Who Is Daniel Robinson? Missing Geologist Disappeared in Arizona Desert

As investigators work towards identifying a cause of death for 22-year-old Gabby Petito, fresh appeals are being made to locate missing 24-year-old man Daniel Robinson.

Robinson, a geologist from Columbia, South Carolina, was last seen leaving a job site in the Arizona desert, 50 miles southwest of Phoenix, on June 23. He was reported missing later that day and has not been seen or heard from since.

The 24-year-old "had not told anyone where he was going or why he was leaving" and "was not like himself at times" in the days leading to his disappearance, the Buckeye Police Department said in a statement released in July, adding that there was no indication that he wished to harm himself or leave the area.

According to police, Robinson was last seen driving his 2017 Jeep Renegade, heading west, further into the desert area of Sun Valley Parkway just north of Cactus Road in Buckeye.

Investigators said a ping was established on his phone but no location data was available due to the phone being off or out of range. It did not appear that he had made any calls or texts after leaving the site.

On July 19, police were notified that Robinson's Jeep had been discovered by a rancher on his property approximately four miles southwest of the job site where he was last seen.

His jeep was found in a ravine with "significant damage" and "appear[ed] to have rolled and landed on its side," Buckeye Police said at the time, adding that Robinson's clothes, cell phone, wallet, and keys were all found at the scene.

Detectives searched the area on foot as well as conducting an aerial search via helicopter, and search and rescue dogs also canvassed the scene, however no sign of Robinson was found.

Police said that together with outside agencies using UTVs, cadaver dogs, a drone and a helicopter, they searched more than 70-square miles in an effort to locate the missing geologist to no avail.

"Based on the personal effects found in Daniel's vehicle, no foul play is suspected," Buckeye police added.

Later that month, on July 31, a human skull was found in an area south of where Robinson's Jeep had been recovered. It was later determined the remains did not belong to the missing man and no additional human remains have been found, authorities said.

Robinson had moved to Phoenix for his work and regularly worked on sites in remote desert locations, often in extreme conditions.

He is described as 5-foot-8 with black hair and brown eyes and does not have a right forearm or hand.

His father, David Robinson II, has traveled from his home in South Carolina to continue the search for answers and has set up a GoFundMe page to pay for a private investigator along with flyers, continued searches and other expenses.

"Daniel has an innate passion for adventure and is known to travel inopportune moments," a statement on the family's Please Help Find Daniel website reads. "However, he always communicates with friends and family about his travel plans."

More than $34,000 has been raised so far, with David pledging to stay on "indefinitely until we have answers and bring Daniel home safely."

The fundraiser has been set up because "the current investigation by law enforcement is not progressing," David Robinson wrote and pledged a $10,000 reward for anyone with information on his son's whereabouts.

According to WIS, the family hired private investigator Jeff McGrath to look into the disappearance.

Investigators hired by the family reportedly examined data from the Jeep's black box, showing the vehicle was driven 11 miles after the initial crash and that there were, in fact, multiple crashes and the vehicle damage didn't match the terrain where it was found.

The data also showed the car was "cranked" more than 40 times after the initial crash, indicating that someone may have been potentially trying repeatedly to start the engine again.

The private investigator said he also discovered one of Robinson's socks near the original worksite, which is located three miles from where the car was found.

"The problem is they think he wrecked his Jeep, undressed at the crash site, joined a monastery to become a monk, and it's the theory they stand on no matter what," David Robinson told WIS last week.

In addition to the website, David has also created an online petition calling for the police department to look more closely into his son's disappearance.

"From the first day that I arrived in Phoenix, Arizona, I have done more to find my son than the law enforcement agency, whose jurisdictional authority covers where he was last seen and where his vehicle was recovered," he wrote on a Change.org petition set up earlier this month. "The Buckeye PD investigation has not gathered any evidence of their own. They are unwilling to move beyond their theory which leads to non-action on their part," David Robinson continued to allege.

The family is asking for the status of the investigation to be changed from a missing person to a criminal investigation.

"The evidence is clear that this should be changed to a criminal investigation because my private investigator found that my son's vehicle was staged and that a possible crime had occurred," David Robinson said.

Searches initiated by the family and other members of the public have reportedly uncovered "close to five or six human remains" in the areas searched, the father said.

Newsweek has contacted the Buckeye Police Department for comment.