Over the years, our staff have utilized and processed multi-spectral and high-resolution imageries for numerous regional and sub-regional studies of natural physical features including fractures and lineaments, geologic structures, soil and rock types, resulting in more details and greater accuracy.
Satellite Imagery Analysis and Interpretation
Fracture/Lineament Trace Analyses
Fracture-trace or lineament analysis is a technique that makes use of surface features on aerial photographs and satellite imageries to locate zones of structural weaknesses within the earth’s crust. These structural zones are usually between two and 20 meters and may be continuous for distances in excess of a kilometre. They may contain just a fracture system or several fracture systems. The use of lineament in selecting well sites is most useful in consolidated rock terrains such as igneous, sedimentary and metamorphic rocks where groundwater is confined to “breaks” in the earth’s crust.
Fracture trace analysis is not a straightforward technique, but rather an act. However, MEK staff have widely and successfully used this technique as our first line of action in groundwater exploration in some of the most difficult hydrogeological terrains. We have the training and skill set to identify natural linear features that are indicative of the presence of groundwater in “tight” hydrogeological terrains. Our efforts have improved well drilling success rate by 20 to 85 percent and have also led to significant increments in well yields i.e., amount of water coming from the well.
Land Use and Land Cover Changes
MEK has the expertise to conduct comprehensive land cover and land use studies using a combination of remotely sensed data and Geographic Information System techniques to identify, delineate and map land cover (vegetation, water bodies, soils, urban infrastructure etc.) for resource planning, management, monitoring and determining long-term changes in land cover and usage. Our team have the experience to utilize information collectively derived from topographic maps, remotely senses data, aerial photographs, G.I.S and field studies to successfully carry out the following:
- Baseline mapping for G.I.S. Input;
- Urban Expansion/Encroachment studies;
- Natural Resources Management;
- Routing and logistics planning;
- Damage delineation;
- Target detection e.g. land/water interface, roads etc.; and
- Identification and categorization of natural and man-made attributes using an appropriate classification system.
Using remotely sensed data, GIS techniques and an appropriate classification system and theme, our team will undertake and successfully complete the following studies for our clients in the agricultural sector.
- Assessment of degraded land;
- Soil categorization and mapping;
- Assessment of irrigated agricultural lands;
- Inventory and mapping of agricultural lands;
- Farm planning and plot layout; and
- Assessment of changes in agricultural land usage overtime.
Satellite imagery analysis and interpretation can be invaluable in the analysis, assessment and management of forests. In general, this analysis will require accurate “land cover and change” analysis. MEK has the experience to conduct comprehensive studies related to urban sprawl, forest fragmentation, land cover and change detection analysis to assist in making informed decisions regarding the management of ecosystem species diversity, forest health, reforestation, soil conservation, water resources, and nutrient cycling.
The advantage of synoptic coverage of the earth’s surface by satellite imageries and aerial photographs has made possible the analysis of geological features at regional scale level. Over the years, our staff have utilized multi-spectral and high resolution and decipherable imageries to identify different soil and rock types and delineate geologic structures in more detail with greater accuracy; determine or/and reconstruct structural geological features such as fold and faults and possible locations of natural deposits (hydrothermal alterations) within different rock formations.
Information derived from the analysis of remote sensing data or satellite imageries can provide very useful information for regional site investigations and planning. Using remotely sensed data and GIS information, MEK will analyze and provide invaluable topographic (terrain) and geological (soil and rock type) information to assist in formulating sound engineering development plans. Our capable staff will conduct Terrain Mapping and Analysis assessment using Digital Elevation Models for specific engineering investigations when requested.
Geophysics is the application of the principles of physics to the study of the Earth. Different earth materials have different physical properties (densities, acoustic velocities, elastic moduli, electrical conductivities, magnetic susceptibilities, and dielectric constants). As such geophysical survey are designed and conducted to map the spatial variation in these physical properties of the earth. Geophysical investigation techniques have provided clear insights and therefore solutions to a wide range of groundwater, environmental and engineering problems.
There are approximately 12 common geophysical techniques. MEK geophysicists have deployed several of these techniques over the years including frequency Electromagnetic (FEM), transient electromagnetics (TEM), electrical resistivity, Ground Penetrating Radar and seismic refraction techniques.
MEK has provided geophysical consultancy services in the following areas:
We have successfully used electromagnetic techniques to locate prolific water-bearing aquifers in consolidated rock aquifers over the years. In particular our geophysicists have utilized EM-34 to locate relatively shallow (< 30m) and narrow water-bearing fractured zones in igneous and meta-sediments. For deep geophysical sounding to locate aquifers, MEK geophysicists have significant experience and have used the transient electromagnetic technique to successfully locate stratigraphic units and also discriminate between fresh and saline aquifers.
The MEK team has also used the DC electrical resistivity technique to locate nearly horizontal to horizontal inter-bedded permeable water-bearing stratigraphic units sandwiched between non-water bearing formations. In a number of circumstances, our geophysicists have jointly used the DC electrical resistivity and TEM techniques to locate fresh water aquifers. Our geophysicists will ensure that the most productive and sustainable aquifers are selected for development.
Our team has used electromagnetic techniques (EM 31 and EM 38) extensively to map spatial distribution of soil attributes including clay content, soil moisture, soil salinity, contaminant plumes and landfills. We have also successfully deployed these techniques in locating buried objects such as tanks and pipe lines. Our vast experience in this area has prepared us to conduct these surveys under any environmental setting.
Engineering Geological Investigations
MEK geophysicists have been involved in numerous subsurface site investigations, integrating traditional geologic mapping, intrusive sampling and of geophysical profiling and sounding techniques to obtain an in-depth characterization of site conditions at reduced cost to our numerous clients. Using combinations of the above mentioned techniques, MEK geophysicists have successfully addressed numerous challenges arising in the construction industry.