Seismic explosives

Principal applications of Detasheet expls include field demolition, underwater explosions, seismic prospecting and metal cutting and hardening. For example, manganese (Hadfield) steel can be hardened by inducing a shock wave in the metal thru detonation of Detasheet placed direcdy on the metal s surface (Ref 5, p 5)... 

Seismocord = detonating cord for seismic shoths (german) 280 seismic explosives seismic gelatins 279... 

Overload Impact (vehicle, ship) Flooding, ice floes, floating timber Fire Explosion Seismic activity Wind action... 

An aluminum housing containing an automatic oscillograph was mounted below the balloon. The ircMi ballast and the external geophone for recording man-made explosive seismic signals were located rai the ocean bottom (Ewing et al. 1946). 

Workers conduct seismic explosions in search of oil and gas deposits on prh ate islands in Bob I /iarshall Wilderness ea, / ontana. (Corbis Corporation)... 

HNS/Teflon Explosive Charges For The Apollo 17 Seismic Experiment, LSPE , NOLTR 73-44... 

Figure 14.10 illustrates the method of seismic prospecting on land by what is known as reflection shooting. A hole usually 10 to 12 cm in diameter is drilled to a depth of 15 to 30 m. The charge of explosive is likely to be 5 to 12-5 kg and the stemming used is usually water. As the explosive must fire under a depth of water which may exceed 45 m, special varieties of gelatines are employed (see p. 53). Alternatively, a powder explosive can be sealed into pressure-resistant metal containers. Special detonators are also employed, not only to withstand the possible head of water, but also to have a specially short bursting time (see p. 113). 

Seismic techniques, the reflection and refraction of sound or shock waves propagated through the earth, are also used to reveal details of the structure and interrelationship of various layers in the subsurface. The shock or sound waves record densities in the earth s surface that may indicate an oil or gas reservoir. Explosive charges or vibration devices are used to impart the required shock wave. 

Hexanitrostilbene or HNS (C14H6N6012) is a heat-resistant yellow crystalline solid explosive. HNS is also resistant to radiation, insensitive to electric sparks, and less sensitive to impact than tetryl. It is used in heat-resistant booster explosives and has been used in stage separations in space rockets and for seismic experiments on the moon. Its melting temperature is 316 °C.12... 

Plutonium is the most important transuranium element. Its two isotopes Pu-238 and Pu-239 have the widest applications among all plutonium isotopes. Plutonium-239 is the fuel for nuclear weapons. The detonation power of 1 kg of plutonium-239 is about 20,000 tons of chemical explosive. The critical mass for its fission is only a few pounds for a solid block depending on the shape of the mass and its proximity to neutron absorbing or reflecting substances. This critical mass is much lower for plutonium in aqueous solution. Also, it is used in nuclear power reactors to generate electricity. The energy output of 1 kg of plutonium is about 22 million kilowatt hours. Plutonium-238 has been used to generate power to run seismic and other lunar surface equipment. It also is used in radionuclide batteries for pacemakers and in various thermoelectric devices. 

Addnl Refs A) Collective, "Air Burst in Blast Bombs . A Compilation of Papers Presented at NDRC Div 2 Symposium, OSRD 4923 (1945) B) Collective, "Underground Explosion Test Program , Final Rept, Vol II, "Rock , Engineering Research Associates, Division of Remington Rand Inc, 30 April 1953 (Conf) (Not used as a source of information) C) G.R. Pickett, "Seismic Wave Propagation and Pressure Measurements Near Explosions , Quarterly of the Colorado School of Mines 50(4) (Oct 1955) D) W.E. Deal, "Shock Hugoniot in Air , JApplPhys 28, 782-84(1957) E) Dunkle s Syllabus, Session 26, 23 Apr 1958, pp 313-18 F) Dunkle s Syllabus, Suppl to Section 26 (1961) G) Dunkle, private communication,... 

Vibrocol, long length (ca 65 ft or more), pre-packaged columnar charges of explosives were especially suited for some land seismic exploration. Low-priced, packaged blasting agents, Dynatex and Tritex were useful in wet locations where ANFO could not be used... 

SuperSeis a patented explosive system for offshore seismic exploration, jointly developed. by Hercules and Western Geophysical Company, became operational in 1971. It consists of small explosive charges that are ejected from the exploration boat via a long pressured tube and detonate after an appropriate delay, at... 

Seismograph-Grade Explosives for use in seismic prospecting on land and offshore. Various grades are available in diameters from 2 to 8 inches packaged in fiber cartridges, metal cans, or plastic ... 

Tutamite. One of the Italian Esplosivi per prospezioni geosismiche (Explosives for Geo-seismic Prospecting) is listed by Belgrano (Ref 31, p 334) together with other Italian seismic expls Sismite and Geo-Mon A, without giving their compositions... 

Nowadays, oil is considered to be the most important resource affecting the economy of many countries. For oil exploration, it is necessary to fix the location of actual oil bearing strata after drilling of exploratory holes. There are three segments in this industry where explosives are used extensively (i) seismic exploration, (ii) well perforation and (iii) abandonment... 

Introduction of Conjugation The best example of imparting higher thermal stability through the introduction of conjugation in explosive molecules is hexanitrostilbene (HNS), synthesized by Shipp [58, 59] of the US Naval Ordnance Laboratory (NOL) in 1964. Plants for full-scale production exist in the UK and China, based on the method of Shipp [60]. It has proved its efficiency as a heat-resistant explosive as well as a component of heat-resistant formulations employed in the Apollo spaceship and for seismic experiments on the moon [61]. HNS has also been reported for use in achieving stage separation in space rockets. 

The literature suggests that thermally stable explosives such as HNS were employed for seismic experiments on the moon [61]. This is probably due to safety considerations while handling explosives for such applications on the lunar surface. 

In supersonic missiles where warheads are subjected to aerodynamic heating, conventional explosives cannot be used and thermally stable explosives like TATB, TACOT, HNS and PYX, etc. are necessary for such systems. Some formulations based on these explosives are HNS/Kel-F800 95/5 (developed by Atomic Weapons Research Establishment, Aldermaston, UK) and AFX 521 (PYX/Kel-F800 95/5 — developed by Los Alamos National Laboratory, USA). Their shock sensitivities lie in the region required for boosters. HNS/Teflon explosive charges have also been used for the Apollo 17 seismic experiments [199]. 

Kilmer, E.E. (1973) HNS/teflon explosive charges for the Apollo 17 seismic experiments. LSPE, Naval Ordnance Laboratory TR No.73-44. 

DuPont s Pyrocore. See Ref 7, p9 DuPont s Seismic Prospecting Explosives, such as Seismograph 60% High Velocity" Gelatin Nitramons WW, WW-EL, S Sc S-EL Seismogel A Seismex and Seismex PW (Ref... 

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