Abstract:
It is proposed a method for steering a seismic vessel associated with a sail line and a current preplot line. The seismic vessel tows at least one acoustic linear antenna including receivers, the receivers receiving signals generated by at least one source and reflected by subsurface's layers at a plurality of reflexion points. The method includes: a) computing distances di, iε{1 . . . n}, from n reflexion points, included in the plurality of reflexion points, to a boundary of an already obtained binning coverage zone associated with an already used previous preplot line; b) computing a distance D, from the n reflexion points to n target reflexion points, as a function of the distances di; and c) providing steering information comprising or based on the distance D to a navigation system or to an operator of a navigation system, to alter the course of the seismic vessel.
Abstract:
It is proposed a method for steering a seismic vessel associated with a sail line and a current preplot line. The seismic vessel tows at least one acoustic linear antenna including receivers, the receivers receiving signals generated by at least one source and reflected by subsurface's layers at a plurality of reflexion points. The method includes: a) computing distances di, iε{1 . . . n}, from n reflexion points, included in the plurality of reflexion points, to a boundary of an already obtained binning coverage zone associated with an already used previous preplot line; b) computing a distance D, from the n reflexion points to n target reflexion points, as a function of the distances di; and c) providing steering information comprising or based on the distance D to a navigation system or to an operator of a navigation system, to alter the course of the seismic vessel.
Abstract:
Non-constant spatial parameters and/or temporal parameters are assigned respectively to at least one input shot sequence and shot time predictions commuted from a shot sequence, giving flexibility for how and where to shoot during a multi-source survey.
Abstract:
It is proposed a method for steering a seismic vessel associated with a sail line and a preplot line. The seismic vessel tows at least one acoustic linear antenna including receivers, the receivers receiving signals generated by at least one source and reflected by subsurface's layers at reflexion points. The method includes: computing, according to a regression method, a shifted preplot line which has a shape substantially identical to the shape of the preplot line and which is the best fit line associated with at least some of the reflexion points; computing a distance D between the preplot line and the shifted preplot line; and providing steering information comprising or based on the distance D to a navigation system or to an operator of a navigation system, to alter the course of the seismic vessel.
Abstract:
It is proposed a method for steering a seismic vessel associated with a sail line and a preplot line. The seismic vessel tows at least one acoustic linear antenna including receivers, the receivers receiving signals generated by at least one source and reflected by subsurface's layers at reflexion points. The method includes: computing, according to a regression method, a shifted preplot line which has a shape substantially identical to the shape of the preplot line and which is the best fit line associated with at least some of the reflexion points; computing a distance D between the preplot line and the shifted preplot line; and providing steering information comprising or based on the distance D to a navigation system or to an operator of a navigation system, to alter the course of the seismic vessel.
Abstract:
A method is provided for determining a sail path of vessels on a map representative of a marine geographic area, to perform a turn between a start point and an end point, each vessel having a turn radius, the start point, respectively the end point, being associated with a start, respectively an end, circle, the sail path being curvilinear and composed of arcs and straight segments. The method includes: detecting obstacles likely to interfere with at least one vessel; encompassing obstacles into a curvilinear geometric form; determining a sail path of the vessel by minimizing, under constraints, a cost function comprising: a first term representative of the length of arcs making up the sail path and a second term representative of the length of straight segments making up the sail path, taking into account the start and end circles and the curvilinear geometric forms, and a third term of penalization of distance separating the sail path to be determined, at any point of the sail path, and at least one disturbing object.
Abstract:
A method is provided for determining a sail path of vessels on a map representative of a marine geographic area, to perform a turn between a start point and an end point, each vessel having a turn radius, the start point, respectively the end point, being associated with a start, respectively an end, circle, the sail path being curvilinear and composed of arcs and straight segments. The method includes: detecting obstacles likely to interfere with at least one vessel; encompassing obstacles into a curvilinear geometric form; determining a sail path of the vessel by minimizing, under constraints, a cost function comprising: a first term representative of the length of arcs making up the sail path and a second term representative of the length of straight segments making up the sail path, taking into account the start and end circles and the curvilinear geometric forms, and a third term of penalization of distance separating the sail path to be determined, at any point of the sail path, and at least one disturbing object.
Abstract:
A method if provided for determining a sail path of at least one vessel on a map representative of a marine geographic area, to perform a turn between a start point and an end point. The start point is associated with a start circle, and the end point is associated with an end circle having a predefined radius of curvature. The sail path is curvilinear and composed of arc segments and straight segments. The method includes: detecting, in the map, obstacles likely to interfere with the at least one vessel; encompassing each obstacle into a curvilinear geometric form; determining a sail path of the given vessel by minimizing, under constraints, a cost function including: a first term representative of the length of arc segments making up the sail path and a second term representative of the length of straight segments making up the sail path, taking into account the start and end circles and the curvilinear geometric form into which is encompassed each obstacle.
Abstract:
Method for obtaining an adapted sequence of M shot predictions (tn) from a raw sequence of M shot predictions (s), including: for a constraint type, determining one or several fixed constraints and several free constraints; for the constraint type, selecting only a part of the free constraints, based on the fixed constraint(s), N free constraint(s) being selected; transforming each fixed constraint into a first equality constraint and each selected free constraint into a second equality constraint; at least for a given constraint pattern (including the first equality constraint(s) and some or all of the second equality constraint(s)): minimizing, under the given constraint pattern, a function having as argument a part or all of a sequence of M residuals (xn), with xndef tn−sn; and verifying the equality constraints of the given constraint pattern are enforced with the result of the minimizing step; obtaining the adapted sequence from the result and the raw sequence.