The Geological Society of Hong Kong 香港地質學會
Last updated: 23 March 2015
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Rock of the month

An uncommon piece of rock called Lithophysae (Figure 1) was discovered on the rock slope of somewhere in Sai Kung in New Territories. Lithiphysae is spherical to ellipsoidal in shape with radial or concentric cavity (Figure 2). It often occurs in siliceous or felsic volcanic rocks such as rhyolite, ignimbrite, rhyolitic lava, obsidian, perlite, tuff and pitchstone. The preliminary identification of the mineral in the lithophysae cavity discovered inSai Kung is either chalcedony or amorphous silica (Figure 3). If the cavity contains adequate space for mineral growing, it may have a chance to form quartz crystals as shown in Figure 4.

Our Society - GSHK
The Geological Society of Hong Kong is a non-profit organisation that attempts to promote geological and earth science studies within Hong Kong and the adjacent region. We organise local and overseas fieldtrips, as well as lectures. The Society publishes a journal (The Hong Kong Geologist) and bulletins dealing with a variety of earth science subjects.

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Whats New!

Field Trip to Nam Chung-Luk Keng
Date: 12 Apr. 2015 (Sun)
Assembly Time: 9:30 am (sharp)
Assembly Point: Green mini bus terminus off Fanling MTR station (Exit C)
Hike Distance: about 10 km
Estimated Time of Arrival: 4:00pm (Luk Keng minibus terminus)
Rating: Moderate to Difficult
Trip Leader: Leung Kar Fai

CPD Hours: 4 hours Application closing:05 Apr.15
For registration, Please fill out the form

Ir. Prof. Philip CHUNG Technical Seminar on (19 March 2015) powerpoint is ready for downloading

The 8th World Chinese Geological Congress (8th WCGC) - Taiwan

The 2nd circular

Organiser: The Institute of Earth Sciences (IES) of Academia Sinica in Taipei, Taiwan and others (please refer to the circular)

Date: Shifted to June 15-21, 2015,

Registration will start in early 2015 and we will notify members once details are available

Venue: Taipei, Taiwan
Call for paper (Reply due date: 31.10.2014)
Please click here for
1. The 1st circular
2. The 2nd circular
2. The reply slip
Professor Oldrich Hungr Joint Technical Seminar on Non-textbook Flowslides in Fine-grained Colluvium (2 Dec. 2014) powerpoint is ready for your downloading

Denise TANG 2014 AGM talk powerpoint sharing"What happened in HK after the High Island super-eruption?"
Please click and download.