The assessment of the land use / land cover expansion that occurred in the area over a period of thirty years is the utmost priority of this research work. Multi temporal Landsat satellite imageries TM 1984, 1990 and ETM+ 2002, 2014 from the United States Geological Survey (USGS) website were used as the primary dataset. Area of interest was clipped in ArcGIS 9.3 environment, image enhancement and image classification were adequately done using ENVI 4.5 remote sensing software. Using supervised classification algorithm, the images were classified into bare soil, built-up area, vegetation, water body and wetland; these were then used to carry out change detection analysis or time series analysis. Results obtained from the analysis of built-up area dynamics for the past three decades revealed that the town has been undergoing urban expansion processes. The expansion was prolonged both from urban center to adjoining non-built-up areas in all directions. The total built up area in the town has expanded from 28.04sq/km in 1984 to 49.51 sq/km in 2014 at an average expansion rate of 0.7, 0.4 and 0.9 per annum during 1984 -1990, 1990 -2002 and 2002 -2014 study periods respectively. The study period from 2002 -2014 was the time at which the town experienced the highest urban expansion. The analysis of spatial trend revealed that the urban landscape has experienced a process of sprawling and fragmented development pattern particularly in the fringe areas while the town center underwent infill and edge expansion development processes. The fringe areas show scattered expansion pattern. Quantifying urban expansion patterns and development processes of the past trends can help better understand the dynamics of built up area and guide sustainable urban development planning of the future urban growth.

Geospatial data has been applied for setting structural height restriction around the proposed MKO Abiola international Airport in Ido-Osun, Osun State. The study aimed at using geovisualisation method for guiding structural height restriction around the airport. In Nigeria, there is a growing demand for Airports and safety is paramount to aviation industry as calamity is irreversible. In respect of this, precautionary measures are better emplaced at inception to safeguard the industry as much as possible. For example, failure because of engine faults in flight cannot be completely erased, at least, planes hitting buildings due to either low altitude of the airplane or excessive height of structures could be totally abated. Data used for this study involved Geospatially acquired data obtained through primary and secondary methods. The data were processed and a 2km buffer zone was created around the proposed airport for analysis. Modelling of the study was done to relatively decipher the height relationship between the airport runway and the buffer zone. Hypotenuse theorem was used and available data, airplane altitude along various directions were calculated in relation to the mean sea level through which proposed heights restrictions were made for structures within the buffer zone in the study area. It was scientifically deduced that using of only number of building ,floors and other structures, the height above earth surface are not enough to set such height restriction, instead, elevations of adjoining land should also be a striking factor taken into set structural height restriction aided by Geo observation data.