Sentence examples for origin is not known from inspiring English sources

There are some plateaus whose origin is not known.

Their origin is not known; among many speculations are that they were brought to northern Europe by westward-migrating (possibly Celtic) tribes or that they developed indigenously.

The authorities interviewed him repeatedly on subsequent occasions, and had him listen to tape recordings -- their origin is not known -- to see if he could match them to the voice that he had heard in the call.

Their origin is not known; they are called Ghassulians because the pottery and flints characteristic of their settlements first attracted attention in the excavations of Tulaylāt al-Ghassūl in the Jordan Valley.

The date of its actual origin is not known, but legend associates Brahma with its creation concurrent with the lake; Brahma is said to have performed penance here for a darshan (sight) of god Vishnu.

The δ13C values of individual biomarkers were not determined in Atlantis Massif samples; therefore, their exact origin is not known but the results of our molecular analyses indicates that in situ microorganisms, and in particular methanotrophs, are the sources of biomarkers in 1309D.

Memorial Day dates back to the 19th century but its exact origin isn't known because at least 25 locations claim to be the holiday's birthplace.

The samples emanated from dairy farms in different parts of Sweden but the MRSA-screening was performed anonymously and epidemiological information of individual samples, such as geographical origin, was not known.

The mechanism by which telomere length feeds back to control nearby replication origins is not known at present, but seems unlikely to be fully explained by the effects of yeast Ku or SIR proteins on subtelomeric gene silencing and replication origin firing (Stevenson and Gottschling, 1999; Cosgrove et al, 2002).

Those source properties, together with information on the impedance (or admittance) of the system, allow predicting the coupled dynamic response of an assembly even though the detailed excitation origin in the source is not known.

Although Decius's origins are not known, it is certain that he was a senator and a consul before acceding to the throne.