Here's a brief overview of the top 10 countries in Oceania by GDP:

1. **Australia**: Leading the region, Australia's diverse economy is bolstered by mining, agriculture, and services. It is one of the wealthiest nations in the world, with strong trade links to Asia and the Pacific.

2. **New Zealand**: Known for its robust agricultural sector, New Zealand also has a growing technology industry and a significant tourism sector, contributing to its high GDP.

3. **Papua New Guinea**: Rich in natural resources, Papua New Guinea's economy is largely driven by mining, petroleum, and agriculture. Despite its wealth in resources, it faces challenges in infrastructure and development.

4. **Fiji**: Tourism is a major contributor to Fiji's economy, alongside sugar exports and a growing outsourcing sector.

5. **Solomon Islands**: This country's economy is primarily based on agriculture, fishing, and forestry, with logging being a significant export industry.

6. **New Caledonia (France)**: As a special collectivity of France, New Caledonia benefits from substantial French investment, with nickel mining playing a central role in its economy.

7. **French Polynesia (France)**: Another French overseas collectivity, French Polynesia's economy is driven by tourism, pearl farming, and agriculture.

8. **Vanuatu**: Tourism, agriculture, and offshore financial services are key sectors in Vanuatu's economy, contributing to its GDP growth.

9. **Samoa**: Samoa's economy is supported by agriculture, tourism, and remittances from Samoans living abroad.

10. **Micronesia (Federated States of)**: The economy of the Federated States of Micronesia relies heavily on aid from the United States, along with subsistence farming and fishing.

These countries showcase a variety of economic strengths, from resource extraction and agriculture to tourism and services. Despite the geographical isolation and varying levels of development, many of these nations have found unique ways to leverage their natural and cultural resources to boost their economies.