Bollettino di Geofisica Teorica e Applicata
OGS Website
About the Journal
Contacts
To Authors
On-line Submission
Subscriptions
Forthcoming
On-line First
The Historical First Issue
Issues

2022 Vol. 63
1

2021 Vol. 62
1 / 2 / 3 / 4 / Suppl. 1 / Suppl. 2 / Suppl. 3

2020 Vol. 61
1 / 2 / 3 / 4 / Suppl. 1

2019 Vol. 60
1 / 2 / 3 / 4 / Suppl. 1 / Suppl. 2 / Suppl. 3

2018 Vol. 59
1 / 2 / 3 / 4 / Suppl. 1

2017 Vol. 58
1 / 2 / 3 / 4

2016 Vol. 57
1 / 2 / 3 / 4 / Suppl. 1

2015 Vol. 56
1 / 2 / 3 / 4

2014 Vol. 55
1 / 2 / 3 / 4

2013 Vol. 54
1 / 2 / 3 / 4 / Suppl. 1 / Suppl. 2

2012 Vol. 53
1 / 2 / 3 / 4

2011 Vol. 52
1 / 2 / 3 / 4 / Suppl. 1

2010 Vol. 51
1 / 2-3 / 4 / Suppl. 1

2009 Vol. 50
1 / 2 / 3 / 4

2008 Vol. 49
1 / 2 / 3-4 / Suppl. 1

2007 Vol. 48
1 / 2 / 3 / 4

2006 Vol. 47
1-2 / 3 / 4

2005 Vol. 46
1 / 2-3 / 4

2004 Vol. 45
1-2 / 3 / 4 / Suppl. 1 / Suppl. 2

2003 Vol. 44
1 / 2 / 3-4

2002 Vol. 43
1-2 / 3-4

2001 Vol. 42
1-2 / 3-4

2000 Vol. 41
1 / 2 / 3-4

1999 Vol. 40
1 / 2 / 3-4

1998 Vol. 39
1 / 2 / 3 / 4

1997 Vol. 38
1-2 / 3-4

1995 Vol. 37
145 / 146 / 147 / 148 / Suppl. 1

1994 Vol. 36
141-144 / Suppl. 1

1993 Vol. 35
137-138 / 139 / 140

1992 Vol. 34
133 / 134-135 / 136

1991 Vol. 33
129 / 130-131 / 132

 
 

Vol. 63, n.1, March 2022
pp. 35-50

Electrical image logs interpretation from Wenchuan earthquake Fault: Scientific Drilling project-hole4 (WFSD-4)

A.A. Konaté, H. Ma, H. Pan and N. Khan

Received: 28 March 2021; accepted: 28 June 2021; published online: 17 January 2022

Abstract

Borehole imaging is one of the most rapid and accurate methods for gathering in-situ geological feature information. The image logging data from WFSD-4 contain a mass of subsurface information, which plays a significant role in improving the understanding of the Presumed Slip Zone (PSZ) in the northern segment of the Yingxiu-Beichuan Fault. Using the electrical image logs with core data, the lithology and the PSZ characterisation were carried out. The results show abundant bedding and oblique fractures in the main lithologies. From the imaging dip interpretation, the bedding development of the 2012-2123-m section tends to be basically unchanged, but the dip angle varies frequently, and is mainly affected by the drag and pull of the fault. From 2123 m to the bottom of the well, the bedding is undeveloped, the formation is fractured seriously and the fracture breccia is obvious at 2190 m. There is a clear change in the strata: the dip angle alters from steep to gentle, and tends to change from north to south. The breakpoint position should be 2190 m, and the 2012-2190-m segment should be the hanging belt of the fault. Electrical images, conventional log as well as core analysis from WFSD-4, indicate that the slip may occur in fault breccia.



Download PDF complete


back to table of contents