Geophysical MASINT

Template:Wpauthor Geophysical MASINT is a branch of Measurement and Signature Intelligence (MASINT) that involves phenomena transmitted through the earth (ground, water, atmosphere) and manmade structures including emitted or reflected sounds, pressure waves, vibrations, and magnetic field or ionosphere disturbances..

According to the United States Department of Defense, MASINT is technically derived intelligence (excluding traditional imagery IMINT and signals intelligence SIGINT) that – when collected, processed, and analyzed by dedicated MASINT systems – results in intelligence that detects, tracks, identifies, or describes the signatures (distinctive characteristics) of fixed or dynamic target sources. MASINT was recognized as a formal intelligence discipline in 1986. . Another way to describe MASINT is "a "non-literal" discipline. It feeds on a target's unintended emissive byproducts, the "trails" - the spectral, chemical or RF that an object leaves behind. These trails form distinct signatures, which can be exploited as reliable disriminators to characterize specific events or disclose hidden targets"

As with many branches of MASINT, specific techniques may overlap with the six major conceptual disciplines of MASINT defined by the Center for MASINT Studies and Research, which divides MASINT into Electro-optical, Nuclear, Geophysical, Radar, Materials, and Radiofrequency disciplines.

Military Requirements

Geophysical sensors have a long history in conventional military and commercial applications, from weather prediction for sailing, to fish finding for commercial fisheries, to nuclear test ban verification. New challenges, however, keep emerging.

First-world military forces, opposing other conventional militaries, there is an assumption that if a target can be located, it can be destroyed. As a result, concealment and deception have taken on new criticality. "Stealth" low-observability aircraft have gotten much attention, and new surface ship designs feature observability reduction. Operating in the confusing littoral environment produces a great deal of concealing interference.

Of course, submariners feel they invented low observability, and others are simply learning from them. They know that going deep or at least ultraquiet, and hiding among natural features, makes them very hard to detect.

Two families of military applications, among many, represent new challenges against which geophysical MASINT can be tried. Also, see Unattended Ground Sensors.

Deeply Buried Structures

One of the easiest ways for nations to protect weapons of mass destruction, command posts, and other critical structures is to bury them deeply, perhaps enlarging natural caves or disused mines. Deep burial is not only a means of protection against physical attack, as even without the use of nuclear weapons, there are deeply penetrating precision guided bombs that can attack them. Deep burial, with appropriate concealment during construction, is a way to avoid the opponent's knowing the buried facility's position well enough to direct precision guided weapons against it.

Finding deeply buried structures, therefore, is a critical military requirement. The usual first step in finding a deep structure is IMINT, especially using hyperspectral MASINT sensors to help eliminate concealment. "Hyperspectral images can help reveal information not obtainable through other forms of imagery intelligence such as the moisture content of soil. This data can also help distinguish camouflage netting from natural foliage." Still, a facility dug under a busy city would be extremely hard to find during construction. When the opponent knows that it is suspected that a deeply buried facility exists, there can be a variety of decoys and lures, such as buried heat sources to confuse infrared sensors, or simply digging holes and covering them, with nothing inside.

MASINT using as acoustic, seismic, and magnetic sensors would appear to have promise, but the reality of these sensors is that they must be fairly close to the target. Magnetic Anomaly Detection (MAD) is used, in antisubmarine water, for final localization before attack. The existence of the submarine is usually established through passive listening and refined with directional passive sensors and active sonar.

Once these sensors, as well as HUMINT and other sources, have failed, there is promise, for surveying large areas and deeply concealed facilities, using gravitimetric sensors. Gravity sensors are a new field, but military requirements are making it important while the technology to do it is becoming possible.

Naval Operations in Shallow Water

Especially in today's "green water" and "brown water" naval applications, navies are looking at MASINT solutions to meet new challenges of operating in littoral areas of operations . This symposium found it useful to look at five technology areas, which are interesting to contrast to the generally accepted categories of MASINT: acoustics and geology and geodesy/sediments/transport, nonacoustical detection (biology/optics/chemistry), physical oceanography, coastal meteorology, and electromagnetic detection.

Although it is unlikely there will ever be another WWII-style opposed landing on a fortified beach, another aspect of the littoral is being able to react to opportunities for amphibious warfare. Detecting shallow-water and beach mines remains a challenge, since mine warfare is a deadly "poor man's weapon."

While initial landings from an offshore force would be from helicopters or tiltrotor aircraft, with air cushion vehicles bringing ashore larger equipment, eventually, traditional landing craft, portable causeways, or other equipment will be needed to bring heavy equipment across a beach. Shallow depth and natural underwater obstacles can block a beach as well as can shallow-water mines. Synthetic Aperture Radar (SAR), airborne laser detection and ranging (LIDAR)) and use of bioluminescence to detect wake trails around underwater obstacles all may help solve this challenge.

Moving onto and across the beach has its own challenges. Remotely operated vehicles may be able to map landing routes, and they, as well as LIDAR and multispectral imaging, may be able to detect shallow water. Once on the beach, the soil has to support heavy equipment. Techniques here include estimating soil type from multispectral imaging, or from an airdropped penetrometer that actually measures the loadbearing capacity of the surface.

Types of Geophysical MASINT

Many practical MASINT devices combine different MASINT technologies. For example, an unattended truck sensing device, along a highway, might combine geophysical and radiofrequency MASINT. From the geophysical techniques, it would sense the sound of the truck (i.e., acoustic MASINT), its vibrations (i.e., vibration MASINT]), and the mass of metal in the truck (i.e., magnetic MASINT). From the radiofrequency methods, it would detect the electrical noise produced by spark plugs.