Summary:
The Kamptee Coalfield is within the command area of WCL and is located in the northern part of Pranhita-Godavari Valley Basin. The area under consideration falls in the Kamptee-Silewara-Patansaongi Sub-basin of Kamptee Coalfield.
Incrop / Outcrop of Coal Seam(s)
Five coal seams which are characteristic of Kamptee Coalfield. All these seams occur in the Middle Barakar horizon of about 100 m thickness. The seams in Kamptee Coalfield are numbered from bottom to top, the bottom-most Seam-I is the oldest, while the top most Seam-V is the youngest. The oldest Seam-I is found to be deposited around 100 m above the Talchir-Barakar contact. Of the five seams, Seams-II, III & IV occur in 2 to 3 split sections, while Seam-V is present as a single horizon. Seam-I is impersistent and also thin, mostly below 0.90 m thickness.
While Seams II, III and V generally occur as Composite Seams over major part of the coalfield, seam I and IV exhibit splitting tendency throughout the coalfield. The split sections have been designated as Top, Bottom etc. It has generally been observed that there is a progressive reduction in thickness of individual seams when traced from east to west. In the western part of the coalfield i.e. "Saoner-Bharatwada sub basin" this phenomenon is more pronounced when traced from north to south. Further, splitting of seams II and III also is observed.
Adasa UG to OC mine
Total Nine seam-sections namely Seam: V, IV (T), IV T (A), IV (M), IV (B), III (T), III (B), II (T) & II (B) have developed in the Adasa block. Out of these seam-sections, the upper seam-sections from top most seam-V to Seam-IV (B) have developed in most part of the mine area, hence these seam sections – (Seam V, IV (T), IV T(A), IV (M) & IV (B)) have been considered for mining. The lower seams below IV (B) are partly developed, thin and inconsistent and therefore the reserves of these seams (Seam-IIIT, IIIB, IIT & IIB) have not been considered for mining. However, as suggested by CMPDI (HQ), during presentation of Draft PR for Adasa UG to OC mine, the possibility of mining Seam-III (T) should be ascertained during actual operation of the mine.
The incrop of Seam-IVB defines the mine boundaries in the North side (Rise side), East side and west side. In the south side (dip side) of the property, fault F12-F12 (of about 190 m down throw) exists. In the upthrow side of fault, Adasa block is situated while in the down throw side of fault, Silori block is situated. In the proposed Adasa UG to OC, it is envisaged to extract coal upto this dipside fault. In the eastern dip side area, the quarry surface of Adasa OC will extend in mine boundary of proposed Silori OC. Since, the dip side quarry batter of Adasa UG to OC mine and side batter of Silori OC mine overlap, boundaries between Adasa UG to OC and Silori OC may be adjusted in future depending upon the sequence of working of the two mines in this area.
Amalgamated Inder-Kamptee Deep OC mine located in Northern limb of Kamptee Coalfields with seven workable seams (II(B), II(T), III(B), III(T), IV(B), IV(T), V) with thickness ranging from 0.90 m to 15.68 m.
The Gondegaon-Ghatrohan Block is a part of the Kamptee-Silewara-Patansaongi Sub-basin. The general strike of beds is ESE-WNW to NW-SE. The gradient of the coal seams varies from 1 in 3.5 to 1 in 5 due SW to SSW.
Seam - II to V occur in Gondegaon-Ghatrohan Block in nine sections: Seam-I (Bottom), I (Top), II (Bottom), II (Top), III (Bottom), III (Top), IV (Bottom) {Seam-IV Bottom and IV Middle may be considered as Seam-IV Bottom due to very thin parting between them}, IV (Top) & V.
Strike and Dip
The strike and dip of the coal seam in the proposed area is entirely based on the sub-surface data obtained from the boreholes. The floor contours of the composite seam has been drawn at 10 m interval from which it would be seen that the amount of dip and strike direction are quite variable.
Patansaongi UG Mine is located in Kamptee-Silewara Coalfield.
The mining area in Patansaongi U/G Mine is having four workable seams/ sections namely Seam-V, Seam-IVM, Seam-IVB and Seam-II in the descending order. Seam-V is having a thickness of 1.50m to 4.56m. This seam has been developed in the rise side of mine area but is virgin on the dip side. Seam-IVM is having a thickness of 2.70m to 3.00m. Maximum development has been carried out in this seam because of its good roof. Some virgin area is available in this seam. The seam has been partly depillared. The parting between Seam-V and IV(M) Seam is 32-35.0m. Seam-IVB is having a thickness of 1.22m to 2.61m. This seam section too is partly developed and partly depillared. The parting between Seam IV(M) and IV(B) is 5-6.0m. The balance depillaring reserves have been estimated in the pillars which are standing in this seam section. Seam-II is having a thickness of 2.10m to 6.62m. This seam behaves as a composite seam in 50% of the mine area and splits into top and bottom sections in the remaining part of mine area. This seam has the best quality coal and good roof condition. In the workable area, this seam has been fully developed and partly depillared. The parting between IV(B) and Seam-II varies from 40-45m.
Faults:
The Patansaongi Block and a part of Zone-3 have been affected by faulting. The faults have been deciphered on the basis of floor contours drawn for the various seams and their presence in actual workings of Seam –IVB. In all 11 faults have been deciphered in this area. Of all these faults, two faults F2-F2 & F3-F3 are strike faults, three fault F1-F1, F5-F5 and F12-F12 are dip faults and the rest are oblique faults. While F2-F2 is a major fault having a throw of nearly 20-30 meters,the throw of other faults varies between 5 and 15 meters only.
The two strike faults F2-F2 and F3-F3 are located almost in the middle of the property. These two strike faults hade against each other as a result a narrow horst block has been formed almost in the middle of the property. The eastern & north eastern part of the area exhibits presence of minor faults/slips as encountered in present workings of Patansaongi UG Mine.
Intrusives:
The Kamptee-Silewara Coalfield in general and Patansaongi Expansion area inparticulars is free from any igneous intrusives as evidenced from the mining activities as well as the drilling operations conducted.
In the Saoner underground mine, of 11 seams/ sections of the Kamptee coalfield only 3 seams/ sections are workable: seam V, seam IV(M), and seam IV(B).
Strike & Dip
The Saoner Sub-basin is separated from the main Kamptee basin by a narrow strip of Talchir formation. Like Kamptee basin, this sub-basin is too covered by a thick cover of black cotton soil and detrital mantle. As a result, no exposure is available. A few hillocks can be seen here and there representing Kamthi formation that underlies unconformably over the older Barakar formation.
Saoner 1 UG Expansion mine
Seam section IVT has attained workable thickness of + 1.5m in a small patches but has to be surrendered on account of contiguity with sections IVM and IVB. Seam Section-IVM has been extensively developed in Saoner UG Mine-I area and also extracted in areas where it is not overlain by Seam-V. Wherever, Seam Section-IVB has attained a thickness of +1.5m, it has been developed in contiguity with section IVM and also extracted in those areas where IVM has been extracted.
The thickness of Seam-V is varying from 2.4m to 5.74m normal range being 4.00 to 5.00m. The thickness of Seam Section-IVM is varying from 2.12 to 8.53m normal range being 4.50 to 5.00m. The seam gradient is varying from 1 in 7 to 1 in 15. In northern part of the mine upto around 25L, the seam gradient is 1 in 4.