The district forms a part of the Gangetic plan which is of recent origin according to geological chronology and revela ordinary gangetic alluvium. The district being apart of the alluvial plain conferm to the same geological sequence as the plain itself. The only mineral of importance is kankar. The district is also noted for its deposits of reh and brick earth.
As stated earlier this district lies in the vast Gangetic plains of north india at an elevation of 100 to 120 metres, sloping gently to south east. Relief from the summer heat arrives with the mansoon in second half of June, through the weather may often remain sultry. The winter sets in November and last upto February Generally
Flora & Fauna
About the 13th century the greater part of the district was covered with extensive forests and in the clear spaces brick dwellings and scattered bamlets of the Bhars were only evidences of human life. During the period of second world war and thereafter in furtherranceof the grow more food campaign, forest in the district were recklessly cut down. The areas of such land already planted with trees like dhak, khair, babul, shishum, neem, vilayti babul, arjuna, kanji, siras, eucalyptus, mango and jamun are 544 hectares in tehsil Raebareli, 500 Hectares in tehsil salon, 348 hectares in tehsil Dalmau and 61 hectares in tahsil Maharajganj.
Groves in the district consist mostly of mango and mahua trees. Tahsil Salon had the largest percentage of its area under groves viz: 8.5%. In 1903 the area covered by the groves diminished to 33,412 hectares. In 1968-69 the area under groves in the district was 28,472 hectares, of which an area of 9,056 hectares lay in tahsil Dalmau, 7,557 hectares in tahsil Maharajganj, 6,611 hectares in tahsil Salon and 5,247 hectares in tahsil Raebareli.
Wild animals have greatly decreased in number and variety in the district during the past century. Tigers and wild buffalos were found in the tamarisk jungles and along the banks of the ganga. The wild boar is seldom seen. The indian antelope has been declared a protected species in the district.
The birds of the district are similar to those of the adjoing districts. The chief game of birds found are several varieties of ducks, patridges and pigeons. The pink headed has become extinct.Green pigeons are becoming rare due to felling of fruit and berry trees. The red headed parrot was formely extensively netted for the sake of its plumage. its skin being sent to kanpur for export to Europe.
Different varities of snakes and other reptiles are found everywhere in the district especially in the rural areas. Some snakes are harmless but some are deadly e.g.,the cobra, krait and rat snake. The other reptiles found in the district are the chameleon, geeko and moniter lizard, at the last, becoming extinct due to netting and shooting, protected species.
Fish are found in the rivers, ponds, canals and artificial reservoirs of the district. About 36 species of fish have been found in this district so far, the chief being the rohu (Labeo rohita), Tengra (Mystas seenghala), parhan (wallagonia attu), mangur(clarius batrachus), saul (ophiocephelus spp.), nain(cirrhina mrigala).