to installation of culverts under, 46
Honshu, Japan, great flood of 1982 in, 18
Horno Canyon, Camp Pendleton, rapid erosion at, 47
Hotel Del Coronado:
construction of, 159 ;
rapid erosion along ocean boulevard at, 159 –160;
recent construction of large condominiums south of, 156 , 161
Humphreys, W., 14
Hunt, G., 43
Huntington Beach, California, flood of 1862 at, 32
Huntington, E., 14
I
Imperial Beach, artificial nourishing of beach by dredging at, 163 ;
erosion of, 163 –164;
longshore currents of, 6
Infrequent floods of the early twentieth century, 37
Inman, D., 40 , 53 , 55 , 157 , 162 –163
Institute of Geophysics and Planetary Physics (IGPP), 115
International border between United States and Mexico, 157
Interstate highway #5, alteration of drainage patterns due to installation of culverts under, 46
J
Judge, Hayes, Benjamin, description of great cobble barrier across mouth of Penasquitos Lagoon given by, 109
Junipero Serra, San Diego founded by, 144
K
Katmai volcano:
drop in temperature, increase in storminess with arrival of dry fog follow eruption of, 22 ;
further unseasonable alternation of warm and cold periods following eruption of, 22 ;
record cold weather preceding, 22 ;
worldwide dry fog (haze) reported almost immediately following eruption of, 27 ;
year without a summer following eruption of, 22
Kauai, Hawaii, great hurricane in 1982 along, 18
Kennedy, M., 43 , 149
Kentucky, floods of 1982 in, 18
Kimball, H., 22
Krakatoa volcano:
cold and stormy period preceding eruption of, 23 ;
great floods in lower Mississippi Valley following eruption of, 24 ;
great floods in Southern California following eruption of, 24 ;
record tornadoes following eruption of, 24 ;
summer killing frost reported following eruption of, 24 ;
unusual sunsets following eruption of, 23 ;
weather conditions following, 15 , 70
L
La Jolla, 10 , 107 ;
possible solution origin of sandstone caves at, 132 ;
sea surface at, 12 , 116 –118;
wave cut terrace at, 116 –117, 131
La Jolla Beach and Tennis Club, 117
La Jolla Cove, 119 ;
concretions near, 133 , 135
La Jolla Farms area, drell landslide along, 113
La Jolla Shores, 127 –128
La Jolla submarine canyon, 128 –129
La Jolla Terrace, 143
Lamb, H., 14
La Nacion Fault, 109
Le Comte, D., 20
Lee, L., IX
Legg, M., 43
Leighton and Associates, 112
Leucadia:
cave roof collapse at, 77 ;
formation of caves at, 77 ;
location of, 68 ;
loss of stairways at, 82 –83;
rapid erosion of cliff in 1983 at, 77
Leucadia South through Solana Beach, 69 –95;
description of area along, 69
Libby and Associates, 79
Literature:
historical, 11 ;
scientific, 11
Littoral cells, in relation to submarine canyons along Southern California coast, 10
Location map:
area of Coronado and Imperial Beach shown on, 156 ;
area of Del Mar and vicinity shown on, 96 ;
area of Leucadia, Encinitas, Cardiff-by-the-Sea and Solana Beach
shown on, 62 ;
area of Ocean Beach, Sunset Cliffs, and Point Loma shown on, 148 ;
area of Pacific Beach, Mission Beach, San Diego Bay and river shown on, 142 ;
area of San Onofre State Park and Camp Pendleton shown on, 42 ;
area of Santa Margarita River south through Oceanside and Carlsbad shown on, 50 ;
area of Sorrento Valley South through North La Jolla shown on, 106 ;
area of study shown on, 1
Logs of vessels, sea storms recorded in, 11 , 14
Longshore currents, 5 , 63 , 163
Longshore transport direction, 49 , 163
Los Angeles Plains, extensive flooding in 1862 of, 31
Los Angeles River, merging in 1862 of, 32
Lower Otay Dam, San Diego, break in January 1916 of, 38
Low volcanic periods, 17 , 27
Ludlum, D., 20
M
McGlashan, H., 32 , 38 , 99
Marine advisors, 55
Marine Biology Building, Scripps Institution of Oceanography:
concrete seawall constructed in front of, 127 ;
erosion under, 127
Marine Room Restaurant, damage by storms at, 128 –129
Marine Street, La Jolla, erosion by large waves at, 141
Mass, C., 17
Masters, P., 109 , 111
Mauna Loa Observatory, observation of gases from El Chichon Volcano at, 16
Methods of study, 9
Mission Bay, 143 ;
changes in, 144 –145, 147 ;
former name "False Bay," 144 ;
former use for sea–going vessels in, 144 ;
jetties constructed at, 147
Mission Beach, 143 ;
changes in, 144
Mission San Diego de Alcala, 144
Mission Valley, San Diego:
floods of, 31 ;
flood of February 1891 in, 36 ;
great flood in 1916 at, 38
Mississippi Valley, major flood of 1982 in, 19
Moore, G., 114 –115
Mount Soledad:
fault at base of, 7 ;
Rose Canyon fault scarp continuation of, 131 –132
Multi-eruptions of the late 1880's:
curious relationships of abrupt weather changes to, 23 ;
record violent windstorms, floods, and tornadoes following, 23
N
National Marine Fisheries, 114 –115;
landslides at, 114 –115;
seaward movement of landslide related to distant earthquakes at, 115
Nature of coastal cliffs and canyon erosion, 44
Net longshore drift, showing balancing of, 49
Newport, California, damage by great tropical storm at, 29 –30
Newton, C., 44
"Noachian Deluge," great flood of 1862 called, 31 , 147
Northeastern United States, cold weather conditions following 1815 Tambora eruption reported in, 15
Northern San Diego County:
cliff stairway collapse along, 19 ;
rapid retreat along, 19 ;
sea cave formation along, 19
O
Oceanside, California, 5 , 10 , 150 ;
aerial view showing decrease of beach width south of harbor at, 54 ;
beach cobbles thrown by waves against houses at, 59 –61, 150 ;
change in direction of longshore currents at, 63 ;
collapse of beach road at, 58 –59;
construction of city harbor at, 55 ;
construction of military harbor directly north of, 55 ;
damage to houses in 1940–1941 at, 52 –53;
development and destruction of coastal wharf at, 52 ;
location of, 50 ;
loss of beaches due to harbor construction at, 55 ;
movement of cobbles along beach at, 61 ;
recreational pier at, 52 ;
subaerial erosion of cliffs at, 50 –51;
30 foot terrace at, 51 ;
wide beach at, 50 –51
Oceanside littoral cell, location of, 40 –41
Old charts, 10
Old coastal changes, 35 , 70 –71
Old land surveys, 10
Old railroad surveys, 10
Old Town (San Diego), 143 ;
flooding at, 147
P
Pacific Beach and Mission Beach, San Diego Bay and River, 143 –147
Palomar Mountain, 1884 cloudburst at, 33
Penasquitos Lagoon, 107
Peru, El Niño along, 19
Phillips, D., 20
Phreatic eruptions, major, showing comparison of six-month period preceding, 26
Point La Jolla, 3 , 5 , 29 , 114 , 117 ;
deeply penetrating caves at, 118 , 132 ;
sea arches and stacks at, 132
Point Loma, 143 , 147 , 149 , 155 ;
location of, 148
Port San Luis, sea cliff at, 8 –9, 11
Post, J., 15
Post-volcanic periods, 17
Pourade, R., 38 , 144 , 147
Punta de los Guijarros. See Ballast Point
R
Rainfall, documentation of, 11 ;
Julian, 12
Rampino, M., 14
Revelle, R., 141
Rip currents, 130 –131
Rodrequis Flood Control Dam, 163
Rodriquez Cabrillo, 144
Rose Canyon Fault Zone, 131
Rose, W., 16 –17
S
Sacramento, California, submerged in 1862 floodwaters in, 31
Sacramento Valley, California, great flood of 1862 in, 31
Saint, P., 89 –91
San Bernardino, 1884 flooding of railroad line at, 33
Sand bars, formation by rapid canyon cutting and, 48 –49
San Diego:
flood of 1884 in, 33 , 70 , 144 ;
flood of 1862 in, 32 , 144 ;
great flood of 1916 at, 38 ;
history of, 144 ;
minor flood of 20th century at, 38 ;
record rainfall at, 34
San Diego Bay, 5 , 157 , 164
San Diego County:
climate changes in, 13 ;
great storms reported along, 15 ;
record flood of, 15 ;
record rainfall in, 19 ;
record rainfall levels in, 32 –33;
report of storms in, 33 ;
warm water along, 20
San Diego County Tax Assessor records, showing changes in value between 1889–1890 during stormy period in, 34 –35, 70
San Diego Harbor:
dredging of, 159 ;
erosion and stabilization of entrance at, 159 ;
history of, 144 –146;
new channel cut in 1862 at, 32
San Diego Herald, 147
San Diego River, changes at mouth of, 144 ;
delta of, 142 –143, 147 , 149 ;
El Capitan Dam constructed on, 147 ;
flood of 1884, 1889, and 1891 on, 144 ;
flood of 1862 on, 31 –32, 144 ;
jetties constructed at mouth of, 147 –149
San Diego Union, flood of 1884 reported in, 109 ;
report of cloudburst in, 33
San Diegueno Indians, 109
San Dieguito River Flood Plain, 98 –100;
dams located above, 98 –99;
Del Mar Race Track located on, 98 –99;
1938 flood along, 99 ;
1980 flood along, 98 –99
Sand return failure to beaches during summer 1980, 63 –67
Sandstone caves, possible solution origin of, 132
San Francisco, 31
San Gabriel River, merging in 1862 of, 32
San Joaquin Valley, California, great flood of 1862 in, 31
San Luis Rey River, Oceanside, 51 ;
cobbles derived from floods of, 55 ;
Lake Henshaw dam along, 52
San Onofre, 5 ;
debris fans at, 46 ;
formation of sand bars at, 49 ;
1941 landslide at, 44 –45;
1978 landslide at, 45 ;
nuclear power plant at, 41 ;
rapid canyon cutting at, 47 –48;
state park at, 41 ;
unusual formation of beach during winter 1983 at, 48
San Onofre and Camp Pendleton area, 41 –49;
location of, 42
Santa Ana River, merging in 1862 of, 32
Santa Barbara Basin, varves of, 12
Santa Barbara, California, great coastal flood of 1862 at, 31
Santa Catalina Island, 33
Santa Margarita Ranch, Oceanside, extremely heavy rainfall at, 33
Santa Margarita River, Oceanside, 51
Santa Margarita River South through Oceanside and Carlsbad, 51 –67
Scripps Institution of Oceanography, 5 , 112 , 114 , 129 ;
alluvial cliffs near, 121 –127;
erosion of rock platform between 1940–1979 north of, 130 –131;
Institute of Geophysics and Planetary Physics at, 115 ;
precarious location of Marine Biology Building at, 126 –127;
unprotected section of cliff at, 125
Scripps submarine canyon, 128 –129
SCT Consultants, 113
Sea Cave, 5 , 10
Self Realization Fellowship, Encinitas:
collapse of temple at, 86 –87;
erosion history of, 87 –91;
groundwater level rise at, 87 ;
1980 landslide as a result of grading the bluff at, 90 –91;
1978 landslide at, 88 –89;
sheet plastic placed on bluff face to slow erosion at, 91 ;
subsurface groundwater movement at, 90
Seymore, R., 49
Shaw, M., 55 , 159
Shepardson Engineering Associates, 79
Shumway, G., 127
Siberia:
1979 record cold before Soufriere in, 20 ;
warm weather following Tambora in, 15
Signal Hill, California, flood of 1862 at, 32
Silver Strand Littoral Cell, 157 , 162 ;
accretion area along, 157 ;
location of, 6 , 162 ;
source of sediment along, 157
Simkin, T., 20 –21
Smithsonian Institution, 24
Solana Beach:
damage to stairway at, 85 ;
development and collapse of an arch in a few days at, 80 –81;
location of, 68 ;
possible solution origin of sandstone caves at, 132 ;
stairway that survived 1983 storms at, 84
Solana Beach (South):
caves of, 10 ;
construction along bluff top at, 73 ;
construction and collapse of crib wall at, 73 –74;
construction of concrete seawall at, 73 , 75 ;
enlargement and collapse of caves at, 78 , 79 ;
erosion of cliff base at, 73 ;
previously unrecognized ancient river channel at, 73 ;
solution origin of subsurface cave in sandstone at, 79 ;
subsurface cavern directly inland of the cliff at, 79 ;
tunnels in sea cliff at, 79
Soledad Mountain, 149 . See also Mount Soledad
Sorben, D., 71 ;
relation of over irrigation to groundwater indicated by, 71 , 166
Sorrento Valley, 3 , 107 ;
1884 flood and landslides in, 109 ;
history of the lower reaches of, 109 ;
1938 flood in,
109 ;
partial destruction of road by cobbles during storms of 1983 at, 108 –109;
possible structural control of, 109 ;
recent development in, 109 ;
San Diegueno Indian occupation around, 109
Sorrento Valley South through North La Jolla, high cliff of, 107 –116
Soufriere Volcano:
abundance of tornadoes in United States following eruption of, 20 ;
cold wave preceding, 20 ;
1979 eruption of, 20 ;
record rains in France and England following, 20 ;
terrible drought following eruption of, 20
Southern California:
changes in river mouths in, 144 ;
cold June in, 18 ;
flood of 1938 in, 52 ;
great flood of 1862 in, 31 ;
great flood of February 1891 in, 36 ;
storms of 1940–1941 along, 52 ;
unusual storms during winters of 1884, 1886, 1889, 1890, 1891 in, 32 –33;
weather changes along, 15 ;
windstorms along, 29
Southern hemisphere, terrible drought in, 20
Spanish Bight, 159
Stairways to beach, loss of, 82 –85
State of California:
bankruptcy in 1862 of, 31 ;
Department of Water Resources, 99
Stommel, H., 15
Submarine canyons off La Jolla:
relation to breakers along the shore by, 128 –131;
rip currents related to heads of, 130 –131
Sumner, F., 112
Sunset Cliffs, 149 ;
recent rapid erosion of, 150 –154;
slumping of cliff edge at, 150 , 154
Sunset Cliffs and Point Loma, 149 –155
Sweetwater Dam, San Diego, break in January 1916 of, 37 –38; See also Hatfield, C.
T
Tambora Volcano, cold weather conditions following, 15
Target Canyon, Camp Pendleton, 43
Tennessee, floods in, 18
Terraces:
low rock, 10 ;
termination of, 51 ;
tide pools and concretions of, 10
Tijuana, Mexico, recent erosion of beach at, 162 –163
Tijuana River, 157 ;
spit produced by, 157
Tijuana River Basins:
dams constructed along, 163 ;
effects of, 163
Torrey Pines City Beach, landslides along, 112 . See also Blacks Beach
Torrey Pines State Preserve, 111 ;
landslides along, 110 –111
Torrey Pine tree, unreliable ring in, 13
Trade winds, reversal of, 19
Tree rings, 12 –14
U
Upper part of Mississippi Valley, great flood in, 18
U.S. Army Corps of Engineers:
study by 44, 150 ;
wave study for, 55
U.S. Army Signal Corps, monthly weather review of, 10 , 15 , 36
U.S. Army Signal Service, weather records of, 16 , 24 , 70
U.S. Coast and Geodetic Survey;
charts of, 10 , 147 ;
coastal mapping by, 70 , 111 ;
description by, 51 ;
mapping in 1889 by, 34 ;
studies by, 44
U.S. Congress, 144
U.S. Department of Agriculture, weather records of, 16 , 22
U.S. Weather Bureau:
scientists of, 14 ;
weather records of, 16
V
Varves, Santa Barbara Basin, 12
Vaughan, T., 115 , 121
Ventura, California, destruction by flood in 1862 of, 31
Volcanic activity, documentation of, 11
Volcanic gases, 14
W
Wagner, A., 19 , 20
Walter Munk, 115
Wave cut terrace, 131
Weather changes preceding eruptions, 17
West Coast of South America, great floods along, 19
West Coast of United States, heavy rains along, 18 , 31 ;
windstorms along, 18
Western Geophysical Company of America, 43
Wexler, H., 14
Wide beach, formerly used as major highway for horse-drawn vehicles to Los Angeles on, 50 –51
Windansea Beach:
collapse of arch at, 139 –141;
recent sea cliff retreat near, 141 ;
seasonal sand changes at, 141
Windstorms, documentation of, 11
Woods Hole Oceanographic Institution, scientists from, 15
Woodward-Clyde Consultants, 43
Y
Yuma, Colorado, river flood twenty miles wide in late February 1891 at, 36
Z
Zuniga Jetty:
construction of, 159 ;
currents near, 163
Zuniga Jetty and the building of the Hotel Del Coronado, 159 –161
Zuniga Shoal, 157 , 163