The various geological formations occurring in the Vidisha district are Alluvium, Laterite and Deccan Trap with inter-trapped beds. Alluvium occurs over a large part of the area mainly along the course of streams like Betwa, Sagar, Besh, etc. It consists primarily of yellow or grey brown sandy clay and possesses a large proportion of 'Kankers'. Along the Betwa River it often forms steep cliffs in the Northern part of the area. Laterite occurs in some places as caps on some high trap hills, but usually as ferruginous cellular rocks capping low lying Deccan trap hills, in places surrounded by alluvium. These are used mainly as a road metal. The Deccan Trap is the most widespread rock formation in this district of the Madhya Pradesh state. These rocks are horizontal or nearly horizontal; the dark lava flows lend to the countryside a terraced appearance. The principal rock is basalt possessing vesicles filled with zeolite, agate, calcite, etc. The inter- trappeans, mainly impure crystalline limestone and cacareous chert occur as a residual blocks and boulders scatters over a surface as well as discontinuous outcrops amidst the Deccan Trap. Small isolated outcrops of intertrappeans mostly lime stone are also present in Vidisha. The climate here is generally dry. The nights are generally pleasant and justify the praise by the Mughals for a Shab-E-Malwa famous throughout India. The monsoon comes during the month of June and continues till the end of September. The year may be divided into four seasons. The cold season starts from the month of December and ends in February and is followed by the hot summer season till mid-June. The period from mid-June to about the end of September experiences the South-West monsoon. The month of October and November may be termed the post-monsoon or retreating monsoon. The average annual rainfall received by this district 1,229.9 millimeter. During the summer season on individual days the maximum temperature goes above forty six degree Celsius. After the month of October, both the day and night temperatures steadily decreases till January which is the coldest month. The district is affected by cold waves during the cold season in association with the western disturbances passing across the northern part on India and the minimum temperature may drop down occasionally to a degree or so above the freezing point of water and frosts may occur. |