surface and subsurface events during and subsequent to the … · 2008-08-23 · surface and...
TRANSCRIPT
Surface and subsurface eventsduring and subsequent to the 1994
collapse of a portion of theAkzo salt mine, Retsof, NY
A narrative
Dr. William KellyNew York State Geological Survey
Prepared for ITGAUM 2006
Involved EntitiesNYS Geological SurveyGeological consultants
NYS Department of Environmental ConservationNYS Department of Transportation
NYS Attorney GeneralNYS Emergency Management Office
Livingston County Emergency ManagementLivingston County Economic Development Office
Livingston County Health DepartmentEffected Towns
US Geological SurveyUS Army Corps of Engineers
Mine Safety and Health AdministrationAkzo-Nobel
Rochester Gas & ElectricSUC GeneseoSUNY Buffalo
Akzo-NobelRetsof minelocation
ITGAUM Mtg2006
Generalized geologic cross-sectionRetsof mine area
Vernon “B” salt
Cuylerville
2YS
11YWRt 20A
Retsof Minefootprint ~18 mi2open area ~ 10 mi2
Geneseo
Lake Ontario
2S shear circumference
11W shear circumference
Dewatering wells
Water-filled sink holes
Rt 20A bridge
Intensity (MM) distribution map3/12/94 Cuylerville event
Modified Mercalli
IV – rattle windows, doorscreaking house frame
VI – crack plaster, masonrymove heavy furniture
Cuylerville`
Rt 20A Bridge
0
1
2
3
4
5
6
1 21 41 61 81 101 121 141 161 181 201 221 241 261 281 301 321 341 361 381 401 421 441 461 481 501 521 541 561 581 601 621 641 661 681 701 721 741 761
Se
NYSGS Seismic NetFrequency of events
(events > 1sec. with assigned magnitude)
Eventsperday
3
1
2
4
5
6
March 22, 1994 – April 21, 1996
-1.7
-1.2
-0.7
-0.2
0.3
0.8
1.3
1.8
2.3
coda
mag
nitu
de, e
vent
s>1
sec.
plot
ted
1 4 5
March 22, 1994 to April 21, 1996
Magnitude - NYSGS seismic netMc=2.2(logTc)-1.70
NYSGS Seismic netMagnitude Mc=2.2(logTc)-1.70
Felt event horizon
March 22, 1994 – April 21, 19961995 1996
Cracks in snow, March 17, 1994
Disturbed pavementRt 20A bridge, west end
Immediately after 3/12/19 event
2/14/95
Frequency of events – NYSGS seismic netAKZO salt mine
“2S”
“11W”
-1.5
-1
-0.5
0
0.5
1
1.5
coda
mag
nitu
de
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31
May, 1994
Magnitude - NYSGS seismic netMc=2.2(logTc)-1.70
-1.5
-1
-0.5
0
0.5
1
1.5
coda
mag
nitu
de
22 24 26 28 30 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 1 3
Date
Magnitude - NYSGS seismic netMc=2.2(logTc)-1.70
Seismic events May, 1994
Seismic events March 22 – April 30, 1994
2S – 15’ 11W – 4’
11W – 60’
Station CUY-2 April 8, 1994
Collapse event
Associated with the formation of sinkhole over 11W
May 25, 1994 Station CUY-3
Collapse of material over 11W associated with formation of sinkhole
Water in mine, late June ‘95
Pump out attempt 4/15Restart pumping 4/20Abandon pumping 4/24
Shoreline 9/26/94
Shoreline 10/2/95
Cross section – Genesee Valley
Shale
Shale
Carbonate
Mine
H2O-bearing zonessources of inflow to mine
Wells dry within 10 daysIndustrial well 7 mi. S lost ~160’ head
Total subsidence (ft)March 1994 –July 1995
1 mile
Total subsidence (ft)April 1995
July 1996
Sterling mine
-1-2
-3
-4
-5-6-7
Subsidence over Akzo mine 7/95
Rt 20A
Cracks
Rt 20A bridge on Little Beards Creek
Cracks from 2S sinkhole formation
Cracks
Cracks E side of 2S
Rt 20A bridge, west pier
April 5, 1994
June 15, 1994
October 8, 1994
11W
Hamilton farm
Sterling B shaft
Salt pileRetsof Fuller shaft
Rt 20A
Hamilton farm
2S
11W
Collapses 2S & 11W Sept. 94
Drill casing
Rt 20A, w of bridge
Flared gas containing ~0.03% H2S
Rt 20A bridge, Feb. ‘95
Rt 20A bridge and utilities, Apr. ‘96
2S sinkhole
Rt 20A bridge restored to approximate original grade
Rt 20A Bridge and environsNovember, 1997