I have been reading Clive Cussler novels for many years and I can call myself a true fan of Cussler's pop fiction. Of course, Cussler does not aspire to the status of "belles lettres" (high-class literature worthy of study for its aesthetic value), but this author excels in his chosen genre of adventure ("action") novel and of books with plots that relate (at least in part) to sea-faring exploits or maritime curiosities. "Sahara" is among the best of Cussler's novels, among my very favourite of his exciting epics; only "The Mediterranean Caper", "Iceberg", and "Raise the Titantic" are as thrilling as "Sahara" is". There are few films based on Cussler novels, the only two of which I know being cinematic treatments of "Sahara", a great box-office success, and "Raise the Titanic" (a novel, hence the film too, whose plausibility suffers in retrospect only due to the discovery of the Titanic wreck well after Cussler had written his novel and after the film industry made a cinematic treatment of it). I read "Sahara" many years before the film came out. Both the novel and the film are "super"!
Cussler researches his subjects exceedingly well. The Tuaregs in "Sahara" are true to the life, religious beliefs and practices, and lore of this peculiar Muslim sect in Mali (e.g., whose men, rather than their women, wear an all-encompassing veil). Cussler's experience at sea, especially in exploring wrecks and naval mysteries, shows in all of his novels. Having been in the U.S. Navy myself (even having consorted for a few months with the "Navy Seals") during the Kennedy presidency in the early 1960s, I can appreciate the authenticity of Cussler's Naval and Maritime lore as he depicts it. In "Sahara" it takes the form of sub-plots that entail some expert manoeuvering under dangerous conditions of a small river craft vessel as well as the discovery of a marooned Confederacy warship.
The reader cannot go wrong with most of Cussler's novels especially those which were published before the present (21st) century began. "Sahara" makes a good point of departure in exploring the "Dirk Pitt" pop classics of Cussler's famously enjoyable 20th century output. If you liked the film treatment, you probably will enjoy the novel even more, if you are an avid reader of action fiction!