Document: NRC Regulatory Guide
Document ID: cfc61809-5745-460f-8a26-13c168659924
Document Type: regulatory_guide
Title: Identification and Characterization of Seismic Sources and Determination of Safe Shutdown Earthquake Ground Motion
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740084.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.165
CFR Part: 
CFR Title: 

Content:
ua. ternary Geology and Paleoseismology," Editors H.S. Noller, LM. Sow. era, and W.R. Lettis, will be published in the spring of 1997. Copies will be available for inspection or copying for a fee from the NRC Public Document Room at 2120 L Street NW., Washington. DC; the PDR's mailing address is Mail Stop LL-6, Washington, DC 20555; telephone (202)634-3273; fax (202)53-41-3343. K 1.165-34 In the CEUS, it may not be possible to reasonably demonstrate the age of last activity of a tectonic struc ture. In such cases the NRC staff will accept association of such structures with geologic structural features or tectonic processes that are geologically old (at least pre Quaternary) as an age indicator in the absence of con flicting evidence. These investigative procedures should also be ap plied, where possible, to characterize offshore struc tures (faults or fault zones, and folds, uplift, or subsi dence related to faulting at depth) for coastal sites or those sites located adjacent to landlocked bodies of water. Investigations of offshore structures will rely heavily on seismicity, geophysics, and bathymetry rather than conventional geologic mapping methods that normally can be used effectively onshore. Howev er, it is often useful to investigate similar features on shore to learn more about the significant offshore fea tures. D.2.5 Distinction Between Tectonic and Nontectonic Deformation At a site, both nontectonic deformation and tecton ic deformation can pose a substantial hazard to nuclear power plants, but there are likely to be differences in the approaches used to resolve the issues raised by the two -" types of phenomena. Therefore, nontectonic deforma tion should be distinguished from tectonic deformation at a site. In past nuclear power plant licensing activities, surface displacements caused by phenomena other than tectonic phenomena have been confused with tectoni cally induced faulting. Such features include faults on which the last displacement was induced