Abstract: Apparatus for detection and analysis of secondary uranium ores to provide signature indication of type by ultraviolet induced fluorescence and detection of fluorescence excitation time, peak value and decay time. The apparatus employs laser irradiation of selected terrain and telescopic detection at specific light wavelengths, viz. the yellow to green band; and thereafter detected signals are processed with specific circuitry to obtain and provide readout of the signature parameters.

Abstract: A spectral natural gamma radiation logging tool is calibrated with a material of known potassium content so that the natural gamma radiation measured by such logging tool is related to potassium concentration. The earth formations surrounding a borehole are logged with such logging tool to identify the presence of potassium. A specified concentration of potassium correlates inversely with a magnetic mineral content in the earth formation. The amount of magnetic mineral content is a measure of the presence of the non-magnetic mineral platinum in the earth formation.

Abstract: The present invention provides probe equipment for mounting on an underground mining machine in order to receive radiation from strata adjacent to the mining machine, the probe equipment comprising a housing having screening shields defining the boundaries of a window for allowing passage into the housing of radiation from said strata, the radiation being received by sensing means mounted within the housing. Radiation barrier means interrupt at least some of the radiation from the shale strata to effectively provide a degree of collimation to the path of the received radiation to thereby limit the field of vision of the sensing means to an acceptable extent.

Abstract: In order to achieve airborne exploration for minerals in which both color and size information is obtained from fluorescing targets, a pulsed ultraviolet source is directed downwardly from the aircraft to a target area, and light from any responsively fluorescing discrete target is passed through receiving optics which includes a plurality of choppers of different fineness. A multiply-chopped signal is passed through a light pipe which includes filters to separate the signal into a plurality of electronic channels according to the respective color components. Signals are further processed by division into a plurality of parallel paths according to chopper frequency and applied to a series of integrators which are specially configured to remove noise from several sources to markedly improve the signal to noise ratio. The data thus obtained is stored, along with time and position information, onto conventional digital recording means for subsequent retrieval and analysis.

Abstract: A moisture and density gauge which combines sources of gamma and neutron radiation in a casing which is placed in the medium being analyzed. The gauge includes detectors for the gamma and neutron radiation being placed in end to end configuration within the casing such that the neutron detector is placed between the gamma radiation detector and the source of gamma radiation.

Abstract: Method and apparatus for detecting the presence of hydrocarbons and other substance that fluoresces or absorbs light within a body of water which utilizes a controlled submersible vehicle scanning at or near the water bottom. The method utilizes a selected frequency light source as carried by the submersible to scan the water bottom, and the returned light energy, either at the wavelength of oil fluorescing in water or the source frequency backscatter, is detected and processed for the water bottom as well as a water region that is a selected distance above the water floor. Alternative forms of apparatus are disclosed for carrying out the functions of both oil fluorescence detection, and for obtaining differential absorption readings as to light source backscatter energy that is created by the ambient water and other factors in the water environment such as marine life, turbidity, etc.

Abstract: An apparatus for the detection of fluorescence. An airborne optical system carried in an aircraft or spaceship scans a sunlit swath of terrain over a field of view defined by a selected one of the fringe rings of a Fabry-Perot etalon designed to pass a selected Fraunhofer line. A first series of detectors are disposed to sense light intensity over a predetermined arc within said selected ring. A second like series of detectors are disposed to sense light intensity just outside said selected ring. Electronic means are connected to said first and second plurality of detectors for determining the fluorescence reflected from the swath of terrain.

Abstract: The invention relates to a method of measuring the concentration of radon and radon daughters in the ground, particularly at great depth and/or below the ground-water level. In accordance with the invention a detector is freely suspended from a wire and placed in a container intended for collecting gas rising up from the ground. The container is buried at a desired depth beneath the surface of the ground and the detector is exposed to the gas in the container over a given period of time. Subsequent to this exposure period, the detector is drawn up by means of the wire, together with a sleeve, protecting the detector from contact with surrounding ground, through the roof of the container and up through the ground, to a location so selected that the registered contents of radon and radon daughters can then be determined on the basis of the data registered on the detector. The invention also relates to preferred apparatus for carrying out the method.

Abstract: The present invention concerns a method for remotely surveying the earth's surface. The method comprises the steps of advancing a plurality of electromagnetic scanning devices (3) along a known path at a predetermined height and velocity above the earth's surface, simultaneously scanning a track (4) of predetermined width on the earth's surface with said scanning devices, detecting with the scanning devices electromagnetic radiation received from the earth's crust in the electromagnetic spectrum, each scanning device responding to a different spectral range within the electromagnetic spectrum, and producing a film record (20) from each scanning device corresponding to the intensity of the radiant energy detected by the scanning device within its spectral range.

Abstract: The invention relates to a method for detecting and measuring alpha-emitting substances, such as radon and/or daughter products of radon, by registering nuclear tracks on a detector. By conducting away during measuring any electrostatic field which may have built-up on the detector, there is eliminated the risk of erroneous information being obtained with respect to the dosage of radiation received.A device in the form of a dosimeter for carrying out the detecting and measuring method is also provided in accordance with the invention. Arranged on or in the immediate vicinity of the registering surface (1) of the detector is an electrically conductive material (2) which at least partially covers the registering surface. In a preferred embodiment, the dosimeter may include at least one absorber (4) arranged between the registering surface and the electrically conductive material.

Abstract: Method and apparatus for detecting the presence of hydrocarbons and other substance that fluoresces or absorbs light within a body of water which utilizes a controlled submersible vehicle scanning at or near the water bottom. The method utilizes a selected frequency light source as carried by the submersible to scan the water bottom, and the returned light energy, either at the wavelength of oil fluorescing in water or the source frequency backscatter, is detected and processed for the water bottom as well as a water region that is a selected distance above the water floor. Alternative forms of apparatus are disclosed for carrying out the functions of both oil fluorescence detection, and for obtaining differential absorption readings as to light source backscatter energy that is created by the ambient water and other factors in the water environmentsuch as marine life, turbidity, etc.

Abstract: A source of fast neutrons is pulsed to irradiate the formations surrounding a borehole with neutrons to produce inelastic neutron scattering in metallic materials located within the formations. Gamma-rays emitted from the formations in response to the inelastic neutron scattering from the metallic materials is detected as an indication of the presence of such materials within the formations.

Abstract: A method for ore prospecting comprises: locating the ore body, determining the concentration values of a selected chemical element at two positions in the ore body; measuring the distance between the two positions; estimating the freezing segregation behavior of the selected element during the freezing of the ore body; and from the determined concentration values, measured distance, and estimated freezing segregation behavior calculating the size of the ore body.

Abstract: A method of and apparatus for sorting pieces or particles of radioactive ore where the particles are moved one after another substantially horizontally then discharged into a gravity-accelerated trajectory which is substantially free-fall but can be controlled to follow a modified path by a low-friction slide plate. The falling particles pass a plurality of radiation detectors arranged in line along their path with increasing velocity due to gravity providing the required separation of the pieces so that each detector is subject to the radiations of essentially only one piece at a time. The size and number of detectors and the path length covered by the detectors is determined by the size of the pieces and the cut-off grade and accuracy required. All counts corresponding to a particular piece and derived successively from the plurality of detectors are accumulated since accuracy increases and percentage of probable error decreases with increased total count.

Abstract: We have discovered that certain photoluminescent minerals of zinc, fluorine, tungsten, molybdenum, mercury and other elements which may naturally occur at the surface of the earth can be selectively detected in the presence of most other photoluminescent minerals and organic materials which are likely to occur at the earth's surface. The basis of selective detection is the discovery that the lifetimes of photoluminescent emission of materials in the latter class are much shorter than the lifetimes of photoluminescent emission of materials in the former class. This invention utilizes this discovery in the detection of minerals of uranium, zinc, lead, fluorine, tungsten, molybdenum, mercury and other elements.

Abstract: A method for remote analysis of a mixture of materials where one of the components has thermal characteristics different from the other components. In a preferred embodiment, tar sands on a moving belt or dropping into a hopper are irradiated with infrared radiation and the radiant thermal flux of the heated tar sands is remotely detected and measured to determine bitumen content.

Abstract: A relatively small diameter, relatively deep hole is made in the ground and a sampler tube is inserted therein. An acetate sleeve is detachably inserted into a chamber on the upper end of the sampling tube and the sampler is left for at least sixteen hours and preferably longer in order to permit radon gas to migrate up the tube. Daughter products of radon deposit on the acetate film which is then placed in a scintillation cell attached to the counting chamber of a scintillation counter, which counts the alpha emissions of the daughter products thereby permitting the amount of radon gas to be calculated. This method reduces considerably any contamination of the scintillation counting chamber so that cleansing is not necessary thus permitting a much higher level of productivity. The system is also totally insensitive to thoron so that no correction for thoron signals is required.

Abstract: This invention relates to a novel method for both locating and evaluating subsurface uranium-bearing formations containing an apparent grade of up to approximately 5% of contained U.sub.3 O.sub.

Abstract: A means and method for distinguishing full energy absorption peaks from background energy in a gamma ray prospecting system. Photopeaks in the received energy spectrum are determined, and boundaries to the peaks are located. The energy within the boundaries assuming a predetermined curve between the boundaries is integrated. The filtered energy within the actual photopeak curve is also integrated, and the two integrated signals are subtracted to provide a signal representative of the net photopeak area or amplitude. This peak area (or amplitude) is directly proportional to intensity of gamma radiation due to uranium, thorium and potassium in the ground. This signal is displayed and continuously updated on a cathode ray tube as a function of time.

Abstract: The present invention discloses a method and apparatus of elemental analysis which finds particular application in the on-line analyses of the specific energy (calorific value) of coal or coke by the determination of carbon content. Analysis is achieved by a comparison of the output of neutron inelastic scatter which produces first .gamma. rays and of scatter of second .gamma. rays. Preferably 4.43 MeV carbon .gamma. rays are used and, in addition, one or more of moisture, ash, or hydrogen content of coal or coke can be measured using 2.2 MeV hydrogen capture .gamma. rays. The method and apparatus have the advantage of providing a compensated count rate that is essentially independent of sample compaction.

Abstract: A method of uranium exploration employs the detection of radon gas decay products to provide an indication of uranium mineralization. A plurality of collectors of similar surface areas are exposed to soil at or from spaced locations on an exploration site for a time sufficient for the decay products to deposit on the collectors and then, within substantially similar periods following the termination of the exposure, alpha particles, beta particles or gamma rays emitted from the collectors are measured and the measurements are compared. The collectors may be exposed to the soil in air spaces in or on the ground or in containers holding soil samples and may be electrically charged.

Abstract: The proportion of a radioactive material in a moving mass of material is determined with a sensor which derives an output signal proportional to the mass of radioactive material. The output signal is calibrated against known reference values to give a quantitative value of mass. The sensor includes a plurality of scintillation crystals. Problems associated with inhomogeneity of material distribution are overcome by averaging the sensed radiation over a time period.

Abstract: Gamma spectrum measurement signals received from a downhole instrument containing a scintillation counter are coupled into a multi-channel analyzer. The analyzer converts the received pulses to pulses in separate channels according to energy levels of the received measurements. The energy channels from the multi-channel analyzer are coupled to digital decoders which are set up for energy level windows for preselected elements and the total occurrence count. These outputs are coupled into a microprocessor stripper which includes storage buffers sized in accordance with the logging rate and crystal utilized in the scintillation counter. These storage registers permit filtering in addition to stripping the various energy channels of the influence radiation caused by the elements having and energy band centered around a higher energy level.

Abstract: The present invention contemplates a system for detecting an interface between a mineral seam and the surrounding earth formation utilizing a radiation source and a radiation receiver mounted on a miner having a positionable cutter assembly. As the miner is moved into the coal seam, a first distance is continuously sensed between one surface formed in the mineral seam by the miner cutter assembly and the surrounding earth formation and the miner cutter assembly is positioned in response to the sensed first distance. As the miner is withdrawn from the coal seam, a second distance is continuously sensed between one surface formed in the mineral seam by the miner cutter assembly and the surrounding earth formation and the miner cutter assembly is positioned in response to the sensed second distance.

Abstract: A high-energy laser (22) carried in an aircraft (10) directs a laser beam (16) downward to a point (18) on the earth's surface beneath the aircraft (10). The intensity of the laser beam (16) is such that the material at the point (18) of contact is vaporized and thereby caused to emit atomic emission spectra characteristic of the material. A spectrometer (28) carried in the aircraft (10) collects the resulting spectra which is analyzed to determine the type and quantity of chemical elements present in the vaporzied sample. The laser beam (16) is directed at the point (18) on the surface with sufficient energy and for a period of time so as to penetrate the surface layer and vaporize the underlying material more representative of the overall mineral composition present in the region of the sample. A second laser beam from laser (29) is directed to the point (18) of contact to generate radiation for Raman and fluorescence spectrometry.

Abstract: A thin film radiation dosimeter is secured to a plate member exhibiting sufficient mechanical strength to function as a dosimeter support member and electrical resistance characteristics which permit the plate member to function as a heating element during the readout process of the radiation dosimeter.

Abstract: A method for the detection and identification of uranium bearing materials in media found in nature such as rocks, soils, surface and sub-surface waters, vegetation, or in material which has been subjected to physical or chemical processing comprises the steps of: irradiating the media with a light, having a single wavelength or narrow band of wavelengths in the range of about 2400 to 5000A for a time equal to or less than about 100 microseconds; waiting for a period of time, which is dependent on twice the distance of the light-source to the irradiated medium, followed by measurement of the intensity and decay time of the luminescent light emitted by the irradiated media in a narrow spectral range, having a wavelength greater than the wavelength of the light used to irradiate the media.

Abstract: In a radiation dosimeter assembly consisting of a wafer-like radiation dosimeter in combination with a mechanical support member the radiation dosimeter is secured within an aperture of the support member by disposing a protective film on either side of the dosimeter and securing the film to the support member via a high temperature adhesive or high temperature adhesive film. This assembly technique permits the annealing of the combination of the dosimeter and the support member to a temperature of about 300.degree. C. which is the typical process for "erasing" extraneous radiation dosage stored in the dosimeter prior to the use of the radiation dosimeter/support combination for radiation measurements. The capability of annealing the total combination permits stock piling of preassembled radiation dosimeter/support member combinations for extended periods of time.

Abstract: A device for detecting fissionable material such as uranium in low concentrations by interrogating with photoneutrons at energy levels below 500 keV, and typically about 26 keV. Induced fast neutrons having energies above 500 keV by the interrogated fissionable material are detected by a liquid scintillator or recoil proportional counter which is sensitive to the induced fast neutrons. Since the induced fast neutrons are proportional to the concentration of fissionable material, detection of induced fast neutrons indicate concentration of the fissionable material.

Abstract: A method of and apparatus for sorting pieces or particles of radioactive ore where the particles are moved through the apparatus in an asynchronous or non-constant manner. The particles are moved one at a time to a position in front of a radiation detector where they are temporarily stopped. The counts from the particle are accumulated with respect to time. In a control unit of the apparatus there is data representing a cut-off grade radiation rate and early upper and lower decision limits are established with regard to the cut-off rate. As soon as the accumulated count/time ratio from the detector exceeds the upper limmit or falls below the lower limit, the control unit is able to provide a decision to accept or reject the particle. If the particles are not closely sized then the size of each particle is determined before it is positioned in front of the radiation detector and the size determination is used to modify the cut-off grade and upper and lower early decision limits.

Abstract: Alpha particles emitted from radon 220, a daughter product formed from the decay of thorium, are prevented from reaching an alpha particle detector by enclosing the detector in a volume into which alpha-emitting radioactive gases can only enter through a semipermeable membrane at least about 10 mg/cm.sup.2 in thickness. The enclosed volume must be between 30 and 2000 cm.sup.3 and the (AP)/(VL) ratio must be between 10.sup.-7 and 10.sup.-5. Also, the detector must be positioned so as to expose it to gas from the membrane for a distance of at least 2 cm through a solid angle of at least one steradian.

Abstract: An improved thermoluminescent dosimeter system and apparatus for sensing alpha particle emission. A thermoluminescent body is sealed between a pair of metallized plastic films. The dosimeter is mounted within a protective inverted cup or a tube closed at one end, which is disposed in a test hole for exposure to radioactive radon gas which is indicative of uranium deposits.

Abstract: An onboard power supply and metering unit is connected, via an overboard cable e.g., 1000 meters long, to an underwater light-pulse projecting unit and a fluoroescence-sensing receiver unit. The operating power is transmitted to the underwater units by an onboard constant-current source, instead of a voltage source. Likewise, the output signal of the receiver unit is transmitted through the cable in the form of a current, not a voltage. The current of the receiver's photodiode is integrated, the peak value of the integral determined and held, this held value logarithmized, the logarithmized value sampled and held, and the held voltage converted to a current constituting the output signal. The offset of the peak detector and the input stage of the log amplifier are balanced automatically, by a balancing signal applied during pulse measurements, but derived between pulse measurements.

Abstract: A reference cell simulating the light amplitude spectrum of an alpha scintillation cell containing radon.sup.222. The cell includes a gas-tight container having a transparent window. The interior of the container, aside from the window, has a coating of a luminescent material. Inside of the container lies an amount of radium.sup.226. The radium radioactively decays to produce alpha particles and radon.sup.222. The radon.sup.222 and its daughter particles also undergo radioactive decay to produce further alpha particles. The 1620-year half life of the radium.sup.226 assures an adequate supply of the radon.sup.222 for a greater time period than radon's 3.825-day half life. The production rate of the alpha particles within the container increases for a period of approximately 22 years after the cell's construction. Although the radium.sup.226 generally has a nonuniform distribution in the cell, the produced radon assumes a gaseous form and uniformly diffuses throughout the entire cell.

Abstract: A coal-rock interface detector employing a radioactive source and radiation sensor wherein the source and sensor are separately and independently suspended and positioned against a mine surface of hydraulic pistons which are biased from an air cushioned source of pressurized hydraulic fluid.

Abstract: Underground uranium deposits are located by placing wires of dosimeters each about 5 to 18 mg/cm.sup.2 thick underground in a grid pattern. Each dosimeter contains a phosphor which is capable of storing the energy of alpha particles. In each pair one dosimeter is shielded from alpha particles with more than 18 mg/cm.sup.2 thick opaque material but not gamma and beta rays and the other dosimeter is shielded with less than 1 mg/cm.sup.2 thick opaque material to exclude dust. After a period underground the dosimeters are heated which releases the stored energy as light. The amount of light produced from the heavily shielded dosimeter is subtracted from the amount of light produced from the thinly shielded dosimeter to give an indication of the location and quantity of uranium underground.

Abstract: A radiation scanning-detecting and processing system having a composite detector arrangement including detector elements having mutually different sensitive areas. An information processing system coupled to such detector arrangement is effective in response to certain operational parameters to selectively vary the relative contributions of detector elements having different sensitive areas to the overall signal derived from all detector elements in combination.

Abstract: A measuring device to be conveyed through an oil or gas pipeline at the bottom of the sea is provided for measuring the radioactivity of the surroundings along the pipeline. Thus, the support and/or the covering of the pipeline may be tested, the sea bottom sediments having an appreciably higher gamma radiation source strength than the sea water and the oil or gas which flow through the pipeline.

Abstract: In the proposed method a solid specimen is cleaved to obtain a pair of conjugate cleavage surfaces. Then, a scanning electron microscope is used to obtain images of the conjugate surfaces at a predetermined magnification. The images are superimposed to produce an image of a porous component of the solid structure. Thereafter, the image of the porous component is superimposed on each image of the conjugate surfaces to obtain a pair of images of imprints of solid grains. The image of pores and grain imprints is then converted to a contour form, all converted images are superimposed, and a contour image of the entire structure of the solid is obtained. The images of pores, grain imprints and complete structure of the solid are quantitatively analyzed with the aid of image analyzers, digitized and fed into a computer for calculation of the solid properties of interest, e.g., perviousness, using an appropriate program.

Abstract: An apparatus for determining the depth of a radiation source within a body of material utilizing a radiation source holder moving the radiation source within the body. A plurality of switches have contacts that are fixed in relation to the movement of the radiation source within the material. Trigger means activates a particular switch at a preselected depth of the radiation source. Means for indicating the activation of a switch would thus produce a signal as a representative of the depth of the radiation source.

Abstract: A method and apparatus are described for determining the occurrence or non-occurrence of subsurface air flow and, in the event of the occurrence of subsurface air flow, being able to determine its direction into or out of the earth. The determinations are accomplished by the use of a pair of alpha particle detectors, each of which is disposed in a protective enclosure to constitute a detector unit. A pair of such units is employed, the two units being buried in the earth spaced from each other and at different depths. Readings detecting alpha particle emission are taken on both units and compared.

Abstract: A method is provided for determining the shale content of mined coal by monitoring the thorium content of the coal. Thorium content and ash content are shown to be related whereby a direct reading of the thorium will be indicative of the shale content of the coal and the ash content of the coal. The method utilizes the natural radiation of thorium to provide the continuous or selective control of mined coals.

Abstract: A method for determining the distance from a given point in a coal seam to shale by sensing the thorium radiation from shale layers positioned about the coal seam. The invention is useful for maintaining a drill in a desired position in a coal seam and guiding the drill in response to the sensed radiation.

Abstract: Presence of metals such as copper and nickel being economically interesting etals are determined as to existence thereof in the content of manganese nodules according to a method by means of analysis of the activation gamma spectrum of manganese nodule samples after a neutron irradiation thereon. The sample is irradiated with fast neutrons and from the resulting gamma spectrum the ratio of radiation intensities of two main component parts preferably manganese and iron is taken in order to determine the percentage metal content by way of empirically obtained geochemical correlation-data which reproduce the percentage parts of further elements dependent upon proportional ratio of two main elements of the manganese lumps.

Abstract: A technique for the in situ evaluation of the organic carbon content of earth formations penetrated by a well borehole is disclosed. The energy spectrum of natural gamma radiation occurring in earth formations penetrated by a well borehole is observed in energy regions corresponding to uranium, potassium and thorium. Quantitative evaluations of the relative abundances of these elements are made by comparing the observed spectra with standard gamma ray spectra. The relative abundances of these elements may then be interpreted in terms of the organic carbon content of earth formations by comparison with predetermined relationships found to exist therebetween.

Abstract: A borehole logging tool employs two neutron sources of differing energy outputs, two gamma-ray detectors, and a neutron detector in the radioactivity logging of a coal-bearing formation. A first of the gamma-ray detectors measures the gamma rays produced by the formation in response to the higher energy neutron source. A second of the gamma-ray detectors measures the gamma rays produced by the formation in response to the lower energy neutron source. The neutron detector measures thermal or epithermal neutrons produced by the formation in response to the neutron sources. These measurements are selectively transferred to a recording system employing a plurality of energy level discriminators, count rate meters, and comparators. The recording system, in response to these measurements, provides output signals representative of the carbon, sulfur, ash, and neutron moderating power of the coal in the formation being logged.

Abstract: Valuable information on the presence or absence of uranium-enriched ores, geothermal reservoirs, or natural gas sources is obtained by analyzing earth samples for their relative Po210 content.

Abstract: A method and apparatus are described for reducing or removing the background noise caused by thoron gas (.sup.220 Rn) in uranium exploration conducted by the detection of radon gas (.sup.222 Rn) emanating from the ground. This is accomplished by the use of a number of alpha particle detectors, each of which is disposed in a protective enclosure. A permselective membrane, which permits, but selectively retards, the passage therethrough of gases is disposed in the path to be traversed before such gases can reach the alpha particle detector. The retarding influence of the membrane should be sufficient to make the concentration of thoron inside the enclosure small relative to the concentration of thoron outside the enclosure. The influence of the membrane on radon should be negligible, i.e. the randon concentration inside and outside the enclosure should be substantially equal.

Abstract: A method and apparatus are described for reducing or removing the background noise caused by thoron gas (.sup.220 Rn) in uranium exploration conducted by the detection of radon gas (.sup.222 Rn) emanating from the ground. This is accomplished by the use of a number of alpha particle detectors, each of which is disposed in a protective enclosure. A barrier which permits, but deliberately retards, the passage therethrough of gases is disposed in the path to be traversed before such gases can reach the alpha particle detector. The increase in the transit time made necessary by requiring soil gases to move through the barrier should be sufficiently long to allow the decay of most of the thoron, thereby eliminating its contribution to the total signal reflected at the detector.

Abstract: In the method of separating isotopes wherein a desired isotope species is selectively deflected out of a beam of mixed isotopes by irradiating the beam with a directed beam of light of narrowly defined frequency which is selectively absorbed by the desired species, the improvement comprising irradiating the deflected beam with light from other light sources whose frequencies are selected to cause the depopulation of any metastable excited states.