Bailey, et al. 1924. Tertiary and Post-Tertiary geology of Mull, Loch Aline, and Oban (a description of parts of sheets 43, 44, 51, and 52 of the geological map). HMSO [for Geological Survey]

Tables Revised

(Table 1) Plateau Magma-Type of Figure 2

A B I. II. III. C1 D E
SiO2 43.94 45.24 45.37 45.48 45.52 46.46 46.61 47.64 SiO2
TiO2 2.45 2.26 2.87 3.48 2.85 2.07 1.81 1.27 TiO2
Al2O3 14.03 15.63 15.16 15.66 14.30 15.48 15.32 14.15 Al2O3
Cr2O3 tr. tr. — — — 0.02 tr. 0.01 Cr2O3
V2O3 — — — — — 0.05 — 0.06 V2O3
Fe2O3 1.95 5.56 3.38 3.64 3.43 3.63 3.49 5.18 Fe2O3
FeO 11.65 7.19 11.58 10 56 9.00 10.23 7.71 7.96 FeO
MnO 0.32 0.23 0.31 0.20 0.19 0.48 0.13 0 33 MnO
(Co,Ni)O nt. fd. tr. nt. fd. — — 0.02 tr. tr. (Co,Ni)O
MgO 10.46 7.82 6.72 6.99 10.65 6.80 8.66 7.38 MgO
CaO 8.99 9.38 8.11 8.24 9.54 9.05 10.08 11.71 CaO
(Ba,Sr)O nt. fd. — nt. fd. — — 0.02 — nt. fd. (Ba,Sr)O
Na2O 2.68 2.1 2.90 2.68 2.1 3.01 2.3 2.38 Na2O
K2O 0.33 0.72 0.44 0.49 0.42 0.68 0.67 0.71 K2O
Li2O nt. fd. — nt. fd. nt. fd. nt. fd. ? tr. — — Li2O
H2O +105° 2.31 2.21 1.96 1.52 1.53 1.43 2.07 1.44 H2O +105°
H2O at 105° 0.85 1.12 1.18 0.93 0.70 0.89 1.10 0.19 H2O at 105°
P2O5 0.20 0.20 0.29 0.26 0.23 0.30 tr. 0.09 P2O5
CO2 0.16 0.49 — 0.21 0.15 nt. fd. tr. — CO2
FeS2 0.04 — — — — — — — FeS2
Fe7S8 0.06 — — — — — — — Fe7S8
½S — — — — — 0.08 — — ½S
S — — — nt. fd. nt. fd. — — 0.03 S
100.42 100 06 100.27 100.34 100.72 100.70 100.08 100.53 —
Spec. grav. — 2.85 2.95 2.93 2.99 — 2.87 — —
Table I.: Plateau Magma-Type of (Figure 2)

A. (S14174) [NR 440 731], Lab. No. 339). Dyke. Slac nan Sgarbh; Jura. Crinanite, quoted from J. S. Flett, Geology of Knapdale, Jura & North Kintyre, 1911, p. 118. Anal. E.G. Radley.

B. (S7854) [NG 502 336], Lab. No. 22). Sill. Ben Lee; Skye. Dolerite, quoted from A Harker, Tertiary Igneous Rocks of Skye, 1904, p. 248. Anal. W. Pollard.

I. (S15995) [NM 5412 2210], Lab. No. 390). Lava. Stream at pit, ⅓ m. N.N.E. of Pennycross House, 750 ft. above sea; Mull. Basalt, p. 137. Anal. E. G. Radley.

II. (S19070) [NM 6786 4463], Lab. No. 460). Lava. Raised-beach cliff, 200 yds. W. of Lochaline Pier, between first two walls crossing raised beach west of Pier; Morven. Basalt, p. 136. Anal. F.R. Ennos.

III. (S19071) [NM 6633 4446], Lab. No. 461). Lava. Thick flow on ashy material, little port, east side of Rudha Dearg, 1 m. west of Lochaline; Morven. Basalt, p. 137. Anal. F. R. Ennos.

C. (S11727) [NM 337 993], Lab. No. 184). Lava. Orval; Rum. Basalt, quoted from A. Harker, Geology of the Small Isles of Inverness-shire, 1908, p. 57. Anal. W. Pollard.

D. (S8185) [NG 42 28], Lab. No. 21). Lava. Drynoch; Skye. Basalt, quoted from W. Pollard, Summary of Progress of Geol. Surv. for 1899, p. 174; see also A. Harker, Tertiary Igneous Rocks of Skye, p. 31. Anal. W. Pollard.

E. (S8062) [NG 468 256], Lab. No. 79). Cone-Sheet. Cuillins; Skye. Dolerite, emended analysis quoted from A. Harker, Tertiary Igneous Rocks of Skye, p. 370. Anal. W. Pollard.

(Table 2) Non-Porphyritic Central Magma-Type of Figure 2

Tholeiite Salen Type Basalt Staffa Type Basalt Staffa Type Basalt Staffa Type Basalt Compact Central Type Basalt Compact Central Type Tholeiite Brunton Type Quartz-Dolerite and Tholeiite Talaidh Type Quartz-Dolerite and Tholeiite Talaidh Type
I II III A IV V VI VII VIII IX
SiO2 47.35 47. 80 49.76 52.13 50. 54 53.78 51..53 51.63 5276 53.97
TiO2 1.75 — 0.94 — 2.80 2.28 1.57 2.00 3.25 1.24
Al2O3 13.90 14.80 14.42 14.87 12.86 12.69 11.05 11.77 11.95 14.65
Fe2O3 5.87 — 3.95 — 4.13 3.44 2.73 3.23 4.86 3.62
FeO 8.96 13.08 7.77 11.40 8.75 8.94 10.08 10.47 9.92 6.32
MnO 0.23 0.09 0.20 0.32 0.32 0.53 0.45 0.35 0.18 0.30
(Co, Ni)O nt. fd. — nt. fd. 1 0.06 nt. fd. nt. fd. 0.04 — nt. fd.
MgO 5.97 6.84 5.30 1 6.46 4.63 2.58 5.21 5.02 3.77 4.49
CaO 10.65 12.89 10.22 10.56 8.74 6.36 9.68 9.34 7.14 7.98
BaO — — 0.04 — nt. fd. 0.09 nt. fd. 0.03 — 0.04
Na2O 2.73 2.48 2.49 2.60 2.89 2.74 3.48 2.90 2.36 2.54
K2O 0.54 0.86 1.83 0.69 1.43 2.27 0.86 0.91 1.74 P52
LiO2 — — tr. — nt. fd. nt. fd. tr. nt. fd. — tr.
H2O+105° 1.16 1.41 1.03 1.9 2.25 2.19 1.26 1.40 1.95 0.94
H2O at 105° 1.04 2.04 0.17 1.19 0.71 0.68 0.56 1.92
P2O5 0 24 — 0.21 — 0.34 0.55 0.22 0.29 0.24 0.27
CO2 0.32 — 0.06 — 0.33 0.08 0.08 0.11 0.18 0.51
FeS2 — 0.04 — nt. fd. 0.42 0.26 0.08 — 0.09
S 0.23 — — — — — — — 0 18
100.94 100.25 100.30 100.22 100.24 100.13 100.07 100.27 100.44 100.40
Spec. grav. 2.96 — 2.72 — 2.90 2.68 2.93 2.95 2.91 2.831
I. (S16808) [NM 5593 4670], Lab. No. 407). Dyke. Shore ¼ mile S.S.E. of Kintallen and 2 miles N.N.W. of Salen; Mull. Tholeiite, Salen Type, p. 371. Anal. F. R. Ennos.

II. Lava. Staffs,. Basalt, staffa type. Anal. A. Streng, quoted from Pogg. Ann. vol. xc., 1853, p. 114.

III. (S20581) [NM 4025 2793], Lab. No. 669). Lava, which encloses Macculloch's Tree. Rudha na h-Uamha; Mull. Basalt, Staffa Type, p. 145, Anal. E. G. Radley,

A. Lava. Giant's Causeway; Ireland. Basalt, Staffa Type. Anal. A. Streng, quoted from Pogg. Ann., vol. xc., 1853, p. 114.

IV. (S18474) [NM 6309 3205], Lab. No. 448). Lava. Monadh Beag, stream-junction 1000 yards N. of Ishriff; Mull. Basalt, Compact Central Type, p. 149. Anal. E. G. Radley.

V. (S14824) [NM 5819 3928], Lab. No. 369). Lava. 1 mile N.E.of Loch Bà, 2 miles E. of Gruline House; Mull. Basalt, Compact Central Type, p. 149. Anal. E. G. Radley.

VI. (S16810) [NM 5541 4837], Lab. No. 406). Dyke. Shore, ¼ mile E. of Arla, and 5½ miles S.E. of Tobermory; Mull. Tholeiite, Brunton Type, p. 372. Anal. E. G. Radley.

VII. (S16809) [NM 5592 4755], Lab. No. 411). Dyke. Shore mile ¼ N. of Kintallen, and 3 miles N.N.W. of Salen ; Mull, Tholeiite, Brunton Type, p. 372. Anal. E. G. Radley.

VIII. (S18967) [NM 6869 3105], Lab. No. 444). Cone-Sheet. 70 yards S. of summit, Cruachan Dearg ; Mull. Quartz-Dolerite, Talaidh Type, p. 301. Anal. F. R. Ennos,

IX. (S17170) [NM 5238 2024], Lab. No. 432). Basic Margin, Composite Sill. Rudh 'a 'Chromain ; Mull. Tholeiite, Talaidh Type, pp. 285, 286. Anal. E. G. Radley.

(Table 3) Intermediate to Subacid Magma-Type of (Figure 2)

Craignurite (basic) Leidleite Leidleite Inninmorite Inninmorite InninmoriteCraignurite (acid)
I. II. III. IV. V. VI.
SiO2 55.82 59.21 61.69 62.37 64.13 66.27 SiO2
TiO2 1.62 1.06 1.00 1.06 1.19 0.87 TiO2
Al2O3 11.47 14.06 14.43 12.04 13.15 11.92 Al2O3
Fe2O3 3.68 2.66 1.23 1.87 1.08 3.09 Fe2O3
FeO 7.66 4.87 5.86 5.81 6.31 3.18 FeO
MnO 0.40 0.24 0.30 0.24 027 0.31 MnO
(Co,Ni)O 0.04 nt. fd. nt. fd. nt. fd. nt. fd. nt. fd. (Co,Ni)O
MgO 4.08 3.71 2.81 0.97 1.08 1.44 MgO
CaO 7.88 5.95 4.97 3 51 3 62 3.30 CaO
BaO 0.03 0.03 0.04 0.07 0.09 nt. fd. BaO
Na2O 2.58 2.06 3.20 3.47 3.64 2.89 Na2O
K2O 2.00 2.83 1.72 2.34 2.32 4.03 K2O
Li2O tr. nt. fd. nt. fd. nt ftl. nt. fd. tr. Li2O
H2O + 105° 1.88 1.49 2.32 5.54 2.71 1.51 H2O-1–105°
H2O at 105° 0.66 2.06 0.25 0.44 0.36 0.78 H2O at 105°
P2O6 0.23 0.20 0.24 0.30 0.31 0.17 P2O6
CO2 0.08 — — — — 0.53 CO2
FeS2 0.09 nt. fd. nt. fd. nt fd. nt. fd. nt. fd. FeS2
Cl. nt. fd. 002 — — — Cl.
100.18 100.43 100.08 100.03 100.26 100.29
Spec. grav. 2.88 2.61 2.64 2.50 2.57 2.65 Spec. grav.
I. (S16800) [NM 6857 3750], Lab. No. 412). Cone-Sheet. Allt an Dubh-choire, 1220 yards above junction with Scallastle River; Mull. Craignurite (basic), p. 226. Anal. E. G. Radley.

II. (S15997, Lab. No. 385). Sill, stony margin of III. ¼ mile N.N.E. of Mullach Glac an t-Sneachda (Loc. 1, (Figure 43), p. 261); Mull. Stony Leidleite, p. 281. Quoted from E. M. Anderson and E. G. Radley, Quart Journ, Geol Soc., vol. lxxi, p. 212. Anal. E. G. Radley.

III. (S15996) [NM 5021 2337], Lab. No. 384). Sill, glassy centre of II. Glassy Leidleite, or Leidleite-pitchstone, p. 281. Quoted from E. M. Anderson and F. G. Radley, ibid, p. 212. Anal. E. G. Radley.

IV. (S15989) [NM 5077 2552], Lab. No. 386). Sheet. Near head of stream from Tòm a' Choilich, ½ mile S.W. of Pennyghael (Loc. 4, (Figure 43), p. 261); Mull. Exceptionally glassy Inninmorite, or Inninmorite-Pitchstone, p. 283. Quoted from E. M. Anderson and E. G. Radley, ibid, p. 212. Anal. E. G. Radley.

V. (S15990) [NM 5176 2404], Lab. No. 387). Sheet. 3/16 mile S.W. of Trig. Station on Beinn an Lochain (Loc. 5, (Figure 43), p. 261); Mull. Fairly glassy Inninmorite or Inninmorite-Pitchstone, p. 284. Quoted from E. M. Anderson and E G. Radley, ibid, p. 212. Anal. E. G. Radley.

VI. (S16802) [NM 6903 3752], Lab. No. 413). Cone-Sheet. Allt an Dubh-choire, 630 yards above junction with Scallastle River; Mull. Craignurite (acid), p. 225. Anal. E. G. Radley.

(Table 4) Acid Magma-type of Figure 2

I II III IV V
SiO2 70.70 71.30 72.66 73.12 73.32 SiO2
TiO2 1.27 0.58 0.34 0.39 0.51 TiO2
Al2O3 11.78 11.24 12.00 12.44 12.25 Al2O3
Fe2O3 1.32 1.80 2.03 2.09 2.77 Fe2O3
FeO 3.45 2.84 2.04 1.65 2.20 FeO
MnO 0.07 0.31 0.18 0.17 0.12 MnO
(Co,Ni)O — nt. fd. nt. id. nt. fd. nt. fd. (Co,Ni)O
MgO 0.53 0.61 0.07 0.14 0.11 MgO
CaO 1.30 1.56 1.25 0.88 1.65 CaO
BaO — 0.07 0.12 nt. fd. 0.09 BaO
Na2O 2.48 3.44 3.26 3.90 3.92 Na2O
K2O 4.71 4.66 5.26 4.67 2.34 K2O
Li2O — ? tr. nt. fd. nt. fd. nt. fd. Li2O
H2O+105° 1.14 1.04 0.47 0.24 0.35 H2O+105°
H2O at 105° 0.50 0.39 0.22 0.25 0.35 H2O at 105°
P2O5 0.26 0.22 0.04 0.09 0.10 P2O5
CO2 0.51 — 0.24 0.05 0.06 CO2
FeS2 nt. fd. nt. fd. nt. fd. nt. fd. FeS2
S 0.08 — — — — S
100.10 100.06 100.18 100.08 100.14
Spec. grav. 2.58 2.53 2.61i 2.57 2.66 Spec. grav.
I. (S18464) [NM 5361 2259], Lab. No. 443). Sill. S. of Coire Buidhe, between 800 and 900 foot contours, about ½ mile N. of Carsaig; Mull. Felsite allied to inninmorite, p. 286. Anal. F. R. Ennos.

II. (S16803) [NM 7167 3731], Lab. No. 394). Cone-Sheet. Craignure Bay, shore 50 yards N.N.W. of U.F.C. Manse; Mull. Fine Granophyre allied to craignurite, p. 226. Anal. E. G. Radley.

III. (S14825) [NM 5551 3738], Lab. No. 370). Loch Bà Ring-Dyke. Top of deep gorge ¾ mile N. of E. of Summit of Beinn a' Ghràig; Mull. Rhyolite, p. 347. Anal. E. G. Radley.

IV. (S14843) [NM 5497 3843], Lab. 372). Beinn a' Ghràig Ring-Dyke. Benmore Lodge, Loch Bà; Mull. Granophyre, p. 347. Anal. E. G. Radley.

V. (S14841) [NM 5427 3847], Lab. No. 371). Knock Ring-Dyke. Beinn Bheag, ¼ mile S. of Knock; Mull. Granophyre, p. 349. Anal. E. G. Radley.

(Table 5) Allivalite-Eucrite Magma Series of Figure 3

Eucrite I. B
Allivalite A Eucrite I. Eucrite B
SiO2 42.20 46.66 48.05 SiO2
TiO 0.09 0.47 0.49 TiO
Al2O2 17.56 16.71 15.35 Al2O2
Cr2O2 0.06 — 0.14 Cr2O2
Fe2O2 1.20 2.69 1.86 Fe2O2
FeO 6.33 5.87 7.53 FeO
MnO 0.18 0.12 0.28 MnO
(Co, Ni)O 0.13 — 0.11 (Co, Ni)O
CuO 0.04 — 0.05 CuO
MgO 20.38 12.36 12.53 MgO
CaO 9.61 12.57 11.02 CaO
Na2O 1.11 1.16 1.26 Na2O
K2O 0.11 0.27 0.19 K2O
Li2O — nt. fd. — Li2O
H2O + 105° 1.13 1.24 0.45 H2O + 105°
H2O at 105° 0.06 0.13 0.15 H2O at 105°
P2O5 — 0.13 — P2O5
CO2 tr. 0.18 0.44 CO2
S 0.02 nt. fd. 0.20 S
100.21 100.56 100.10
Spec. grav. 2.96 2.97 2.95 Spec. gray.
A. (S10464) [NM 395 962], Lab. No. 120). Major Intrusion. Allival; Rum. Allivalite, quoted from A. Harker, Geology of the Small Isles of Inverness-shire, 1908, p. 80. Anal. W. Pollard.

I. (S19069) [NM 606 268], Lab. No. 459). Major Intrusion. About 500 yards S.E. of summit of Ben Buie; Mull. Eucrite, p. 250. Anal. F. It. Ennos.

B. (S10471) [NM 400 960], Lab No. 123). Major Intrusion. Allt Màr na h-Uamha; Rum. Eucrite, quoted from A. Harker, Geology of the Small Isles of Inverness-shire, 1908, p. 98. Anal. W. Pollard.

(Table 6) Porphyritic Central Magma-Type of Figure 3

I. A B II. III. IV. V.
SiO2 45.54 46.39 47.28 48.34 47.24 47.49 48.51 SiO2
TiO2 1.06 0.26 0.28 0.95 1.46 0.93 1.46 TiO2
Al2O3 23.39 26.34 21.11 20.10 18.55 21.46 19.44 Al2O3
Cr2O — tr. — — — — — Cr2O
Fe2O3 1.98 2.02 3.52 11.97 6.02 1.72 5.66 Fe2O3
FeO 6.98 3.15 3.91 6.62 4.06 4.80 4.00 FeO
MnO 0.27 0.14 0.15 0.32 0.31 0.15 0.23 MnO
(Co,Ni)O nt. fd 0.05 0.04 0.04 (Co,Ni)O
MgO 4.60 4.82 8.06 5.49 5.24 4.59 5.12 MgO
CaO 11.82 15.29 13.42 13.16 11.2 13.24 12.03 CaO
BaO 0.10 nt. fd nt. fd. nt. fd. BaO
Na2O 2.50 1.63 1.52 1.66 2.42 2.17 2.53 Na2O
K2O 0.44 0.20 0.29 0.98 0.15 0.42 0.25 K2O
Li2O — — — nt. fd. nt. fd nt. fd. nt. fd. Li2O
H2O -F 105° 0.72 0.48 0.53 0.44 2.24 2.54 0.48 H2O -F 105°
H2O at 105° 0.62 0.10 0.13 0.02 0.21 0.17 0.04 H2O at 105°
P2O 0.13 tr. tr. 0.04 0.26 0.43 0.16 P2O
CO2 — — — 0.11 0.19 0.08 0.09 CO2
FeS2 — — — nt. fd. nt. fd. nt fd. nt. fd. FeS2
100.05 100.82 100.20 100.30 100.12 100.23 100.04 SiO2
Spec. grav. 2.85 2.85 2.90 2.93 2.85 2.82 2.93 TiO2
I. (S15994) [NM 5356 2253], Lab. No. 389). Sill. Hillside between two streams S. of Coire Buidhe; Mull. Small-felspar dolerite, p. 285. Anal. E. G. Radley.

A. (S8043) [NG 481 232], Lab. No. 18). Major Intrusion, Cuillins. Sligachan River; Skye. Olivine-gabbro, quoted from Harker, Tertiary igneous rocks of Skye; 1904, p. 103. Anal. W. Pollard.

B. (S8194) [NG 449 242], Lab. No. 19). Major Intrusion, Cuillins. Coir 'a 'Mhadaidh; Skye. Olivine-gabbro, quoted from Harker, ibid. p. 103. Anal. W. Pollard.

II. (S14846) [NM 5959 3684], Lab. No. 373). Major Intrusion, Beinn na Duatharach. 5/8 mile N.N.W. of summit of B. na Duatharach; Mull. Olivine-gabbro. Anal. E. G. Radley.

III. (S18469) [NM 5640 2847], Lab. No. 445). Lava. ½ mile S.S.W. of Derrynaculen; Mull. Basalt, Porphyritic Central Type, p. 148. Anal. E. G. Radley.

IV. (S18472) [NM 5960 3011], Lab. No. 447). Pillow-lava. ¼ mile slightly E. of S. of cairn on Cruach Choireadail; Mull. Basalt, Porphyritic Central Type, p. 150. Anal. E. O. Radley.

V. (S18471) [NM 5757 2907], Lab No. 446). Lava. 3/8 a mile N.E. of cairn on Cruach Doire nan Guilean, west side of a little lochan; Mull. Basalt, Porphyritic Central Type, p. 148, Anal.. E. G. Radley.

(Table 7) Alkaline Magma-Series of Figure 4

Mugearite Mugearite Mugearite Syenite Trachyte Trachyte
A B C I II III IV
SiO2 49.24 49.92 50.70 55.76 58.81 60.13 63.12 SiO2
TiO2 1.84 2.04 1.89 1.78 0.76 0.73 0.51 TiO2
AL2O3 15.84 12.83 14.60 16.55 14.81 16.53 15.44 AL2O3
Cr2O3 tr. tr. — — — — — Cr2O3
V2O3 0.04 — — — — — V2O3
Fe2O5 4.09 6.96 5.23 3.10 4.58 2.86 1.73 Fe2O5
FeO 7.18 6.21 7.68 6.02 4.21 2.55 3.53 FeO
MnO 0.29 0.52 0.42 0.22 0.27 0.46 0.27 MnO
(Co,Ni)O tr. 0.03 tr. nt. fd. nt. fd. nt. fd. nt fd. (Co,Ni)O
MgO 3.02 3.78 4.15 1.08 0.80 1.20 0.62 MgO
CaO 5.26 7.25 7.20 3.23 2.33 1.61 1.31 CaO
BaO 0.09 0.09 0.08 0.07 0.03 0.11 nt. fd. BaO
SrO tr. tr. tr. — — — — SrO
Na2O 5.21 3.72 3.71 4.28 5.60 8.06 5.81 Na2O
K2O 2.10 1.73 1.33 3.87 4.96 3.99 5.36 K2O
Li2O tr. ? tr. tr. nt. fd. tr. nt. fd. Li2O
H2O+105.° 1.61 1.05 1.15 0.95 0.82 0.97 0.44 H2O+105.°
H2O at 105° 1.08 3.58 2.08 0.80 2.00 0.55 0.14 H2O at 105°
P2O5 1.47 0.45 0.49 0.40 0.20 0.57 0.25 P2O5
CO2 — nt. fd. nt. fd. 0.03 — — 1.89 CO2
FeS2 — — — nt. fd. nt. fd. nt. nt. fd. FeS2
S 0.03 1 tr. nt. fd. — — — — S
F 0.18 — — — — — — F
100.46* 100.20 100.71 100.14 100.18 100.32 100.42
Spec. grav. 2.79 — — 2.67 2.64 2.51 2.89 Spec. grav.
A. (S8732) [NG 437 366], Lab, No. 80). Sill. Druim na Criche; Skye. Mugearite, quoted from A. Harker, Tertiary Igneous Rocks of Skye, 1904, p. 263. Anal. W. Pollard. *The total is 100.53 – 0.07 (oxygen equivalent of 0.18 fluorine).

B. (S11731) [NG 270 050], Lab. No. 179). Sill. Eilean a Bhaird; Canna. Doleritic Mugearite, quoted from A. Harker, Geology of the Small Isles of Inverness-shire, 1908, p. 130. Anal. W. Pollard.

C. (S11732) [NM 340 999], Lab. No. 186). Sill. Pass S. of Fionn-Chrò; Rum. Doleritic Mugearite, quoted from A. Harker, Geology of the Small Isles of Inverness-shire, p. 130. Anal. E. G. Radley.

I. (S20582) [NM 5364 2832], Lab. No. 670). Lava of Ben More horizon. Below road, 290 yards E. of Kinloch Hotel; Mull.: Mugearite, p. 144. Anal. E. G. Radley.

II. (S15991) [NM 5463 2063], Lab. No, 388). Intrusion. Gamhnach Mhòr, Carsaig Bay; Syenite, p. 189. Anal. E. G. Radley.

III. (S15753) [NM 5475 5022], Lab. No. 393). Plug in Ardnacross Vent. Shore mile W. of Rudh' an t-Sean-Chaisteil; between Salen and Tobermory; Mull. Trachyte, p. 192. Anal. E. O. Radley.

IV. (S14821) [NM 5429 3866] [NM 5429 3866]a, Lab. No. 368). Plug in Vent. Bràigh a' Choir' Mhòr., W. of Salen; Mull, Trachyte, p. 191. Anal. E. G. Radley.

(Table 8) Differentiation — Column of Glen More Ring-Dyke as exposed in Cruach Choireadail and Coir' An T-Sailein, 2½ miles apart

Cruach Choireadail (Figure 54), p. 322 Cruach Choireadail (Figure 54), p. 322 Cruach Choireadail (Figure 54), p. 322 Coir' an t-Sailein.
I II. III IV V VI
SiO2 49.90 51.32 56.22 68.12 50.04 57.18
TiO2 2.56 0.98 2.74 1.26 2.56 3.25
Al2O3 12.70 13.96 12.45 13.08 13.32 10.75
Fe2O 4.20 2.48 3.09 1.02 4.71 4.96
FeO 7.88 7.10 7.58 3.26 8.07 6.24
MnO 0.36 0.34 0.43 0.39 0.33 0.32
(Co, Ni)O nt. fd. nt. fd. nt. fd. nt. fd. nt. fd. nt. fd.
MgO 5.88 5.78 2.78 0.71 5.01 2.15
CaO 10.39 11.51 5.93 1.81 10.02 5.73
BaO nt. fd, nt. fd. 0.04 0.04 nt. fd. 0.06
Na2O 2.86 3.50 3.82 4.15 3.28 4.62
K2O 0.95 1.16 2.67 4.47 1.08 2.67
Li2O nt. fd. nt. fd. nt. fd. nt. fd. tr, tr.
H2O+105° 1.65 1.27 1.35 1.16 1.45 1.31
H2O at 105° 0.67 0.36 0.44 0.40 0.27 0.33
P2O5 0.20 0.24 0.50 0.22 0.28 0.46
CO2 0.09 0.09 0.05 0.06 0.08 0.08
FeS2 nt. fd. nt. fd. nt. fd. nt. fd. nt. fd. nt. fd.
100.29 100.09 100.09 100.15 100.50 100.11
Spec. grav. 2.95 2.91 2.77 2.55 2.97 2.71
I.-IV. Ascending sequence, Cruach Choireadail.

I. (S18463) [NM 6027 2939], Lab. No. 442). Glen More Ring-Dyke. ½ mile W.N. W. of Creag na h-Iolaire, Glen More; Mull. Quartz-Gabbro, p. 328. Anal. E. G. Radley.

II. (S18462) [NM 5990 2974], Lab. No. 441). Glen More Ring-Dyke. Fully ½ mile S.S.E. of cairn on Cruach Choireadail; Mull. Quartz-Gabbro, p. 328. Anal. E. G. Radley.

III. (S18461) [NM 5967 3006], Lab. No. 440). Glen More Ring-Dyke. Fully ¼ mile S.S.E. of cairn on Cruach Choireadail; Mull. Allied to Craignurite, p. 328. Anal. E. G. Radley.

IV. (S18460) [NM 5959 3044], Lab. No. 439). Glen More Ring-Dyke. 130 yards E.S.E. of cairn on Cruach Choireadail; Mull. Allied to acid Craignurite, p. 328. Anal. E. G. Radley.

V. and VI. Ascending Sequence Coir' an t-Sailein.

V. (S18455) [NM 5654 3251], Lab. No. 437). Glen More Ring-Dyke. Rather more than ½ mile W. N. W. of Corra-bheinn; Mull. Quartz-Gabbro, p. 328. Anal. E. G. Radley.

VI (S18456) [NM 5687 3206], Lab. No 438). Glen More Ring-Dyke. Fully ¼ mile W.S.W. of Corra-bheinn; Mull. Allied to Craignurite, p. 328. Anal. E. G. Radley.

(Table 9) In British Museum Students' Index, Tobermorite is listed as a synonym of Gyrolite.

Amygdale Minerals
Phenocrysts Outside Pneumatlysis Limit Inside Pneumatlysis Limit Inside Contact Zone Mudstone Xenoliths and enclosed Spinel
I. II. III. IV. V. VI. VII. VIII. IX. X. XI. XII. XIIa XIII XIV XV XVI XVII XVIII
SiO2 49.72 50.80 53.74 53.41 52.95 53.39 48.91 46.51 46.62 46.75 46.21 46.10 45.9 38.69 37.66 39.26 49.74 38.67 0.77 SiO2
TiO2 0.85 — — — — — — — — — — nt. fd. — 0.12 0.12 1.33 1.49 0.90 0.50 TiO2
Al2O3 0.90 31.51 0.82 1.76 1.71 — 0.11 2.40 3.9 24.82 27.00 25.05 26.0 28.54 21.84 27.34 34.99 37.27 60.84 Al2O3
Fe2O3 1.72 — — — — — — 1.14 0.66 — — — — 6.97 4.07 1.57 1.53 2.78 4.26 Fe2O3
FeO 27.77 — — — — — 2.97 1.85 1.08 — — 0.55 — 0.22 0.34 17.18 0.34 5.07 24.00 FeO
MnO 0.98 — — — — — 2.27 — — — — nt. fd. — 0.29 0.53 0.13 0.15 0.17 0.15 MnO
(Co,Ni)O nt. fd. — — — — — — — — — — nt. fd. — nt. fd. nt. fd. 0.04 nt. fd. nt. fd. nt. fd. (Co,Ni)O
MgO 12.69 — — — — — 0.56 0.47 — — — 0.32 — 0.49 0.45 0.34 0.66 2.35 9.37 MgO
CaO 3.80 12.83 31.19 31.69 31.48 33.41 40.39 33.40 33.98 14.20 13.45 14.17 14.3 23.78 33.06 0.74 0.88 4.65 0.36 CaO
BaO — — — — — — — — — — — — — — — nt. fd. nt. fd. — — BaO
Na2O 0.23 3.96 9.94 8.11 8.04 8.8 0.22 0.36 0.89 0.89 — tr. — tr. 1.17 1.08 3.76 3.63 —

—

 Na2O
K2O 0.12 tr. nt. fd. 2.42 2.45 — 1.16 1.45 0.57 — — 0.03 — 0.03 0.75 2.05 1.72 3.01 — K2O
Li2O tr. — — — — — — — — — — nt. fd. — tr. 0.20 nt. fd. tr. nt. fd. — Li2O
H2O+105° 1.27 0.52 3.38 3.66 4.07 4.46 4.17 12.61 12.11 13.64 13.78 13.78 13.8 0.99 nt. fd. 7.20 3.44 1.63 0:14 H2O+105°
H2O at 105° 0.08 — 0.6 — — — — — — — — 013 — 0.09 — 1.44 0.61 0.22 nt. fd. H2O at 105°
P2O5 — — — — — — — — — — — — — — — 0.34 0.86 — — P2O5
CO2 — — — — — — — — — — — — — — — — 0.04 — — CO2
FeS2 — — — — — — — — — — — — — — nt. fd. nt. fd. 1— — FeS2
100.13 99.65 99.67 101.05 100.67 100.06 100.76 100.19 99.81 98.80 100.44 100.13 100.0 100.21 100.19 100.04 100.21 100.35 100.39
Spec. grav. — — — — — — 2.605 — 2.423 — — 2.285 — 3.488 3.61 — 2.65 2.91 3.837 Spec. grav.
I. Uniaxial Augite. II. Labradorite. III.-VI. Pectolite. VII. Xonotlite. VIII, IX. Tobermorite.<ref>In British Museum Students' Index, Tobermorite is listed as a synonym of Gyrolite</ref> X.—XII. Scolecite. XIII. Pink Epidote. XIV. Garnet. XV. Basal Mudstone (altered). XVI. Uncontaminated argillaceous xenolith. XVII. Contaminated argillaceous xenolith. XVIII. Dark-green Spinel.

Explanation of (Table 9).

Phenocryst in Inninmorite (Chapter 25)

I. Uniaxial augite, lab. No. 402, separated from V of Table 3 Anal. E. G. Radley, quoted from A. F. Hallimond, Min. Mag., vol. xvii., 1914, p. 99.

Phenocryst in basalt (chapter 34)

II. Labradorite (? from N. W. Dyke, p. 358). S.E. of Tobermory; Mull. Collected by J. W. Judd, Quart. Journ. Geol. Soc., vol. xlii, 1886, p. 71. Anal. T. H Holland, Min. Mag., vol. viii., 1889, p. 156.

Amygdale-minerals, collected outside limit of pneumatolysis of Plate 3 (Chapters 5 AND 10)

Pectolite. Dearg Sgeir, N.W. of mouth of Loch Scridain; Mull. Quoted from M. F. Heddle, Trans. Geol. Soc. Glasgow, vol. ix., 1892, p. 244. Anal. Stuart Thomson.

IV. Pectolite. Same locality, M. F. Heddle, op. cit., p. 245. Anal. Stuart Thomson.

V. Pectolite. Same locality, M. F. Heddle, op. cit., p. 245. Anal. Stuart Thomson.

VI. Pectolite.. Same locality, M. F. Heddle, op. cit., p. 245. Anal. C. Robertson.

VII. Xonotlite. Kilfinichen, Loch Scridain; Mull. Anal. M. F. Peddle, quoted from Min. Mag., vol. v., 1884, p. 4.

VIII. Tobermorite. North of Tobermory Pier; Mull. Anal. M. F. Heddle, quoted from Min,. Mag., vol. iv., 1882, p. 119.

IX. Tobermorite. Near Lighthouse, N. of Tobermory; Mull. Anal. M. F. Heddle, quoted from Min. Mag., vol. iv., 1882, p. 120.

X. Scolecite. Staffa. Quoted from M. F. Heddle, Mineralogy of Scotland, 1901, vol. ii , p. 106. Anal. Fuchs & Gehlen, Schweigger's Journal, vol, xviii., 1816, g. 13.

Amygdale-minerals, collected within limit of pneumatolysis of Plate 3, but not contact-altered (chapter 10)

XI. Scolecite. Near Beinn na Croise, S.E. of Loch Scridain (locality quoted from Heddle's Mineralogy, p. 107); Mull. Anal. A. J. Scott, Ed. New. Phil. Journ., vol. liii., 1852, p. 282.

XII. Scolecite, Lab. No. 403. North-east slope of An Gearna; Mull. Quoted from W. F. P. M'Lintock, Trans: Roy. Soc. Edin., vol. li., 1917, p. 5. Anal. E. G. Radley.

XIIa. Scolecite, calculated for formula CaAl2Si3O10+3H2O.

Amygdale-minerals, collected within contact-zone of Beinn a Ghràig granophyre (chapter 10)

XIII. Pink Epidote, Lab. No. 404. N.B. slope of An Gearna; Mull. Quoted from W. F. P. M'Lintock, op. cit., p. 6. Anal. H. G. Radley.

XIV. Garnet, lab. No. 416. N.E. slope of An Gearna; Mull. Quoted from W. F. P. M'Lintock, op cit., p. 8. Anal. E. G. Radley.

Basal mudstone collected within limit of pneumatolysis of Plate 3

XV. Mudstone, lab. No. 395. At lava-base, 1 mile S. of entrance to Loch Don; Mull. Anal. E. G. Radley, pp. 58, 59.

Loch Scridain Xenoliths (chapter 24)

XVI. Silliminite-Buchite, Lab. No. 431, with 0.48 per cent. of sapphire. Uncontaminated portion of Xenolith in IX., (Table 2), Nuns' Pass, Carsaig; Mull. Quoted from H.H. Thomas, Quart. Journ. Geol. Soc., vol. laxviii., 1922, p. 236. Anal. E. G. Radley.

XVII. (16612, Lab. No. 396), Contaminated xenolith, with basic plagioclase, mullite, sapphire (1.45 per cent), and spinel, in same exposure as xvi. Quoted from H. H. Thomas, op. cit., p. 236. Anal. E. G. Radley.

XVIII. Dark-green Spinel, Lab. No. 397, between magnesian pleonaste and ferrous hercynite. Separated from XVII. Quoted from H. H. Thomas, op. cit., p. 247. Anal. E. G. Radley.

(Table 10)—Synopsis of Mull basalts microscopically examined from 1-inch map, Sheet 44

Ornament employed in Plate 3 Number of Slides Examined Number of Slides Examined. Number of Slides with—
District Plateau Types Central Types Olivine fresh Olivine all decomposed
Area 1 Plateau 16 1 15 2
Area 2 Plateau 8 1 4 5
3 6 Nil 5 1
4 8 Nil 8 Nil
4a 4 Nil 2 22
5 Central Nil Nil Nil Nil
5 Plateau 60 60 Nil 60
6 Central 2 36 Nil 3
6 Plateau 38 6 Nil 42
7 Central 2 21 Nil 5
7 Plateau 17 1 Nil 18
8 Central 1 5 Nil 1
8 Plateau 107 5 Nil 112
9 Central Nil 2 Nil Nil
9 Plateau 52 8 Nil 62
10 Nil 74 Nil 33
Sheet 44 (inclusive) Central 5 139
Sheet 44 (inclusive) Plateau 316 23
Areas 1.4A lie outside the Pneumatolysis Limit. They supply 44 slides, showing olivine (or its pseudomorphs); and in 34 cases the mineral is fresh. Areas 510 lie inside the Pneumatolysis Limit. They supply 336 slides, showing pseudomorphs after olivine, and none in which fresh olivine has been noted.

None of the sliced specimens mentioned was collected with a view to determining the condition of the olivine.

(Table 11) Water of augite-andesites

Ia Ib IIa IIb IIIa IIIb IV V
SiO2 61.69 59.21 62.37 64.13 SiO2
H2O+105° 2.36 1.54 2.38 1.56 2.44 0.93 5.54 2.71 H2O+105°
H2O at 105° 0.25 2.05 0.45 1.34 0.38 1.64 0.44 0.36 H2O at 105°
Cl 0.02 nt. fd. Cl
Spec. grav. 2.64 2.61 2.82 2.17 2.89 2.71 2.50 2.57 Spec. grav.
Analyses by E. G. Radley, quoted from E. M. Anderson and E. G. Radley, Quart. Journ. Geol. Soc., vol. lxxi., p. 212.

Ia, Ib (S15996) [NM 5021 2337] and (S15997) [NM 5021 2337]; Lab. Nos. 384, 385). Glassy (a) and stony (b) portions of Leidleite sill, ¼ mile N.N.E. of cairn on Mullach Glac an t'Sneachda. (Locality 1, (Figure 43); complete Anals. III. and II., (Table 3), p. 19).

IIa, IIb. (S17243) [NM 5018 2359] and (S17244) [NM 5018 2359]; Lab. Nos. 417, 418). Glassy (a) and stony (b) portions of Leidleite sill, 730 yds. N.N.E. of cairn on Mullach Glac an t'Sneachda. (Locality 2, (Figure 43))

IIIa, IIIb. (S17245) [NM 5057 2261] and (S17246) [NM 5057 2261]; Lab. Nos. 419, 420). Glassy (a) and stony (5) portions of Leidleite Sill, 1000 yds. S. E. of cairn on Mullach Glac an t'Sneachda. (Locality 3, (Figure 43))

IV (S15989) [NM 5077 2552]; Lab. No. 286). Extremely glassy Inninmorite sheet, near head of stream from Tòm a' Choilich. (Locality 4, (Figure 43); complete Anal. IV., (Table 3). p. 19)

V. (S15990) [NM 5176 2404]; Lab. No. 387). Fairly crystalline Inninmorite sheet with glassy base, 3/16 mile S.W. of Trig. Station on Beinn an Lochain. (Locality 5, (Figure 43); complete Anal. V. (Table 3), p. 19)