Abstract: A method for detecting hydrocarbons is described. The method includes performing a remote sensing survey of a survey location to identify a target location. Then, an underwater vehicle (UV) is deployed into a body of water and directed to the target location. The UV collects measurement data within the body of water at the target location, which is then analyzed to determine whether hydrocarbons are present at the target location.

Abstract: A method for detecting hydrocarbons with an underwater vehicle equipped with one or more measurement components is described. The method includes navigating the UV within the body of water; monitoring the body of water with measurement components associated with the UV to collect measurement data. The collected data from the UV is used to determine whether hydrocarbons are present and at the location.

Abstract: The present techniques are directed to a method for microprobe analyses of isotope ratios in inhomogeneous matrices. The method includes selecting matrix standards that have matrices that resemble a target matrix. A bulk isotope analysis is run on each of the matrix standards to determine a bulk isotope ratio value. A microprobe analysis is run on each of the matrix standards to determine a microprobe isotope ratio values for each of the plurality of matrix standards. Spurious values are eliminated from the microprobe isotope ratio values. The microprobe isotope ratio values are averaged for each of the matrix standards to create an average microprobe isotope ratio value associated with each of the matrix standards. The bulk isotope ratio value for each of matrix standards is plotted against the average microprobe isotope ratio value associated with each of the matrix standards to create a matrix corrected calibration curve.

Abstract: Systems and methods which provide electromagnetic subsurface mapping to derive information with respect to subsurface features whose sizes are near to or below the resolution of electromagnetic data characterizing the subsurface are shown. Embodiments operate to identify a region of interest (203) in a resistivity image generated (202) using electromagnetic data (201). One or more scenarios may be identified for the areas of interest, wherein the various scenarios comprise representations of features whose sizes are near to or below the resolution of the electromagnetic data (204). According to embodiments, the scenarios are evaluated (205), such as using forward or inverse modeling, to determine each scenarios' fit to the available data and further to determine their geologic reasonableness (206). Resulting scenarios may be utilized in a number of ways, such as to be substituted in a resistivity image for a corresponding region of anomalous resistivity for enhancing the resistivity image (207).

Abstract: A method for detecting hydrocarbons with an underwater vehicle equipped with one or more measurement components is described. The method includes navigating the UV within the body of water; monitoring the body of water with measurement components associated with the UV to collect measurement data. The collected data from the UV is used to determine whether hydrocarbons are present and at the location.

Abstract: A method for detecting hydrocarbons is described. The method includes performing a remote sensing survey of a survey location to identify a target location. Then, an underwater vehicle (UV) is deployed into a body of water and directed to the target location. The UV collects measurement data within the body of water at the target location, which is then analyzed to determine whether hydrocarbons are present at the target location.

Abstract: Method for assessing hydrocarbon source rock potential of a subsurface region without well log information. The method uses surface electromagnetic (121) and seismic (122) survey data to obtain vertical profiles of resistivity and velocity (123), which are then analyzed in the same way as well log data are analyzed by the well known Delta Log R method (124).

Abstract: Method for determining time-dependent changes [73] in the earth vertical and horizontal electrical resistivity and fluid saturations from offshore electromagnetic survey measurements. The method requires both online and offline data, which should include at least one electromagnetic field component sensitive at least predominantly to vertical resistivity and another component sensitive at least predominately to horizontal resistivity [62]. Using a horizontal electric dipole source, online Ez and offline Hz measurements are preferred. For a horizontal magnetic dipole source, online H2 and offline E2 data are preferred. Magnetotelluric data may be substituted for controlled source data sensitive at least predominantly to horizontal resistivity. Maxwell's equations are solved by forward modeling [64,65] or by inversion [66,67], using resistivity models of the subsurface that are either isotropic contrast, and [64,66] or anisotropic [65,67].

Abstract: Methods for detecting a liquid under a surface and characterizing Ice are provided The liquid may be a liquid hydrocarbon such as crude oil or fuel oil or mineral oil The surface may be ice, snow, or water, and the method may be practiced in an arctic region to detect oil spills, leaks, or seepages The methods may be used with a range finder to characterize marine ice The methods may include a nuclear magnetic resonance (NMR) tool with antenna to send a radio-frequency (RF) excitation pulse or signal into volume of substances being detected, detect an NMR response signal to determine the presence of the liquid of interest The NMR response may include a relaxation time element and an intensity level and may include a free induction signal (T2*), a spin echo signal (T2), a train of spin echo signals (T2), or a thermal equilibrium signal (T 1).

Abstract: The present techniques are directed to a method for microprobe analyses of isotope ratios in inhomogeneous matrices. The method includes selecting matrix standards that have matrices that resemble a target matrix. A bulk isotope analysis is run on each of the matrix standards to determine a bulk isotope ratio value. A microprobe analysis is run on each of the matrix standards to determine a microprobe isotope ratio values for each of the plurality of matrix standards. Spurious values are eliminated from the microprobe isotope ratio values. The microprobe isotope ratio values are averaged for each of the matrix standards to create an average microprobe isotope ratio value associated with each of the matrix standards. The bulk isotope ratio value for each of matrix standards is plotted against the average microprobe isotope ratio value associated with each of the matrix standards to create a matrix corrected calibration curve.

Abstract: Method for reducing air wave and/or magnetotelluric noise in controlled source electromagnetic surveying by either shielding the source (61) from the air interface, shielding the receivers from downward traveling electromagnetic energy, or by employing a second source (62) to preferentially cancel the air wave (and MT) part of the signal, or a combination of the preceding.

Abstract: This invention relates generally to a method of simulating the signal of an electromagnetic source using one or more dipole sources. In the method a dipole source is located at an excitation location corresponding to a segment of the electromagnetic source to be simulated. The dipole source is activated, and an electromagnetic signal recorded at one or more receiver locations. This process is repeated for additional excitation locations corresponding to additional segments of the electromagnetic source. The data from the sequence of dipole source excitation locations is processed to determine the simulated signal of the electromagnetic source.

Abstract: Method for generating a three-dimensional resistivity data volume for a subsurface region from an initial resistivity model and measured electromagnetic field data from an electromagnetic survey of the region, where the initial resistivity model is preferably obtained by performing multiple ID inversions of the measured data [100]. The resulting resistivity depth profiles are then registered at proper 3D positions [102]. The 3D electromagnetic response is simulated [106] assuming the resistivity structure is given by the initial resistivity model. The measured electromagnetic field data volume is scaled by the simulated results [108] and the ratios are registered at proper 3D positions [110] producing a ratio data volume [112]. A 3D resistivity volume is then generated by multiplying the initial resistivity volume by the ratio data volume (or some function of it), location-by location [114]. A related method emphasizes deeper resistive anomalies over masking effects of shallow anomalies.

Abstract: Methods for detecting a liquid under a surface and characterizing Ice are provided The liquid may be a liquid hydrocarbon such as crude oil or fuel oil or mineral oil The surface may be ice, snow, or water, and the method may be practiced in an arctic region to detect oil spills, leaks, or seepages The methods may be used with a range finder to characterize marine ice The methods may include a nuclear magnetic resonance (NMR) tool with antenna to send a radio-frequency (RF) excitation pulse or signal into volume of substances being detected, detect an NMR response signal to determine the presence of the liquid of interest The NMR response may include a relaxation time element and an intensity level and may include a free induction signal (T2*), a spin echo signal (T2), a train of spin echo signals (T2), or a thermal equilibrium signal (T 1).

Abstract: Systems and methods which provide electromagnetic subsurface mapping to derive information with respect to subsurface features whose sizes are near to or below the resolution of electromagnetic data characterizing the subsurface are shown. Embodiments operate to identify a region of interest (203) in a resistivity image generated (202) using electromagnetic data (201). One or more scenarios may be identified for the areas of interest, wherein the various scenarios comprise representations of features whose sizes are near to or below the resolution of the electromagnetic data (204). According to embodiments, the scenarios are evaluated (205), such as using forward or inverse modeling, to determine each scenarios' fit to the available data and further to determine their geologic reasonableness (206). Resulting scenarios may be utilized in a number of ways, such as to be substituted in a resistivity image for a corresponding region of anomalous resistivity for enhancing the resistivity image (207).

Abstract: Method for assessing hydrocarbon source rock potential of a subsurface region without well log information. The method uses surface electromagnetic (121) and seismic (122) survey data to obtain vertical profiles of resistivity and velocity (123), which are then analyzed in the same way as well log data are analyzed by the well known DeltaLogR method (124).

Abstract: Method for conducting an efficient and interpretable controlled-source electromagnetic reconnaissance survey for buried hydrocarbons. While a part of the survey area is being set up for measurement and data are being acquired, data from a nearby part of the survey area, surveyed just previously, are being rapidly processed and analyzed. If the analysis shows resistive anomalies of interest in a portion of a survey area, a fine-grid survey is quickly designed for that portion, and that survey is conducted next before moving source and receivers to a more distant part of the survey area.

Abstract: A method is disclosed for determining earth vertical electrical anisotropy from offshore electromagnetic survey measurements. The method requires both online and offline data, which includes at least one electromagnetic field component sensitive at least predominantly to vertical resistivity and another component sensitive at least predominantly to horizontal resistivity. Using a horizontal electric dipole source, online EZ and offline HZ measurements are preferred. For a horizontal magnetic dipole source, online HZ and offline EZ data are preferred. magnetotelluric data may be substituted for controlled source data sensitive to horizontal resistivity. Maxwell's equations are solved by forward modeling or by inversion, using resistivity models of the subsurface that are either isotropic or anisotropic.

Abstract: Method for generating a three-dimensional resistivity data volume for a subsurface region from an initial resistivity model and measured electromagnetic field data from an electromagnetic survey of the region, where the initial resistivity model is preferably obtained by performing multiple ID inversions of the measured data [100]. The resulting resistivity depth profiles are then registered at proper 3D positions [102]. The 3D electromagnetic response is simulated [106] assuming the resistivity structure is given by the initial resistivity model. The measured electromagnetic field data volume is scaled by the simulated results [108] and the ratios are registered at proper 3D positions [110] producing a ratio data volume [112]. A 3D resistivity volume is then generated by multiplying the initial resistivity volume by the ratio data volume (or some function of it), location-by location [114]. A related method emphasizes deeper resistive anomalies over masking effects of shallow anomalies.

Abstract: This invention relates generally to a method of simulating the signal of an electromagnetic source using one or more dipole sources. In the method a dipole source is located at an excitation location corresponding to a segment of the electromagnetic source to be simulated. The dipole source is activated, and an electromagnetic signal recorded at one or more receiver locations. This process is repeated for additional excitation locations corresponding to additional segments of the electromagnetic source. The data from the sequence of dipole source excitation locations is processed to determine the simulated signal of the electromagnetic source.