PT. PERTAMBANGAN BUMI INDONESIA - PBI Mining

PT. PERTAMBANGAN BUMI
INDONESIA
BRIEF REPORTOF GENERAL SURVEY AT THE
LOCATION OF GENERAL SURVEY MINING
BUSINESS PERMIT FOR
GOLD AND THE ACCESSORY MINERALS
NO. 87 / 2008
GORONTALO PROVINCE
JUNE – AUGUST 2009

Summary
The exploration was carried out in pursuant with the status upgrade upgrade
of Mining Permit to General
Survey Mining Business Permit No. 87 / 2008 28 April 2008.
The General Survey Mining Business Permit is administratively located located
in Pulubala Sub District of
Gorontalo District and Anggrek Sub District of Gorontalo Utara District, Gorontalo Province (inter
district).
Initial exploration was carried out to find out the lithology and mineralization.
The General Survey Mining Business Permit region covers the Northern Northern
tip of Sulawesi island with
mountainous morphology from West to East (1,124 m – 524 m above the sea level), composed of
volcanic rocks and acid intermediate intrusions.
Geological Region of the general survey area (S. Bachri, Bachri,
Sukido and N. Ratman, Ratman,
1993) is located at
the Dolokapa Formation (Tmd ( Tmd) ) and Bone Diorite with lithology of Diorite, Basal Lava, Tuff,
Agglomerate and Tuff Lapili. Lapili.
Main fault is Northeast-Southwest Northeast Southwest Normal Fault piercing through
several stone units/lithology
units/ lithology at both Formations. At the Northern Part, Northwest-East Northwest East rising fault
was found at Dolokapa Formation as well as other minor faults.
Mineralization at the Exploratory Mining Concession site is illustrated illustrated
to take place at contact point of
volcanic stones of Pliocene as well as intrusive rocks of Early Miocene-Middle Miocene Middle Miocene. Main
Northwest (Sumalata ( Sumalata)-Southeast Southeast (Asparaga ( Asparaga) ) Fault located in this area possibly has become
sulphide channel during the mineralization process. Copper and gold gold
mineralization generally
takes place at the epithermal and porphyry zones. The sulphide minerals minerals
found are of chalcopyrite
and pyrite.
Geological Recommended Block covers forest concession area of 1,829.3 1, 829.3 ha consisting of Converted
Production Forest of 657.4, Limited Production Forest of 1178 ha located in Pulubala Sub District
of Gorontalo District (791.3 ha) and Anggrek Sub District of Gorontalo Utara District (1,038 ha) in
Gorontalo Province.

Introduction
General Survey Mining Business Permit No. 87 / 2009 signed on 28
April 2008 covers a region of 8,528 ha for the Gold Exploration and
Accessory Mineral in Pulubala Sub District of Gorontalo District,
Anggrek Sub District of Gorontalo Utara District and Tolangguhula
Sub District of Gorontalo District (inter district).
The Exploratory Mining Concession shall last from June – August 2009.

Exploration Activities
Exploration activities consist of:
Geological Mapping with the scale of 1:50,000
Rock sample taking

Site Map
General Survey Mining Business Permit Block
General Survey Mining Business Permit Block

Site Pictures
Volcanic Breksi
Tuff
Test Pit

Site Pictures
Penggalian – Digging
Aktivitas Dulang – Sieving Activity
Digging
Digging Sieving Activity
Digging

Rock Sample Pictures
secondary gold obtained through sieving activity

Rock Sample Pictures at Other Survey Areas
Tuff with quartz vein
Test Pit

Sample Pictures
Basal
Lava
Basal
Lava
Tuff

Sample Pictures
Meta Diorite
Quartz Monzonite
Diorite

Sample Pictures
Tuf – Tuff
Tuff
Breksi Volkanik – Volcanic Tuff
Volcanic Breksi
Volcanic Breksi

Sample Pictures

Rock Sample Pictures at Other Survey Areas (Outside
General Survey Mining Business Location)
Quartz Vein

MOT87001
MOT87002
MOT87003
MOT87004
MOT87005
MOT87006
MOT87007
MOT87008
MOT87009
MOT87001 B
MOT87009 / 10
MOT87010 / 11
MOT87011 / 12
MOT87012 / 13
MOT87013 / 14
MOT01
MOT02
MOT03
MOT04
Sample No
Summary of Rock Name
122 41 43,1
122 40 49,0
122 40 52,7
122 40 52,9
122 40 50,0
122 40 48,5
122 40 52,4
122 41 21,4
122 47 45,9
122 47 45,9
122 47 18,4
122 47 11,8
122 47 31,5
122
122 47 11
122 41 47,8
122 40 16,6
122 45 57,7
122 45 46,1
X
Total Sample
Coordinate
00 47 11,1
00 45 48,3
00 44 35,0
00 46 27,7
00 46 33,8
00 46 37,4
00 46 41,0
00 46 02,9
00 45 19,9
00 45 19,9
00 45 59,9
00 45 33,7
00 45 24,3
0
00 45 31
00 48 22,8
00 46 02,6
00 44 44,5
00 45 04,6
Y
Diorite
Tuff
Basal Lava
Basal Lava
Meta Diorite
Quartz Monzonite
Diorite
Tuff
Tuff Residual
Volcanic Breksi
Fugy
Volcanic Breksi
Tuff
Diorite
Ademellite
Tuff
Tuff
Rock Name
19 Samples

Map of General Survey Mining Business Permit No. 87
Kecamatan Pulubala – Pulubala Sub District
Kecamatan Anggrek – Anggrek Sub District
Kabupaten Gorontalo – Gorontalo District
Anggrek Sub District
Kabupaten Gorontalo Utara – Gorontalo Utara District
Gorontalo Utara District
Blok Usaha Pertambangan – Mining Business Block
Sungai – River
Batas Kecamatan – Sub District Border
Gorontalo District
Batas Kabupaten – District Pulubala Border
Sub District
Mining Business Block
District Border
Sub District Border
Gorontalo District
River

Coordinate of General Survey Mining Business Permit No.
87 / 2008, Gorontalo Province
No.
1.
2.
3.
4.
5.
6.
122
122
122
122
122
122
West Longitude
40
47
47
40
40
43
24,91
54,1
54,1
2,67
2,67
24,91
0
0
0
0
0
0
North Latitude
48
48
45
45
44
44
9,9
9,9
10,47
10,47
35,94
35,94

Block Path Map dan Geological Structure
Blok KP Penyelidikan Umum – General Survey Mining Block
Stasiun Pengamatan,
Pengamatan,
Pengukuran & Sampling – Observation,
Measuring & Sampling Station
Tambang Rakyat – Public Minery
Sesar Diperkirakan – Estimated Fault
Sesar Naik – Rising Fault
Sesar Normal – Normal Fault
Dulang – Sieving
Test Pit – Test Pit
Sungai Induk – Main River
Anak Sungai – Brook
Batas Kabupaten – District Border
General Survey Mining Block
Observation, Measuring &
Sampling Station
Public Minery
Estimated Fault
Rising Fault
Normal Fault
Sieving
Test Pit
Main River
Brook
District Border

Map of Geological Recommendation
Kecamatan Anggrek – Anggrek Sub District
Kecamatan Pulubala – Pulubala Sub District
Kabupaten Gorontalo Utara – Gorontalo Anggrek Utara Sub District
Kabupaten Gorontalo – Gorontalo District
Gorontalo Utara District
Blok Izin Usaha Pertambangan Penyelidikan Umum – General
Survey Mining Business Block
Gorontalo District
Blok Rekomendasi Geologi Pulubala – Geological Sub District
Recommended Block
Batas Kabupaten – District Border Gorontalo Border Gorontalo District
Batas Kecamatan – Sub District Border
Sungai – River
Mining Business Block
KP Recommendation Block
District Border
Sub District Border
River

Coordinate of Geological Recommendation
No.
1.
2.
3.
4.
122
122
122
122
West Longitude
45
47
47
45
00
54
54
00
0
0
0
0
North Latitude
47
47
45
45
00
00
10,7
10,7

Forest Concession Map
Kecamatan Anggrek – Anggrek Sub District
Kecamatan Pulubala – Pulubala Sub District
Kabupaten Gorontalo Utara – Gorontalo Utara District
Kabupaten Gorontalo – Gorontalo District
Anggrek Sub District
Blok Izin Usaha Pertambangan – Mining Gorontalo Business Utara District
Block
Blok KP Rekomendasi – KP Recommendation Block
Sungai – River
Gorontalo District Batas Hutan – Forest Border Pulubala Border Pulubala Sub District
Batas Kecamatan – Sub District Border
Batas Kabupaten – District Border
HPT: Hutan Produksi Terbatas – Limited Production Forest
HPK: Hutan Produksi Yang Dapat Dikonversi – Converted
Production Forest
Mining Business Block
KP Recommendation Block
District Border
Sub District Border
Forest Border
River
Limited Production Forest
Converted Production Forest

Estimation of Forest Concession Based on Geological
Recommendation
Geological Recommendation
Forest
Concession
Administrative
Location
Estimation
Protected Forest
Converted Production Forest
Pulubala Sub District
Anggrek Sub District
Total Expansion of Geological Recommendation
Area (ha)
1,829.3
1,178
657.4
791.3
1,038
1,829.3

Next Activities
Geological Mapping with scale of 1:25,000 – 1:10,000, namely:
Geophysical research (geomagnetic and induced polarization)

Conclusion and Suggestion
Conclusion
Based on the field research at the General Survey Mining Business Business
Permit No. 87 / 2008, during the initial exploration, the
recommended area of land plot is 1,829.3. This recommended area
is based on the field mapping and observation without taking into into
consideration the petrography and geochemistry analysis
Suggestion
Petrography analysis is to be carried out immediately to identify the
lithological distribution and mineralization. Geochemistry analysis is
to be carried out also to test the concentration and detection limit limit
of
the collected rock samples.
This is for the better of the next exploration.

THANK YOU

Exploration Team
Hendri (Branch Manager – Person-in Person in-Charge) Charge)
Li Jinwei (Senior Geologist)
Liang Wenji (Senior Geologist)
Umar Iribaram (Geologist)
Abram Padaunan (Geologist)
Rayen (Field Assistant)
Asep sujator Possoyo (Field Assistant)
Feri Junaid (Field Assistant)
Alwi Kunjono (Translator & Logistics)
Padda (Driver)