This document provides an executive summary of a regional assessment of limestone reserves conducted from 1997-1998 in the Bher-Dhingsara area of Nagour district, Rajasthan, India. Key findings include: - Drilling of 14 boreholes found cement-grade limestone between 3-6 meters thick in 9 locations, with a total thickness of 397 meters across the block. - Based on a thickness of 5.25 meters, tentative geological reserves of 99.42 million tonnes of limestone were estimated across the 8 square kilometer limestone-bearing area. - Samples analyzed indicated limestone with 44-54% CaO, suitable for cement production.

1. GOVERNMENT OF RAJASTHAN
MINES AND GEOLOGY DEPARTMENT
UDAIPUR
Executive Summary
Project JDP-1, 1997-98,1998-99
Regional Assessment of Limestone by drilling in Bher-Dhingsara
area, teh. Khimsar, dist. Nagour,Rajasthan.
By
Rakesh G.Goswami
Geologist
Office Of Superintending Geologist,
Mines & Geology Department
Jodhpur
2010

2. REPORT ON LIMESTONE AVAILABILITY IN
DERESERVED BLOCK OF 7.65 sq km. n/v BHER-DHINGSARA,
TEH. KHIMSAR, DISTT. NAGOUR.
1. Introduction :- Department of Mines and Geology has been
engaged in exploration of limestone in distt. Nagour for last
one decade. For this purpose an area of 476 sq.kms. was
reserved (block no.4) few years ago. The exploration has
resulted in identification of areas having sufficient reserves
of cement to chemical grade limestone. Blocks for such
limestone have also been notified from time to time. The
present area is northern extension of Tankla block. The work
in present block was conducted in 1997-98,1998-99. The
work included regional survey and mapping. Beside 397 mts.
drilling was also done, spread over 14 bore holes, out of
which 9 have intersected limestone having 3.0 to 6. mts.
thickness. The thickness of overburden varies from 3 to 5
mts. Area covered by drilling is 12 sq. km. but out of it
limestone bearing area is about 8.0 sq.km. Drilling was
carried out at 1km. x 1km., 1km. x 800 mts. grid interval.
Considering 5.25 mts. thickness in limestone bearing area,
about 99.42 MT reserves have been assessed tentatively.
2. Location & Approch :- The area under consideration is
covered under toposheet no.45E/8, village Bher-Dhingsara
teh Khimsar,distt.Nagour. The area can be approached from
Jodhpur and Nagour by NH-65 via Khimsar and Tankla. The
Tankla – Bher tarred road passes through the centre of this
block. Dhingsara is also connected by tar road with Bher
Tankla road. The N-S limit of block is 5 km. from Bher-
Tankla villages.

3. 3. Physiography :- Area is part of desertic terrain, it shows
slight undulating topography due to sand dunes and mounds.
Area shows extremes of hot and winter climate. The min. and
max. temperature are 45ºc and 2ºc. respectively.
4. Infrastructure :- The area has good infrastructure in terms
of road, rail, water, communication and power facilities.
Proposed block is 7 kms. from NH 65, nearest rail head is
Nagour,(40kms. from block) which is located on Merta -
Bikaner broad gauge section. Area is completely electrified
through 32 kv lines. GSS are located at Bher and Khimsar
water supply is through tube wells, ponds, handpumps etc.
5. Geological set up :- Geologically area comprises rocks of
Marwar Super Group. The main lithounits are cherty
limestone, dolomitic limestone, grey limestone of Bilara
Group. These are overlain by sandstone of Nagour group and
lime kanker formation of recent age at places. Most of the
area is covered by sand/sand dunes and exposures are scanty.
Rocks of Jodhpur group are not found and likewise Tunklia
sandstone, of Nagour group is not observed in the area.
However general geological succession is as under-
Recent age Lime Kanker, Gravel and blown
sand
Cambrian age
Mar
war
Super
Nagour Group Tunklian Sandstone-Gritty pebbly
Sandstone
Nagaur Sandstone-Sst., Siltstone
with evaporates.
Bilara Group Pondlo dolomite-
Dolomite,DoloLst, Stromatolitic
Lst. Siliceous oolites.
Gotan Lst. Lst. with bands of chert
& dolomite
Dhanapa- Chert, dolomite,
dolomitc lst. dolomite

4. Gr
oup
Jodhpur Group Girbhakar Sst.-Sandstone, Shaly
Siltstone.
Sonia Sst.-Sandstone, Sahle,
Siltstone
6. Quantum of work :-
Target and achievement position is tabulated below :-
S.No. Item Total
Target
Achiev.
During
1997-
98
Achiev.
During
198-99
Total
Achiev %
1 2 3 4 5 6 7
1. R.M.S. 150 km² 100
km²
50 km² 150
km²
100%
2. R.G.M 20 km² 10 km² 10 km² 20 km² 100%
3. D.G.M 2 km² 1 km² 1 km² 2 km² 100%
4. DRRILING 1000mts 286m. 111m. 397m. 39.7%
5. SAMPLING
(Core Spot)
AS Req. C-95
S-22
C-38
C-50
133nos
72nos
--
7. Occurrence and Nature of Limestone :- The major part of
area of this block is covered either by ag. fields or by sand
dunes. Rock exposurés are scanty and occur as small
mounds. The information of out crops is deciphered by
numerous pits, tanka and tubewell sections in the area. In pits
dolomitic lst. is exposed below soil cover, followed by grey
laminated limestone having 2 to 3 mts. thickness. The
analysis of pit samples have indicated that this grey limestone
is of cement grade nature.
In tanka and tube-well sections it is observed that limestone
is underlain by dol.lst. and dark red to maroon shale/shaly
limestone. This shale is of calcareous nature as it gives
effervescence with acid.

5. 8. Drilling : - Drilling on 1km x 1km grid was started in 1997-
98 but due to presence of sand dunes and agriculture fields,
the grid could not be maintained as such and slightly reduced
according to status of land/physiography etc. to 1km x 800m.
However total 397m drilling could be achieved spread over
14 vertical bore holes located in the south of Bher and SW of
Dhingsara village.
Drilling work concluded in the year 1998-99. Drilling has
indicated presence of subsurface cement grade limestone
zone having 3 to 6m thickness over 9 bore holes. This
limestone occurs at a depth or 3 to 5mts. from surface. The
main lithounits encountered in bore holes are limestone,
dolomitic limestone, &shale/ shaly limestone. 5 bore holes
have been proved as barren in which only shaly limestone &
dolomitic limestone has intersected.
Table showing depth wise details of intersecting
formation is enclosed as Annexure-I Summarized core logs
are also appended as Annexure-II.
9. Grade & Reserve :- During regional and details mapping
samples were collected from pits. The analysis of surface
samples have indicated 47-54% CaO, 1.0 to 7.6% SiO2, 0.80
to 1.60% MgO. The analysis of core samples indicated 44-
54%CaO, 1.60 to 10% SiO2, MgO up to 3% as such
limestone of the block is suitable for cement making.
Since exploration was only a regional study reserve estimate
has been attempted in following manner. Av.thickness is
taken as 5.25mts.sp.gr. as 2.5.one the basis of this 99.42 MT
geological reserves are assessed tentatively in 7.65 sq.km
Reserves are calculated for first zone of limestone. If
shale/shaly limestone is also used after addition of suitable
sweetner, then reserves will be increased.

6. 10. Land Status :- Mostly Khatedari.
11. Expenditure :- The project expenditure has been
calculated as per the current schedule of rates. :-
Work Rate (Rs.) Amount (Rs.)
RMS 150 sq. km. Nil Nil
RGM 20 sq. km. 1000/ sq.km. 20,000/-
DGM 2 sq. km. 150 / Hect. 30,000/-
DRLLING 397 m. 2800 /mt. 11,11,600/-
LOGGING 397 m. 6 / m 2,382/-
SAMPLING Core-133 20/ sample 2,660/-
Spot-72 10/ sample 720/-
ANALYSIS 205 400/sample 82,000/-
REPORT Up to two copies Nil Nil
More than two
copies
500/each 1500/-
TOTAL 12,48,448/-
Supervision
1,24,484/-
charges 10%
TOTAL 13,72,932/-
Service tax 10% 1,37,293/-
TOTAL 15,10,225/-
Cess 3 % 45,306/-
Grand total 15,55,531/-
IN WORDS :- RS. Fifteen Lakhs, Fifty Five thousand, Five
hundred Thirty one.

7. Annexure – I
Bhorehole wise summary of limestone zones :-
S.No. Boreholes
No.
Depth
in mts.
Limestone Total Remarks
From To OB/IB
1 BDH-1 30 3.0 9.0 6.0 Sand/Alluvium
2 BDH-2 25 Barren Mainly Dol. lst.
3 BDH-3 30 3 9.0 6.0 Sand/Alluvium
4 BDH-4 30 6.0
18.0
12.0
24.0
6.0
6.0
Sand/Alluvium,
pieces of
Dol.lst.
5 BDH-5 30 16.0 18.0 2.0 Sand/Alluvium
Dol.Lst.
6 BDH-6 30 Barren Loose
Sand/Sludge
7 BDH-7 30 Barren Loose
Sand/Sludge
8 BDH-8 30 3.0 6.0 3.0 Loose Sand
9 BDH-9 21 Barren Sludge of Shale
10 BDH-10 30 1.0 6.0 5.0 Sand
11 BDH-11 30 1.0 6.0 5.0 Sand
12 BDH-12 30 0.50
15.0
3.0
16.0
2.50
1.0
Loose Sand
Shale
13 BDH-13 30 3.0 9.0 6.0 Loose Sand
14 BDH-14 21 Barren Loose Sand
Sludge Grey to
Brown