Applied mineral exploration methods, hydrothermal fluids, baro-acoustic decrepitation, CO2 rich fluids #
Newest Topics:

Exploration of the Mt. Boppy Au deposit, NSW

Forensic tests on soil samples

Gold at Okote, Ethiopia


Do IOCG deposits form from CO2 fluids?

How CO2 inclusions form from aqueous fluids (UPDATED)

Understanding heterogeneous fluids : why gold is not transported in CO2-only fluids

Gold-quartz deposits form from aqueous - CO2 fluids: NOT from CO2-only fluids

Discussions why H2 analysis by mass spectrometry is wrong


Kalgoorlie Au data

Sangan skarn Fe deposits, Iran

New models 205 & 216 decreptiometer

Studies of 6 Pegmatite deposits

A study of the Gejiu tin mine, China

Exploration using palaeo-hydrothermal fluids

Using opaque minerals to understand ore fluids

Understanding baro-acoustic decrepitation.

An introduction to fluid inclusions and mineral exploration applications.

 Interesting Conferences:


ECROFI 2021, Reykjavik, Iceland

SGA, Rotorua NZ, RESCHEDULED to march 28-31 2022
6th Archean, Perth, W.Aust. RESCHEDULED unknown date 2022

Comprehensive Geology Conference Calendar

Sample descriptions and analyses provided by the site geologist

Listed in Drillhole-depth order

Depths listed are the beginning of the interval over which the gold is analysed. Most samples were of about 1m length and there is no information available indicating just where the decrepitation sample was collected within that interval. Consequently even adjacent samples could be 2m apart and from entirely different quartz events.

The CO2 column indicates the presence of decrepitation peaks of about 400 counts in the 200 to 300 C region. Many other samples have low level decrepitation at these temperatures indicating smaller amounts of CO2-rich fluids in the inclusions.

Sample descriptions listed in sample number order

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Sample  # Run  Hole  Depth  m Au  As  Description CO2

NG12202  g1855 BDD1 537 0.24 5200 Slightly murky, minor CO3
NG12201  g1834 BDD1 542 17.0 14800 Slightly cloudy vein qz, small sed frags, minor CO3
NG12204  g1835 BDD1 549 0.05 2000 Coarsely xtl buck qz, slightly cloudy
NG12203  g1856 BDD1 550 <0.02 65 Coarsely xtl buck qz, slightly cloudy
NG12205  g1858 BDD1 555 7.6 9050 Cloudy, massive vein qz, 30% sed frags. Yes
NG12206  g1836 BDD1 561 13.9 1000 Cloudy, massive, minor sed impurities

NG12221  g1867 BDD1A 467 28.5 850 Murky, fine gr. massive, orange dolomite frag. Yes
NG12222  g1868 BDD1A 479 0.07 600 Mod gr. v. slightly murky, fine dolomite on fracts Yes
NG12220  g1866 BDD1A 493 5.6 2450 Slightly murky mod xtl qz, minor CO3

NG12223  g1869 BDD1B 451.5 43.0 2500 Slightly murky fine-mod gr.  with sed and CO3 Yes
NG12224  g1844 BDD1B 454.4 3.43 5500 Slightly murky, mod gr., minor sed frags.
NG12225  g1870 BDD1B 456.8 0.22 2200 Slightly murky, mod-coarse gr., minor sed. tr.

NG12226  g1871 BDD1C 547.5 4.5 14000 Slightly murky, mod-coarse xtl., sed frags.

NG12219  g1843 BDD2A 232.8 <0.02 <50 V. clean white coarse xtl buck qz
NG12218  g1865 BDD2A 243.6 120.0 8500 Greyish fine gr. mass qz, minor chlorite, sed
NG12217  g1841 BDD2A 255.1 <0.02 50 Clean coarse xtl Yes
NG12216  g1840 BDD2A 263.3 0.14 50 Slightly murky coarse xtl, thin dolomite laminations
NG12227  g1845 BDD2A 650 0.15 ? Clean coarse xtl qz

NG12228  g1872 BDD2C 534 <0.02 50 Clean slightly murky, fine gr., much CO3

NG12229  g1873 BDD2D 245 2.48 1250 Clean, coarse xtl, minor CO3
NG12230  g1874 BDD2D 245.7 0.02 <50 Slightly murky, med-cse gr., cse aspy & dolomite
NG12207  g1859 BDD2D 464.8 0.44 1150 Coarsely xtl clean-sltly cloudy, minor CO3 Yes

NG12232  g1876 BDD2E 238.2 <0.02 50 Slightly murky, med-cse gr, with py & CO3 & sed
NG12231  g1875 BDD2E 238.9 11.3 200 Slightly murky, cse gr., chloritic slatey frags

NG12233  g1846 BDD3A 461.4 0.05 250 Slightly murky, med-cse gr. Yes
NG12234  g1847 BDD3A 461.9 7.8 950 Slightly murky, cse gr., minor slatey frags
NG12236  g1849 BDD3A 472.8 0.04 150 Cse xtl clean white buck qz tr.
NG12235  g1848 BDD3A 473.9 1.76 1850 Slightly murky, fine gr.,  mass., + sed & CO3 & py. Yes

NG12237  g1877 BDD3B 474.2 1.85 4150 Slightly murky, fine gr.,  mass., + sed & CO3 & py.
NG12238  g1850 BDD3B 477.1 0.05 200 Coarsely xtl clean white buck qz.
NG12213  g1839 BDD3B 647 0.06 2500 Slightly murky, massive, minor S= & CO3
NG12211  g1862 BDD3B 649.3 0.03 150 Slightly murky, med grain, coarse aspy, minor CO3
NG12208  g1860 BDD3B 653.5 0.02 50 Clean, coarse xtl, minor sed and CO3
NG12212  g1838 BDD3B 654.7 0.06 250 Slightly murky, coarse xtl qz

NG12210  g1861 BDD4 646.5 13.3 16000 Slightly murky qz, v. minor sed frags
NG12209  g1837 BDD4 655.3 220.0 750 Slightly murky qz, v. minor sed frags

NG12214  g1863 BDD4A 644 21.6 50 Slightly murky, mod grain, minor CO3
NG12215  g1864 BDD4A 648.5 275.0 4600 Coarse xtl, clean qz, minor sed

NG12239  g1878 BDD4B 567.8 16.5 1300 Grey murky fine-med gr., sed & CO3 frags
NG12240  g1852 BDD4B 573.7 16.8 8850 Mod gr., clean white buck qz

NG12241  g1879 BDD4C 476.6 0.13 <50 Med gr., slightly murky qz, minor dolomite tr.

NG12242  g1880 BDD5 251.9 <0.02 400 Med gr. murky qz
NG12243  g1881 BDD5 261 0.03 250 Coarse xtl. slightly murky, sed frags.

NG12244  g1882 BDD5A 240.2 6.2 <50 Clean coarse xtl qz, minor CO3
NG12245  g1883 BDD5A 245.5 0.02 <50 Fine-med gr., murky, + cse. aspy.
NG12246  g1853 BDD5A 253.6 <0.02 <50 Slightly murky, mod-coarse xtl.

NG12248  g1854 BDD5B 258.9 30.0 600 Slightly murky coarse xtl., clean qz
NG12247  g1851 BDD5B 266.4 0.04 <50 Slightly murky, coarse xtl, clean. Yes


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