The Fallacy of Interpreting SSDS with Different Types of Breccias As Seismites Amid the Multifarious Origins of Earthquakes: Implications G

Journal of Palaeogeography, 2016, ▪(▪): 1e33

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Multi-origin of soft-sediment deformation structures and seismites The fallacy of interpreting SSDS with different types of breccias as seismites amid the multifarious origins of earthquakes: Implications G. Shanmugam

Department of Earth and Environmental Sciences, The University of Texas at Arlington, Arlington, TX 76019, USA

Abstract At present, there are no criteria to distinguish soft-sediment deformation structures (SSDS) formed by earthquakes from SSDS formed by the other 20 triggering mechanisms (see a companion paper in Vol. 5, No. 4 of this journal by Shanmugam, 2016). Even if one believes that earthquakes are the true triggering mechanism of SSDS in a given case, the story is still incomplete. This is because earthquakes (seismic shocks) are induced by a variety of causes: 1) global tectonics and associated faults (i.e.,mid- ocean ridges, trenches, and transform faults); 2) meteorite-impact events; 3) volcanic eruptions; 4) post-glacial uplift; 5) tsunami impact; 6) cyclonic impact; 7) landslides (mass-transport deposits); 8) tidal activity; 9) sea-level rise; 10) erosion; and 11) fluid pumping. These different causes are important for developing SSDS. Breccias are an important group of SSDS. Although there are many types of breccias classified on the basis of their origin, five types are discussed here (fault, volcanic, meteorite impact, sedimentary-depositional, sedimentary-collapse). Although different breccia types may resemble each other, distinguishing one type (e.g., meteorite breccias) from the other types (e.g., fault, volcanic, and sedimentary breccias) has important implications. 1) Meteorite breccias are characterized by shock features (e.g., planar deformation features in mineral grains, planar fractures, high-pressure polymorphs, shock melts, etc.), whereas sedimentary- depositional breccias (e.g., debrites) do not. 2) Meteorite breccias imply a confined sediment distribution in the vicinity of craters, whereas sedimentary-depositional breccias imply an unconfined sediment distribution, variable sediment transport, and variable sediment provenance. 3) Meteorite, volcanic, and fault breccias are invariably subjected to diagenesis and hydrothermal mineralization with altered reservoir quality, whereas sedimentary-depositional breccias exhibit primary (unaltered) reservoir quality. And finally, 4) sedimentary-collapse breccias are associated with economic mineralization (e.g., uranium ore), whereas sedimentary-depositional breccias are associated with petroleum reservoirs. Based on this important group of SSDS with breccias, the current practice of interpreting all SSDS as “seismites” is inappropriate. Ending this practice is necessary for enhancing conceptual clarity and for advancing this research domain.

E-mail address: [email protected]. Peer review under responsibility of China University of Petroleum (Beijing). http://dx.doi.org/10.1016/j.jop.2016.09.001 2095-3836/© 2017 China University of Petroleum (Beijing). Production and hosting by Elsevier B.V. on behalf of China University of Petroleum (Beijing). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Keywords Breccias, Earthquakes, Faults, Global tectonics, Meteorite impacts, Seismites, Soft-sediment deformation structures (SSDS)

© 2017 China University of Petroleum (Beijing). Production and hosting by Elsevier B.V. on behalf of China University of Petroleum (Beijing). This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/). Received 29 July 2016; accepted 7 September 2016; available online xxx

3) Volcanic eruptions (Moran et al., 2008). 1. Introduction 4) Post-glacial uplift (Fjeldskaar et al., 2000). 5) Tsunami impact (Tappin et al., 2001). This article is a companion to my earlier paper 6) Cyclonic impact (Meng et al., 2013). “The seismite problem” (Shanmugam, 2016). The 7) Landslides (Mass-transport deposits) (Pankow purpose of the original paper was to explain that there et al., 2014). are no objective criteria to recognize earthquakes as a 8) Tidal activity (Barruol et al., 2013). unique triggering mechanism (among 20 others) of 9) Sea-level rise (Brothers et al., 2013). soft-sediment deformation structures (SSDS) (Fig. 1). 10) Erosion (Steer et al., 2014). Even if one recognizes earthquakes as the mechanism 11) Fluid pumping (Zhang et al., 2013). that contributed to the origin of SSDS, the geological story is still incomplete. This is because earthquakes Given these alternatives, simply naming a deposit are generated by a multitude of causes. Selected ex- as “seismites” without identifying the root cause of amples are: seismic shock responsible for the deformation is incomplete in understanding the geological origin of 1) Global tectonics (Kearey et al., 2009; Ruff, 1996). SSDS. An analogy in the ﬁeld of clinical diagnosis 2) Meteorite-impact events (Collins et al., 2005). would be like a doctor of medicine diagnosing a

Fig. 1 Selected types of triggers, state of liquefaction, and soft-sediment deformation structures (SSDS). There are 21 triggers and they are all directly or indirectly responsible for sediment transport, deposition, and liquefaction. In reﬂecting published literature, earthquakes and tectonic activity are listed as two different types. However, earthquakes and volcanism are an integral component of global tectonics (Kearey et al., 2009). Note that both tectonic and non-tectonic triggers go through liquefaction in developing SSDS. Also note that earthquake is one of many triggers that can develop SSDS. SSDS are not seismites. Thin blue arrows: One or more sediment transport processes with or without ﬂow transformations (Fisher, 1983). Thick gray arrow: Final deposition. See Shanmugam (2006a, 2006b, 2008a, 2008b, 2012a, 2013b, 2015, 2016) for discussion of examples of triggers shown here (Basilone et al., 2014, Beck, 2009, Boulton et al.,2001, Gradmann et al., 2012, Malkawi and Alawneh, 2000, Obermeier et al., 2002, Scholz et al., 2011, Shanmugam, 2012b, Shanmugam, 2013a, Shanmugam et al., 1988, Simms, 2003). Figure from Shanmugam (2016).

Fig. 2 A − Elastic rebound mechanism showing earthquake (fault) generation (elastic rebound theory). (a) A block of rock traversed by a pre- existing fracture (or fault) is being strained in such a way as eventually to cause relative motion along the plane of the fault. AB horizontal line = Marker indicating the state of strain of the system. Broken vertical line = Location of the fault. (b) Relatively small amounts of strain can be accommodated by the rock. (c) When the strain reaches the level at which it exceeds the frictional and cementing forces opposing movement along the fault plane. (d) Finally, fault movement occurs instantaneously. Figure from Kearey et al. (2009);B− Distribution of compressional and dilational P wave ﬁrst motions about an earthquake. Figure from Kearey et al. (2009);C− Three types of basic faults along which earthquakes are generated. Credit: USGS; colored version from Wikipedia.

Fig. 3 A digital tectonic activity map of the Earth showing tectonism and volcanism during the past one million years. Note the distribution of different types of faults (see Legend on the lower right corner of the map). Also note that earthquakes and volcanism are an integral component of global tectonics. Credit: NASA Goddard Space Flight Center, Greenbelt, Maryland 20771. Figure from Lowman et al. (1999).

Fig. 4 Map showing locations of epicenters (358,214 events during 1963e1998) along plate boundaries. Credit: NASA, DTAM project team (http://denali.gsfc.nasa.gov/dtam/seismic/).

Fig. 5 Cross-section of a subduction zone (trench) showing locations of seismicity (shaded areas). All plotted seismicity locations have had at least one large earthquake (M > 7.5). Figure from Ruff (1996).

According to Goslin et al. (2005), the seismicity of the Magnitude: 7.8 Mw (ASCE, 1907). northern Mid-Atlantic Ridge was recorded by two hy- 3) 1989 Loma Prieta earthquake: October 17, 1989. drophone networks moored in the sound fixing and Magnitude: 6.9 Mw (Stover and Coffman, 1993). ranging (SOFAR) channel, on the flanks of the Mid- Atlantic Ridge, north and south of the Azores. During In addition, earthquakes are known to occur away a period of operation (05/2002e09/2003), the north- from plate boundaries, such as in Central Australia ern ‘SIRENA’ network, deployed between latitudes (Fig. 7). Consequently, earthquakes are omnipresent. 40200N and 50300N, recorded acoustic signals generated by 809 earthquakes on the hotspot-influenced 3.2. Meteorite-impact events Reykjanes Ridge. Tryggvason (1973) documented that the seismicity of the Iceland region is concentrated The role of meteorite impact on sedimentation is a along the crest of the Mid-Atlantic Ridge and in two taboo topic, particularly in petroleum exploration shear zones connecting the two ends of the eastern (Shanmugam, 2012a). But meteorite impacts have volcanic zone in Iceland to the ridge crest on both sides been well documented worldwide (Fig. 8). The top ten of Iceland (Fig. 6). meteorite-impact structures in the world are listed in Ruff (1996, p. 91) states that “Subduction zones Table 1. In North America, meteorite impacts of generate most of the world's seismicity, and all of the various ages have been documented (Fig. 9). The ki- largest earthquakes”. A cross-section of a subduction netic energy calculated for impactors varying from 4 m zone illustrates the close link between seismicity and to 1000 m in diameter is given in Table 2. The 1908 subduction (Fig. 5). Perhaps, the best known transform “Tunguska event” in Siberia is considered to be the fault is the San Andreas Fault, which extends roughly largest impact event on Earth in recorded history. Early 1300 km through California (USA) and even northern estimates of the energy of the air burst range from 10 Mexico. It forms the tectonic boundary between the to 15 megatons of TNT (Shoemaker, 1983). Schulte Pacific Plate and the North American Plate, and its et al. (2010) reviewed the geological significance of motion is right-lateral strike-slip. Examples of three the third largest Chicxulub asteroid impact at the K−Pg earthquakes associated with this fault system are: boundary on the northern Yucatan, Mexico (Fig. 9). This K−Pg event generated major mass movements not 1) 1857 Fort Tejon earthquake: January 9, 1857. only directly by the impact-induced seismic shock

Magnitude: 7.9 Mw (Stover and Coffman, 1993). (Bralower et al., 1998; Busby et al., 2002; Day and

Fig. 6 A − Distribution of volcanoes along the Mid-Atlantic Ridge in the Iceland region. Credit: USGS; B − Distribution of earthquakes along the Mid-Atlantic Ridge in the Iceland region. Figure from Tryggvason (1973). Note that earthquakes and volcanism are an integral component of global tectonics.

Fig. 7 World seismicity map. Earthquakes represented are (1) M5.51, 1900e2002, (2) M3.51, 1990e2008, US lower 48 and Hawaii, and (3) M4.51, 1990e2009, Alaska. Credit: USGS (http://earthquake.usgs.gov/earthquakes/world/seismicity/). Accessed November 18, 2010. Figure from Shanmugam (2012a), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943960750294. License Date: September 7, 2016.

Maslin, 2005; Norris and Firth, 2002), but also by the eruption and the subsequent 2004 eruption have been impact-triggered tsunamis (Claeys et al., 2002; well documented by the U.S. Geological Survey (Moran Shanmugam, 2012a; Smit et al., 1996). The kinetic et al., 2008; Tilling et al., 1990). energy derived by the impact is estimated at Seismicity data, for example, were collected ~5 × 1030 erg, which is equivalent to 108 Mt of TNT or a from numerous stations located in the Mount St. Richter-magnitude 13 earthquake (Covey et al., 1994). Helens seismic network when swarm began on Therefore, seismic shocks associated with impacts are September 23, 2004 (Fig. 11). Empirical data show indeed formidable. Indeed, the great magnitude of that nearly every volcanic eruption is preceded by an extraterrestrial collisions were capable of causing increase in seismicity (i.e., by an earthquake swarm) widespread extinctions worldwide (Becker, 2002). (Waite et al., 2008). The origins of volcanic earthquake swarms are discussed by Roman and Cashman 3.3. Volcanic activity (2006). Iceland is a region of not only volcanoes but also earthquake swarms along the Mid-Atlantic Ridge Volcanic earthquakes are the direct result of the (Fig. 6). movement of magma (Lahr et al., 1994). Volcanoes are a major cause of earthquakes along modern (Fig. 10) 3.4. Glacial activity and ancient continental margins. The Smithsonian Institution map reveals the importance of volcanoes Fjeldskaar et al. (2000) discussed the importance worldwide along plate boundaries and some conti- of postglacial uplift, neotectonics, and related seis- nental margins (Fig. 10). The 1980 Mount St. Helens micity in Fennoscandia (Fig. 12).

Fig. 8 Frequency of small asteroids roughly 1e20 m in diameter impacting Earth's atmosphere. Credit: NASA, Jet Propulsion Laboratory, California Institute of Technology (http://www.jpl.nasa.gov/news/news.php?release=2014-397). Accessed July 19, 2016.

Table 1 Top ten impact structures in the world that include the Chicxulub (see Fig. 9) in Yucatan, Mexico. Data from PASSC (Planetary and Space Science Centre), University of New Brunswick, Fredericton, New Brunswick, Canada (http://www.passc.net/EarthImpactDatabase/ NorthAmerica.html). Accessed April 5, 2011. Rank Diameter Crater name Location Latitude Longitude Age (Ma) km (mi) 1 300 (186) Vredefort South Africa S 27000 E27300 2023 ± 4 2 250 (155) Sudbury Ontario, Canada N 46360 W81110 1850 ± 3 3 170 (106) Chicxulub (Fig. 9) Yucatan, Mexico N 21200 W89300 64.98 ± 0.05 4 100 (62) Popigai Russia N 71390 E 111110 35.7 ± 0.2 5 100 (62) Manicouagan Quebec, Canada N 51230 W68420 214 ± 1 6 90 (56) Chesapeake Bay Virginia, U.S.A. N 37170 W76010 35.5 ± 0.3 7 90 (56) Acraman South Australia S 32010 E 135270 ~590 8 80 (50) Puchezh-Katunki Russia N 56580 E43430 167 ± 3 9 70 (43) Morokweng South Africa S 26280 E23320 145.0 ± 0.8 10 65 (40) Kara Russia N 69060 E64090 70.3 ± 2.2

km = kilometer, mi = mile; 1 km = 0.621 mi.

West et al. (2010) presented evidence for glacial 3.5. Tsunami impact seismicity in Alaska (Fig. 13). They presented a framework for interpreting small glacier seismic Tsunamis are oceanographic phenomena that events based on data collected near the center of represent a water wave or series of waves, with long Bering Glacier, Alaska, in the spring 2007. They wavelengths and long periods, caused by an impulsive found that extremely high microseismicity rates (as vertical displacement of the body of water by earth- many as tens of events per minute) occurred largely quakes, landslides, volcanic explosions or extrater- within a few kilometers of the receivers. A high- restrial (meteorite) impacts. Earthquakes commonly frequency class of seismicity was distinguished by generate tsunamis through the transfer of the large- dominant frequencies of 20e35 Hz and by impulsive scale elastic deformation associated with ruptures to arrivals.

Fig. 9 Map showing sites of meteorite impacts in North America, including the Chicxulub (K−Pg) in the Yucatan Peninsula. Credit: PASSC (Planetary and Space Science Centre), University of New Brunswick, Fredericton, New Brunswick, Canada (http://www.passc.net/ EarthImpactDatabase/NorthAmerica.html). Accessed April 5, 2011. Figure from Shanmugam (2012a), with permission from Elsevier. Copy- right Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943960750294. License Date: September 7, 2016. potential energy within the water column (Geist, hit the north coast of Papua New Guinea. Tappin et al. 2005). Aspects of tsunamis are discussed by (2001) attributed this tsunami to submarine slumps. Shanmugam (2008b). Tsunamis generated submarine slumps, which in turn On July 17, 1998, a magnitude 7.0 earthquake triggered tsunamis. The importance here is that large- generated a series of catastrophic tsunami waves that scale mass movements are closely associated with

Table 2 d Properties of impact events with varying diameters of impactors (stony asteroids). From Marcus et al. (2010). See also Collins et al. (2005). All based on density of 2600 kg/m3, speed of 17 km/s, and an impact angle of 45. URL: https://en.wikipedia.org/wiki/ Impact_event. Accessed July 25, 2016. Impactor Kinetic energy at atmospheric entry Kinetic energy at airburst Airburst altitude Average frequency (years) diameter 4 m (13 ft) 3 kt 0.75 kt 42.5 km (139,000 ft) 1.3 7 m (23 ft) 16 kt 5 kt 36.3 km (119,000 ft) 4.6 10 m (33 ft) 47 kt 19 kt 31.9 km (105,000 ft) 10 15 m (49 ft) 159 kt 82 kt 26.4 km (87,000 ft) 27 20 m (66 ft) 376 kt 230 kt 22.4 km (73,000 ft) 60 30 m (98 ft) 1.3 Mt 930 kt 16.5 km (54,000 ft) 185 50 m (160 ft) 5.9 Mt 5.2 Mt 8.7 km (29,000 ft) 764 70 m (230 ft) 16 Mt 15.2 Mt 3.6 km (12,000 ft) 1900 85 m (279 ft) 29 Mt 28 Mt 0.58 km (1900 ft) 3300 100 m (330 ft) 47 Mt 3.8 Mt 1.2 km (0.75 mi) 5200 130 m (430 ft) 103 Mt 31.4 Mt 2 km (1.2 mi) 11,000 150 m (490 ft) 159 Mt 71.5 Mt 2.4 km (1.5 mi) 16,000 200 m (660 ft) 376 Mt 261 Mt 3 km (1.9 mi) 36,000 250 m (820 ft) 734 Mt 598 Mt 3.8 km (2.4 mi) 59,000 300 m (980 ft) 1270 Mt 1110 Mt 4.6 km (2.9 mi) 73,000 400 m (1300 ft) 3010 Mt 2800 Mt 6 km (3.7 mi) 100,000 700 m (2300 ft) 16,100 Mt 15,700 Mt 10 km (6.2 mi) 190,000 1000 m (3300 ft) 47,000 Mt 46,300 Mt 13.6 km (8.5 mi) 440,000

km = kilometer, m = meter, mi = mile, ft = foot; 1 km = 0.621 mi; 1 ft = 0.3048 m.

Fig. 10 Map showing volcanoes of the world. Large red triangles show volcanoes with known or inferred Holocene eruptions; small red triangles mark volcanoes with possible, but uncertain Holocene eruptions or Pleistocene volcanoes with major thermal activity. Data on Global Volcanism: 1968e2002 (Venzke et al., 2002). Credit: Smithsonian Institution, Global Volcanism Program (http://www.volcano.si.edu/ world/ﬁnd_regions.cfm). Accessed November 18, 2010. Figure from Shanmugam (2012a), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943960750294. License Date: September 7, 2016.

Fig. 11 A − Photograph showing Mount St. Helens lava dome. Originally published as the cover photo of the U.S. Geological Survey Pro- fessional Paper 1750 (Moran et al., 2008); B − Location of stations in Mount St. Helens seismic network. Black triangles correspond to Paciﬁc Northwest Seismic Network (PNSN) stations in place when swarm began on September 23, 2004; and red triangles correspond to stations installed after eruption began. Inset map shows crater stations superimposed on digital elevation model from April 19, 2005. Most crater stations were added after start of 2004 eruption. Many newly added stations operated for short periods; at most, six crater stations were operational at any one time.

seismicity (Pankow et al., 2014; Parsons et al., 2014; in seismicity: The atmosphere pressure drop unloaded Tappin et al., 2014). As noted earlier, the Chicxulub the surface, which brought the reverse faults closer to asteroid impact at the K−Pg boundary on northern failure. Yucatan, Mexico (Fig. 9) had generated not only major mass movements directly by the impact-induced 3.7. Landslides (mass-transport deposits) seismic shock (Bralower et al., 1998; Busby et al., 2002; Day and Maslin, 2005; Norris and Firth, 2002), Landslides represent mass-transport deposits but also by the impact-triggered tsunamis (Claeys (MTD) (Shanmugam, 2015). Although it is well docu- et al., 2002; Smit et al., 1996). mented that earthquakes invariably cause faulting and related MTD, MTD can also trigger earthquakes. One of 3.6. Cyclonic impact the best documented case studies is by Pankow et al. (2014) in Utah (Fig. 14). Pankow et al. (2014) sum- Tropical cyclones are meteorological phenomena. marized the results as follows: Structurally, tropical cyclones are large, rotating systems of clouds, winds, and thunderstorms. In the “On the evening of 10 April 2013, a massive land- Northern Hemisphere the rotation is counterclock- slide occurred at the Bingham Canyon copper mine wise, but in the Southern Hemisphere the rotation is near Salt Lake City, Utah, USA. The northeastern clockwise due to the Coriolis force. The destructive wall of the 970-m-deep pit collapsed in two distinct power of cyclones was discussed by Shanmugam episodes that were each sudden, lasting ~90 s, but (2008b). Meng et al. (2013) reported that a statisti- separated in time by ~1.5 h. In total, ~65 million cally signiﬁcant increase of seismicity rate was found cubic meters of material was deposited, making the when Hurricane Irene (August 2011) passed by the cumulative event likely the largest non-volcanic epicentral region, located in Louisa County, Virginia, landslide to have occurred in North America in where an Mw 5.8 earthquake struck in 2011. Meng et al. modern times. Fortunately, there were no fatalities (2013) offered a possible explanation for the increase or injuries. Because of extensive geotechnical

Fig. 12 Earthquakes in Fennoscandia during different periods of observation. Figure from Fjeldskaar et al. (2000), with permission from Pergamon Press (Elsevier). Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943820304821. License Date: September 7, 2016.

surveillance, mine operators were aware of the that is visible throughout the network (6e400 km).

instability and had previously evacuated the area. Local magnitudes (ML) for the two slides, which are The Bingham Canyon mine is located within a dense based on the amplitudes of short-period waves, regional network of seismometers and infrasound were estimated at 2.5 and 2.4, while magnitudes

sensors, making the 10 April landslide one of the based on the duration of seismic energy (Md) were best recorded in history. Seismograms show a much larger (>3.5). This magnitude discrepancy, complex mixture of short- and long-period energy and in particular the relative enhancement of long-

Fig. 13 Left: Map of lower Bering Glacier experiment overlain on Landsat imagery. Triangles mark locations of seismic stations. Right: Seismic event classes from Bering Glacier and Augustine Volcano. A − Sample waveforms from Bering Glacier. Dominant frequencies are shown along left side; B − Sample waveforms from Augustine Volcano; C − Distribution of dominant frequencies at Bering Glacier; D − Distribution of dominant frequencies at Augustine Volcano. Figure from West et al. (2010).

period energy, is characteristic of landslide seismic summarized that “Turnagain Arm is a semidiurnal sources. Interestingly, in the six days following the hypertidal estuary in southeastern Alaska with a landslide, 16 additional seismic events were recorded tidal range of 9 m. Contorted bedding and detected and located in the mine area. Seismo- ﬂow rolls preserved in tidal sediments within the grams for these events have impulsive arrival estuary have previously been interpreted as resulting

characteristics of tectonic earthquakes. Hence, it from the Mw 9.2 Great Alaskan Earthquake of 1964. appears that in this case the common geological Horizons of flow rolls between undeformed beds in sequence of events was inverted: Instead of a large sediments and rock strata have been used to infer earthquake triggering landslides, it was a landslide ancient earthquakes in other areas. Although many that triggered several small earthquakes”. Details types of soft-sediment deformation structures can be are illustrated in Fig. 14. formed by earthquakes, observations of sedimentation on tidal flats in the inner parts of Turnagain Arm in the summers of 2003 and 2004 show that a wide 3.8. Tidal activity range of soft-sediment deformation structures, similartothoseinferredtohavebeenformedby Barruol et al. (2013) through deployment of a earthquakes, can form in macrotidal estuaries in the seismic network along the Adelie and George V coasts absence of seismic shock. During sedimentation rate in East Antarctica during the period 2009e2012 pro- measurements in 2004, soft sediment deformation vided the opportunity to monitor cryoseismic activity structures were recorded that formed during one and to obtain new insights on the relationship between day's tide, either in response to overpressurization of tidal cycles and coastal glacier dynamics. They re- tidal flats during rapid tidal drawdown or by shear ported numerous icequakes (50,000 events within 10 stress exerted on the bed by the passage of a 1.8 m months; and can be up to 100 events/hour) and a clear tidal bore. Structures consisted of flow rolls, dish tidal modulation. Barruol et al. (2013) suggested that structures, flames, and small dewatering pipes in a they result from ice friction and fracturing around the bed 17 cm thick. In the future, if the flow rolls in rocky peak and from the glacier flexure in response to Turnagain Arm were found in isolated outcrops across the falling and rising tides at its grounding area. an area 11 km in length, in an estuary known to have Tidal forces themselves are powerful enough to been influenced by large-magnitude earthquakes, cause SSDS. For example, in a convincing case study would they be interpreted as seismites? These ex- advocating an alternative tidal origin to seismic amples show that caution is needed when using ho- origin of SSDS, Greb and Archer (2007, p. 435) rizons of flow rolls to infer paleoseismicity in

Fig. 14 Landslide-triggered earthquakes in Utah on April 11, 2013. A − Index map of the United States showing the state of Utah; Credit: Wikipedia; B − University of Utah seismic and infrasound network, and location of the Bingham Canyon mine; C − Photograph of the 11 April 2013 rock avalanche (copyright Kennecott Utah Copper, used with permission). Elevation of the crest and toe of the slide are shown, as well as an estimate of the runout distance along the arcuate travel path. A group of large haul trucks damaged by the slide can be seen at lower left; D − Seismic and acoustic waveforms recorded at NOQ (13 km from slide), the closest broadband seismic station. Seismic traces are vertical component-velocity in different frequency bands (broadband, high-passed at 1 Hz, low-passed at 0.1 Hz); acoustic traces are infrasonic beams steered toward the mine in a pass band of 0.5e5.0 Hz. Gray-shaded boxes indicate time period with coherent signal originating from the mine. Amplitude scales are consistent for each pass band (i.e., they are consistent across each row). B, C, and D from Pankow et al. (2014). Credit for B, C, and D: GSA. estuarine deposits because many of the mechanisms 3.9. Sea-level rise (tidal flux, tidal bores, slumping, flooding) that can cause deformation in rapidly deposited, unconsoli- Brothers et al. (2013, p. 979) investigated the dated silts and sands, are orders of magnitude more causal relationships between rapid sea-level rise, common than great earthquakes”. Other studies also flexural stress loading, and increased seismicity rates attributed the origin of SSDS to tidal processes along passive margins (Fig. 15). They found that (Tessier and Terwindt, 1994). Coulomb failure stress across fault systems of passive

Fig. 15 Conceptual models for flexural loading of continental margin following rapid eustatic sea-level rise. A − Margin configuration prior to sea-level rise; B − Configuration following rapid sea-level rise. Added loading of water on shelf induces flexural bending stresses on underlying elastic plate (red arrows represent compression; blue arrows represent tension). Figure from Brothers et al. (2013). continental margins may have increased more than 1 MPa during rapid late Pleistoceneeearly Holocene sea-level rise, an amount sufficient to trigger fault reactivation and rupture. These results suggest that sea-levelemodulated seismicity may have contributed to a number of poorly understood but widely observed phenomena. These phenomena include 1) increased frequency of large-scale submarine landslides during rapid, late Pleistocene sea-level rise; 2) emplacement of coarse-grained mass-transport deposits on deep-sea fans during the early stages of marine transgression; and 3) the unroofing and release of methane gas sequestered in continental slope sediments.

3.10. Erosion

Conventionally, deep tectonic processes over a seismic cycle are considered as the only persistent Fig. 16 Mechanism of Coulomb stress loading of a thrust fault by mechanism driving the stress loading of active faults. surface erosion. Distribution of stress increment Ds (here purely However, Steer et al. (2014) showed via a mechanical illustrative) induced by a punctual erosion at the surface, increasing Dt Ds model (Fig. 16) that at the timescale of a seismic both the tangential (driving effect) and the normal stresses n (unclamping effect). Figure from Steer et al. (2014). cycle, erosion also significantly influences the stress loading of thrust faults. The authors have shown that erosion rates of about ~0.1e20 mm/year, as docu- injection of fluid either into a basal sedimentary mented in Taiwan, China, can raise the Coulomb stress reservoir with no underlying confining unit or directly by ~0.1e10 bar on nearby thrust faults over the inter- into the underlying crystalline basement complex. The seismic phase. Such stresses are probably sufficient to authors speculated that the earthquakes probably trigger shallow seismicity or promote rupture of deep occurred along faults that were likely critically continental earthquakes up to the surface. stressed within the crystalline basement. These faults were located at a considerable distance (up to 10 km) 3.11. Fluid pumping from the injection wells. Another example is the Three Gorges Project in Zhang et al. (2013) presented a case study in which China where earthquakes are generated by the reser- earthquakes were induced by fluid pumping. In this voir (Yao et al., 2013). Although human-induced study, a series of Mb 3.8e5.5 induced seismic events in earthquakes are included here for completeness, they the midcontinent region, United States, resulted from are irrelevant for interpreting ancient rock record.

Helwig, 1970; Kirkland and Anderson, 1970; Logan, 4. Origins of breccias and their 1863; Maltman, 1984, 1994). Obermeier et al. implications (2005) discussed the importance of liquefaction- induced SSDS created by earthquakes. Such SSDS 4.1. Types of breccias include angular clasts or breccias (Fig. 17). Although seismic shear waves are considered to be the com- Breccias are broken angular fragments of minerals mon cause of liquefaction and related deformation and rocks that comprise an important kind of SSDS. There (Greene et al., 1994), Holzer and Youd (2007) re- are many types of breccias based on their genesis, which ported that excess pore-water pressure and lique- include 1) frictional wear in fault zones (Sibson, 1986), 2) faction at the Wildlife Liquefaction Array (California) sediment transport and deposition (Shanmugam, 2012a), in 1987 were caused by deformation associated with 3) sediment loading (Shanmugam, 2016), 4) sediment both high-frequency strong ground motion and 5.5-s- collapse due to dissolution (Friedman, 1997), 5) volca- period Love waves. However, not all breccias are nic/pyroclastic activity (Fisher, 1984), 6) meteorite formed by earthquakes (e.g., sedimentary breccia impact (Bischoff et al.,2006), and 7) hydrothermal ac- deposited by debris flows; breccias caused by tivity (Jebrak, 1997). In this review, five important types solution-collapse, etc.). Importantly, not all earth- (fault, volcanic, meteorite impact, sedimentary- quakes are formed by a single cause (e.g., tectonic depositional, and sedimentary-collapse) are considered. versus meteorite-impact events). The following dis- The origin of SSDS has been a challenge ever since cussion and case studies illustrate the challenges and they were recognized (Allen, 1984; Collinson, 1994; implications associated with interpreting five types

Fig. 17 Schematic section showing the occurrence of seismic-liquefaction induced SSDS. This scenario is applicable to both subaerial and submarine environments that are subjected to seismic shaking. Note angular mud clasts or breccias in sand injections. Originally from Obermeier et al. (2005). Figure from Shanmugam (2012a), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943960297024. License Date: September 7, 2016.

Fig. 18 A − Geological map of the Pembrokeshire Peninsula, southwest Wales, United Kingdom, with 30 breccia localities associated with faults; B − Location and geological context of main map. Figure from Woodcock et al. (2014), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943690558071. License Date: September 7, 2016.

Fig. 19 A − Outcrop photograph showing breccia zones related to vertical cross faults at Flimston Bay (locality 1, Fig. 18). Photo by Sid Howells; B − An example of chaotic breccia at Bullslaughter east (locality 3, Fig. 18); C − An example of crackle breccia at Proud Giltar (locality 17, Fig. 18). All three ﬁgures are from Woodcock et al. (2014), with permission from Elsevier. Copyright Clearance Center's Right- sLink: Licensee: G. Shanmugam. License Number: 3943690558071. License Date: September 7, 2016.

4) Smearing of clays and creation of fault seals (Caine interpreted as the dilational tips of listric normal et al., 1996; Egholm et al., 2008). faults, and the cross-strike faults as transtensional 5) Fault sealing and fluid flow in hydrocarbon reser- transfer zones. Sub-horizontal clast fabrics suggest voirs (Knipe et al., 1998). brecciation by gravitational collapse into opening 6) Cementation and reduction of porosity (Minor and fissures rather than by cataclasis along the faults. The Hudson, 2006). importance of this case study is that various authors have offered different mechanisms to explain the In a detailed field study of chaotic breccia zones origin of breccias in South Wales (Fig. 20B): on the Pembroke Peninsula of South Wales (Fig. 18), Woodcock et al. (2014) documented evidence for 1) Dixon (1921) proposed karstic solution of limestone, collapse into voids along dilational faults. They have producing large voids into which wall and roof rocks mapped faults and classified breccia types using 30 progressively collapsed (Fig. 20Ba). localities (Fig. 18). Chaotic breccias and mega- 2) Hancock (1964) and Thomas (1970) proposed for- breccias (Fig. 19A) hosted within the Pembroke mation by tectonic fragmentation along faults Limestone Group (Visean, Mississippian, Lower (Fig. 20Bb). Carboniferous) of southwest Wales are re-mapped 3) Woodcock et al. (2006) attributed megabreccia along with spatially-related crackle and mosaic along the Dent Fault, Northwest England, to breccias (Fig. 19B). Of thirteen studied megabreccia collapse of voids produced by dilational fault bodies, seven lie along steep, NNW- or NNE-striking displacement (Fig. 20Bc). strike-slip faults originating during North−South 4) Walsh et al. (2008) concluded that the mega- Variscan (Late Carboniferous) shortening (Fig. 20A), breccias were formed by more than one mecha- though reactivated during later extension. Four nism, and suggested a phreatic explosion due to bodies are conformable with EeW striking, steeply- upward escape of thermally-driven superheated dipping bedding, and two have irregular or indeter- fluids (Fig. 20Bd). This type could also be classified minate margins. The bedding parallel zones are as volcanic breccias.

Fig. 20 A − (a) Diagrammatic map of folds and conjugate strike−slip faults formed by north−south Variscan shortening; (b) Map of postulated post-Variscan north−south extensional reactivation of Variscan faults and steepened bedding; (c) Cross-section across a dilational normal fault that steepens to parallel bedding at shallow depths; B − Schematic diagram of four types of breccia formation mechanisms (see text for details). Breccia types are labeled in this article. Both ﬁgures are from Woodcock et al. (2014), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943690558071. License Date: September 7, 2016.

4.3. Volcanic breccias composed of broken, angular, pyroclastic fragments, is common in both subaerial (Fig. 21)(Fisher, 1984) and Volcanic breccias represent not only those that submarine (Head and Wilson, 2003) environments. occur within the central vent but also that accumulate fl fl from pyroclastic debris ows or lahar on the anks of a 4.4. Meteorite breccias volcano. Fisher (1960) classified volcanic breccias into three major categories based on process of Meteorite breccias (also known as impact breccias) fragmentation: are diagnostic of an impact event such as an asteroid or comet striking the Earth. Breccias of this type may be 1) Autoclastic breccias. present on or beneath the floor of the crater, on the rim, 2) Pyroclastic breccias (Fig. 21). or in the ejecta expelled beyond the crater. Bischoff 3) Epiclastic breccias. et al. (2006) discussed the nature and origins of meteorite breccias. They have described nine types, namely: Autoclastic volcanic breccias result from internal processes acting during movement of semisolid or solid lava; they include flow breccia and intrusion breccia. 1) Primitive, accretionary. Pyroclastic breccias are produced by volcanic explo- 2) Genomict breccias. sion and include vulcanian breccia, pyroclastic flow 3) Regolith breccias. breccia, and hydrovolcanic breccia. Epiclastic volcanic 4) Fragmental breccias. breccias result from transportation of loose volcanic 5) Impact melt breccias (Fig. 22). material by epigene geomorphic agents, or by gravity, 6) Granulitic breccias. and include laharic breccia, water-laid volcanic 7) Polymict breccias. breccia, and volcanic talus breccia. Other volcanic 8) Monomict breccias. breccia terms are discussed. The pyroclastic type, 9) Dimict breccias.

Fig. 21 A − Photograph of Mount St. Helens. Plumes of steam, gas, and ash often occurred at in the early 1980s. Photo by Lyn Topinka. Credit: Wikipedia; B − Angular pumice blocks near the front of a volcanic debris flow associated with the eruption of the Mount St. Helens on May 18, 1980. This type of deposits is qualified to be classified both as “volcanic breccia” and as “sedimentary−depositional breccia”. Photo by T.A. Leighley. Credit: USGS (http://libraryphoto.cr.usgs.gov/cgi-bin/show_picture.cgi?ID=ID.CVO-F.73ct&SIZE=large), October 17, 1980. Accessed February 27, 2011. Figure from Shanmugam (2012a), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3950801388442. License Date: September 16, 2016.

Cantarell Oil Field, Mexico: In a rare case study, Grajales−Nishimura et al. (2000) attributed the origin of oil-producing (1.3 million barrels per day) carbonate-breccia reservoir facies in the Cantarell Oil Field in Mexico to major slumping, caused by the Chicxulub impact (K−Pg Boundary) and related tsunamis. The lower oil-producing breccia unit is nearly 300 m (984 ft) in thickness (Grajales−Nishimura et al., 2000, their Fig. 2A). It exhibits secondary vuggy porosity due to dissolution. Its average porosity varies from 8% to 12% and its permeability is commonly in the range of 3000−5000 mD. This is the only reported Fig. 22 An example of meteorite breccia. Typical texture of an petroleum-producing reservoir associated with the impact melt clast within an R chondrite. From Bischoff et al. (2006). Chicxulub event. See also Bischoff (2000). Credit: University of Arizona Press. Alamo Event, Devonian, Nevada: The Alamo Event produced diagnostic megabreccias (Fig. 25). Pinto and Warme (2008) established a crater stratigraphy with Characteristics of meteorite breccias are discussed ﬁve breccia units that characterize the Rim Realm, in using case studies below. Although limited in number, ascending order: 1) deformed target rocks, 2) injected the following case studies are useful for understanding dikes and sills, 3) chaotic fallback, 4) smeared fall- meteorite breccias. back, and 5) resurge. Chicxulub Impact Crater, Yucatan, Mexico (Fig. 23): Kardla€ Crater, NW Estonia: Kleesment et al. (2006) An ideal impact breccia sequence with six divisions discussed impact-induced features in ﬁve boreholes (Fig. 24) has been described by Velasco−Villareal et al. drilled around the Kardla€ impact meteorite structure (2011). where breccias are common. Quartz grains with planar

Fig. 23 Location of drill boreholes in the Chicxulub Impact Crater showing the position of Yaxcopoil-1 borehole in the southern sector of the crater. Figure from Velasco-Villareal et al. (2011), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943800650414. License Date: September 7, 2016.

deformation features and planar fractures, as well as suite of hydrothermal minerals deposited at different cracked grains showing lowered crystallinity by X-ray stages in the development of the hydrothermal diffractometry, were recorded. system. Meteorite Impact Site (Late Cambrian−Early Ordo- Moon and other planetary bodies: Meyer (2003) vician), Permian Basin, Texas: Malone (2015) suggested compiled an excellent collection of samples of lunar a meteorite impact crater involving shattered base- breccias. These breccias are the lithified aggregates of ment rock and ejecta, which is positioned ideally for clastic debris and melt generated by meteorite its petroleum potential. bombardment of the lunar surface. Most of the brec- Haughton impact structure, Devon Island, Cana- cias returned by the Apollo missions were formed in dian Arctic: According to Osinski et al. (2005),a the ancient lunar highlands about 3900e4000 million moderate- to low-temperature hydrothermal system years ago. Meyer (2003) also illustrated the geologic was generated at Haughton by the interaction of setting of craters (Fig. 27A) and proposed an inverse groundwaters with the hot impact melt breccias that stratigraphy on the crater rim (Fig. 27B). filled the interior of the crater (Fig. 26). Four distinct settings and styles of hydrothermal mineralization are 4.5. Sedimentary breccias recognized at Haughton: 1) vugs and veins within the impact melt breccias, with an increase in intensity of There are many types of sedimentary breccias, alteration towards the base; 2) cementation of brec- namely: ciated lithologies in the interior of the central uplift; 3) intense veining around the heavily faulted 1) Depositional breccias in subaerial environments and fractured outer margin of the central uplift; (e.g., alluvial fans; McPherson et al., 1987); brec- and 4) hydrothermal pipe structures or gossans and cias associated with lahars can be classified both as mineralization along fault surfaces around the faulted volcanic breccias and as sedimentary breccias crater rim. Each setting is associated with a different (Fig. 21).

Fig. 24 Impact breccia sequence, composed of six parts, in the Yaxcopoil-1 borehole. See Stoefﬂer et al. (2004) for original core photo- graphs. Figure from Velasco-Villareal et al. (2011), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3943800650414. License Date: September 7, 2016.

2) Depositional breccias in marginal-marine environ- 2016). In this review, sedimentary-depositional and ments (e.g., fan deltas and braid deltas; McPherson sedimentary-collapse types are considered. et al., 1987)(Fig. 28). In South China near Guilin, for example, some of 3) Depositional breccias in deep-marine environments the best developed karst topography with tower karsts (Shanmugam, 2012a)(Fig. 29). and large caves are evident (Shanmugam, 1990; 4) Post-depositional breccias (Shanmugam, 2016). Sweeting, 1978; Williams, 1978). Inside these modern 5) Non-depositional breccias (Blount and Moore, caves, a combination of factors, such as dissolution of 1969). carbonate rocks and fracturing, have led to accumu- 6) Karst-related collapse breccias in caves (Friedman, lation of collapse breccias on the ﬂoor of the caves 1997; Loucks, 2001). Synonyms for collapse brec- (Fig. 30). Paleocave breccia types are discussed by cias are solution or dissolution breccias, karst Loucks (2001) and by Loucks and Mescher (2001) breccias, and cave breccias. (Fig. 31). The economic importance of collapse breccias associated with uranium deposits in pipes is dis- A common type of sedimentary breccia is the one cussed by Finch (1992) (Fig. 32). The Orphan lode associated with mass-transport deposits (MTD), such as mine, located within the Grand Canyon National Park debris ﬂows in subaerial (Fig. 21), marginal-marine in Arizona (USA), produced 4.6 million pounds of Tri-

(Fig. 28), and deep-marine environments (Fig. 29) uranium octoxide (U3O8) with an average grade of (Shanmugam, 2012a). Furthermore, sedimentary brec- 0.42% of U3O8 from a mineralized, collapse-breccia cias can be grouped into two other types: 1) deposi- pipe during 1956e1969 (Chenoweth, 1986). tional (i.e., breccias formed during deposition), and 2) Typical diameter of a solution pipe with uranium post-depositional (i.e., breccias formed after deposi- ore is about 100 m (Fig. 32). Wenrich and Titley (2008) tion during burial and sediment loading) (Shanmugam, proposed a genetic model in which uranium

Fig. 25 A − Stratigraphic column showing traditional divisions of Alamo Breccia (Devonian) with megabreccia. Figure from Warme and Morrow (2009);B− Study area in Nevada (USA) showing towns (squares), Devonian localities (x's), and lateral distribution zones of Alamo Breccia. Breccia thicknesses: Zone 1, ~130 m; Zone 2, ~60 m; Zone 3, <1e10 m. Figure from Warme and Sandberg (1996);C− Outcrop photograph showing disintegrating clast in Alamo Breccia. Figure from Warme and Morrow (2009).

Fig. 26 A schematic cross-section showing the nature of the hydrothermal system shortly after the Haughton impact event. Figure from Osinski et al. (2005). mineralization is attributed to the Mississippi Valley 3) They are hosted mainly by dolostone and limestone. Type (MVT) deposits, with a uranium overprint. Char- 4) The dominant minerals are sphalerite ((Zn,Fe)S), acteristics of MVT deposits were discussed by Leach galena (PbS), pyrite (FeS2), and marcasite (FeS2). et al. (2010). Important properties are that: 5) They occur in platform carbonate sequences. 6) The ore ﬂuids were basinal brines with ~10e30 wt. 1) They are epigenetic. percent salts. 2) They are not associated with igneous activity. 7) They have crustal sources for metals and sulfur.

Fig. 27 A − Geological setting of impact breccias in a giant impact crater; B − The material that is thrown out of the crater is deposited in a reverse stratigraphy (shown by numbers 1, 2, and 3) on the rim of the crater. Both ﬁgures are from Meyer (2003). Credit: NASA.

Fig. 28 Sedimentary−depositional breccia showing inverse grading (arrow), suggesting deposition from debris ﬂows. There is an abun- dance of blueschist and other metamorphic clasts. This stratum has been interpreted as fan−delta deposits (Stuart, 1979). San Onofre Breccia, Miocene, Dana Point, California. Red scale (center of photo) = 15 cm. Figure from Shanmugam (2012a), with permission from Elsevier. Copyright Clearance Center's RightsLink: Licensee: G. Shanmugam. License Number: 3950801388442. License Date: September 16, 2016.

Fig. 29 An example of sedimentary−depositional breccia: Pliocene reservoir sands in upper-slope canyon environments, offshore Krish- na−Godavari (KG) Basin, India. A − Sedimentological log of core 7 for the interval 2115e2121 m in well 3 showing massive sand with ﬂoating brecciated mudstone clasts; B − Lithofacies 1 core photograph showing brecciated mudstone clasts. Arrow shows stratigraphic position of photograph. Figure from Shanmugam et al., (2009). Credit: SEPM.

4.6. Implications

Major differences among the ﬁve types of breccias and their implications are as follows:

1) In general, meteorite breccias are distinguished by their shock features (e.g., planar deformation in mineral grains, high-pressure polymorphs, shock melts, etc.) from fault breccias, which are formed much more slowly and do not have shock features. However, ejecta-related breccias that do not exhibit melt features are difficult to distinguish from sedimentary−depositional breccias. Also, Maddock (1983) reported fault-generated pseudo- Fig. 30 Development of large caves in the Devonian−Upper tachylytes from the Outer Hebrides Thrust Zone, Carboniferous carbonates as part of karst topography near Guilin, Scotland, and explained that the textures were along the banks of Li River, Southern China. Note collapse breccia on resulted from the primary crystallization of a clast- the floor at water level. Figure modified after Shanmugam (1990), laden melt rather than from the devitrification of a with permission from AAPG. glass, or from crushing and cataclasis. 2) Meteorite breccias are associated with hydrothermal activity, whereas most sedimentary breccias 8) Temperatures of ore deposition are typically 75 C are not. However, hydrothermal breccias in vein- to about 200 C. type ore deposits are present (Jebrak, 1997). 9) The most important ore controls are faults and 3) Sedimentary breccias are indicative of primary fractures, and dissolution collapse breccias. porosity and permeability, whereas meteorite

Fig. 31 Paleocave facies showing breccia types. Figure from Loucks (2001).

breccias commonly are subjected to high pressure 7) In basin analysis, karst breccias are useful in and high temperature melt events. recognizing erosional unconformities (Shanmugam, 4) Although sedimentary breccias of different origins 1988). may look alike, recognizing breccias in sol- 8) Sedimentary breccias are subjected to sediment ution−collapse pipes is vital because of their asso- transport and indicative of a variable sediment ciation with uranium deposits (Fig. 32). provenance, whereas meteorite breccias are 5) Analogous to leaching conditions that developed commonly local in origin. caves in South China (Fig. 30), porosity enhance- 9) Fault breccias and sedimentary breccias exhibit ment from chert dissolution beneath Neocomian normal stratigraphy, whereas meteorite breccias unconformity had resulted in favorable reservoir are associated with reverse stratigraphy of the quality in the Prudhoe Bay Field (i.e., the Ivishak crater rim. Formation), North Slope, Alaska (Shanmugam and Higgins, 1988). Perhaps the most important implication is that it is 6) Deep-water sandy debrites, with depositional fundamentally a challenge to interpret the origin of breccias (Fig. 29), comprise important petroleum breccias. As discussed earlier, the same breccias have reservoirs worldwide (Shanmugam, 2012a; been interpreted differently by different authors Shanmugam et al., 2009). as karst breccias, fault breccias, and “explosion”

Fig. 32 Schematic cross section of a solutionecollapse breccia pipe in the Grand Canyon Region (USA) showing the distribution of uranium ore (U ore) in the pipe. Pipe height and diameter are about 915 m and 100 m, respectively. Stratigraphic section modiﬁed after Van Gosen and Wenrich (1989). Figure from Finch (1992). Credit: USGS. See also Dahlkamp (1990).

Fig. 33 Summary diagram showing that SSDS with breccias can be interpreted as ﬁve different types with different implications. Note that sedimentary−depositional breccias are the only type that preserves the depositional porosity and permeability at the time of deposition without diagenesis. However, sedimentary breccias are subjected to post-depositional diagenesis. For example, all ﬁve types are susceptible to develop secondary porosity (Shanmugam, 1985). volcanic megabreccias in South Wales (Fig. 20B). sedimentaryedepositional breccias) has practical im- Furthermore, megabreccias have been associated with plications for stratigraphy, sedimentology, prove- both faulting (Woodcock et al., 2014) and meteorite nance, diagenesis, and reservoir quality. In moving impacts (Warme and Morrow, 2009). Therefore, clas- forward, it is necessary to abandon the current prac- sifying SSDS with breccias as “seismites” unnecessarily tice of interpreting SSDS as seismites routinely. distracts from the primary objective of establishing the true origin of breccias (Fig. 33), which has direct implications for understanding petroleum reservoirs Acknowledgements (Fig. 29) and economic ore deposits (Fig. 32).

I thank Prof. Zeng-Zhao Feng (Editor-in-Chief of the 5. Concluding remarks Journal of Palaeogeography; China University of Pe- troleum, Beijing) for inviting me to contribute my “ ” The purpose of interpreting SSDS as seismites is to earlier review entitled The seismite problem and for explain the precise origin of their deformation. How- encouraging me to write this companion paper as well. ever, seismicity is omnipresent worldwide and is I also thank the JoP editor Dr. Xiu-Fang Hu for her help associated with a multitude of phenomena, namely with solving submission-related computer problems global tectonics, meteorite impacts, volcanic phe- and for her initial work during submission process. I nomena, oceanographic (tsunami) phenomena, mete- thank the editor Dr. Min Liu (Amy) for her excellent orologic (cyclone) phenomena, and eustatic (sea level) editing of the manuscript. events. Therefore, naming SSDS simply as “seismites”, Prof. Tian-Rui Song, Institute of Geology, Chinese without identifying the true cause of the seismic Academy of Geological Sciences, Beijing; Prof. Hong- shocks, is fallacious. Importantly, distinguishing Bo Lü, Department of Geology, China University of the correct origin of SSDS (e.g., meteorite versus Petroleum, Shandong Province; Dr. D.W. Kirkland,

Please cite this article in press as: Shanmugam, G., The fallacy of interpreting SSDS with different types of breccias as seismites amid the multifarious origins of earthquakes: Implications, Journal of Palaeogeography (2016), http://dx.doi.org/10.1016/j.jop.2016.09.001 The fallacy of interpreting SSDS with different types of breccias 29 retired Research Scientist from Mobil Oil Corporation, triggers margin collapse and extensive sediment gravity Texas; and an anonymous reviewer are thanked for flows. Geology, 26, 331e334. their detailed and helpful comments that considerably Brothers, D.S., Luttrell, K.M., Chaytor, J.D., 2013. Sea- improved the quality of this paper. As always, I am level-induced seismicity and submarine landslide occurrence. Geology, 41, 979e982. grateful to my wife, Jean Shanmugam, for her general Busby, C.J., Yip, G., Blikra, L., Renne, P., 2002. Coastal land- comments. sliding and catastrophic sedimentation triggered by Cre- taceous−Tertiary bolide impact: a pacific margin example? Geology, 30, 687e690. References Caine, J.S., Evans, J.P., Forster, C.B., 1996. Fault zone ar- chitecture and permea bility structure. Geology, 24, 1025e1028. Agnon, A., Migowski, C., Marco, S., 2006. Intraclast breccias Chenoweth, W.I., 1986. The Orphan Lode Mine, Grand in laminated sequences reviewed: recorders of paleo- Canyon, Arizona: a Case Study of a Mineralized, earthquakes. In: Enzel, Y., Agnon, A., Stein, M. (Eds.), Collapse-breccia Pipe. U.S. Geological Survey Open File Frontiers in Dead Sea Paleoenvironmental Research, Report, pp. 86e510. vol. 401. GSA Special Paper, pp. 195e214. Claeys, P., Kiessling, W., Alvarez, W., 2002. Distribution of Allen, C.R., 1975. Geological criteria for evaluating seis- Chicxulub ejecta at the Cretaceous−Tertiary boundary. micity. GSA Bulletin, 86, 1041e1057. In: Koeberl, C., MacLeod, K.G. (Eds.), Catastrophic Allen, J.R.L., 1984. Sedimentary Structures, Their Char- Events and Mass Extinctions: Impacts and beyond, vol. acter and Physical Basis. I, p. 593 and II, pp. 343−663. 356. GSA Special Paper, pp. 55e68. Elsevier, Amsterdam. Collins, G.S., Melosh, H.J., Marcus, R.A., 2005. Earth impact ASCE (American Society of Civil Engineers), 1907. The Ef- effects program: a web-based computer program for fects of the San Francisco Earthquake of April 18th, calculating the regional environmental consequences of 1906, on Engineering Constructions: Reports of a General a meteoroid impact on Earth. Meteoritics & Planetary Committee and of Six Special Committees of the San Science, 40, 817e840. Francisco Association of Members of the American Soci- Collinson, J.D., 1994. Sedimentary deformational struc- ety of Civil Engineers. Transactions. Paper No. 1056. tures. In: Maltman, A. (Ed.), The Geological Deformation Barruol, G., Cordier, E., Bascou, J., Fontaine, F.R., of Sediments. Chapman & Hall, London, pp. 95e125. Legresy, B., Lescarmontier, L., 2013. Tide-induced micro- Covey, C., Thompson, S.L., Weissman, P.R., seismicity in the Mertz glacier grounding area, East MacCracken, M.C., 1994. Global climatic effects of atmo- Antarctica. Geophysical Research Letters, 40, spheric dust from an asteroid or comet impact on Earth. 5412e5416. Global Planetary Change, 9, 263e273. Basilone, L., Lena, G., Gasparo-Morticelli, M., 2014. Synse- Dahlkamp, F.J., 1990. Uranium deposits in collapse breccia dimentary-tectonic, soft-sediment deformation and pipes in the Grand canyon region, Colorado plateau, volcanism in the rifted Tethyan margin from the upper USA. Mitteilungen des Naturwissenschaftlichen Vereines Triassicemiddle Jurassic deep-water carbonates in cen- für Steiermark, 120, 89e98. tral Sicily. Sedimentary Geology, 308, 63e79. Day, S., Maslin, M., 2005. Linking large impacts, gas hy- Beck, C., 2009. Lake sediments as late quaternary palaeo- drates, and carbon isotope excursions through widespread seismic archives: examples in northewestern alps and sediment liquefaction and continental slope failure: the clues for earthquake-origin assessment of sedimentary example of the K−T boundary event. In: Kenkmann, T., disturbances. Earth-Science Reviews, 96, 327e344. Horz,€ F., Deutsch, A. (Eds.), Large Meteorite Impacts III, Becker, L., 2002. Repeated blows. Scientific American, 286, vol. 384. GSA Special Paper, pp. 239e258. 76e83. Dixon, E.E.L., 1921. The Geology of the South Wales Coal- Bischoff, A., 2000. Mineralogical characterization of primi- field, Part XIII: the Country around Pembroke and tive, type-3 lithologies in Rumuruti chondrites. Meteor- Tenby. In: Memoir, Geological Survey of the United itics & Planetary Science, 35, 699e706. Kingdom. Her (His) Majesty's Stationery Office Bischoff, A., Scott, E.R.D., Metzler, K., Goodrich, C.A., (H.M.S.O.). 2006. Nature and origins of meteoritic breccias. In: Egholm, D.G., Clausen, O.R., Sandiford, M., Lauretta, D.S., McSweeen Jr., H.Y. (Eds.), Meteorites Kristensen, M.B., Korstgard, J.A., 2008. The mechanics and the Early Solar System II. University of Arizona of clay smearing along faults. Geology, 36, 787e790. Press, pp. 679e712. Engelder, J.T., 1974. Cataclasis and the generation of fault Blount, D., Moore, C.H., 1969. Depositional and non- gouge. GSA Bulletin, 85, 1515e1522. depositional carbonate breccias, Chiantla quadrangle, Finch, W.I., 1992. Descriptive model of solutionecollapse Guatemala. GSA Bulletin, 80, 429e442. breccia pipe uranium deposits. U.S. Geological Survey Boulton, G.S., Dobbie, K.E., Zatsepin, S., 2001. Sediment Bulletin, 2004. In: Bliss, J.D. (Ed.), Developments in Min- deformation beneath glaciers and its coupling to the sub- eral Deposit Modelling, pp. 33e35. glacial hydraulic system. Quaternary International, 86, Fisher, R.V., 1960. A classification of volcanic breccias. GSA 3e28. Bulletin, 71, 973e982. Bralower, T.J., Paull, C.K., Leckie, R.M., 1998. The Creta- Fisher, R.V., 1983. Flow transformations in sediment gravity ceous−Tertiary boundary cocktail: Chicxulub impact flows. Geology, 11, 273e274.

Fisher, R.V., 1984. Pyroclastic Rocks. Springer-Verlag, Berlin changes in minerals in the sandy ejecta of the Kardla€ Heildelberg, p. 472. crater, NW Estonia. Proceedings of the Estonian Academy Fjeldskaar, W., Lindholm, C., Dehls, J.F., Fjeldskaar, I., of Sciences. Geology, 55, 189e212. 2000. Postglacial uplift, neotectonics and seismicity in Knipe, R.J., Jones, G., Fisher, Q.J., 1998. Faulting, fault Fennoscandia. Quaternary Science Reviews, 19, sealing and fluid flow in hydrocarbon reservoirs: an intro- 1413e1422. duction. In: Jones, G., Fisher, Q.J., Knipe, R.J. (Eds.), Friedman, G.M., 1997. Dissolution-collapse breccias and Faulting Fault Sealing and Fluid Flow in Hydrocarbon paleokarst resulting from dissolution of evaporite rocks, Reservoirs, 147. Geological Society of London, Special especially sulfates. Carbonates and Evaporites, 12, Publication, pp. 7e21. 53e63. Lahr, J.C., Chouet, B.A., Stephens, C.D., Power, J.A., Geist, E.L., 2005. Local Tsunami Hazards in the Pacific Page, R.A., 1994. Earthquake classification, location, Northwest from Cascadia Subduction Zone Earthquakes. and error analysis in a volcanic environment: implications U.S. Geological Survey Professional Paper, 1661-B, p. 17. for the magmatic system of the 1989−1990 eruptions at Goslin, J., Lourenco, N., Dziak, R.P., Bohnenstiehl, D.R., Redoubt Volcano, Alaska. Journal of Volcanology and Haxel, J., Luis, J., 2005. Long-term seismicity of the Rey- Geothermal Research, 62, 137e151. kjanes Ridge (North Atlantic) recorded by a regional hy- Leach, D.L., Taylor, R.D., Fey, D.L., Diehl, S.F., Saltus, R.W., drophone array. Geophysical Journal International, 162, 2010. A deposit model for Mississippi Valley-Type lead- 516e524. zinc ores: chapter A. In: Mineral Deposit Models for Gradmann, S., Beaumont, C., Ings, S.J., 2012. Coupled fluid Resource Assessment. USGS Scientific Investigations flow and sediment deformation in margin-scale salt-tec- Report 2010-5070-A, p. 64. http://pubs.usgs.gov/sir/ tonic systems: 1. Development and application of simple, 2010/5070/a/pdf/SIR10-5070A.pdf (Accessed 7 October single-lithology models. Tectonics, 31. TC4010. 2016). Grajales-Nishimura, J.M., Cedillo-Pardo, E., Rosales- Logan, W.E., 1863. Report on the Geology of Canada. John Domínguez, C., Moran-Zenteno, D., Alvarez, W., Lovell, Montreal, Canada, p. 464. Claeys, P., Ruíz-Morales, J., García-Hernandez, J., Loucks, R.G., 2001. Modern analogs for paleocave-sediment Padilla-Avila, P., Sanchez-Ríos, A., 2000. Chicxulub fills and their importance in identifying paleocave reser- impact: the origin of reservoir and seal facies in the voirs. Transactions-Gulf Coast Association of Geological southeastern Mexico oil fields. Geology, 28, 307e310. Societies, 46, 195e206. Greb, S.F., Archer, A.W., 2007. Soft-sediment deformation Loucks, R.G., Mescher, P., 2001. Paleocave facies classifi- produced by tides in a meizoseismic area, Turnagain cation and associated pore types. In: American Associ- Arm, Alaska. Geology, 35, 435e438. ation of Petroleum Geologists, Southwest Section, Greene, M., Power, M., Youd, T.L., 1994. Earthquake basics Annual Meeting, Dallas, Texas, March 11e13, CD- Brief No. 1. Earthquake Engineering Research Institute ROM,p.18. Publication, Oakland, California, p. 8. Lowman, P., Yates, J., Masuoka, P., Montgomery, B., Hancock, P.L., 1964. The relations between folds and late- O'Leary, J., Salisbury, D., 1999. A digital tectonic activity formed joints in South Pembrokeshire. Geological Maga- map of the Earth. Journal of Geoscience Education, 47, zine, 101, 174e184. 428e437. Head III, J.W., Wilson, L., 2003. Deep submarine pyroclastic Maddock, R.H., 1983. Melt origin of fault-generated pseudo- eruptions: theory and predicted landforms and deposits. tachylites demonstrated by textures. Geology, 11, Journal of Volcanology and Geothermal Research, 121, 105e108. 155e193. Malone, S.J., 2015. Discovery of a Probable Meteorite Helwig, J., 1970. Slump folds and early structures, north- Impact Site of Late Cambrian−Early Ordovician Age in eastern Newfoundland Appalachians. Journal of Geology, the Permian Basin, Crockett County, Texas, and its Impli- 78, 172e187. cations for Hydrocarbon Exploration. Search and Discov- Holzer, T.L., Youd, T.L., 2007. Liquefaction, ground oscilla- ery Article, No. 10719 (2015). tion, and soil deformation at the Wildlife Array, Califor- Malkawi, A.I.H., Alawneh, A.S., 2000. Paleoearthquake fea- nia. Bulletin of the Seismological Society of America, tures as indicators of potential earthquake activities in 97, 961e976. the Karameh Dam Site. Natural Hazards, 22, 1e16. Isacks, B., Oliver, J., Sykes, L.R., 1968. Seismology and the Maltman, A., 1984. On the term soft-sediment deformation. new global tectonics. Journal of Geophysical Research- Journal of Structural Geology, 6, 589e592. Atmospheres, 73, 5855e5899. Maltman, A., 1994. Introduction and overview. In: Jebrak, M., 1997. Hydrothermal breccias in vein-type ore Maltman, A. (Ed.), The Geological Deformation of Sedi- deposits: a review of mechanisms, morphology and size ments. Chapman & Hall, London, pp. 1e35. distribution. Ore Geology Reviews, 12, 111e134. Marcus, R., Melosh, H.J., Collins, G., 2010. Earth Impact Ef- Kearey, P., Klepeis, K.A., Vine, F.J., 2009. Global Tectonics, fects Program. Imperial College, London, UK, and Purdue third ed. Wiley-Blackwell, p. 496. University. Kirkland, D.W., Anderson, R.Y., 1970. Microfolding in the McPherson, J.G., Shanmugam, G., Moiola, R.J., 1987. Fan- Castile and Todilto evaporites, Texas and New Mexico. deltas and braid deltas: varieties of coarse-grained GSA Bulletin, 81, 3259e3282. deltas. GSA Bulletin, 99, 331e340. Kleesment, A., Konsa, M., Puura, V., Karhu, J., Preeden, U., Melosh, B.L., Rowe, C.D., Smit, L., Groenewald, C., Kallaste, T., 2006. Impact-induced and diagenetic Lambert, C.W., Macey, P., 2014. Snap, Crackle, Pop:

dilational fault breccias record seismic slip below the Earthquake of April 18, 1906, vol. 2. Carnegie Institution brittle-plastic transition. Earth and Planetary Science of Washington, Washington, D.C., 1910. Letters, 403, 432e445. Roman, D.C., Cashman, K.V., 2006. The origin of volcano- Meng, X., Peng, Z., Yang, H., Allman, S., 2013. Hurricane tectonic earthquake swarms. Geology, 34, 457e460. Irene's Impacts on the Aftershock Sequence of the 2011 Rowe, C.D., Melosh, B.L., Lamothe, K., Schnitzer, V., Mw5.8 Virginia Earthquake. American Geophysical Bate, C., 2013. Earthquake Breccias (Invited). American Union, Fall Meeting 2013, Abstract# S51B-2369. Geophysical Union, Fall Meeting 2013, Abstract # T52A-01. Meyer, C., 2003. Lunar breccia. In: NASA Lunar Petrographic Ruff, L.J., 1996. Large earthquakes in subduction zones. In: Educational Thin Section Set. http://www-curator.jsc. Bebout, G.E., Scholl, D.W., Kirby, S.H., Platt, J.P. (Eds.), nasa.gov/Education/LPETSS/index.cfm (Accessed 20 Subduction Top to Bottom. Geophysical Monograph Se- July 2016). ries, first ed., pp. 91e104. Minor, S.A., Hudson, M.R., 2006. Regional Survey of Struc- Rundquist, D.V., Sobolev, P.O., 2002. Seismicity of mid- tural Properties and Cementation Patterns of Fault oceanic ridges and its geodynamic implications: a review. Zones in the Northern Part of the Albuquerque Basin, Earth-Science Reviews, 58, 143e161. New Mexico: Implications for Ground-water Flow. U.S. Sakaguchi, A., Kimura, G., Strasser, M., Screaton, E.J., Geological Survey Professional Paper, 1719, p. 32. Curewitz, D., Murayama, M., 2011. Episodic seafloor Moran, S.C., Malone, S.D., Qamar, A.I., Thelen, W., mud brecciation due to great subduction zone earth- Wright, A.K., Caplan-Auerback, J., 2008. Seismicity asso- quakes. Geology, 39, 919e922. ciated with the renewed dome-building at Mount St. Hel- Scholz, C.H., 1990. The Mechanics of Earthquakes and ens, 2004−2008. U.S. Geological Survey Professional Faulting. Cambridge University Press, New York, Paper, 1750. In: Sherrod, D.R., Scott, W.E., p. 439. Stauffer, P.H. (Eds.), A Volcano Rekindled: the Renewed Scholz, H., Frieling, D., Aehnelt, M., 2011. Synsedimentary Eruption of Mount St. Helens, 2004e2006. deformational structures caused by tectonics and seismic NGDC/WDS (National Geophysical Data Center/World Data events d examples from the Cambrian of Sweden, Service), 2016. Significant Earthquake Database. Na- Permian and Cenozoic of Germany. In: Sharkov, E. (Ed.), tional Geophysical Data Center, NOAA. http:// New Frontiers in Tectonic Research d General Problems, dx.doi.org/10.7289/V5TD9V7K (Accessed 27 July 2016). Sedimentary Basins and Island Arcs, Chapter 9, Norris, R.D., Firth, J.V., 2002. Mass wasting of Atlantic con- pp. 183e218. tinental margins following the Chicxulub impact event. Schulte, P., Alegret, L., Arenillas, I., Arz, J.A., Barton, P.J., In: Koeberl, C., MacLeod, K.G. (Eds.), Catastrophic Bown, P.R., Bralower, T.J., Christeson, G.L., Claeys, P., Events and Mass Extinctions: Impacts and beyond, vol. Cockell, C.S., Collins, G.S., Deutsch, A., Goldin, T.J., 356. GSA Special Paper, pp. 79e95. Goto, K., Grajales-Nishimura, J.M., Grieve, R.A.F., Obermeier, S., Pond, E., Olson, S., Green, R., 2002. Paleoli- Gulick, S.P.S., Johnson, K.R., Kiessling, W., Koeberl, C., quefaction studies in continental settings, vol. 359. GSA Kring, D.A., MacLeod, K.G., Matsui, T., Melosh, J., Special Paper, pp. 13e27. Montanari, A., Morgan, J.V., Neal, C.R., Nichols, D.J., Obermeier, S.F., Olson, S.M., Green, R.A., 2005. Field occur- Norris, R.D., Pierazzo, E., Ravizza, G., Rebolledo- rences of liquefaction-induced features: a primer for en- Vieyra, M., Reimold, W.U., Robin, E., Salge, T., gineering geologic analysis of paleoseismic shaking. Speijer, R.P., Sweet, A.R., Urrutia-Fucugauchi, J., Engineering Geology, 76, 209e234. Vajda, V., Whalen, M.T., Willumsen, P.S., 2010. The chic- Osinski, G.R., Lee, P., Parnell, J., Spray, J.G., Baron, M., xulub asteroid impact and mass extinction at the Creta- 2005. A case study of impact-induced hydrothermal ac- ceous−Paleogene boundary. Science, 327, 1214e1218. tivity: the Haughton impact structure, Devon Island, Ca- Seilacher, A., 1969. Fault-graded beds interpreted as seismi- nadian High Arctic. Meteoritics & Planetary Science, 40, tes. Sedimentology, 13, 155e159. 1859e1877. Shanmugam, G., 1985. Types of porosity in sandstones and Pankow, K.L., Moore, J.R., Hale, J.M., Koper, K.D., their significance in interpreting provenance. In: Kubacki, T., Whidden, K.M., McCarter, M.K., 2014. Zuffa, G.G. (Ed.), Provenance of Arenites. D. Reidel Pub- Massive landslide at Utah copper mine generates wealth lishing Company, Holland, pp. 115e137. of geophysical data. GSA Today, 24, 9. Shanmugam, G., 1988. Origin, recognition and importance Parsons, T., Geist, E.L., Ryan, H.F., Lee, H.J., of erosional unconformities in sedimentary basins. In: Haeussler, P.J., Lynett, P., Hart, P.E., Sliter, R., Kleinspehn, K.L., Paola, C. (Eds.), New Perspectives Roland, E., 2014. Source and progression of a submarine in Basin Analysis. Springer-Verlag, New York, landslide and tsunami: the 1964 Great Alaska earthquake pp. 83e108. at Valdez. Journal of Geophysical Research Solid Earth, Shanmugam, G., 1990. Porosity prediction in sandstones 119. http://dx.doi.org/10.1002/2014JB011514. using erosional unconformities. In: Meshri, I.D., Pinto, J.A., Warme, J.E., 2008. Alamo Event, Nevada: crater Ortoleva, P.J. (Eds.), Prediction of Reservoir Quality stratigraphy and impact breccia realms. In: Evans, K.R., through Chemical Modelling, vol. 49. AAPG Memoir, Horton Jr., J.W., King Jr., D.T., Morrow, J.R. (Eds.), The pp. 1e23. Sedimentary Record of Meteorite Impacts, vol. 437. Shanmugam, G., 2006a. Deep-water processes and facies GSA Special Paper, pp. 99e137. models: implications for sandstone petroleum reservoirs. Reid, H.F., 1910. Report of the State Investigation Commis- In: Handbook of Petroleum Exploration and Production, sion. The Mechanics of the Earthquake, the California vol. 5. Elsevier, Amsterdam, p. 476.

Shanmugam, G., 2006b. The tsunamite problem. Journal of The Cretaceous−Tertiary Event and Other Catastrophes Sedimentary Research, 76, 718e730. in Earth History, vol. 307. GSA Special Paper, Shanmugam, G., 2008a. Deep-water bottom currents and pp. 151e182. their deposits. In: Rebesco, M., Camerlenghi, A. (Eds.), Steer, P., Simoes, M., Cattin, R., Shyu, J.B.H., 2014. Erosion Developments in Sedimentology, Chapter 5, Contourites, influences the seismicity of active thrust faults. Nature vol. 60. Elsevier, Amsterdam, pp. 59e81. Communications, 5, 5564. Shanmugam, G., 2008b. The constructive functions of trop- Stoeffler, D., Artemieva, N.A., Ivanov, B.A., Hecht, L., ical cyclones and tsunamis on deepwater sand deposition Kenkemann, T., Schmitt, R.T., Tagle, R.A., during sea level highstand: implications for petroleum Wittmann, A., 2004. Origin and emplacement of the exploration. AAPG Bulletin, 92, 443e471. impact formations at Chicxulub, Mexico, as revealed by Shanmugam, G., 2012a. New perspectives on deep-water the ICDP deep drilling at Yaxcopoil-1 and by numerical sandstones: origin, recognition, initiation, and reservoir modeling. Meteoritics & Planetary Science, 39, quality. In: Handbook of Petroleum Exploration and Pro- 1035e1067. duction, vol. 9. Elsevier, Amsterdam, p. 524. Stover, C.W., Coffman, J.L., 1993. Seismicity of the United Shanmugam, G., 2012b. Process-sedimentological chal- States, 1568−1989 (Revised). U.S. Geological Survey Pro- lenges in distinguishing paleo-tsunami deposits. Natural fessional Paper 1527. United States Government Printing Hazards, 63, 5e30. Office, p. 72, 101, 102. Shanmugam, G., 2013a. Comment on “Internal waves, an Stuart, C.J., 1979. Lithofacies and origin of the San Onofre underexplored source of turbulence events in the sedi- Breccia, coastal southern California. In: Stuart, C.J. mentary record” by L. Pomar, M. Morsilli, P. Hallock, (Ed.), Miocene Lithofacies and Depositional Environ- and B. Badenas [Earth-Science Reviews, 111 (2012), ments, Coastal Southern California and Northwestern 56e81]. Earth-Science Reviews, 116, 195e205. Baja California: Pacific Section. Society of Economic Pa- Shanmugam, G., 2013b. Modern internal waves and internal leontologists and Mineralogists, pp. 25e42. tides along oceanic pycnoclines: challenges and implica- Sweeting, M.M., 1978. The karst of Kweilin, Southern China. tions for ancient deep-marine baroclinic sands. AAPG Geographical Journal, 144, 199e204. Bulletin, 97, 767e811. Tappin, D.R., Grilli, S.T., Harris, J.C., Geller, R.J., Shanmugam, G., 2015. The landslide problem. Journal of Masterlark, T., Kirby, J.T., Shi, F., Ma, G., Palaeogeography, 4, 109e166. Thingbaijam, K.K., Mai, P.M.,2014. Did a submarine land- Shanmugam, G., 2016. The seismite problem. Journal of slide contribute to the 2011 Tohoku tsunami? Marine Ge- Palaeogeography, 5, 318e362. ology, 357, 344e361. Shanmugam, G., Higgins, J.B., 1988. Porosity enhancement Tappin, D.R., Watts, P., McMurtry, G.M., Lafoy, Y., from chert dissolution beneath Neocomian unconformity: Matsumoto, T., 2001. The Sissano, Papua New Guinea Ivishak Formation, North Slope, Alaska. AAPG Bulletin, tsunami of July 1998 d Offshore evidence on the source 72, 523e535. mechanism. Marine Geology, 175, 1e23. Shanmugam, G., Moiola, R.J., Sales, J.K., 1988. Duplex-like Tessier, B., Terwindt, J.H.J., 1994. Un exemple de structures in submarine fan channels, Ouachita Moun- deformations synsedimentaires en milieu intertidal l’ef- tains, Arkansas. Geology, 16, 229e232. fet du mascaret. Paris, Academie des Sciences Comptes Shanmugam, G., Shrivastava, S.K., Das, B., 2009. Sandy Rendus, 319, 217e223. debrites and tidalites of Pliocene reservoir sands in Thomas, T.M., 1970. Field meeting of the South Wales group upper-slope canyon environments, Offshore Krishna−Go- on the Stack rocks to Bullslaughter Bay section of the davari Basin (India): Implications. Journal of Sedimentary South Pembrokeshire coast. Proceedings of the Geolo- Research, 79, 736e756. gists Association, 81, 241e248. Shoemaker, E., 1983. Asteroid and comet bombardment of Tilling, R.I., Topinka, L., Swanson, D.A., 1990. Eruptions of the Earth. Annual Review of Earth and Planetary Sci- Mount St. Helens: Past, Present, and Future. U.S. ences, 11, 461e494. Geological Survey Special Interest Publication. U.S. Sibson, R.H., 1977. Fault rocks and fault mechanisms. Geological Survey, Vancouver, WA, p. 56. Journal of the Geological Society of London, 133, Tryggvason, E., 1973. Seismicity, earthquake swarms, and 191e213. plate boundaries in the Iceland region. Bulletin of the Sibson, R.H., 1986. Brecciation processes in fault zones: in- Seismological Society of America, 63, 1327e1348. ferences from earthquake rupturing. Pure and Applied USGS (U.S. Geological Survey), 2016. Earthquake Hazards Geophysics, 124, 159e174. Program. Earthquake Glossary d Earthquake. http:// Simms, M.J., 2003. Uniquely extensive seismite from the earthquake.usgs.gov/learn/glossary/?term=earthquake latest Triassic of the United Kingdom: evidence for bolide (Accessed 18 July 2016). impact? Geology, 31, 557e560. Van Gosen, B.S., Wenrich, K.J., 1989. Ground Magnetom- Smit, J., Roep, ThB., Alvarez, W., Montanari, A., Claeys, P., eter Surveys over Known and Suspected Breccia Pipes Grajales-Nishimura, J.M., Bermudez, J., 1996. Coarse- on the Coconino Plateau, Northwestern Arizona. U.S. grained, clastic sandstone complex at the Geological Survey Bulletin, 1683-C, p. 31. Cretaceous−Paleogene (K−Pg) boundary (formerly Velasco-Villareal, M., Urrutia-Fucugauchi, J., Rebolledo- known as the K−T boundary) around the Gulf of Mexico: Vieyra, M., Perez-Cruz, L., 2011. Paleomagnetism of deposition by tsunami waves induced by the Chicxulub impact breccias from the Chicxulub crater d implica- impact? In: Ryder, G., Gartner, S., Fastovsky, D. (Eds.), tions for ejecta emplacement and hydrothermal

processes. Physics of the Earth and Planetary Interiors, and consideration of genetic models. In: Spencer, J.E., 186, 154e171. Titley, S.R. (Eds.), Ores and Orogenesis: Circum-Paciﬁc Venzke, E., Wunderman, R.W., McClelland, L., Simkin, T., Tectonics, Geologic Evolution, and Ore Deposits, 22. Ari- Luhr, J.F., Siebert, L., Mayberry, G., Sennert, S., 2002. zona Geological Society Digest, pp. 295e309. Global Volcanism, 1968 to the Present, Global Volcanism West, M.E., Larsen, C.F., Truffer, M., O'Neel, S., LeBlanc, L., Program Digital Information Series, GVP-4. Smithsonian 2010. Glacier microseismicity. Geology, 38, 319e322. Institution, Washington, D.C.. http://www.volcano.si. Williams, P.F., 1978. Karst research in China. British Cave edu/reports/ Research Association Transactions,5,29e46. Waite, G.P., Chouet, B.A., Dawson, P.B., 2008. Eruption dy- Woodcock, N.H., Miller, A.V.M., Woodhouse, C.D., 2014. namics at Mount St. Helens imaged from broadband Chaotic breccia zones on the Pembroke Peninsula, south seismic waveforms: interaction of the shallow magmatic Wales: evidence for collapse into voids along dilational and hydrothermal systems. Journal of Geophysical faults. Journal of Structural Geology, 69, 91e107. Research-Atmospheres, 113(B2). B02305. Woodcock, N.H., Omma, J.E., Dickson, J.A.D., 2006. Walsh, P., Battiau-Queney, Y., Howells, S., Ollier, C., Chaotic breccia along the Dent Fault, NW England: implo- Rowberry, M., 2008. The gash breccias of the Pembroke sion or collapse of a fault void? Journal of the Geological Peninsula, SW Wales. Geology Today, 24, 137e145. Society London, 163, 431e446. Warme, J.E., Morrow, J.R., 2009. Alamo Impact Breccia: Yao, Y., Wang, Q., Li, J., Shen, X., Kong, Y., 2013. Seismic Ring Realm Processes and Products. Adapted from an hazard assessment of the three Gorges project. Geodesy oral presentation at AAPG Annual Convention and Exhibi- and Geodynamics,4,53e60. tion, Denver, Colorado, USA, June 7−10, 2009. Search and Zhang, Y., Person, M., Rupp, J., Ellett, K., Celia, M.A., Discovery Article #40494 (2010). Gable, C.W., Bowen, B., Evans, J., Bandilla, K., Warme, J.E., Sandberg, C.A., 1996. Alamo megabreccia. Mozley, P., Dewers, T., Elliot, T., 2013. Hydrogeologic GSA Today,6,1e7. controls on induced seismicity in crystalline basement Wenrich, K.J., Titley, S.R., 2008. Uranium exploration for rocks due to ﬂuid injection into basal reservoirs. Ground- northern Arizona (USA) breccia pipes in the 21st century water, 51, 525e538.