Does air-gun noise harm marine mammals?

Caldwell, Jack

doi:10.1190/1.1445856

Cited by 8 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many papers on this issue were published in various journals. But due to the insufficiency of the observation data nowadays, this kind of argument and discussions will last for a while [6] . An observation evidence, provided by Norwegian Oil Industry Association [7] and accepted by both sides of the argument, is that the physical damages to fish only happen within a few meters of the seismic source.…”

Section: Effect Of Airgun Shooting On the Fish In The Reservoirmentioning

confidence: 97%

“…The other basic circumstances ( Figure 1) are listed bellow: reservoir capacity: 36 million cubic meters (medium reservoir); dam type: rock-fill dam; water depth at shooting point: 18 m; sinking depth of airgun: Figure 1 The setup of the airgun source experiment conducted in the Shangguanhu Reservoir on July 25, 2006. Components of the experiment consist of the 35-MPa air compressor (1), the high-pressure air-bottles (2), the control panel (3), cables and air ducts (4), the float platform (5), the airguns (only one shown) (6), and the airgun lifting apparatus (7). 9 m; airgun total volume: 6000 cubic inch (4 airguns of 1500 cubic inch).…”

Section: Field Experimentalmentioning

confidence: 99%

See 1 more Smart Citation

A new way to generate seismic waves for continental crustal exploration

et al. 2007

View full text Add to dashboard Cite

An airgun experiment was conducted in a reservoir, with the total volume of the airgun array being 6000 cubic inch. The energy released by one excitation was estimated to be 6.68×10 6 J, which corresponded to a 3.4 kg TNT explosion. A 180 km long profile composed of 100 portable short period seismometers was deployed as a receiver system of the airgun signals. Two remarkable results can be drawn from the experiment: (1) the airgun explosion is harmless to the dam and the fish, and this kind of airguns can be regarded as a green and environmental protection seismic source on land; (2) seismic wave generated by this airgun source can be recorded by permanent stations with offset larger than 200 km. And the wave amplitudes recorded by nearby and remote stations are equivalent to the wave generated by 800 kg dynamite explosion. The airguns can be used as a light to illuminate the continental crustal structure of an area of about 100000 km 2 .airgun, reservoir experiment, green and environmental protection seismic source Earthquakes shed light on illuminating the Earth interior [1] . To achieve long offset seismic survey, it is common to use large explosions as seismic sources for continental crustal exploration. For example, explosives in the order of one ton are usually used in the seismic surveys for 100-300 km offset distance. In the areas of poor excitation conditions, the amount of explosives may be increased further. Such way of explosions has a number of drawbacks: 1) high expense, 2) environmental destruction, and 3) low repeatability, so it is hard to apply modern information processing techniques such as the seismic source stacking. With the rapid increase of urban population and economic development, it becomes more and more difficult to utilize large amount of explosives in seismic surveys.If the signals of a low power source can be detected in far distances, during the exploring of underground structure and status seismic waves [2] , a new technical platform will be established for deep structure investigations in geosciences [3][4][5] . This platform has significant potential applications in resource exploration, earthquake disaster reduction and urban geophysics.

show abstract

Section: Effect Of Airgun Shooting On the Fish In The Reservoirmentioning

confidence: 97%

Section: Field Experimentalmentioning

confidence: 99%

A new way to generate seismic waves for continental crustal exploration

et al. 2007

View full text Add to dashboard Cite

show abstract

“…Most reviews on the effects of airgun array pulses on marine life have accepted the assumption that airgun noise is limited to low frequencies, and have concentrated on species thought to have good low-frequency hearing (Caldwell, 2002;Popper et al, 2004;. We found that animals located near the surface when surfaceducting conditions are present may be exposed to measurable levels of airgun sound above 500 Hz.…”

Section: Discussionmentioning

confidence: 75%

Echolocation-based foraging by harbor porpoises and sperm whales, including effects of noise and acoustic propagation

DeRuiter¹

2008

View full text Add to dashboard Cite

In this thesis, I provide quantitative descriptions of toothed whale echolocation and foraging behavior, including assessment of the effects of noise on foraging behavior and the potential influence of ocean acoustic propagation conditions on biosonar detection ranges and whale noise exposure. In addition to presenting some novel basic science findings, the case studies presented in this thesis have implications for future work and for management.In Chapter 2, I describe the application of a modified version of the Dtag to studies of harbor porpoise echolocation behavior. The study results indicate how porpoises vary the rate and level of their echolocation clicks during prey capture events; detail the differences in echolocation behavior between different animals and in response to differences in prey fish; and show that, unlike bats, porpoises continue their echolocation buzz after the moment of prey capture.Chapters 3-4 provide case studies that emphasize the importance of applying realistic models of ocean acoustic propagation in marine mammal studies. These chapters illustrate that, although using geometric spreading approximations to predict communication/target detection ranges or noise exposure levels is appropriate in some cases, it can result in large errors in other cases, particularly in situations where refraction in the water column or multi-path acoustic propagation are significant.Finally, in Chapter 5, I describe two methods for statistical analysis of whale behavior data, the rotation test and a semi-Markov chain model. I apply those methods to test for changes in sperm whale foraging behavior in response to airgun noise exposure. Test results indicate that, despite the low-level exposures experienced by the whales in the study, some (but not all) of them reduced their buzz production rates and altered other foraging behavior parameters in response to the airgun exposure. Sincere thanks also to the many other people who have helped with data collection and analysis over the course of my graduate work, and also to everyone who offered comments on drafts of this thesis. More detailed acknowledgments can be found at the end of each chapter, but here I would especially like to thank the following. Thesis Objectives and Chapter 1 OverviewThe goal of my thesis research has been to provide quantitative descriptions of toothed whale echolocation and foraging behavior (Chapters 2 and 5), including assessment of the effects of noise on foraging behavior (Chapter 5) and the potential influence of ocean acoustic propagation conditions on biosonar detection ranges (Chapter 3) and whale noise exposure (Chapter 4). I have focused on two study species, the harbor porpoise (Phocoena phocoena, Chapters 2-3) and the sperm whale (Physeter macrocephalus, Chapters 4-5).The following sections present background information relevant to the research presented in the rest of the thesis, beginning with a review of previous research on the use of echolocation by foraging animals. This review is followed by b...

show abstract

“…The impact of the seismic sources on the fish and marine mammals is one of the major concerns in marine geophysical exploration. In the last two decades, many studies have been conducted on the effect of airgun sources on marine wildlife (McDonald et al 1993; Caldwell and Dragoset 2000; Caldwell 2002; Nieukirk et al 2004; DeRuiter et al 2006; Madsen et al 2006). As of now, this discussion has not reached a definitive conclusion but what is known is that observations are still needed.…”

Section: Methodsmentioning

confidence: 99%

Using an airgun array in a land reservoir as the seismic source for seismotectonic studies in northern China: experiments and preliminary results

Chen

Liu

et al. 2008

Geophysical Prospecting

View full text Add to dashboard Cite

A B S T R A C TThis paper reports the field setup and preliminary results of experiments utilizing an airgun array in a reservoir in north China for a seismotectonic study. Commonly used in offshore petroleum resource exploration, the airgun source was found to be more useful than a traditional explosive source for large-scale and long offset land seismic surveys. The airgun array, formed by four 1,500 in 3 airguns (a total of 6,000 in 3 in volume) was placed at a depth of 6-9 m into the reservoir to generate the pressure impulse. No direct evidence was found that the airgun source adversely affected the fish in the reservoir. The peak ground acceleration recorded on the top of the reservoir dam 100 m away was 17.8 gal in the horizontal direction; this is much less than the designed earthquake-resistance threshold of 125 gal for this dam. The energy for one shot of this airgun array is about 6.68 MJ, equivalent to firing a 1.7 kg explosive. The seismic waves generated by the airgun source were recorded by receivers of the regional seismic networks and a temporary wide-angle reflection and refraction profile formed by 100 short-period seismometers with the maximum source-receiver offset of 206 km. The seismic wave signature at these long-offset stations is equivalent to that generated by a traditional blast source in a borehole with a 1,000-2,000 kg explosive. Preliminary results showed clear seismic phases from refractions from the multi-layer crustal structures in the north China region. Forward modelling using numerical simulation confirms that the seismic arrivals are indeed from lower crustal interfaces. The airgun source is efficient, economical, environmentally friendly and suitable for being used in urbanized areas. It has many advantages over an explosive source for seismotectonic studies such as the high repeatability that is supreme for stacking to improve signal qualities. The disadvantage is that the source is limited to existing lakes or reservoirs, which may restrict experimental geometry. I N T R O D U C T I O NIn earthquake hazard mitigation studies, seismologists are responsible for providing the general public and the earthquake engineering community with a high-resolution crustal model as the basis for designing earthquake-resistant infrastructures. *

show abstract

Does air-gun noise harm marine mammals?

Cited by 8 publications

References 0 publications

A new way to generate seismic waves for continental crustal exploration

A new way to generate seismic waves for continental crustal exploration

Echolocation-based foraging by harbor porpoises and sperm whales, including effects of noise and acoustic propagation

Using an airgun array in a land reservoir as the seismic source for seismotectonic studies in northern China: experiments and preliminary results

Contact Info

Product

Resources

About