ML20234D863

From kanterella
Jump to navigation Jump to search
Questions Re Bodega
ML20234D863
Person / Time
Site: 05000000, Bodega Bay
Issue date: 02/11/1964
From: Beck C
US ATOMIC ENERGY COMMISSION (AEC)
To:
Shared Package
ML20234A767 List: ... further results
References
FOIA-85-665 NUDOCS 8709220217
Download: ML20234D863 (7)
v • d • e


Text

_

^

s.

l

^N

'j Clifford K. Beck J 2/1'./64 QUESTIONS RE BODEGA

~

The basic issue to be considered is whether and to what extent there is a likelihood that differential ground motion, "f aul ti ng " ,

is likely to occur during a future earthquake in the bedrock or a

sedimentary layers which would underlay the proposed reactor facility at the Bodega Head site. The following questions are among those relevant to the basic issue:

l l A. On the bedrock at Bodena:

1. What is the age of the bedrock?
2. At what time was the bedrock first covered by sedimentary layers?
3. What significance is attached to the extensive faults on Bodega:

l >. Ub a t i s the significance of the orientation of bedrock faults?

b. What is the age of the bedrock faults?
c. Are any bedrock faults younger than others? How is this deter:nined?
4. Is the bedrock fault significantly different in any way from others in the excavation or elsewhere on Bodega? :
a. Was "the" bedrock fault occasioned by one or by many different movements? - Evidence?
b. Can the extent of (a) lateral movement; (b) vertical movement in "the" bedrock f ault be estimated?
c. Can the age of the uc st recent movement along "the" bedrock chaf t be detemined?
d. Did "the" bedrock fault move in the 1906 earthquake? How much movement may there have been, with the observational facts before us as they now are?

8709220217 851217 PDR FOIA v FIRESTOB5-665 e

PDR

5. In another 1906 type earthquake, what is the likelihood of movement of (a) 1" or less; (b) 1-2 feet; (c) > 5 feet on (1) "the" shaft fault in bedrock, (2) other bedrock faults under the proposed reactor site,(3) elsewhere on Bodega.

B. On the Sedimentary Layers at Bodega:

l

1. What is the age of the successive layers of sediment on Bodega?

How is this determined? j i

2. What is the relationship (location) between "the" bedrock shaf t fault l and the shaf t fault in the overlying sediments.
3. Assuming that the sediment fault was tectonic in origin, did it occur 1

all at one time or in several separate movements; what are the reasons l

for the opinion held?

4. What evidence e::ists for: (a) non-earthquake origin of the sediment; (b) for " smearing" of the original offset (however caused) by non-earthquake phenomena?
5. .What is age of the sediment fault? 4 100;500-5000; 40,000 - 100,000;7 millio What is evidence for this in (a) location of offset in sediment layers; (b) color banding of mineral layers; (c) other.
6. What is significance of the age of the sediment fault, to likelihood l

l sud magnitude of possible future earthquakes?

7. How much lateral movement in the bedrock within the last 100 years could be accommodated by overlying sediments without now being observable in the sediments?

C. Signi ficance of Pt. Reyes Observations:

l l

l l

l

1l

, )

A Mcd'-

2/11/64 QUESTIONS RE BODEGA ,

i The basic issue to be considered is whether and to what extent there is a likelihood of differential ground motion,  !

)

" faulting", occurring during a future earthquake in the bed-rock or sedimentary layers which would underlay the proposed reactor facility at the Bodega Head site. The following 1

questions are among those relevant to the basic issue:

A. On the bedrock at Bodega:

j

1. What is the age of the bedrock?
2. At whec time was the 6edrock first covered by sedi- l mentary layers? '

1

3. What significance is attached to the extensive faults i

on Bodega:

i

a. What is the significance of the orientation of bedrock faults?
b. What is the age of the bedrock faults?
c. Are any bedrock faults younger than others? How is this detennined?
4. Is the bedrock fault significantly different in any way from others in the excavation or elsewhere on -

Bodega?

a. What was the cause of "the" bedrock fault?

l b. Was "the" bedrock fault occasioned by one or by

_ many different movements?'- Evidence?

(

I

)

c. Can the extent of (a) lateral movement; (b) verti-cal movement in "the" bedrock fault be estimated? 1

)

d. Can the age of the most recent movement along "the" bedrock' shaft be detennined?
c. Did "the" bedrock fault move in the 1906 carth-quake? How much movement may there have been, with the observational facts before us as they now are?

]

5. In another 1906 type earthquake, what is the likelihood. ,

i of movement of (a) 1"'or less; (b) 1-2 feet; (c)) 5 feet on (1) "the" shaft fault in bedrock, (2) other bedfock l 1

faults under the proposed reactor site, (3) elsewhere on Bodega.

1 B. On the Sedhnentary Layers at Bodega:

'l. What is the age of the successive layers of sediment on Bodega? How is this determined?

2. What is the relationship (location) between "the" bed-rock shaft fault and the shaft fault in the overlying sediments.
3. Assuming that the sediment offset was tectonic in -

origin, did it occur all at one tbne or in several separate movements and what were the horizontal and vertical displacements; what are the reasons for the opinion held?

1 y

i

4. What evidence exists for: (a) tectonic origin of the i sedLment offset; (b) non-earthquake origin of the sedi-ment offset; (c) for " smearing" of the original l

offset (however caused) by non-earthquake phenomena? i 1

5. What is the age of the sedLment fault in years: A few l hundred years; a few thouscnd years; greater than l i

40 thousand years; greater than a half million years?

What is evidence for this in (a) location of offset l I

in sedLment layers; (b) color banding of mineral layers;  ;

(c) other. , j

6. What is significance of the age of the sediment fault, to likelihood and magnitude of possible future earth-quakes?.
7. How much lateral movement in the bedrock within the last 100 years could be accommodated by overlying sedi-ments without now being observable in the sediments?
8. How much displacement could occur in the bedrock at Bodega Head without rupturing the surface of the sedi-ments?

C. Significance of Pt. Reyes Observations: ,

l. How far away from (1) the 1906 trace in the San Andreas fault zone and (2) the western boundary of the zone did s

e *

.________-..--.-__a

I

)

.[f

l~

surface ruptures occur at Point Reyes as a result i

l of the 1906 earthquake?

I

2. . What was the amount of displacement (1) in the bedrock l.

and (2) in the overlying sediments of ruptures which occurred in 1906 at Point Reyes outside the main San Andreas fault zone?

3. What was the cause of these ruptures?
4. Did all of the 1906 ruptures outside the main fault line at Point Reyes apparently occur along previous fault lines and, if not, how many did?
5. What was the estbmated time of movement along these previous fault lines prior to 1906?
6. In regard to the likelihood of ruptures in the bedrock l

and ruptures in the sedbnents, what are the significant differences and similarities between Point Reyes and Bodega Head?

7. What is the probability of a rupture of the near surface i granitic rock in the Bodega excavation should a 1906 l

earthquake recur in the vicinity of Bodega Head?

1 D. Questions for Reactor Designers:

I

1. What maximum displacement of the bedrock will the reactor facility be designed to accommodate safely? l l

. 2. What is the maximum displacement'in the bedrock  !

1

- _ ____ _ a

, ]

2 e

l

(l.- . 1

<; iY ,

i that the reactor facility could be designed to accommodate safely.

i,f ,

l

3. Wat would be the . extent of 'the damage to the facility 1

l l

if.a rupture several feet of the near surface-granitic. ,

' l 'j-rock at the reactor site should occur? '

4. Wat are the estimated off-site consequences if a rupture of several feet of the near surface granitic ,

1 j

rock at the reactor site should occur?

1 i

O e

e 4 air- -,44" e r_ w . . me-me ,e a 4 - - & =

-- ._. -- _ _ - _ _ _ _ ._ _. . _ _ _ _ _ -- _ _ _ _._ . _ _ _ _ - _ _ _ - - _ _ _ _ - -

Retrieved from "https://kanterella.com/w/index.php?title=ML20234D863&oldid=3194111"