Based on the attached image;
The two processes that formed the unconformity at WZ are weathering and erosion.
Weathering involves the breaking down of rocks, soil, and minerals at the Earth's surface, by the action of rainwater, extremes of temperature and biological activity. It does not involve the removal of rock material. There are three types of weathering, physical, chemical and biological weathering. Erosion is the action of surface processes such as water flow or wind that remove soil, rock, or dissolved material from one location on the Earth's crust, and then transport it to another location.