Sheth et al.: Palitana lavas and Eastern Saurashtra dykes, Deccan Traps
Electronic Supplementary Material: ESM_3
Field notes and samples
(Field party: Hetu Sheth, Pooja Kshirsagar, Badrealam Shaikh, assisted by Dipak Gosain)
December 2009
The Shatrunjay section, Palitana
Elevation of Shatrunjay mountain is 501 m according to Survey of India toposheet. Altimeter set to 490 m
outside summit temple complex. Samples collected on the way down.
PL1: Topmost flow, fine-grained aphyric, dark, basalt, outside temple complex. Altimeter set at 480 m.
This is at Rampol gate. 480 m
PL2: 470 m, compound flow exposure on left. Fresh, green, fine-grained, with phenocrysts of unknown
minerals. Few small samples. Photo of BA. 471 m
PL3: Just below here, also 470 m, is a different compound flow, well developed. Abundantly plagioclaseporphytic. Also some amygdules. Phenocrysts are all tiny (2-3 mm) but present throughout the rock.
Different from PL2. Photo of PVK. 469 m
PL4: Still ahead, 470 m yet, bouldery outcrops in situ. Trend E-W but not clearly a dyke. Greenish/grey,
weathered, black phenocrysts. Many amygdules in PL4 as well. Photo with BA. 465 m
PL5: Next outcrop at 450 m on left beside temple. Bouldery. Interesting and unusual. Partly spilitized
basalt? Distinct spotted appearance with large patches or clots of black basalt (2-3 cm) in a green matrix.
Like outcrops described by Sethna in the Daman area, and seen by me at in quarries at the base of
Pavagadh. 455 m
PL6: Bouldery outcrops are of rock like PL2, with peppery appearance. The spotted outcrops (PL5) are of
smaller boulders next to these. PL6 is fresh, with small peppery black grains throughout. Both are at 450455 m. 450 m
Next outcrops on left at 410 m. Highly weathered flow. Not sampled. Just above vishram sthan (resting
place)/Padmavati temple.
PL7: Again at 390 m, on left. Highly weathered. Spheroids, but sampled. Again peppery appearance.
Elevation of PL7 is 380 m. 380 m
PL8: On right, highly weathered in situ outcrop at 370 m. Like exfoliation-related layering. Photo with
PVK. Contains fresh units ahead beside weathered ones. Extensively zeolitized and amygdaloidal. PL8,
370 m, from fresher unit. Weathered but useful. 370 m
PL9: 355 m. Seems to continue, but petrography is different. Compound flow, highly weathered, with
fresher units. Light grey with strong peppery appearance. Do not know what this rock is. Nice specimen.
355 m
PL10: 335 m. Quite different, black, highly weathered flow with fresh parts. Aphyric fine-grained basalt.
Photo with No. 228 in Gujarati in white. 335 m
PL11: 310 m, again peppery. Weathered outcrops right of road. Fresh samples possible. Fine-grained and
also medium-grained. 310 m
PL12: Outcrops on right, 250 m. Amygdaloidal but reasonably fresh. Fine-grained aphyric. Contains
zeolites and unidentified black spots on surface. 250 m
PL13: 150-160 m. Right of another rest stop, outcrop of compound flows. Look weathered. Fine-grained,
aphyric basalt, sparse white plagioclase phenocrysts. 150 m
PL14: 90 m. Very near the base, possibly the last (lowest) in situ outcrop in the section, on this side.
Medium-grained, aphyric, fairly fresh. 90 m
PL15 and PL16, collected from face in a ravine on the southern side of the Shatrunjay mountain, 7 km from
Palitana town towards Hastagiri. Both below PL14.
PL15: Weathered and with spotty appearance. Highly weathered picrite? ~60 m
PL16: 10 m below PL15, uniform looking, lowermost exposed flow of the whole sequence. Nice view of
imposing mountain with summit temples. Did not venture further or stay longer, due to leopards reported
by locals. ~50 m
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The Eastern Saurashtra dykes
ESD1: Dyke N of Garibpura, in roadcut. Garibpura is 4 km E of Trapaj Bungalow Railway Station. This is
the northern dyke of a pair. Basalt, fine-grained, aphyric, with white zeolites. Trend N80 locally, ~E-W
overall. Width can’t be told. N80
ESD2: Dyke, a few km long, forming low ridge crossing road <1 km NW of Kukad and 6 km SE of Tansa.
Highly weathered and soil covered. Few outcrops. Collected some spheroids, fresh inside. Fine-grained
basalt. N75
ESD3: N80 dyke between Kukad and Tansa, 2 km SE of Tansa. Very weathered, small spheroids. Fresh
aphyric basalt inside. N80
ESD4: Very weathered dyke, very long (several km) crossing highway, exactly at Trapaj Bungalow RS. 4
km N of Trapaj. Fresh sample taken. Basalt, with sparse black pyroxene phenocrysts. N88
ESD5: Dyke 1 km S of Dihor, on the way to Samadhiala. Low ridge E of road, several km long. Spheroids
collected from top. Aphyric basalt. N65
ESD6: N290-N110 dyke 1.5 km N of Vavdi, on road to Ghogha, before Nathugarh. Whole low ridge in
soil except a solitary boulder of fresh aphyric basalt. N100
ESD7: E-W dyke 1.5 km SW of Valespur and ~4 km NE of ESD6. Forms soil-covered linear ridge with
several quite fresh boulders on top. Phyric basalt, with plagioclase phenocrysts. N88
ESD8: N100 dyke, just E of Nathugarh, very weathered, fresh spheroids taken. Fresh aphyric basalt. E-W
trend by map. N88
ESD9: Rhyolite dyke ridge N of and touching Devgana. Trends N-S. Rock is highly weathered and
silicified. Fine grained. N355
ESD10: Basalt dyke 3 km N of Varal and 2.5-3 km S of Tana. Low ridge. Highly amygdaloidal (zeolites
mostly) as well as porphyritic (yellowish white plagioclase laths 3-4 mm long). Longest dyke in the region?
12-13 km or more. Width unknown. N70
ESD11: Very fresh dolerite dyke, aphyric, 1 km S of Varal. Cuts through the split of the road to Ramgadh
and Dihor. N80-85 trend. Fresh quarried boulders on E side. N80
ESD12: Beautiful plagioclase-porphyritic dyke 1 km from Thorali and a few km SW of Varal. Forms the
lower part of a N80 dyke ridge which might be the same as ESD11. Multiple dyke? The upper, middle part
of this does look like ESD11. Medium-grained dolerite, joint blocks, fresh. Not sampled. Boulders of the
porphyritic type show local phenocryst accumulation, such that the rock trends towards a cumulate (with a
matrix). The whole rock is porphyritic to highly porphyritic. Phenocrysts are plagioclase and <1 cm long.
N80
ESD13: Dyke below Varal dispensary. Runs through village. Bouldery outcrops sampled after permission
from villagers. Very fresh, fine-grained basalt/dolerite, totally aphyric. Good samples. N60
ESD14: Long dyke between Vavdi and Bhawanipura. E-W trend. Roadcut through dyke, E of Vavdi, ~0.5
km. Very fresh dolerite, aphyric, sampled in roadcut boulder. Road is parallel to and beside the dyke. Most
of the dyke is soil-covered without outcrops. N90
ESD15: ~E-W (N85) dyke of fresh basalt, 1.5 km NW of Nagdhaniba on the way to Sartanpur. Outcrops
rare but cuts available on road (not useful) and on left. Quite fresh, aphyric, several km long. N85
(Came to Malnath temple (200 m elevation) in N-S hill range by road from Kobadi (7 km, on TalajaBhavnagar highway). The Suzlon windmills are at highest point (301 m, Trambak). Altimeter seems correct
– only 5 m below actual. Reset at Suzlon site.
ESD16: Dyke sampled in roadcut on way back/down. 250 m elevation, ~N70 trend, bouldery outcrop,
fresh spheroids sampled, fresh, tough, aphyric dolerite. Malnath temple visible in the valley below is N260
from here. N70
ESD17: Granophyre dyke 10 km from Palitana on road to Hastagiri. Outcrops on side of road towards
Shatrunjay mountain. Rock is red on weathered faces and also greenish, but white when fresh. Quartz
grains identifiable. Texture suggests not rhyolite but granophyre. Appears to be a dyke, no trend discernible.
Part of Eastern Saurashtra dykes, hence ESD17. N?
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