Hadde ikkje Hardangerfjordbreen mot slutten av istida rykt fram over fjordbotnen, ville Halsnøy ikkje eksistert som éi øy, men som mange småøyar. Breen skuva framfor seg så mykje leire frå havbotnen at Brattåsen, Toftåsen, Landåsen og Svartaberg vart samla i eitt landområde.
At nearly 1000 metres over sea level, on the north side of INGAHOGG mountain, the remains of a soapstone quarry have been discovered. It is said, according to the Sagas, that Inga collected the big soapstone that lies in front of the Åkra Church from here.
Skorpo - Polished by glaciers and meltwater
Ølve has a special soil type. Here one finds an extra hard clay soil. This is especially noticed by those who work with excavating for building foundations and the like. Often it is necessary to use especially big digging machines and sometimes even dynamite in order to break up the compact masses. The reason for this is the growth of the glaciers toward the end of the Ice Age: The clay, that was first deposited in front of the glacier, came under great pressure when the glacier later grew and slid out over the clay.
All in all there are ten known copper mines and two iron mines on the Ølve peninsula. Geologically, the nine mines on Varaldsøy Island also should be figured in. The industry began at Lilledal in 1642 wth the mining of iron ore. From Jernsmauget by Dyråsen, the iron ore was sent to the iron works in eastern Norway.
Fjøsanger is known among ice age researchers from around the world. Under an excavation in 1975-77, geologists from the University of Bergen found layers from the last interglacial, ca. 115 000 to 130 000 years old.