Electromagnetic impulse survey apparatus and method utilizing a magnetic component electromagnetic antenna

A passive geophysical prospecting apparatus, the apparatus comprising:

• a magneto-resistive magnetic sensing antenna, wherein said magneto-resistive magnetic sensing antenna is configured to (i) detect an oscillating magnetic component of electromagnetic radiation naturally emanating from the Earth's surface while blocking a DC component of the electromagnetic radiation and (ii) produce an associated electrical signal while traversing above the Earth's surface;
• a filter, wherein said filter is configured to filter said electrical signal to produce a filtered signal;
• and
• a computer, wherein said computer is configured to analyze said filtered signal to determine the presence or absence of a subsurface deposit of interest;
• and is further configured to provide:
• a level detector for comparing said filtered signal and a reference voltage to determine a pulse count.

A passive geophysical prospecting method comprising the steps of:

• traversing above the surface of the Earth with a magneto-resistive magnetic sensing antenna;
• detecting pulses within an oscillating magnetic component of the electromagnetic radiation naturally emanating from the Earth's surface while removing any non-oscillating magnetic component from said detected electromagnetic radiation with said magneto-resistive magnetic sensing antenna;
• generating an electrical signal from said detected magnetic component;
• establishing a base output pulse count of an area devoid of a deposit of interest;
• and analyzing the difference between a pulse count associated with said electrical signal and said base pulse count to determine the absence or presence of a deposit of interest.

A geophysical prospecting apparatus comprising:

• a magnetic sensing antenna including (i) a magneto-resistive sensor;
• and (ii) a signal amplifier, the mango-resistive sensor and the signal amplifier being operatively coupled by way of a pair of capacitors, the capacitors adapted to decouple a DC current/voltage component in a signal received by the magneto-resistive sensor from the signal amplifier;
• a filter, the filter being adapted to filter from the signal received from the magnetic sensing antenna frequencies below 65 Hz and above 12,000 Hz to generate a filtered signal;
• a level detector adapted to compare the filtered signal to a set reference voltage and registers a count for each pulse in the signal exceeding the reference voltage;
• and
• an analyzer for determining the number of counts per unit of time.