Complex sentence: They flowed across the Dogubeyazıt plain and along the southerly flowing Sarısu River and formed black ʻaʻā and pāhoehoe lava flows that contain well preserved lava tubes.
Split into simpler sentences: They flowed across the Dogubeyazıt plain and along the southerly flowing Sarısu River. These lava flows formed black ʻaʻā and pāhoehoe lava flows that contain well preserved lava tubes.