Tony Waltham: lecture presentations

The main source of gem-quality diamonds has switched from India to South Africa, and then to Botswana and Canada. Explosive kimberlite pipes carry diamonds up from their deep sources.

A journey through India reveals an amazing variety of beautiful and dramatic landscapes, from the backwaters of Kerala to the colours of Rajasthan and northwards to the grandeur of the Himalayas.

The western mountains of Saudi Arabia have dramatic desert landscapes of re sandstone along with some unusual volcanics, while Jeddah and many small towns give insight to Saudi life.

Shifting pack ice is the barrier to both the North Pole and the North West Passage, requiring heroic explorations that were dominated by Nansen, Amundsen, Nobile, Andree, Peary and Herbert.

The challenges created by the ground conditions encountered during construction of the Panama Canal were a classic within the story of engineering geology in a complex world.

The scared mountain of Kailas rises like a beacon from the high plateau of Tibet, and a journey to it follows the pilgrim trail through the Himalayas and across some magnificent landscapes.

Clay causes ground subsidence when it is induced or accelerated by over-abstraction of groundwater, as is the case at Venice, where belated remedial action now protects the beautiful city.

The hundreds of artificial caves cut in the sandstone beneath Nottingham’s city centre offer a wealth of history and heritage and provide a few challenges for redeveloping the land above them.

The salt mountains within the Zagros Ranges of southern Iran are formed of diapirs of Precambrian salt, noted for active salt glaciers and with some amazing karst and beautiful caves within the salt.

The Afar Triangle at the mouth of the Red Sea is an incredibly hostile terrain of very hot desert where extension processes on a divergent plate boundary create new faults, grabens and active volcanoes.

Geology in action, Italian style, creates fun on the Lipari Islands, spectacle on Etna, drama on Stromboli, devastation at Vesuvius and potential excitement at Campi Flegrei.

Many cities, including Mexico City, Tokyo, Shanghai and Venice, lie on convenient flatlands that are underlain by clay, which shrinks when groundwater is abstraction, so causing regional subsidence.

Salt lakes, silver mines and volcanoes are among the geological wonders within beautiful deserts at high-altitude that form the altiplano between the ranges of the Andes in Bolivia, Peru and Chile.

In Russia’s Far East, the Kamchatka peninsula was inaccessible during the Cold War, but it houses a magnificent variety of volcanoes and associated features that make a geological visit so worthwhile.

The splendid landscapes carved in red sandstones in Utah and Arizona, dissected by the Grand Canyon, include the spectacular landscapes of Monument Valley, Bryce Canyon and many more.

A grand tour of the vast Arctic wildernesses of northwest America provides a host of geological treats among landscapes that range from beautiful to spectacular.

Thousands of stampeders headed for the Klondike in the winter of 1898 after George Carmack panned gold in a tributary of Canada’s Klondike River; and gold has been mined in the valley ever since.

Ground subsidence is a frequent challenge for construction engineers, and one of the greatest geohazards is created by collapse over cavernous ground, in limestone and other soluble rocks.

The landscapes of the high Arctic include some of the most beautiful in the world, not just with their glaciers and icebergs, but including the many unusual features of permafrost and ground ice.

Karst landscapes are created where drainage is underground, and this creates not only great cave systems, but also a suite of landscapes and landforms from simply dramatic to truly magnificent.

The remarkable Castleguard Cave that extends far beneath the Canada’s Columbia Icefield, and perhaps mimics conditions during the Ice Ages within may well-known caves.

A memorable journey by road from Shimla to Leh across the beautiful landscapes of the Himalaya and Zanskar Mountains, in a very small and totally unsuitable rented car.

The world’s most bizarre society is North Korea, where life has been so awful but is now showing signs of change and some modest improvements, though still under totalitarian control.

Sana’a is the capital city of Yemen, famed for its architecture and its great souks, set among sandstone mountains, and the island wilderness of Socotra has limestone landscapes noted for their flora.

A journey following the sacred river that is the Ganga starts in urban Calcutta, passes through the holy cities of Varanasi and Haridwar, glimpses the Taj Mahal and climbs to the foothills of the Himalaya.

Travels through the delightful land-locked nation of Laos, along the great Mekong River and off into the adjacent hill country, to call at remote villages and some beautiful Buddhist temples.

Travel the length of Baja California to see the splendid landscapes of this desert peninsula, then cross the Sea of Cortez to traverse the mainland mountains by way of the enormous Copper Canyon.

Travel around the margins of the Pacific Ocean to see the wealth of active geological processes where tectonic plates converge with great mountain chains, erupting volcanoes and major earthquakes.

Northwards from a snowbound St Petersburg, to Arkhangelsk and into the remote forests of Pinega where long gypsum caves are frozen wonderlands of icicles, ice sheets and giant ice crystals.

Vast expanses of bare rock, sparkling white ice and almost no greenery combine to create fabulous landscapes with a scatter of small towns and villages within a beautiful wilderness.

The entire island has been created by volcanoes, which still have periodic eruptions and have also create a fabulous landscape with geysers, glaciers and fjords across some beautiful wilderness.