The phrase "remained preserved" is correct and can be used in written English.
Example: Despite the passage of time, the ancient artifacts remained preserved in the underground tomb.
Moreover, scientists still do not know when continents first formed, how they remained preserved for billions of years, or how they are likely to evolve in the future.
At one point, Łazanowski showed me a spot where the footprint of a German guard remained preserved in the concrete floor.
Related: From firewater to fine dining: exports triple for tequila's poor cousin, mezcal Fonseca predicted increasing demand could force a departure from the harvesting methods that have remained preserved for centuries.
In the Holocene, most of the previous grassland area changed into forest or forest-steppe and the Pleistocene biota retreated, with the exception of the Chuya Basin and the Ukok Plateau in the southeast, where the habitat change was very small and desert-steppe and associated vegetation types remained preserved.
Also, the immunoreactivity remained preserved under the conditions tested.
As seen in Figure 7, the quality of the natural resonance peaks remained preserved within the range of gain up to 5000 fold.
Of these, 113 titles and 3 play texts remain, preserved in an imperial collection of the 15th century.
In order to measure the attenuation of light by periphyton a method has been developed which assures that natural periphyton architecture and therefore its optical characteristics remain preserved.
And despite the crisis, the means allowing Europe to engage on vital global issues, such as development aid or climate change, remain preserved.
If it were not for the fact that many stories remain preserved on the Web, it would be like nothing had ever happened.
There, they fall into a jar filled with alcohol where they remain preserved until a researcher retrieves them.
