Question: What geological event caused the foundations of the land beneath the city where most university graduates stay after acquiring a degree?

Knowledge 1: Houston
The University of Houston System's annual impact on the Houston area's economy equates to that of a major corporation: $1.1 billion in new funds attracted annually to the Houston area, $3.13 billion in total economic benefit and 24,000 local jobs generated. This is in addition to the 12,500 new graduates the U.H. System produces every year who enter the workforce in Houston and throughout the state of Texas. These degree-holders tend to stay in Houston. After five years, 80.5% of graduates are still living and working in the region. [SEP] Knowledge 2: Houston
Underpinning Houston's land surface are unconsolidated clays, clay shales, and poorly cemented sands up to several miles deep. The region's geology developed from river deposits formed from the erosion of the Rocky Mountains. These sediments consist of a series of sands and clays deposited on decaying organic marine matter, that over time, transformed into oil and natural gas. Beneath the layers of sediment is a water-deposited layer of halite, a rock salt. The porous layers were compressed over time and forced upward. As it pushed upward, the salt dragged surrounding sediments into salt dome formations, often trapping oil and gas that seeped from the surrounding porous sands. The thick, rich, sometimes black, surface soil is suitable for rice farming in suburban outskirts where the city continues to grow.
Knowledge 1: Houston
The University of Houston System's annual impact on the Houston area's economy equates to that of a major corporation: $1.1 billion in new funds attracted annually to the Houston area, $3.13 billion in total economic benefit and 24,000 local jobs generated. This is in addition to the 12,500 new graduates the U.H. System produces every year who enter the workforce in Houston and throughout the state of Texas. These degree-holders tend to stay in Houston. After five years, 80.5% of graduates are still living and working in the region. [SEP] Knowledge 2: Sharon Johnston
A native of Sault Ste. Marie, she completed her studies in physiotherapy and occupational therapy at the University of Toronto and received a BSc degree at the University of Western Ontario and an MSc degree at McGill University. She also graduated as a Doctor of Philosophy in rehabilitation science at McGill.
Knowledge 1: Houston
The University of Houston System's annual impact on the Houston area's economy equates to that of a major corporation: $1.1 billion in new funds attracted annually to the Houston area, $3.13 billion in total economic benefit and 24,000 local jobs generated. This is in addition to the 12,500 new graduates the U.H. System produces every year who enter the workforce in Houston and throughout the state of Texas. These degree-holders tend to stay in Houston. After five years, 80.5% of graduates are still living and working in the region. [SEP] Knowledge 2: Adly Mansour
Mansour was born in Cairo. He graduated from Cairo University Law School in 1967, earned a postgraduate degree in law in 1969, studied economics and earned a postgraduate degree in management science from Cairo University in 1970. He later attended France's École nationale d'administration (ENA) and graduated in 1977.

Answer: erosion of the Rocky Mountains